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TOMOYO Linux Cross Reference
Linux/kernel/seccomp.c

Version: ~ [ linux-6.12-rc7 ] ~ [ linux-6.11.7 ] ~ [ linux-6.10.14 ] ~ [ linux-6.9.12 ] ~ [ linux-6.8.12 ] ~ [ linux-6.7.12 ] ~ [ linux-6.6.60 ] ~ [ linux-6.5.13 ] ~ [ linux-6.4.16 ] ~ [ linux-6.3.13 ] ~ [ linux-6.2.16 ] ~ [ linux-6.1.116 ] ~ [ linux-6.0.19 ] ~ [ linux-5.19.17 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.171 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.229 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.285 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.323 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.336 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.337 ] ~ [ linux-4.4.302 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.12 ] ~ [ policy-sample ] ~
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Diff markup

Differences between /kernel/seccomp.c (Version linux-6.12-rc7) and /kernel/seccomp.c (Version linux-4.16.18)


  1 // SPDX-License-Identifier: GPL-2.0                 1 // SPDX-License-Identifier: GPL-2.0
  2 /*                                                  2 /*
  3  * linux/kernel/seccomp.c                           3  * linux/kernel/seccomp.c
  4  *                                                  4  *
  5  * Copyright 2004-2005  Andrea Arcangeli <andr      5  * Copyright 2004-2005  Andrea Arcangeli <andrea@cpushare.com>
  6  *                                                  6  *
  7  * Copyright (C) 2012 Google, Inc.                  7  * Copyright (C) 2012 Google, Inc.
  8  * Will Drewry <wad@chromium.org>                   8  * Will Drewry <wad@chromium.org>
  9  *                                                  9  *
 10  * This defines a simple but solid secure-comp     10  * This defines a simple but solid secure-computing facility.
 11  *                                                 11  *
 12  * Mode 1 uses a fixed list of allowed system      12  * Mode 1 uses a fixed list of allowed system calls.
 13  * Mode 2 allows user-defined system call filt     13  * Mode 2 allows user-defined system call filters in the form
 14  *        of Berkeley Packet Filters/Linux Soc     14  *        of Berkeley Packet Filters/Linux Socket Filters.
 15  */                                                15  */
 16 #define pr_fmt(fmt) "seccomp: " fmt            << 
 17                                                    16 
 18 #include <linux/refcount.h>                        17 #include <linux/refcount.h>
 19 #include <linux/audit.h>                           18 #include <linux/audit.h>
 20 #include <linux/compat.h>                          19 #include <linux/compat.h>
 21 #include <linux/coredump.h>                        20 #include <linux/coredump.h>
 22 #include <linux/kmemleak.h>                        21 #include <linux/kmemleak.h>
 23 #include <linux/nospec.h>                          22 #include <linux/nospec.h>
 24 #include <linux/prctl.h>                           23 #include <linux/prctl.h>
 25 #include <linux/sched.h>                           24 #include <linux/sched.h>
 26 #include <linux/sched/task_stack.h>                25 #include <linux/sched/task_stack.h>
 27 #include <linux/seccomp.h>                         26 #include <linux/seccomp.h>
 28 #include <linux/slab.h>                            27 #include <linux/slab.h>
 29 #include <linux/syscalls.h>                        28 #include <linux/syscalls.h>
 30 #include <linux/sysctl.h>                          29 #include <linux/sysctl.h>
 31                                                    30 
 32 /* Not exposed in headers: strictly internal u << 
 33 #define SECCOMP_MODE_DEAD       (SECCOMP_MODE_ << 
 34                                                << 
 35 #ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER             31 #ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
 36 #include <asm/syscall.h>                           32 #include <asm/syscall.h>
 37 #endif                                             33 #endif
 38                                                    34 
 39 #ifdef CONFIG_SECCOMP_FILTER                       35 #ifdef CONFIG_SECCOMP_FILTER
 40 #include <linux/file.h>                        << 
 41 #include <linux/filter.h>                          36 #include <linux/filter.h>
 42 #include <linux/pid.h>                             37 #include <linux/pid.h>
 43 #include <linux/ptrace.h>                          38 #include <linux/ptrace.h>
 44 #include <linux/capability.h>                  !!  39 #include <linux/security.h>
                                                   >>  40 #include <linux/tracehook.h>
 45 #include <linux/uaccess.h>                         41 #include <linux/uaccess.h>
 46 #include <linux/anon_inodes.h>                 << 
 47 #include <linux/lockdep.h>                     << 
 48                                                << 
 49 /*                                             << 
 50  * When SECCOMP_IOCTL_NOTIF_ID_VALID was first << 
 51  * wrong direction flag in the ioctl number. T << 
 52  * which the kernel needs to keep supporting u << 
 53  * using the wrong command number.             << 
 54  */                                            << 
 55 #define SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR << 
 56                                                << 
 57 enum notify_state {                            << 
 58         SECCOMP_NOTIFY_INIT,                   << 
 59         SECCOMP_NOTIFY_SENT,                   << 
 60         SECCOMP_NOTIFY_REPLIED,                << 
 61 };                                             << 
 62                                                << 
 63 struct seccomp_knotif {                        << 
 64         /* The struct pid of the task whose fi << 
 65         struct task_struct *task;              << 
 66                                                << 
 67         /* The "cookie" for this request; this << 
 68         u64 id;                                << 
 69                                                << 
 70         /*                                     << 
 71          * The seccomp data. This pointer is v << 
 72          * notification is active, since it co << 
 73          * eclipses the entire lifecycle here. << 
 74          */                                    << 
 75         const struct seccomp_data *data;       << 
 76                                                << 
 77         /*                                     << 
 78          * Notification states. When SECCOMP_R << 
 79          * struct seccomp_knotif is created an << 
 80          * handler reads the notification off  << 
 81          * If a signal is received the state t << 
 82          * another message is sent. When the u << 
 83          * transitions to REPLIED.             << 
 84          */                                    << 
 85         enum notify_state state;               << 
 86                                                << 
 87         /* The return values, only valid when  << 
 88         int error;                             << 
 89         long val;                              << 
 90         u32 flags;                             << 
 91                                                << 
 92         /*                                     << 
 93          * Signals when this has changed state << 
 94          * dying, a new seccomp addfd message, << 
 95          */                                    << 
 96         struct completion ready;               << 
 97                                                << 
 98         struct list_head list;                 << 
 99                                                << 
100         /* outstanding addfd requests */       << 
101         struct list_head addfd;                << 
102 };                                             << 
103                                                << 
104 /**                                            << 
105  * struct seccomp_kaddfd - container for secco << 
106  *                                             << 
107  * @file: A reference to the file to install i << 
108  * @fd: The fd number to install it at. If the << 
109  *      installing process should allocate the << 
110  * @flags: The flags for the new file descript << 
111  *         is allowed.                         << 
112  * @ioctl_flags: The flags used for the seccom << 
113  * @setfd: whether or not SECCOMP_ADDFD_FLAG_S << 
114  * @ret: The return value of the installing pr << 
115  *       upon success (>= 0).                  << 
116  * @completion: Indicates that the installing  << 
117  *              installation, or gone away (ei << 
118  *              reply, or signal)              << 
119  * @list: list_head for chaining seccomp_kaddf << 
120  *                                             << 
121  */                                            << 
122 struct seccomp_kaddfd {                        << 
123         struct file *file;                     << 
124         int fd;                                << 
125         unsigned int flags;                    << 
126         __u32 ioctl_flags;                     << 
127                                                << 
128         union {                                << 
129                 bool setfd;                    << 
130                 /* To only be set on reply */  << 
131                 int ret;                       << 
132         };                                     << 
133         struct completion completion;          << 
134         struct list_head list;                 << 
135 };                                             << 
136                                                << 
137 /**                                            << 
138  * struct notification - container for seccomp << 
139  * most seccomp filters will not have notifica << 
140  * structure is fairly large, we store the not << 
141  * separate structure.                         << 
142  *                                             << 
143  * @requests: A semaphore that users of this n << 
144  *            changes. Actual reads and writes << 
145  *            filter->notify_lock.             << 
146  * @flags: A set of SECCOMP_USER_NOTIF_FD_* fl << 
147  * @next_id: The id of the next request.       << 
148  * @notifications: A list of struct seccomp_kn << 
149  */                                            << 
150                                                << 
151 struct notification {                          << 
152         atomic_t requests;                     << 
153         u32 flags;                             << 
154         u64 next_id;                           << 
155         struct list_head notifications;        << 
156 };                                             << 
157                                                << 
158 #ifdef SECCOMP_ARCH_NATIVE                     << 
159 /**                                            << 
160  * struct action_cache - per-filter cache of s << 
161  * arch/syscall pair                           << 
162  *                                             << 
163  * @allow_native: A bitmap where each bit repr << 
164  *                filter will always allow the << 
165  *                native architecture.         << 
166  * @allow_compat: A bitmap where each bit repr << 
167  *                filter will always allow the << 
168  *                compat architecture.         << 
169  */                                            << 
170 struct action_cache {                          << 
171         DECLARE_BITMAP(allow_native, SECCOMP_A << 
172 #ifdef SECCOMP_ARCH_COMPAT                     << 
173         DECLARE_BITMAP(allow_compat, SECCOMP_A << 
174 #endif                                         << 
175 };                                             << 
176 #else                                          << 
177 struct action_cache { };                       << 
178                                                << 
179 static inline bool seccomp_cache_check_allow(c << 
180                                              c << 
181 {                                              << 
182         return false;                          << 
183 }                                              << 
184                                                << 
185 static inline void seccomp_cache_prepare(struc << 
186 {                                              << 
187 }                                              << 
188 #endif /* SECCOMP_ARCH_NATIVE */               << 
189                                                    42 
190 /**                                                43 /**
191  * struct seccomp_filter - container for secco     44  * struct seccomp_filter - container for seccomp BPF programs
192  *                                                 45  *
193  * @refs: Reference count to manage the object !!  46  * @usage: reference count to manage the object lifetime.
194  *        A filter's reference count is increm !!  47  *         get/put helpers should be used when accessing an instance
195  *        attached task, once for the dependen !!  48  *         outside of a lifetime-guarded section.  In general, this
196  *        requested for the user notifier. Whe !!  49  *         is only needed for handling filters shared across tasks.
197  *        the filter can be freed.             << 
198  * @users: A filter's @users count is incremen << 
199  *         attached task (filter installation, << 
200  *         and once for the dependent filter ( << 
201  *         When it reaches zero it indicates t << 
202  *         users of that filter exist. No new  << 
203  *         this filter after reaching 0. The @ << 
204  *         or equal to @refs. Hence, reaching  << 
205  *         the filter can be freed.            << 
206  * @cache: cache of arch/syscall mappings to a << 
207  * @log: true if all actions except for SECCOM     50  * @log: true if all actions except for SECCOMP_RET_ALLOW should be logged
208  * @wait_killable_recv: Put notifying process  << 
209  *                      notification is receiv << 
210  * @prev: points to a previously installed, or     51  * @prev: points to a previously installed, or inherited, filter
211  * @prog: the BPF program to evaluate              52  * @prog: the BPF program to evaluate
212  * @notif: the struct that holds all notificat << 
213  * @notify_lock: A lock for all notification-r << 
214  * @wqh: A wait queue for poll if a notifier i << 
215  *                                                 53  *
216  * seccomp_filter objects are organized in a t     54  * seccomp_filter objects are organized in a tree linked via the @prev
217  * pointer.  For any task, it appears to be a      55  * pointer.  For any task, it appears to be a singly-linked list starting
218  * with current->seccomp.filter, the most rece     56  * with current->seccomp.filter, the most recently attached or inherited filter.
219  * However, multiple filters may share a @prev     57  * However, multiple filters may share a @prev node, by way of fork(), which
220  * results in a unidirectional tree existing i     58  * results in a unidirectional tree existing in memory.  This is similar to
221  * how namespaces work.                            59  * how namespaces work.
222  *                                                 60  *
223  * seccomp_filter objects should never be modi     61  * seccomp_filter objects should never be modified after being attached
224  * to a task_struct (other than @refs).        !!  62  * to a task_struct (other than @usage).
225  */                                                63  */
226 struct seccomp_filter {                            64 struct seccomp_filter {
227         refcount_t refs;                       !!  65         refcount_t usage;
228         refcount_t users;                      << 
229         bool log;                                  66         bool log;
230         bool wait_killable_recv;               << 
231         struct action_cache cache;             << 
232         struct seccomp_filter *prev;               67         struct seccomp_filter *prev;
233         struct bpf_prog *prog;                     68         struct bpf_prog *prog;
234         struct notification *notif;            << 
235         struct mutex notify_lock;              << 
236         wait_queue_head_t wqh;                 << 
237 };                                                 69 };
238                                                    70 
239 /* Limit any path through the tree to 256KB wo     71 /* Limit any path through the tree to 256KB worth of instructions. */
240 #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof     72 #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter))
241                                                    73 
242 /*                                                 74 /*
243  * Endianness is explicitly ignored and left f     75  * Endianness is explicitly ignored and left for BPF program authors to manage
244  * as per the specific architecture.               76  * as per the specific architecture.
245  */                                                77  */
246 static void populate_seccomp_data(struct secco     78 static void populate_seccomp_data(struct seccomp_data *sd)
247 {                                                  79 {
248         /*                                     << 
249          * Instead of using current_pt_reg(),  << 
250          * to safely fetch "current", so just  << 
251          */                                    << 
252         struct task_struct *task = current;        80         struct task_struct *task = current;
253         struct pt_regs *regs = task_pt_regs(ta     81         struct pt_regs *regs = task_pt_regs(task);
254         unsigned long args[6];                     82         unsigned long args[6];
255                                                    83 
256         sd->nr = syscall_get_nr(task, regs);       84         sd->nr = syscall_get_nr(task, regs);
257         sd->arch = syscall_get_arch(task);     !!  85         sd->arch = syscall_get_arch();
258         syscall_get_arguments(task, regs, args !!  86         syscall_get_arguments(task, regs, 0, 6, args);
259         sd->args[0] = args[0];                     87         sd->args[0] = args[0];
260         sd->args[1] = args[1];                     88         sd->args[1] = args[1];
261         sd->args[2] = args[2];                     89         sd->args[2] = args[2];
262         sd->args[3] = args[3];                     90         sd->args[3] = args[3];
263         sd->args[4] = args[4];                     91         sd->args[4] = args[4];
264         sd->args[5] = args[5];                     92         sd->args[5] = args[5];
265         sd->instruction_pointer = KSTK_EIP(tas     93         sd->instruction_pointer = KSTK_EIP(task);
266 }                                                  94 }
267                                                    95 
268 /**                                                96 /**
269  *      seccomp_check_filter - verify seccomp      97  *      seccomp_check_filter - verify seccomp filter code
270  *      @filter: filter to verify                  98  *      @filter: filter to verify
271  *      @flen: length of filter                    99  *      @flen: length of filter
272  *                                                100  *
273  * Takes a previously checked filter (by bpf_c    101  * Takes a previously checked filter (by bpf_check_classic) and
274  * redirects all filter code that loads struct    102  * redirects all filter code that loads struct sk_buff data
275  * and related data through seccomp_bpf_load.     103  * and related data through seccomp_bpf_load.  It also
276  * enforces length and alignment checking of t    104  * enforces length and alignment checking of those loads.
277  *                                                105  *
278  * Returns 0 if the rule set is legal or -EINV    106  * Returns 0 if the rule set is legal or -EINVAL if not.
279  */                                               107  */
280 static int seccomp_check_filter(struct sock_fi    108 static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
281 {                                                 109 {
282         int pc;                                   110         int pc;
283         for (pc = 0; pc < flen; pc++) {           111         for (pc = 0; pc < flen; pc++) {
284                 struct sock_filter *ftest = &f    112                 struct sock_filter *ftest = &filter[pc];
285                 u16 code = ftest->code;           113                 u16 code = ftest->code;
286                 u32 k = ftest->k;                 114                 u32 k = ftest->k;
287                                                   115 
288                 switch (code) {                   116                 switch (code) {
289                 case BPF_LD | BPF_W | BPF_ABS:    117                 case BPF_LD | BPF_W | BPF_ABS:
290                         ftest->code = BPF_LDX     118                         ftest->code = BPF_LDX | BPF_W | BPF_ABS;
291                         /* 32-bit aligned and     119                         /* 32-bit aligned and not out of bounds. */
292                         if (k >= sizeof(struct    120                         if (k >= sizeof(struct seccomp_data) || k & 3)
293                                 return -EINVAL    121                                 return -EINVAL;
294                         continue;                 122                         continue;
295                 case BPF_LD | BPF_W | BPF_LEN:    123                 case BPF_LD | BPF_W | BPF_LEN:
296                         ftest->code = BPF_LD |    124                         ftest->code = BPF_LD | BPF_IMM;
297                         ftest->k = sizeof(stru    125                         ftest->k = sizeof(struct seccomp_data);
298                         continue;                 126                         continue;
299                 case BPF_LDX | BPF_W | BPF_LEN    127                 case BPF_LDX | BPF_W | BPF_LEN:
300                         ftest->code = BPF_LDX     128                         ftest->code = BPF_LDX | BPF_IMM;
301                         ftest->k = sizeof(stru    129                         ftest->k = sizeof(struct seccomp_data);
302                         continue;                 130                         continue;
303                 /* Explicitly include allowed     131                 /* Explicitly include allowed calls. */
304                 case BPF_RET | BPF_K:             132                 case BPF_RET | BPF_K:
305                 case BPF_RET | BPF_A:             133                 case BPF_RET | BPF_A:
306                 case BPF_ALU | BPF_ADD | BPF_K    134                 case BPF_ALU | BPF_ADD | BPF_K:
307                 case BPF_ALU | BPF_ADD | BPF_X    135                 case BPF_ALU | BPF_ADD | BPF_X:
308                 case BPF_ALU | BPF_SUB | BPF_K    136                 case BPF_ALU | BPF_SUB | BPF_K:
309                 case BPF_ALU | BPF_SUB | BPF_X    137                 case BPF_ALU | BPF_SUB | BPF_X:
310                 case BPF_ALU | BPF_MUL | BPF_K    138                 case BPF_ALU | BPF_MUL | BPF_K:
311                 case BPF_ALU | BPF_MUL | BPF_X    139                 case BPF_ALU | BPF_MUL | BPF_X:
312                 case BPF_ALU | BPF_DIV | BPF_K    140                 case BPF_ALU | BPF_DIV | BPF_K:
313                 case BPF_ALU | BPF_DIV | BPF_X    141                 case BPF_ALU | BPF_DIV | BPF_X:
314                 case BPF_ALU | BPF_AND | BPF_K    142                 case BPF_ALU | BPF_AND | BPF_K:
315                 case BPF_ALU | BPF_AND | BPF_X    143                 case BPF_ALU | BPF_AND | BPF_X:
316                 case BPF_ALU | BPF_OR | BPF_K:    144                 case BPF_ALU | BPF_OR | BPF_K:
317                 case BPF_ALU | BPF_OR | BPF_X:    145                 case BPF_ALU | BPF_OR | BPF_X:
318                 case BPF_ALU | BPF_XOR | BPF_K    146                 case BPF_ALU | BPF_XOR | BPF_K:
319                 case BPF_ALU | BPF_XOR | BPF_X    147                 case BPF_ALU | BPF_XOR | BPF_X:
320                 case BPF_ALU | BPF_LSH | BPF_K    148                 case BPF_ALU | BPF_LSH | BPF_K:
321                 case BPF_ALU | BPF_LSH | BPF_X    149                 case BPF_ALU | BPF_LSH | BPF_X:
322                 case BPF_ALU | BPF_RSH | BPF_K    150                 case BPF_ALU | BPF_RSH | BPF_K:
323                 case BPF_ALU | BPF_RSH | BPF_X    151                 case BPF_ALU | BPF_RSH | BPF_X:
324                 case BPF_ALU | BPF_NEG:           152                 case BPF_ALU | BPF_NEG:
325                 case BPF_LD | BPF_IMM:            153                 case BPF_LD | BPF_IMM:
326                 case BPF_LDX | BPF_IMM:           154                 case BPF_LDX | BPF_IMM:
327                 case BPF_MISC | BPF_TAX:          155                 case BPF_MISC | BPF_TAX:
328                 case BPF_MISC | BPF_TXA:          156                 case BPF_MISC | BPF_TXA:
329                 case BPF_LD | BPF_MEM:            157                 case BPF_LD | BPF_MEM:
330                 case BPF_LDX | BPF_MEM:           158                 case BPF_LDX | BPF_MEM:
331                 case BPF_ST:                      159                 case BPF_ST:
332                 case BPF_STX:                     160                 case BPF_STX:
333                 case BPF_JMP | BPF_JA:            161                 case BPF_JMP | BPF_JA:
334                 case BPF_JMP | BPF_JEQ | BPF_K    162                 case BPF_JMP | BPF_JEQ | BPF_K:
335                 case BPF_JMP | BPF_JEQ | BPF_X    163                 case BPF_JMP | BPF_JEQ | BPF_X:
336                 case BPF_JMP | BPF_JGE | BPF_K    164                 case BPF_JMP | BPF_JGE | BPF_K:
337                 case BPF_JMP | BPF_JGE | BPF_X    165                 case BPF_JMP | BPF_JGE | BPF_X:
338                 case BPF_JMP | BPF_JGT | BPF_K    166                 case BPF_JMP | BPF_JGT | BPF_K:
339                 case BPF_JMP | BPF_JGT | BPF_X    167                 case BPF_JMP | BPF_JGT | BPF_X:
340                 case BPF_JMP | BPF_JSET | BPF_    168                 case BPF_JMP | BPF_JSET | BPF_K:
341                 case BPF_JMP | BPF_JSET | BPF_    169                 case BPF_JMP | BPF_JSET | BPF_X:
342                         continue;                 170                         continue;
343                 default:                          171                 default:
344                         return -EINVAL;           172                         return -EINVAL;
345                 }                                 173                 }
346         }                                         174         }
347         return 0;                                 175         return 0;
348 }                                                 176 }
349                                                   177 
350 #ifdef SECCOMP_ARCH_NATIVE                     << 
351 static inline bool seccomp_cache_check_allow_b << 
352                                                << 
353                                                << 
354 {                                              << 
355         if (unlikely(syscall_nr < 0 || syscall << 
356                 return false;                  << 
357         syscall_nr = array_index_nospec(syscal << 
358                                                << 
359         return test_bit(syscall_nr, bitmap);   << 
360 }                                              << 
361                                                << 
362 /**                                            << 
363  * seccomp_cache_check_allow - lookup seccomp  << 
364  * @sfilter: The seccomp filter                << 
365  * @sd: The seccomp data to lookup the cache w << 
366  *                                             << 
367  * Returns true if the seccomp_data is cached  << 
368  */                                            << 
369 static inline bool seccomp_cache_check_allow(c << 
370                                              c << 
371 {                                              << 
372         int syscall_nr = sd->nr;               << 
373         const struct action_cache *cache = &sf << 
374                                                << 
375 #ifndef SECCOMP_ARCH_COMPAT                    << 
376         /* A native-only architecture doesn't  << 
377         return seccomp_cache_check_allow_bitma << 
378                                                << 
379                                                << 
380 #else                                          << 
381         if (likely(sd->arch == SECCOMP_ARCH_NA << 
382                 return seccomp_cache_check_all << 
383                                                << 
384                                                << 
385         if (likely(sd->arch == SECCOMP_ARCH_CO << 
386                 return seccomp_cache_check_all << 
387                                                << 
388                                                << 
389 #endif /* SECCOMP_ARCH_COMPAT */               << 
390                                                << 
391         WARN_ON_ONCE(true);                    << 
392         return false;                          << 
393 }                                              << 
394 #endif /* SECCOMP_ARCH_NATIVE */               << 
395                                                << 
396 #define ACTION_ONLY(ret) ((s32)((ret) & (SECCO << 
397 /**                                               178 /**
398  * seccomp_run_filters - evaluates all seccomp    179  * seccomp_run_filters - evaluates all seccomp filters against @sd
399  * @sd: optional seccomp data to be passed to     180  * @sd: optional seccomp data to be passed to filters
400  * @match: stores struct seccomp_filter that r    181  * @match: stores struct seccomp_filter that resulted in the return value,
401  *         unless filter returned SECCOMP_RET_    182  *         unless filter returned SECCOMP_RET_ALLOW, in which case it will
402  *         be unchanged.                          183  *         be unchanged.
403  *                                                184  *
404  * Returns valid seccomp BPF response codes.      185  * Returns valid seccomp BPF response codes.
405  */                                               186  */
                                                   >> 187 #define ACTION_ONLY(ret) ((s32)((ret) & (SECCOMP_RET_ACTION_FULL)))
406 static u32 seccomp_run_filters(const struct se    188 static u32 seccomp_run_filters(const struct seccomp_data *sd,
407                                struct seccomp_    189                                struct seccomp_filter **match)
408 {                                                 190 {
                                                   >> 191         struct seccomp_data sd_local;
409         u32 ret = SECCOMP_RET_ALLOW;              192         u32 ret = SECCOMP_RET_ALLOW;
410         /* Make sure cross-thread synced filte    193         /* Make sure cross-thread synced filter points somewhere sane. */
411         struct seccomp_filter *f =                194         struct seccomp_filter *f =
412                         READ_ONCE(current->sec    195                         READ_ONCE(current->seccomp.filter);
413                                                   196 
414         /* Ensure unexpected behavior doesn't     197         /* Ensure unexpected behavior doesn't result in failing open. */
415         if (WARN_ON(f == NULL))                !! 198         if (unlikely(WARN_ON(f == NULL)))
416                 return SECCOMP_RET_KILL_PROCES    199                 return SECCOMP_RET_KILL_PROCESS;
417                                                   200 
418         if (seccomp_cache_check_allow(f, sd))  !! 201         if (!sd) {
419                 return SECCOMP_RET_ALLOW;      !! 202                 populate_seccomp_data(&sd_local);
                                                   >> 203                 sd = &sd_local;
                                                   >> 204         }
420                                                   205 
421         /*                                        206         /*
422          * All filters in the list are evaluat    207          * All filters in the list are evaluated and the lowest BPF return
423          * value always takes priority (ignori    208          * value always takes priority (ignoring the DATA).
424          */                                       209          */
425         for (; f; f = f->prev) {                  210         for (; f; f = f->prev) {
426                 u32 cur_ret = bpf_prog_run_pin !! 211                 u32 cur_ret = BPF_PROG_RUN(f->prog, sd);
427                                                   212 
428                 if (ACTION_ONLY(cur_ret) < ACT    213                 if (ACTION_ONLY(cur_ret) < ACTION_ONLY(ret)) {
429                         ret = cur_ret;            214                         ret = cur_ret;
430                         *match = f;               215                         *match = f;
431                 }                                 216                 }
432         }                                         217         }
433         return ret;                               218         return ret;
434 }                                                 219 }
435 #endif /* CONFIG_SECCOMP_FILTER */                220 #endif /* CONFIG_SECCOMP_FILTER */
436                                                   221 
437 static inline bool seccomp_may_assign_mode(uns    222 static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode)
438 {                                                 223 {
439         assert_spin_locked(&current->sighand->    224         assert_spin_locked(&current->sighand->siglock);
440                                                   225 
441         if (current->seccomp.mode && current->    226         if (current->seccomp.mode && current->seccomp.mode != seccomp_mode)
442                 return false;                     227                 return false;
443                                                   228 
444         return true;                              229         return true;
445 }                                                 230 }
446                                                   231 
447 void __weak arch_seccomp_spec_mitigate(struct     232 void __weak arch_seccomp_spec_mitigate(struct task_struct *task) { }
448                                                   233 
449 static inline void seccomp_assign_mode(struct     234 static inline void seccomp_assign_mode(struct task_struct *task,
450                                        unsigne    235                                        unsigned long seccomp_mode,
451                                        unsigne    236                                        unsigned long flags)
452 {                                                 237 {
453         assert_spin_locked(&task->sighand->sig    238         assert_spin_locked(&task->sighand->siglock);
454                                                   239 
455         task->seccomp.mode = seccomp_mode;        240         task->seccomp.mode = seccomp_mode;
456         /*                                        241         /*
457          * Make sure SYSCALL_WORK_SECCOMP cann !! 242          * Make sure TIF_SECCOMP cannot be set before the mode (and
458          * filter) is set.                        243          * filter) is set.
459          */                                       244          */
460         smp_mb__before_atomic();                  245         smp_mb__before_atomic();
461         /* Assume default seccomp processes wa    246         /* Assume default seccomp processes want spec flaw mitigation. */
462         if ((flags & SECCOMP_FILTER_FLAG_SPEC_    247         if ((flags & SECCOMP_FILTER_FLAG_SPEC_ALLOW) == 0)
463                 arch_seccomp_spec_mitigate(tas    248                 arch_seccomp_spec_mitigate(task);
464         set_task_syscall_work(task, SECCOMP);  !! 249         set_tsk_thread_flag(task, TIF_SECCOMP);
465 }                                                 250 }
466                                                   251 
467 #ifdef CONFIG_SECCOMP_FILTER                      252 #ifdef CONFIG_SECCOMP_FILTER
468 /* Returns 1 if the parent is an ancestor of t    253 /* Returns 1 if the parent is an ancestor of the child. */
469 static int is_ancestor(struct seccomp_filter *    254 static int is_ancestor(struct seccomp_filter *parent,
470                        struct seccomp_filter *    255                        struct seccomp_filter *child)
471 {                                                 256 {
472         /* NULL is the root ancestor. */          257         /* NULL is the root ancestor. */
473         if (parent == NULL)                       258         if (parent == NULL)
474                 return 1;                         259                 return 1;
475         for (; child; child = child->prev)        260         for (; child; child = child->prev)
476                 if (child == parent)              261                 if (child == parent)
477                         return 1;                 262                         return 1;
478         return 0;                                 263         return 0;
479 }                                                 264 }
480                                                   265 
481 /**                                               266 /**
482  * seccomp_can_sync_threads: checks if all thr    267  * seccomp_can_sync_threads: checks if all threads can be synchronized
483  *                                                268  *
484  * Expects sighand and cred_guard_mutex locks     269  * Expects sighand and cred_guard_mutex locks to be held.
485  *                                                270  *
486  * Returns 0 on success, -ve on error, or the     271  * Returns 0 on success, -ve on error, or the pid of a thread which was
487  * either not in the correct seccomp mode or d !! 272  * either not in the correct seccomp mode or it did not have an ancestral
488  * seccomp filter.                                273  * seccomp filter.
489  */                                               274  */
490 static inline pid_t seccomp_can_sync_threads(v    275 static inline pid_t seccomp_can_sync_threads(void)
491 {                                                 276 {
492         struct task_struct *thread, *caller;      277         struct task_struct *thread, *caller;
493                                                   278 
494         BUG_ON(!mutex_is_locked(&current->sign    279         BUG_ON(!mutex_is_locked(&current->signal->cred_guard_mutex));
495         assert_spin_locked(&current->sighand->    280         assert_spin_locked(&current->sighand->siglock);
496                                                   281 
497         /* Validate all threads being eligible    282         /* Validate all threads being eligible for synchronization. */
498         caller = current;                         283         caller = current;
499         for_each_thread(caller, thread) {         284         for_each_thread(caller, thread) {
500                 pid_t failed;                     285                 pid_t failed;
501                                                   286 
502                 /* Skip current, since it is i    287                 /* Skip current, since it is initiating the sync. */
503                 if (thread == caller)             288                 if (thread == caller)
504                         continue;                 289                         continue;
505                 /* Skip exited threads. */     << 
506                 if (thread->flags & PF_EXITING << 
507                         continue;              << 
508                                                   290 
509                 if (thread->seccomp.mode == SE    291                 if (thread->seccomp.mode == SECCOMP_MODE_DISABLED ||
510                     (thread->seccomp.mode == S    292                     (thread->seccomp.mode == SECCOMP_MODE_FILTER &&
511                      is_ancestor(thread->secco    293                      is_ancestor(thread->seccomp.filter,
512                                  caller->secco    294                                  caller->seccomp.filter)))
513                         continue;                 295                         continue;
514                                                   296 
515                 /* Return the first thread tha    297                 /* Return the first thread that cannot be synchronized. */
516                 failed = task_pid_vnr(thread);    298                 failed = task_pid_vnr(thread);
517                 /* If the pid cannot be resolv    299                 /* If the pid cannot be resolved, then return -ESRCH */
518                 if (WARN_ON(failed == 0))      !! 300                 if (unlikely(WARN_ON(failed == 0)))
519                         failed = -ESRCH;          301                         failed = -ESRCH;
520                 return failed;                    302                 return failed;
521         }                                         303         }
522                                                   304 
523         return 0;                                 305         return 0;
524 }                                                 306 }
525                                                   307 
526 static inline void seccomp_filter_free(struct  << 
527 {                                              << 
528         if (filter) {                          << 
529                 bpf_prog_destroy(filter->prog) << 
530                 kfree(filter);                 << 
531         }                                      << 
532 }                                              << 
533                                                << 
534 static void __seccomp_filter_orphan(struct sec << 
535 {                                              << 
536         while (orig && refcount_dec_and_test(& << 
537                 if (waitqueue_active(&orig->wq << 
538                         wake_up_poll(&orig->wq << 
539                 orig = orig->prev;             << 
540         }                                      << 
541 }                                              << 
542                                                << 
543 static void __put_seccomp_filter(struct seccom << 
544 {                                              << 
545         /* Clean up single-reference branches  << 
546         while (orig && refcount_dec_and_test(& << 
547                 struct seccomp_filter *freeme  << 
548                 orig = orig->prev;             << 
549                 seccomp_filter_free(freeme);   << 
550         }                                      << 
551 }                                              << 
552                                                << 
553 static void __seccomp_filter_release(struct se << 
554 {                                              << 
555         /* Notify about any unused filters in  << 
556         __seccomp_filter_orphan(orig);         << 
557         /* Finally drop all references to the  << 
558         __put_seccomp_filter(orig);            << 
559 }                                              << 
560                                                << 
561 /**                                            << 
562  * seccomp_filter_release - Detach the task fr << 
563  *                          drop its reference << 
564  *                          about unused filte << 
565  *                                             << 
566  * @tsk: task the filter should be released fr << 
567  *                                             << 
568  * This function should only be called when th << 
569  * it detaches it from its filter tree. PF_EXI << 
570  * for the task.                               << 
571  */                                            << 
572 void seccomp_filter_release(struct task_struct << 
573 {                                              << 
574         struct seccomp_filter *orig;           << 
575                                                << 
576         if (WARN_ON((tsk->flags & PF_EXITING)  << 
577                 return;                        << 
578                                                << 
579         spin_lock_irq(&tsk->sighand->siglock); << 
580         orig = tsk->seccomp.filter;            << 
581         /* Detach task from its filter tree. * << 
582         tsk->seccomp.filter = NULL;            << 
583         spin_unlock_irq(&tsk->sighand->siglock << 
584         __seccomp_filter_release(orig);        << 
585 }                                              << 
586                                                << 
587 /**                                               308 /**
588  * seccomp_sync_threads: sets all threads to u    309  * seccomp_sync_threads: sets all threads to use current's filter
589  *                                                310  *
590  * @flags: SECCOMP_FILTER_FLAG_* flags to set  << 
591  *                                             << 
592  * Expects sighand and cred_guard_mutex locks     311  * Expects sighand and cred_guard_mutex locks to be held, and for
593  * seccomp_can_sync_threads() to have returned    312  * seccomp_can_sync_threads() to have returned success already
594  * without dropping the locks.                    313  * without dropping the locks.
595  *                                                314  *
596  */                                               315  */
597 static inline void seccomp_sync_threads(unsign    316 static inline void seccomp_sync_threads(unsigned long flags)
598 {                                                 317 {
599         struct task_struct *thread, *caller;      318         struct task_struct *thread, *caller;
600                                                   319 
601         BUG_ON(!mutex_is_locked(&current->sign    320         BUG_ON(!mutex_is_locked(&current->signal->cred_guard_mutex));
602         assert_spin_locked(&current->sighand->    321         assert_spin_locked(&current->sighand->siglock);
603                                                   322 
604         /* Synchronize all threads. */            323         /* Synchronize all threads. */
605         caller = current;                         324         caller = current;
606         for_each_thread(caller, thread) {         325         for_each_thread(caller, thread) {
607                 /* Skip current, since it need    326                 /* Skip current, since it needs no changes. */
608                 if (thread == caller)             327                 if (thread == caller)
609                         continue;                 328                         continue;
610                                                   329 
611                 /*                             << 
612                  * Skip exited threads. seccom << 
613                  * been already called for thi << 
614                  */                            << 
615                 if (thread->flags & PF_EXITING << 
616                         continue;              << 
617                                                << 
618                 /* Get a task reference for th    330                 /* Get a task reference for the new leaf node. */
619                 get_seccomp_filter(caller);       331                 get_seccomp_filter(caller);
620                                                << 
621                 /*                                332                 /*
622                  * Drop the task reference to     333                  * Drop the task reference to the shared ancestor since
623                  * current's path will hold a     334                  * current's path will hold a reference.  (This also
624                  * allows a put before the ass    335                  * allows a put before the assignment.)
625                  */                               336                  */
626                 __seccomp_filter_release(threa !! 337                 put_seccomp_filter(thread);
627                                                << 
628                 /* Make our new filter tree vi << 
629                 smp_store_release(&thread->sec    338                 smp_store_release(&thread->seccomp.filter,
630                                   caller->secc    339                                   caller->seccomp.filter);
631                 atomic_set(&thread->seccomp.fi << 
632                            atomic_read(&caller << 
633                                                   340 
634                 /*                                341                 /*
635                  * Don't let an unprivileged t    342                  * Don't let an unprivileged task work around
636                  * the no_new_privs restrictio    343                  * the no_new_privs restriction by creating
637                  * a thread that sets it up, e    344                  * a thread that sets it up, enters seccomp,
638                  * then dies.                     345                  * then dies.
639                  */                               346                  */
640                 if (task_no_new_privs(caller))    347                 if (task_no_new_privs(caller))
641                         task_set_no_new_privs(    348                         task_set_no_new_privs(thread);
642                                                   349 
643                 /*                                350                 /*
644                  * Opt the other thread into s    351                  * Opt the other thread into seccomp if needed.
645                  * As threads are considered t    352                  * As threads are considered to be trust-realm
646                  * equivalent (see ptrace_may_    353                  * equivalent (see ptrace_may_access), it is safe to
647                  * allow one thread to transit    354                  * allow one thread to transition the other.
648                  */                               355                  */
649                 if (thread->seccomp.mode == SE    356                 if (thread->seccomp.mode == SECCOMP_MODE_DISABLED)
650                         seccomp_assign_mode(th    357                         seccomp_assign_mode(thread, SECCOMP_MODE_FILTER,
651                                             fl    358                                             flags);
652         }                                         359         }
653 }                                                 360 }
654                                                   361 
655 /**                                               362 /**
656  * seccomp_prepare_filter: Prepares a seccomp     363  * seccomp_prepare_filter: Prepares a seccomp filter for use.
657  * @fprog: BPF program to install                 364  * @fprog: BPF program to install
658  *                                                365  *
659  * Returns filter on success or an ERR_PTR on     366  * Returns filter on success or an ERR_PTR on failure.
660  */                                               367  */
661 static struct seccomp_filter *seccomp_prepare_    368 static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
662 {                                                 369 {
663         struct seccomp_filter *sfilter;           370         struct seccomp_filter *sfilter;
664         int ret;                                  371         int ret;
665         const bool save_orig =                 !! 372         const bool save_orig = IS_ENABLED(CONFIG_CHECKPOINT_RESTORE);
666 #if defined(CONFIG_CHECKPOINT_RESTORE) || defi << 
667                 true;                          << 
668 #else                                          << 
669                 false;                         << 
670 #endif                                         << 
671                                                   373 
672         if (fprog->len == 0 || fprog->len > BP    374         if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
673                 return ERR_PTR(-EINVAL);          375                 return ERR_PTR(-EINVAL);
674                                                   376 
675         BUG_ON(INT_MAX / fprog->len < sizeof(s    377         BUG_ON(INT_MAX / fprog->len < sizeof(struct sock_filter));
676                                                   378 
677         /*                                        379         /*
678          * Installing a seccomp filter require    380          * Installing a seccomp filter requires that the task has
679          * CAP_SYS_ADMIN in its namespace or b    381          * CAP_SYS_ADMIN in its namespace or be running with no_new_privs.
680          * This avoids scenarios where unprivi    382          * This avoids scenarios where unprivileged tasks can affect the
681          * behavior of privileged children.       383          * behavior of privileged children.
682          */                                       384          */
683         if (!task_no_new_privs(current) &&        385         if (!task_no_new_privs(current) &&
684                         !ns_capable_noaudit(cu !! 386             security_capable_noaudit(current_cred(), current_user_ns(),
                                                   >> 387                                      CAP_SYS_ADMIN) != 0)
685                 return ERR_PTR(-EACCES);          388                 return ERR_PTR(-EACCES);
686                                                   389 
687         /* Allocate a new seccomp_filter */       390         /* Allocate a new seccomp_filter */
688         sfilter = kzalloc(sizeof(*sfilter), GF    391         sfilter = kzalloc(sizeof(*sfilter), GFP_KERNEL | __GFP_NOWARN);
689         if (!sfilter)                             392         if (!sfilter)
690                 return ERR_PTR(-ENOMEM);          393                 return ERR_PTR(-ENOMEM);
691                                                   394 
692         mutex_init(&sfilter->notify_lock);     << 
693         ret = bpf_prog_create_from_user(&sfilt    395         ret = bpf_prog_create_from_user(&sfilter->prog, fprog,
694                                         seccom    396                                         seccomp_check_filter, save_orig);
695         if (ret < 0) {                            397         if (ret < 0) {
696                 kfree(sfilter);                   398                 kfree(sfilter);
697                 return ERR_PTR(ret);              399                 return ERR_PTR(ret);
698         }                                         400         }
699                                                   401 
700         refcount_set(&sfilter->refs, 1);       !! 402         refcount_set(&sfilter->usage, 1);
701         refcount_set(&sfilter->users, 1);      << 
702         init_waitqueue_head(&sfilter->wqh);    << 
703                                                   403 
704         return sfilter;                           404         return sfilter;
705 }                                                 405 }
706                                                   406 
707 /**                                               407 /**
708  * seccomp_prepare_user_filter - prepares a us    408  * seccomp_prepare_user_filter - prepares a user-supplied sock_fprog
709  * @user_filter: pointer to the user data cont    409  * @user_filter: pointer to the user data containing a sock_fprog.
710  *                                                410  *
711  * Returns 0 on success and non-zero otherwise    411  * Returns 0 on success and non-zero otherwise.
712  */                                               412  */
713 static struct seccomp_filter *                    413 static struct seccomp_filter *
714 seccomp_prepare_user_filter(const char __user     414 seccomp_prepare_user_filter(const char __user *user_filter)
715 {                                                 415 {
716         struct sock_fprog fprog;                  416         struct sock_fprog fprog;
717         struct seccomp_filter *filter = ERR_PT    417         struct seccomp_filter *filter = ERR_PTR(-EFAULT);
718                                                   418 
719 #ifdef CONFIG_COMPAT                              419 #ifdef CONFIG_COMPAT
720         if (in_compat_syscall()) {                420         if (in_compat_syscall()) {
721                 struct compat_sock_fprog fprog    421                 struct compat_sock_fprog fprog32;
722                 if (copy_from_user(&fprog32, u    422                 if (copy_from_user(&fprog32, user_filter, sizeof(fprog32)))
723                         goto out;                 423                         goto out;
724                 fprog.len = fprog32.len;          424                 fprog.len = fprog32.len;
725                 fprog.filter = compat_ptr(fpro    425                 fprog.filter = compat_ptr(fprog32.filter);
726         } else /* falls through to the if belo    426         } else /* falls through to the if below. */
727 #endif                                            427 #endif
728         if (copy_from_user(&fprog, user_filter    428         if (copy_from_user(&fprog, user_filter, sizeof(fprog)))
729                 goto out;                         429                 goto out;
730         filter = seccomp_prepare_filter(&fprog    430         filter = seccomp_prepare_filter(&fprog);
731 out:                                              431 out:
732         return filter;                            432         return filter;
733 }                                                 433 }
734                                                   434 
735 #ifdef SECCOMP_ARCH_NATIVE                     << 
736 /**                                            << 
737  * seccomp_is_const_allow - check if filter is << 
738  * @fprog: The BPF programs                    << 
739  * @sd: The seccomp data to check against, onl << 
740  *      number are considered constant.        << 
741  */                                            << 
742 static bool seccomp_is_const_allow(struct sock << 
743                                    struct secc << 
744 {                                              << 
745         unsigned int reg_value = 0;            << 
746         unsigned int pc;                       << 
747         bool op_res;                           << 
748                                                << 
749         if (WARN_ON_ONCE(!fprog))              << 
750                 return false;                  << 
751                                                << 
752         for (pc = 0; pc < fprog->len; pc++) {  << 
753                 struct sock_filter *insn = &fp << 
754                 u16 code = insn->code;         << 
755                 u32 k = insn->k;               << 
756                                                << 
757                 switch (code) {                << 
758                 case BPF_LD | BPF_W | BPF_ABS: << 
759                         switch (k) {           << 
760                         case offsetof(struct s << 
761                                 reg_value = sd << 
762                                 break;         << 
763                         case offsetof(struct s << 
764                                 reg_value = sd << 
765                                 break;         << 
766                         default:               << 
767                                 /* can't optim << 
768                                 return false;  << 
769                         }                      << 
770                         break;                 << 
771                 case BPF_RET | BPF_K:          << 
772                         /* reached return with << 
773                         return k == SECCOMP_RE << 
774                 case BPF_JMP | BPF_JA:         << 
775                         pc += insn->k;         << 
776                         break;                 << 
777                 case BPF_JMP | BPF_JEQ | BPF_K << 
778                 case BPF_JMP | BPF_JGE | BPF_K << 
779                 case BPF_JMP | BPF_JGT | BPF_K << 
780                 case BPF_JMP | BPF_JSET | BPF_ << 
781                         switch (BPF_OP(code))  << 
782                         case BPF_JEQ:          << 
783                                 op_res = reg_v << 
784                                 break;         << 
785                         case BPF_JGE:          << 
786                                 op_res = reg_v << 
787                                 break;         << 
788                         case BPF_JGT:          << 
789                                 op_res = reg_v << 
790                                 break;         << 
791                         case BPF_JSET:         << 
792                                 op_res = !!(re << 
793                                 break;         << 
794                         default:               << 
795                                 /* can't optim << 
796                                 return false;  << 
797                         }                      << 
798                                                << 
799                         pc += op_res ? insn->j << 
800                         break;                 << 
801                 case BPF_ALU | BPF_AND | BPF_K << 
802                         reg_value &= k;        << 
803                         break;                 << 
804                 default:                       << 
805                         /* can't optimize (unk << 
806                         return false;          << 
807                 }                              << 
808         }                                      << 
809                                                << 
810         /* ran off the end of the filter?! */  << 
811         WARN_ON(1);                            << 
812         return false;                          << 
813 }                                              << 
814                                                << 
815 static void seccomp_cache_prepare_bitmap(struc << 
816                                          void  << 
817                                          size_ << 
818 {                                              << 
819         struct sock_fprog_kern *fprog = sfilte << 
820         struct seccomp_data sd;                << 
821         int nr;                                << 
822                                                << 
823         if (bitmap_prev) {                     << 
824                 /* The new filter must be as r << 
825                 bitmap_copy(bitmap, bitmap_pre << 
826         } else {                               << 
827                 /* Before any filters, all sys << 
828                 bitmap_fill(bitmap, bitmap_siz << 
829         }                                      << 
830                                                << 
831         for (nr = 0; nr < bitmap_size; nr++) { << 
832                 /* No bitmap change: not a cac << 
833                 if (!test_bit(nr, bitmap))     << 
834                         continue;              << 
835                                                << 
836                 sd.nr = nr;                    << 
837                 sd.arch = arch;                << 
838                                                << 
839                 /* No bitmap change: continue  << 
840                 if (seccomp_is_const_allow(fpr << 
841                         continue;              << 
842                                                << 
843                 /*                             << 
844                  * Not a cacheable action: alw << 
845                  * atomic clear_bit() not need << 
846                  */                            << 
847                 __clear_bit(nr, bitmap);       << 
848         }                                      << 
849 }                                              << 
850                                                << 
851 /**                                            << 
852  * seccomp_cache_prepare - emulate the filter  << 
853  * @sfilter: The seccomp filter                << 
854  *                                             << 
855  * Returns 0 if successful or -errno if error  << 
856  */                                            << 
857 static void seccomp_cache_prepare(struct secco << 
858 {                                              << 
859         struct action_cache *cache = &sfilter- << 
860         const struct action_cache *cache_prev  << 
861                 sfilter->prev ? &sfilter->prev << 
862                                                << 
863         seccomp_cache_prepare_bitmap(sfilter,  << 
864                                      cache_pre << 
865                                      SECCOMP_A << 
866                                      SECCOMP_A << 
867                                                << 
868 #ifdef SECCOMP_ARCH_COMPAT                     << 
869         seccomp_cache_prepare_bitmap(sfilter,  << 
870                                      cache_pre << 
871                                      SECCOMP_A << 
872                                      SECCOMP_A << 
873 #endif /* SECCOMP_ARCH_COMPAT */               << 
874 }                                              << 
875 #endif /* SECCOMP_ARCH_NATIVE */               << 
876                                                << 
877 /**                                               435 /**
878  * seccomp_attach_filter: validate and attach     436  * seccomp_attach_filter: validate and attach filter
879  * @flags:  flags to change filter behavior       437  * @flags:  flags to change filter behavior
880  * @filter: seccomp filter to add to the curre    438  * @filter: seccomp filter to add to the current process
881  *                                                439  *
882  * Caller must be holding current->sighand->si    440  * Caller must be holding current->sighand->siglock lock.
883  *                                                441  *
884  * Returns 0 on success, -ve on error, or      !! 442  * Returns 0 on success, -ve on error.
885  *   - in TSYNC mode: the pid of a thread whic << 
886  *     seccomp mode or did not have an ancestr << 
887  *   - in NEW_LISTENER mode: the fd of the new << 
888  */                                               443  */
889 static long seccomp_attach_filter(unsigned int    444 static long seccomp_attach_filter(unsigned int flags,
890                                   struct secco    445                                   struct seccomp_filter *filter)
891 {                                                 446 {
892         unsigned long total_insns;                447         unsigned long total_insns;
893         struct seccomp_filter *walker;            448         struct seccomp_filter *walker;
894                                                   449 
895         assert_spin_locked(&current->sighand->    450         assert_spin_locked(&current->sighand->siglock);
896                                                   451 
897         /* Validate resulting filter length. *    452         /* Validate resulting filter length. */
898         total_insns = filter->prog->len;          453         total_insns = filter->prog->len;
899         for (walker = current->seccomp.filter;    454         for (walker = current->seccomp.filter; walker; walker = walker->prev)
900                 total_insns += walker->prog->l    455                 total_insns += walker->prog->len + 4;  /* 4 instr penalty */
901         if (total_insns > MAX_INSNS_PER_PATH)     456         if (total_insns > MAX_INSNS_PER_PATH)
902                 return -ENOMEM;                   457                 return -ENOMEM;
903                                                   458 
904         /* If thread sync has been requested,     459         /* If thread sync has been requested, check that it is possible. */
905         if (flags & SECCOMP_FILTER_FLAG_TSYNC)    460         if (flags & SECCOMP_FILTER_FLAG_TSYNC) {
906                 int ret;                          461                 int ret;
907                                                   462 
908                 ret = seccomp_can_sync_threads    463                 ret = seccomp_can_sync_threads();
909                 if (ret) {                     !! 464                 if (ret)
910                         if (flags & SECCOMP_FI !! 465                         return ret;
911                                 return -ESRCH; << 
912                         else                   << 
913                                 return ret;    << 
914                 }                              << 
915         }                                         466         }
916                                                   467 
917         /* Set log flag, if present. */           468         /* Set log flag, if present. */
918         if (flags & SECCOMP_FILTER_FLAG_LOG)      469         if (flags & SECCOMP_FILTER_FLAG_LOG)
919                 filter->log = true;               470                 filter->log = true;
920                                                   471 
921         /* Set wait killable flag, if present. << 
922         if (flags & SECCOMP_FILTER_FLAG_WAIT_K << 
923                 filter->wait_killable_recv = t << 
924                                                << 
925         /*                                        472         /*
926          * If there is an existing filter, mak    473          * If there is an existing filter, make it the prev and don't drop its
927          * task reference.                        474          * task reference.
928          */                                       475          */
929         filter->prev = current->seccomp.filter    476         filter->prev = current->seccomp.filter;
930         seccomp_cache_prepare(filter);         << 
931         current->seccomp.filter = filter;         477         current->seccomp.filter = filter;
932         atomic_inc(&current->seccomp.filter_co << 
933                                                   478 
934         /* Now that the new filter is in place    479         /* Now that the new filter is in place, synchronize to all threads. */
935         if (flags & SECCOMP_FILTER_FLAG_TSYNC)    480         if (flags & SECCOMP_FILTER_FLAG_TSYNC)
936                 seccomp_sync_threads(flags);      481                 seccomp_sync_threads(flags);
937                                                   482 
938         return 0;                                 483         return 0;
939 }                                                 484 }
940                                                   485 
941 static void __get_seccomp_filter(struct seccom    486 static void __get_seccomp_filter(struct seccomp_filter *filter)
942 {                                                 487 {
943         refcount_inc(&filter->refs);           !! 488         /* Reference count is bounded by the number of total processes. */
                                                   >> 489         refcount_inc(&filter->usage);
944 }                                                 490 }
945                                                   491 
946 /* get_seccomp_filter - increments the referen    492 /* get_seccomp_filter - increments the reference count of the filter on @tsk */
947 void get_seccomp_filter(struct task_struct *ts    493 void get_seccomp_filter(struct task_struct *tsk)
948 {                                                 494 {
949         struct seccomp_filter *orig = tsk->sec    495         struct seccomp_filter *orig = tsk->seccomp.filter;
950         if (!orig)                                496         if (!orig)
951                 return;                           497                 return;
952         __get_seccomp_filter(orig);               498         __get_seccomp_filter(orig);
953         refcount_inc(&orig->users);            << 
954 }                                                 499 }
955                                                   500 
                                                   >> 501 static inline void seccomp_filter_free(struct seccomp_filter *filter)
                                                   >> 502 {
                                                   >> 503         if (filter) {
                                                   >> 504                 bpf_prog_destroy(filter->prog);
                                                   >> 505                 kfree(filter);
                                                   >> 506         }
                                                   >> 507 }
                                                   >> 508 
                                                   >> 509 static void __put_seccomp_filter(struct seccomp_filter *orig)
                                                   >> 510 {
                                                   >> 511         /* Clean up single-reference branches iteratively. */
                                                   >> 512         while (orig && refcount_dec_and_test(&orig->usage)) {
                                                   >> 513                 struct seccomp_filter *freeme = orig;
                                                   >> 514                 orig = orig->prev;
                                                   >> 515                 seccomp_filter_free(freeme);
                                                   >> 516         }
                                                   >> 517 }
                                                   >> 518 
                                                   >> 519 /* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */
                                                   >> 520 void put_seccomp_filter(struct task_struct *tsk)
                                                   >> 521 {
                                                   >> 522         __put_seccomp_filter(tsk->seccomp.filter);
                                                   >> 523 }
                                                   >> 524 
                                                   >> 525 static void seccomp_init_siginfo(siginfo_t *info, int syscall, int reason)
                                                   >> 526 {
                                                   >> 527         clear_siginfo(info);
                                                   >> 528         info->si_signo = SIGSYS;
                                                   >> 529         info->si_code = SYS_SECCOMP;
                                                   >> 530         info->si_call_addr = (void __user *)KSTK_EIP(current);
                                                   >> 531         info->si_errno = reason;
                                                   >> 532         info->si_arch = syscall_get_arch();
                                                   >> 533         info->si_syscall = syscall;
                                                   >> 534 }
                                                   >> 535 
                                                   >> 536 /**
                                                   >> 537  * seccomp_send_sigsys - signals the task to allow in-process syscall emulation
                                                   >> 538  * @syscall: syscall number to send to userland
                                                   >> 539  * @reason: filter-supplied reason code to send to userland (via si_errno)
                                                   >> 540  *
                                                   >> 541  * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info.
                                                   >> 542  */
                                                   >> 543 static void seccomp_send_sigsys(int syscall, int reason)
                                                   >> 544 {
                                                   >> 545         struct siginfo info;
                                                   >> 546         seccomp_init_siginfo(&info, syscall, reason);
                                                   >> 547         force_sig_info(SIGSYS, &info, current);
                                                   >> 548 }
956 #endif  /* CONFIG_SECCOMP_FILTER */               549 #endif  /* CONFIG_SECCOMP_FILTER */
957                                                   550 
958 /* For use with seccomp_actions_logged */         551 /* For use with seccomp_actions_logged */
959 #define SECCOMP_LOG_KILL_PROCESS        (1 <<     552 #define SECCOMP_LOG_KILL_PROCESS        (1 << 0)
960 #define SECCOMP_LOG_KILL_THREAD         (1 <<     553 #define SECCOMP_LOG_KILL_THREAD         (1 << 1)
961 #define SECCOMP_LOG_TRAP                (1 <<     554 #define SECCOMP_LOG_TRAP                (1 << 2)
962 #define SECCOMP_LOG_ERRNO               (1 <<     555 #define SECCOMP_LOG_ERRNO               (1 << 3)
963 #define SECCOMP_LOG_TRACE               (1 <<     556 #define SECCOMP_LOG_TRACE               (1 << 4)
964 #define SECCOMP_LOG_LOG                 (1 <<     557 #define SECCOMP_LOG_LOG                 (1 << 5)
965 #define SECCOMP_LOG_ALLOW               (1 <<     558 #define SECCOMP_LOG_ALLOW               (1 << 6)
966 #define SECCOMP_LOG_USER_NOTIF          (1 <<  << 
967                                                   559 
968 static u32 seccomp_actions_logged = SECCOMP_LO    560 static u32 seccomp_actions_logged = SECCOMP_LOG_KILL_PROCESS |
969                                     SECCOMP_LO    561                                     SECCOMP_LOG_KILL_THREAD  |
970                                     SECCOMP_LO    562                                     SECCOMP_LOG_TRAP  |
971                                     SECCOMP_LO    563                                     SECCOMP_LOG_ERRNO |
972                                     SECCOMP_LO << 
973                                     SECCOMP_LO    564                                     SECCOMP_LOG_TRACE |
974                                     SECCOMP_LO    565                                     SECCOMP_LOG_LOG;
975                                                   566 
976 static inline void seccomp_log(unsigned long s    567 static inline void seccomp_log(unsigned long syscall, long signr, u32 action,
977                                bool requested)    568                                bool requested)
978 {                                                 569 {
979         bool log = false;                         570         bool log = false;
980                                                   571 
981         switch (action) {                         572         switch (action) {
982         case SECCOMP_RET_ALLOW:                   573         case SECCOMP_RET_ALLOW:
983                 break;                            574                 break;
984         case SECCOMP_RET_TRAP:                    575         case SECCOMP_RET_TRAP:
985                 log = requested && seccomp_act    576                 log = requested && seccomp_actions_logged & SECCOMP_LOG_TRAP;
986                 break;                            577                 break;
987         case SECCOMP_RET_ERRNO:                   578         case SECCOMP_RET_ERRNO:
988                 log = requested && seccomp_act    579                 log = requested && seccomp_actions_logged & SECCOMP_LOG_ERRNO;
989                 break;                            580                 break;
990         case SECCOMP_RET_TRACE:                   581         case SECCOMP_RET_TRACE:
991                 log = requested && seccomp_act    582                 log = requested && seccomp_actions_logged & SECCOMP_LOG_TRACE;
992                 break;                            583                 break;
993         case SECCOMP_RET_USER_NOTIF:           << 
994                 log = requested && seccomp_act << 
995                 break;                         << 
996         case SECCOMP_RET_LOG:                     584         case SECCOMP_RET_LOG:
997                 log = seccomp_actions_logged &    585                 log = seccomp_actions_logged & SECCOMP_LOG_LOG;
998                 break;                            586                 break;
999         case SECCOMP_RET_KILL_THREAD:             587         case SECCOMP_RET_KILL_THREAD:
1000                 log = seccomp_actions_logged     588                 log = seccomp_actions_logged & SECCOMP_LOG_KILL_THREAD;
1001                 break;                           589                 break;
1002         case SECCOMP_RET_KILL_PROCESS:           590         case SECCOMP_RET_KILL_PROCESS:
1003         default:                                 591         default:
1004                 log = seccomp_actions_logged     592                 log = seccomp_actions_logged & SECCOMP_LOG_KILL_PROCESS;
1005         }                                        593         }
1006                                                  594 
1007         /*                                       595         /*
1008          * Emit an audit message when the act !! 596          * Force an audit message to be emitted when the action is RET_KILL_*,
1009          * FILTER_FLAG_LOG bit was set. The a !! 597          * RET_LOG, or the FILTER_FLAG_LOG bit was set and the action is
1010          * any action from being logged by re !! 598          * allowed to be logged by the admin.
1011          * seccomp_actions_logged sysctl.     << 
1012          */                                      599          */
1013         if (!log)                             !! 600         if (log)
1014                 return;                       !! 601                 return __audit_seccomp(syscall, signr, action);
1015                                                  602 
1016         audit_seccomp(syscall, signr, action) !! 603         /*
                                                   >> 604          * Let the audit subsystem decide if the action should be audited based
                                                   >> 605          * on whether the current task itself is being audited.
                                                   >> 606          */
                                                   >> 607         return audit_seccomp(syscall, signr, action);
1017 }                                                608 }
1018                                                  609 
1019 /*                                               610 /*
1020  * Secure computing mode 1 allows only read/w    611  * Secure computing mode 1 allows only read/write/exit/sigreturn.
1021  * To be fully secure this must be combined w    612  * To be fully secure this must be combined with rlimit
1022  * to limit the stack allocations too.           613  * to limit the stack allocations too.
1023  */                                              614  */
1024 static const int mode1_syscalls[] = {            615 static const int mode1_syscalls[] = {
1025         __NR_seccomp_read, __NR_seccomp_write    616         __NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn,
1026         -1, /* negative terminated */         !! 617         0, /* null terminated */
1027 };                                               618 };
1028                                                  619 
1029 static void __secure_computing_strict(int thi    620 static void __secure_computing_strict(int this_syscall)
1030 {                                                621 {
1031         const int *allowed_syscalls = mode1_s !! 622         const int *syscall_whitelist = mode1_syscalls;
1032 #ifdef CONFIG_COMPAT                             623 #ifdef CONFIG_COMPAT
1033         if (in_compat_syscall())                 624         if (in_compat_syscall())
1034                 allowed_syscalls = get_compat !! 625                 syscall_whitelist = get_compat_mode1_syscalls();
1035 #endif                                           626 #endif
1036         do {                                     627         do {
1037                 if (*allowed_syscalls == this !! 628                 if (*syscall_whitelist == this_syscall)
1038                         return;                  629                         return;
1039         } while (*++allowed_syscalls != -1);  !! 630         } while (*++syscall_whitelist);
1040                                                  631 
1041 #ifdef SECCOMP_DEBUG                             632 #ifdef SECCOMP_DEBUG
1042         dump_stack();                            633         dump_stack();
1043 #endif                                           634 #endif
1044         current->seccomp.mode = SECCOMP_MODE_ << 
1045         seccomp_log(this_syscall, SIGKILL, SE    635         seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true);
1046         do_exit(SIGKILL);                        636         do_exit(SIGKILL);
1047 }                                                637 }
1048                                                  638 
1049 #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER          639 #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER
1050 void secure_computing_strict(int this_syscall    640 void secure_computing_strict(int this_syscall)
1051 {                                                641 {
1052         int mode = current->seccomp.mode;        642         int mode = current->seccomp.mode;
1053                                                  643 
1054         if (IS_ENABLED(CONFIG_CHECKPOINT_REST    644         if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
1055             unlikely(current->ptrace & PT_SUS    645             unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
1056                 return;                          646                 return;
1057                                                  647 
1058         if (mode == SECCOMP_MODE_DISABLED)       648         if (mode == SECCOMP_MODE_DISABLED)
1059                 return;                          649                 return;
1060         else if (mode == SECCOMP_MODE_STRICT)    650         else if (mode == SECCOMP_MODE_STRICT)
1061                 __secure_computing_strict(thi    651                 __secure_computing_strict(this_syscall);
1062         else                                     652         else
1063                 BUG();                           653                 BUG();
1064 }                                                654 }
1065 #else                                            655 #else
1066                                                  656 
1067 #ifdef CONFIG_SECCOMP_FILTER                     657 #ifdef CONFIG_SECCOMP_FILTER
1068 static u64 seccomp_next_notify_id(struct secc << 
1069 {                                             << 
1070         /*                                    << 
1071          * Note: overflow is ok here, the id  << 
1072          * filter.                            << 
1073          */                                   << 
1074         lockdep_assert_held(&filter->notify_l << 
1075         return filter->notif->next_id++;      << 
1076 }                                             << 
1077                                               << 
1078 static void seccomp_handle_addfd(struct secco << 
1079 {                                             << 
1080         int fd;                               << 
1081                                               << 
1082         /*                                    << 
1083          * Remove the notification, and reset << 
1084          * that it has been handled.          << 
1085          */                                   << 
1086         list_del_init(&addfd->list);          << 
1087         if (!addfd->setfd)                    << 
1088                 fd = receive_fd(addfd->file,  << 
1089         else                                  << 
1090                 fd = receive_fd_replace(addfd << 
1091         addfd->ret = fd;                      << 
1092                                               << 
1093         if (addfd->ioctl_flags & SECCOMP_ADDF << 
1094                 /* If we fail reset and retur << 
1095                 if (fd < 0) {                 << 
1096                         n->state = SECCOMP_NO << 
1097                 } else {                      << 
1098                         /* Return the FD we j << 
1099                         n->flags = 0;         << 
1100                         n->error = 0;         << 
1101                         n->val = fd;          << 
1102                 }                             << 
1103         }                                     << 
1104                                               << 
1105         /*                                    << 
1106          * Mark the notification as completed << 
1107          * might be invalidated and we can't  << 
1108          */                                   << 
1109         complete(&addfd->completion);         << 
1110 }                                             << 
1111                                               << 
1112 static bool should_sleep_killable(struct secc << 
1113                                   struct secc << 
1114 {                                             << 
1115         return match->wait_killable_recv && n << 
1116 }                                             << 
1117                                               << 
1118 static int seccomp_do_user_notification(int t << 
1119                                         struc << 
1120                                         const << 
1121 {                                             << 
1122         int err;                              << 
1123         u32 flags = 0;                        << 
1124         long ret = 0;                         << 
1125         struct seccomp_knotif n = {};         << 
1126         struct seccomp_kaddfd *addfd, *tmp;   << 
1127                                               << 
1128         mutex_lock(&match->notify_lock);      << 
1129         err = -ENOSYS;                        << 
1130         if (!match->notif)                    << 
1131                 goto out;                     << 
1132                                               << 
1133         n.task = current;                     << 
1134         n.state = SECCOMP_NOTIFY_INIT;        << 
1135         n.data = sd;                          << 
1136         n.id = seccomp_next_notify_id(match); << 
1137         init_completion(&n.ready);            << 
1138         list_add_tail(&n.list, &match->notif- << 
1139         INIT_LIST_HEAD(&n.addfd);             << 
1140                                               << 
1141         atomic_inc(&match->notif->requests);  << 
1142         if (match->notif->flags & SECCOMP_USE << 
1143                 wake_up_poll_on_current_cpu(& << 
1144         else                                  << 
1145                 wake_up_poll(&match->wqh, EPO << 
1146                                               << 
1147         /*                                    << 
1148          * This is where we wait for a reply  << 
1149          */                                   << 
1150         do {                                  << 
1151                 bool wait_killable = should_s << 
1152                                               << 
1153                 mutex_unlock(&match->notify_l << 
1154                 if (wait_killable)            << 
1155                         err = wait_for_comple << 
1156                 else                          << 
1157                         err = wait_for_comple << 
1158                 mutex_lock(&match->notify_loc << 
1159                                               << 
1160                 if (err != 0) {               << 
1161                         /*                    << 
1162                          * Check to see if th << 
1163                          * whether we should  << 
1164                          */                   << 
1165                         if (!wait_killable && << 
1166                                 continue;     << 
1167                                               << 
1168                         goto interrupted;     << 
1169                 }                             << 
1170                                               << 
1171                 addfd = list_first_entry_or_n << 
1172                                               << 
1173                 /* Check if we were woken up  << 
1174                 if (addfd)                    << 
1175                         seccomp_handle_addfd( << 
1176                                               << 
1177         }  while (n.state != SECCOMP_NOTIFY_R << 
1178                                               << 
1179         ret = n.val;                          << 
1180         err = n.error;                        << 
1181         flags = n.flags;                      << 
1182                                               << 
1183 interrupted:                                  << 
1184         /* If there were any pending addfd ca << 
1185         list_for_each_entry_safe(addfd, tmp,  << 
1186                 /* The process went away befo << 
1187                 addfd->ret = -ESRCH;          << 
1188                 list_del_init(&addfd->list);  << 
1189                 complete(&addfd->completion); << 
1190         }                                     << 
1191                                               << 
1192         /*                                    << 
1193          * Note that it's possible the listen << 
1194          * we were notified of a response (or << 
1195          * re-acquire the lock, so only delet << 
1196          * notification actually exists.      << 
1197          *                                    << 
1198          * Also note that this test is only v << 
1199          * *reattach* to a notifier right now << 
1200          * keep track of the notif itself and << 
1201          */                                   << 
1202         if (match->notif)                     << 
1203                 list_del(&n.list);            << 
1204 out:                                          << 
1205         mutex_unlock(&match->notify_lock);    << 
1206                                               << 
1207         /* Userspace requests to continue the << 
1208         if (flags & SECCOMP_USER_NOTIF_FLAG_C << 
1209                 return 0;                     << 
1210                                               << 
1211         syscall_set_return_value(current, cur << 
1212                                  err, ret);   << 
1213         return -1;                            << 
1214 }                                             << 
1215                                               << 
1216 static int __seccomp_filter(int this_syscall,    658 static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
1217                             const bool rechec    659                             const bool recheck_after_trace)
1218 {                                                660 {
1219         u32 filter_ret, action;                  661         u32 filter_ret, action;
1220         struct seccomp_filter *match = NULL;     662         struct seccomp_filter *match = NULL;
1221         int data;                                663         int data;
1222         struct seccomp_data sd_local;         << 
1223                                                  664 
1224         /*                                       665         /*
1225          * Make sure that any changes to mode    666          * Make sure that any changes to mode from another thread have
1226          * been seen after SYSCALL_WORK_SECCO !! 667          * been seen after TIF_SECCOMP was seen.
1227          */                                      668          */
1228         smp_rmb();                            !! 669         rmb();
1229                                               << 
1230         if (!sd) {                            << 
1231                 populate_seccomp_data(&sd_loc << 
1232                 sd = &sd_local;               << 
1233         }                                     << 
1234                                                  670 
1235         filter_ret = seccomp_run_filters(sd,     671         filter_ret = seccomp_run_filters(sd, &match);
1236         data = filter_ret & SECCOMP_RET_DATA;    672         data = filter_ret & SECCOMP_RET_DATA;
1237         action = filter_ret & SECCOMP_RET_ACT    673         action = filter_ret & SECCOMP_RET_ACTION_FULL;
1238                                                  674 
1239         switch (action) {                        675         switch (action) {
1240         case SECCOMP_RET_ERRNO:                  676         case SECCOMP_RET_ERRNO:
1241                 /* Set low-order bits as an e    677                 /* Set low-order bits as an errno, capped at MAX_ERRNO. */
1242                 if (data > MAX_ERRNO)            678                 if (data > MAX_ERRNO)
1243                         data = MAX_ERRNO;        679                         data = MAX_ERRNO;
1244                 syscall_set_return_value(curr !! 680                 syscall_set_return_value(current, task_pt_regs(current),
1245                                          -dat    681                                          -data, 0);
1246                 goto skip;                       682                 goto skip;
1247                                                  683 
1248         case SECCOMP_RET_TRAP:                   684         case SECCOMP_RET_TRAP:
1249                 /* Show the handler the origi    685                 /* Show the handler the original registers. */
1250                 syscall_rollback(current, cur !! 686                 syscall_rollback(current, task_pt_regs(current));
1251                 /* Let the filter pass back 1    687                 /* Let the filter pass back 16 bits of data. */
1252                 force_sig_seccomp(this_syscal !! 688                 seccomp_send_sigsys(this_syscall, data);
1253                 goto skip;                       689                 goto skip;
1254                                                  690 
1255         case SECCOMP_RET_TRACE:                  691         case SECCOMP_RET_TRACE:
1256                 /* We've been put in this sta    692                 /* We've been put in this state by the ptracer already. */
1257                 if (recheck_after_trace)         693                 if (recheck_after_trace)
1258                         return 0;                694                         return 0;
1259                                                  695 
1260                 /* ENOSYS these calls if ther    696                 /* ENOSYS these calls if there is no tracer attached. */
1261                 if (!ptrace_event_enabled(cur    697                 if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) {
1262                         syscall_set_return_va    698                         syscall_set_return_value(current,
1263                                               !! 699                                                  task_pt_regs(current),
1264                                                  700                                                  -ENOSYS, 0);
1265                         goto skip;               701                         goto skip;
1266                 }                                702                 }
1267                                                  703 
1268                 /* Allow the BPF to provide t    704                 /* Allow the BPF to provide the event message */
1269                 ptrace_event(PTRACE_EVENT_SEC    705                 ptrace_event(PTRACE_EVENT_SECCOMP, data);
1270                 /*                               706                 /*
1271                  * The delivery of a fatal si    707                  * The delivery of a fatal signal during event
1272                  * notification may silently     708                  * notification may silently skip tracer notification,
1273                  * which could leave us with     709                  * which could leave us with a potentially unmodified
1274                  * syscall that the tracer wo    710                  * syscall that the tracer would have liked to have
1275                  * changed. Since the process    711                  * changed. Since the process is about to die, we just
1276                  * force the syscall to be sk    712                  * force the syscall to be skipped and let the signal
1277                  * kill the process and corre    713                  * kill the process and correctly handle any tracer exit
1278                  * notifications.                714                  * notifications.
1279                  */                              715                  */
1280                 if (fatal_signal_pending(curr    716                 if (fatal_signal_pending(current))
1281                         goto skip;               717                         goto skip;
1282                 /* Check if the tracer forced    718                 /* Check if the tracer forced the syscall to be skipped. */
1283                 this_syscall = syscall_get_nr !! 719                 this_syscall = syscall_get_nr(current, task_pt_regs(current));
1284                 if (this_syscall < 0)            720                 if (this_syscall < 0)
1285                         goto skip;               721                         goto skip;
1286                                                  722 
1287                 /*                               723                 /*
1288                  * Recheck the syscall, since    724                  * Recheck the syscall, since it may have changed. This
1289                  * intentionally uses a NULL     725                  * intentionally uses a NULL struct seccomp_data to force
1290                  * a reload of all registers.    726                  * a reload of all registers. This does not goto skip since
1291                  * a skip would have already     727                  * a skip would have already been reported.
1292                  */                              728                  */
1293                 if (__seccomp_filter(this_sys    729                 if (__seccomp_filter(this_syscall, NULL, true))
1294                         return -1;               730                         return -1;
1295                                                  731 
1296                 return 0;                        732                 return 0;
1297                                                  733 
1298         case SECCOMP_RET_USER_NOTIF:          << 
1299                 if (seccomp_do_user_notificat << 
1300                         goto skip;            << 
1301                                               << 
1302                 return 0;                     << 
1303                                               << 
1304         case SECCOMP_RET_LOG:                    734         case SECCOMP_RET_LOG:
1305                 seccomp_log(this_syscall, 0,     735                 seccomp_log(this_syscall, 0, action, true);
1306                 return 0;                        736                 return 0;
1307                                                  737 
1308         case SECCOMP_RET_ALLOW:                  738         case SECCOMP_RET_ALLOW:
1309                 /*                               739                 /*
1310                  * Note that the "match" filt    740                  * Note that the "match" filter will always be NULL for
1311                  * this action since SECCOMP_    741                  * this action since SECCOMP_RET_ALLOW is the starting
1312                  * state in seccomp_run_filte    742                  * state in seccomp_run_filters().
1313                  */                              743                  */
1314                 return 0;                        744                 return 0;
1315                                                  745 
1316         case SECCOMP_RET_KILL_THREAD:            746         case SECCOMP_RET_KILL_THREAD:
1317         case SECCOMP_RET_KILL_PROCESS:           747         case SECCOMP_RET_KILL_PROCESS:
1318         default:                                 748         default:
1319                 current->seccomp.mode = SECCO << 
1320                 seccomp_log(this_syscall, SIG    749                 seccomp_log(this_syscall, SIGSYS, action, true);
1321                 /* Dump core only if this is     750                 /* Dump core only if this is the last remaining thread. */
1322                 if (action != SECCOMP_RET_KIL !! 751                 if (action == SECCOMP_RET_KILL_PROCESS ||
1323                     (atomic_read(&current->si !! 752                     get_nr_threads(current) == 1) {
                                                   >> 753                         siginfo_t info;
                                                   >> 754 
1324                         /* Show the original     755                         /* Show the original registers in the dump. */
1325                         syscall_rollback(curr !! 756                         syscall_rollback(current, task_pt_regs(current));
1326                         /* Trigger a coredump !! 757                         /* Trigger a manual coredump since do_exit skips it. */
1327                         force_sig_seccomp(thi !! 758                         seccomp_init_siginfo(&info, this_syscall, data);
1328                 } else {                      !! 759                         do_coredump(&info);
1329                         do_exit(SIGSYS);      << 
1330                 }                                760                 }
1331                 return -1; /* skip the syscal !! 761                 if (action == SECCOMP_RET_KILL_PROCESS)
                                                   >> 762                         do_group_exit(SIGSYS);
                                                   >> 763                 else
                                                   >> 764                         do_exit(SIGSYS);
1332         }                                        765         }
1333                                                  766 
1334         unreachable();                           767         unreachable();
1335                                                  768 
1336 skip:                                            769 skip:
1337         seccomp_log(this_syscall, 0, action,     770         seccomp_log(this_syscall, 0, action, match ? match->log : false);
1338         return -1;                               771         return -1;
1339 }                                                772 }
1340 #else                                            773 #else
1341 static int __seccomp_filter(int this_syscall,    774 static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
1342                             const bool rechec    775                             const bool recheck_after_trace)
1343 {                                                776 {
1344         BUG();                                   777         BUG();
1345                                               << 
1346         return -1;                            << 
1347 }                                                778 }
1348 #endif                                           779 #endif
1349                                                  780 
1350 int __secure_computing(const struct seccomp_d    781 int __secure_computing(const struct seccomp_data *sd)
1351 {                                                782 {
1352         int mode = current->seccomp.mode;        783         int mode = current->seccomp.mode;
1353         int this_syscall;                        784         int this_syscall;
1354                                                  785 
1355         if (IS_ENABLED(CONFIG_CHECKPOINT_REST    786         if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
1356             unlikely(current->ptrace & PT_SUS    787             unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
1357                 return 0;                        788                 return 0;
1358                                                  789 
1359         this_syscall = sd ? sd->nr :             790         this_syscall = sd ? sd->nr :
1360                 syscall_get_nr(current, curre !! 791                 syscall_get_nr(current, task_pt_regs(current));
1361                                                  792 
1362         switch (mode) {                          793         switch (mode) {
1363         case SECCOMP_MODE_STRICT:                794         case SECCOMP_MODE_STRICT:
1364                 __secure_computing_strict(thi    795                 __secure_computing_strict(this_syscall);  /* may call do_exit */
1365                 return 0;                        796                 return 0;
1366         case SECCOMP_MODE_FILTER:                797         case SECCOMP_MODE_FILTER:
1367                 return __seccomp_filter(this_    798                 return __seccomp_filter(this_syscall, sd, false);
1368         /* Surviving SECCOMP_RET_KILL_* must  << 
1369         case SECCOMP_MODE_DEAD:               << 
1370                 WARN_ON_ONCE(1);              << 
1371                 do_exit(SIGKILL);             << 
1372                 return -1;                    << 
1373         default:                                 799         default:
1374                 BUG();                           800                 BUG();
1375         }                                        801         }
1376 }                                                802 }
1377 #endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */     803 #endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */
1378                                                  804 
1379 long prctl_get_seccomp(void)                     805 long prctl_get_seccomp(void)
1380 {                                                806 {
1381         return current->seccomp.mode;            807         return current->seccomp.mode;
1382 }                                                808 }
1383                                                  809 
1384 /**                                              810 /**
1385  * seccomp_set_mode_strict: internal function    811  * seccomp_set_mode_strict: internal function for setting strict seccomp
1386  *                                               812  *
1387  * Once current->seccomp.mode is non-zero, it    813  * Once current->seccomp.mode is non-zero, it may not be changed.
1388  *                                               814  *
1389  * Returns 0 on success or -EINVAL on failure    815  * Returns 0 on success or -EINVAL on failure.
1390  */                                              816  */
1391 static long seccomp_set_mode_strict(void)        817 static long seccomp_set_mode_strict(void)
1392 {                                                818 {
1393         const unsigned long seccomp_mode = SE    819         const unsigned long seccomp_mode = SECCOMP_MODE_STRICT;
1394         long ret = -EINVAL;                      820         long ret = -EINVAL;
1395                                                  821 
1396         spin_lock_irq(&current->sighand->sigl    822         spin_lock_irq(&current->sighand->siglock);
1397                                                  823 
1398         if (!seccomp_may_assign_mode(seccomp_    824         if (!seccomp_may_assign_mode(seccomp_mode))
1399                 goto out;                        825                 goto out;
1400                                                  826 
1401 #ifdef TIF_NOTSC                                 827 #ifdef TIF_NOTSC
1402         disable_TSC();                           828         disable_TSC();
1403 #endif                                           829 #endif
1404         seccomp_assign_mode(current, seccomp_    830         seccomp_assign_mode(current, seccomp_mode, 0);
1405         ret = 0;                                 831         ret = 0;
1406                                                  832 
1407 out:                                             833 out:
1408         spin_unlock_irq(&current->sighand->si    834         spin_unlock_irq(&current->sighand->siglock);
1409                                                  835 
1410         return ret;                              836         return ret;
1411 }                                                837 }
1412                                                  838 
1413 #ifdef CONFIG_SECCOMP_FILTER                     839 #ifdef CONFIG_SECCOMP_FILTER
1414 static void seccomp_notify_free(struct seccom << 
1415 {                                             << 
1416         kfree(filter->notif);                 << 
1417         filter->notif = NULL;                 << 
1418 }                                             << 
1419                                               << 
1420 static void seccomp_notify_detach(struct secc << 
1421 {                                             << 
1422         struct seccomp_knotif *knotif;        << 
1423                                               << 
1424         if (!filter)                          << 
1425                 return;                       << 
1426                                               << 
1427         mutex_lock(&filter->notify_lock);     << 
1428                                               << 
1429         /*                                    << 
1430          * If this file is being closed becau << 
1431          * died, let's wake everyone up who w << 
1432          */                                   << 
1433         list_for_each_entry(knotif, &filter-> << 
1434                 if (knotif->state == SECCOMP_ << 
1435                         continue;             << 
1436                                               << 
1437                 knotif->state = SECCOMP_NOTIF << 
1438                 knotif->error = -ENOSYS;      << 
1439                 knotif->val = 0;              << 
1440                                               << 
1441                 /*                            << 
1442                  * We do not need to wake up  << 
1443                  * the notifier will do that  << 
1444                  * like a standard reply.     << 
1445                  */                           << 
1446                 complete(&knotif->ready);     << 
1447         }                                     << 
1448                                               << 
1449         seccomp_notify_free(filter);          << 
1450         mutex_unlock(&filter->notify_lock);   << 
1451 }                                             << 
1452                                               << 
1453 static int seccomp_notify_release(struct inod << 
1454 {                                             << 
1455         struct seccomp_filter *filter = file- << 
1456                                               << 
1457         seccomp_notify_detach(filter);        << 
1458         __put_seccomp_filter(filter);         << 
1459         return 0;                             << 
1460 }                                             << 
1461                                               << 
1462 /* must be called with notif_lock held */     << 
1463 static inline struct seccomp_knotif *         << 
1464 find_notification(struct seccomp_filter *filt << 
1465 {                                             << 
1466         struct seccomp_knotif *cur;           << 
1467                                               << 
1468         lockdep_assert_held(&filter->notify_l << 
1469                                               << 
1470         list_for_each_entry(cur, &filter->not << 
1471                 if (cur->id == id)            << 
1472                         return cur;           << 
1473         }                                     << 
1474                                               << 
1475         return NULL;                          << 
1476 }                                             << 
1477                                               << 
1478 static int recv_wake_function(wait_queue_entr << 
1479                                   void *key)  << 
1480 {                                             << 
1481         /* Avoid a wakeup if event not intere << 
1482         if (key && !(key_to_poll(key) & (EPOL << 
1483                 return 0;                     << 
1484         return autoremove_wake_function(wait, << 
1485 }                                             << 
1486                                               << 
1487 static int recv_wait_event(struct seccomp_fil << 
1488 {                                             << 
1489         DEFINE_WAIT_FUNC(wait, recv_wake_func << 
1490         int ret;                              << 
1491                                               << 
1492         if (refcount_read(&filter->users) ==  << 
1493                 return 0;                     << 
1494                                               << 
1495         if (atomic_dec_if_positive(&filter->n << 
1496                 return 0;                     << 
1497                                               << 
1498         for (;;) {                            << 
1499                 ret = prepare_to_wait_event(& << 
1500                                               << 
1501                 if (atomic_dec_if_positive(&f << 
1502                         break;                << 
1503                 if (refcount_read(&filter->us << 
1504                         break;                << 
1505                                               << 
1506                 if (ret)                      << 
1507                         return ret;           << 
1508                                               << 
1509                 schedule();                   << 
1510         }                                     << 
1511         finish_wait(&filter->wqh, &wait);     << 
1512         return 0;                             << 
1513 }                                             << 
1514                                               << 
1515 static long seccomp_notify_recv(struct seccom << 
1516                                 void __user * << 
1517 {                                             << 
1518         struct seccomp_knotif *knotif = NULL, << 
1519         struct seccomp_notif unotif;          << 
1520         ssize_t ret;                          << 
1521                                               << 
1522         /* Verify that we're not given garbag << 
1523         ret = check_zeroed_user(buf, sizeof(u << 
1524         if (ret < 0)                          << 
1525                 return ret;                   << 
1526         if (!ret)                             << 
1527                 return -EINVAL;               << 
1528                                               << 
1529         memset(&unotif, 0, sizeof(unotif));   << 
1530                                               << 
1531         ret = recv_wait_event(filter);        << 
1532         if (ret < 0)                          << 
1533                 return ret;                   << 
1534                                               << 
1535         mutex_lock(&filter->notify_lock);     << 
1536         list_for_each_entry(cur, &filter->not << 
1537                 if (cur->state == SECCOMP_NOT << 
1538                         knotif = cur;         << 
1539                         break;                << 
1540                 }                             << 
1541         }                                     << 
1542                                               << 
1543         /*                                    << 
1544          * If we didn't find a notification,  << 
1545          * interrupted by a fatal signal betw << 
1546          * when we were able to acquire the r << 
1547          */                                   << 
1548         if (!knotif) {                        << 
1549                 ret = -ENOENT;                << 
1550                 goto out;                     << 
1551         }                                     << 
1552                                               << 
1553         unotif.id = knotif->id;               << 
1554         unotif.pid = task_pid_vnr(knotif->tas << 
1555         unotif.data = *(knotif->data);        << 
1556                                               << 
1557         knotif->state = SECCOMP_NOTIFY_SENT;  << 
1558         wake_up_poll(&filter->wqh, EPOLLOUT | << 
1559         ret = 0;                              << 
1560 out:                                          << 
1561         mutex_unlock(&filter->notify_lock);   << 
1562                                               << 
1563         if (ret == 0 && copy_to_user(buf, &un << 
1564                 ret = -EFAULT;                << 
1565                                               << 
1566                 /*                            << 
1567                  * Userspace screwed up. To m << 
1568                  * notification alive, let's  << 
1569                  * may have died when we rele << 
1570                  * sure it's still around.    << 
1571                  */                           << 
1572                 mutex_lock(&filter->notify_lo << 
1573                 knotif = find_notification(fi << 
1574                 if (knotif) {                 << 
1575                         /* Reset the process  << 
1576                         if (should_sleep_kill << 
1577                                 complete(&kno << 
1578                         knotif->state = SECCO << 
1579                         atomic_inc(&filter->n << 
1580                         wake_up_poll(&filter- << 
1581                 }                             << 
1582                 mutex_unlock(&filter->notify_ << 
1583         }                                     << 
1584                                               << 
1585         return ret;                           << 
1586 }                                             << 
1587                                               << 
1588 static long seccomp_notify_send(struct seccom << 
1589                                 void __user * << 
1590 {                                             << 
1591         struct seccomp_notif_resp resp = {};  << 
1592         struct seccomp_knotif *knotif;        << 
1593         long ret;                             << 
1594                                               << 
1595         if (copy_from_user(&resp, buf, sizeof << 
1596                 return -EFAULT;               << 
1597                                               << 
1598         if (resp.flags & ~SECCOMP_USER_NOTIF_ << 
1599                 return -EINVAL;               << 
1600                                               << 
1601         if ((resp.flags & SECCOMP_USER_NOTIF_ << 
1602             (resp.error || resp.val))         << 
1603                 return -EINVAL;               << 
1604                                               << 
1605         ret = mutex_lock_interruptible(&filte << 
1606         if (ret < 0)                          << 
1607                 return ret;                   << 
1608                                               << 
1609         knotif = find_notification(filter, re << 
1610         if (!knotif) {                        << 
1611                 ret = -ENOENT;                << 
1612                 goto out;                     << 
1613         }                                     << 
1614                                               << 
1615         /* Allow exactly one reply. */        << 
1616         if (knotif->state != SECCOMP_NOTIFY_S << 
1617                 ret = -EINPROGRESS;           << 
1618                 goto out;                     << 
1619         }                                     << 
1620                                               << 
1621         ret = 0;                              << 
1622         knotif->state = SECCOMP_NOTIFY_REPLIE << 
1623         knotif->error = resp.error;           << 
1624         knotif->val = resp.val;               << 
1625         knotif->flags = resp.flags;           << 
1626         if (filter->notif->flags & SECCOMP_US << 
1627                 complete_on_current_cpu(&knot << 
1628         else                                  << 
1629                 complete(&knotif->ready);     << 
1630 out:                                          << 
1631         mutex_unlock(&filter->notify_lock);   << 
1632         return ret;                           << 
1633 }                                             << 
1634                                               << 
1635 static long seccomp_notify_id_valid(struct se << 
1636                                     void __us << 
1637 {                                             << 
1638         struct seccomp_knotif *knotif;        << 
1639         u64 id;                               << 
1640         long ret;                             << 
1641                                               << 
1642         if (copy_from_user(&id, buf, sizeof(i << 
1643                 return -EFAULT;               << 
1644                                               << 
1645         ret = mutex_lock_interruptible(&filte << 
1646         if (ret < 0)                          << 
1647                 return ret;                   << 
1648                                               << 
1649         knotif = find_notification(filter, id << 
1650         if (knotif && knotif->state == SECCOM << 
1651                 ret = 0;                      << 
1652         else                                  << 
1653                 ret = -ENOENT;                << 
1654                                               << 
1655         mutex_unlock(&filter->notify_lock);   << 
1656         return ret;                           << 
1657 }                                             << 
1658                                               << 
1659 static long seccomp_notify_set_flags(struct s << 
1660                                     unsigned  << 
1661 {                                             << 
1662         long ret;                             << 
1663                                               << 
1664         if (flags & ~SECCOMP_USER_NOTIF_FD_SY << 
1665                 return -EINVAL;               << 
1666                                               << 
1667         ret = mutex_lock_interruptible(&filte << 
1668         if (ret < 0)                          << 
1669                 return ret;                   << 
1670         filter->notif->flags = flags;         << 
1671         mutex_unlock(&filter->notify_lock);   << 
1672         return 0;                             << 
1673 }                                             << 
1674                                               << 
1675 static long seccomp_notify_addfd(struct secco << 
1676                                  struct secco << 
1677                                  unsigned int << 
1678 {                                             << 
1679         struct seccomp_notif_addfd addfd;     << 
1680         struct seccomp_knotif *knotif;        << 
1681         struct seccomp_kaddfd kaddfd;         << 
1682         int ret;                              << 
1683                                               << 
1684         BUILD_BUG_ON(sizeof(addfd) < SECCOMP_ << 
1685         BUILD_BUG_ON(sizeof(addfd) != SECCOMP << 
1686                                               << 
1687         if (size < SECCOMP_NOTIFY_ADDFD_SIZE_ << 
1688                 return -EINVAL;               << 
1689                                               << 
1690         ret = copy_struct_from_user(&addfd, s << 
1691         if (ret)                              << 
1692                 return ret;                   << 
1693                                               << 
1694         if (addfd.newfd_flags & ~O_CLOEXEC)   << 
1695                 return -EINVAL;               << 
1696                                               << 
1697         if (addfd.flags & ~(SECCOMP_ADDFD_FLA << 
1698                 return -EINVAL;               << 
1699                                               << 
1700         if (addfd.newfd && !(addfd.flags & SE << 
1701                 return -EINVAL;               << 
1702                                               << 
1703         kaddfd.file = fget(addfd.srcfd);      << 
1704         if (!kaddfd.file)                     << 
1705                 return -EBADF;                << 
1706                                               << 
1707         kaddfd.ioctl_flags = addfd.flags;     << 
1708         kaddfd.flags = addfd.newfd_flags;     << 
1709         kaddfd.setfd = addfd.flags & SECCOMP_ << 
1710         kaddfd.fd = addfd.newfd;              << 
1711         init_completion(&kaddfd.completion);  << 
1712                                               << 
1713         ret = mutex_lock_interruptible(&filte << 
1714         if (ret < 0)                          << 
1715                 goto out;                     << 
1716                                               << 
1717         knotif = find_notification(filter, ad << 
1718         if (!knotif) {                        << 
1719                 ret = -ENOENT;                << 
1720                 goto out_unlock;              << 
1721         }                                     << 
1722                                               << 
1723         /*                                    << 
1724          * We do not want to allow for FD inj << 
1725          * notification has been picked up by << 
1726          * the notification has been replied  << 
1727          */                                   << 
1728         if (knotif->state != SECCOMP_NOTIFY_S << 
1729                 ret = -EINPROGRESS;           << 
1730                 goto out_unlock;              << 
1731         }                                     << 
1732                                               << 
1733         if (addfd.flags & SECCOMP_ADDFD_FLAG_ << 
1734                 /*                            << 
1735                  * Disallow queuing an atomic << 
1736                  * some addfd requests still  << 
1737                  *                            << 
1738                  * There is no clear reason t << 
1739                  * the loop on the other side << 
1740                  */                           << 
1741                 if (!list_empty(&knotif->addf << 
1742                         ret = -EBUSY;         << 
1743                         goto out_unlock;      << 
1744                 }                             << 
1745                                               << 
1746                 /* Allow exactly only one rep << 
1747                 knotif->state = SECCOMP_NOTIF << 
1748         }                                     << 
1749                                               << 
1750         list_add(&kaddfd.list, &knotif->addfd << 
1751         complete(&knotif->ready);             << 
1752         mutex_unlock(&filter->notify_lock);   << 
1753                                               << 
1754         /* Now we wait for it to be processed << 
1755         ret = wait_for_completion_interruptib << 
1756         if (ret == 0) {                       << 
1757                 /*                            << 
1758                  * We had a successful comple << 
1759                  * removed us from the addfd  << 
1760                  * wait_for_completion_interr << 
1761                  * success that lets us read  << 
1762                  * locking.                   << 
1763                  */                           << 
1764                 ret = kaddfd.ret;             << 
1765                 goto out;                     << 
1766         }                                     << 
1767                                               << 
1768         mutex_lock(&filter->notify_lock);     << 
1769         /*                                    << 
1770          * Even though we were woken up by a  << 
1771          * completion, a completion may have  << 
1772          *                                    << 
1773          * We need to check again if the addf << 
1774          * and if not, we will remove it from << 
1775          */                                   << 
1776         if (list_empty(&kaddfd.list))         << 
1777                 ret = kaddfd.ret;             << 
1778         else                                  << 
1779                 list_del(&kaddfd.list);       << 
1780                                               << 
1781 out_unlock:                                   << 
1782         mutex_unlock(&filter->notify_lock);   << 
1783 out:                                          << 
1784         fput(kaddfd.file);                    << 
1785                                               << 
1786         return ret;                           << 
1787 }                                             << 
1788                                               << 
1789 static long seccomp_notify_ioctl(struct file  << 
1790                                  unsigned lon << 
1791 {                                             << 
1792         struct seccomp_filter *filter = file- << 
1793         void __user *buf = (void __user *)arg << 
1794                                               << 
1795         /* Fixed-size ioctls */               << 
1796         switch (cmd) {                        << 
1797         case SECCOMP_IOCTL_NOTIF_RECV:        << 
1798                 return seccomp_notify_recv(fi << 
1799         case SECCOMP_IOCTL_NOTIF_SEND:        << 
1800                 return seccomp_notify_send(fi << 
1801         case SECCOMP_IOCTL_NOTIF_ID_VALID_WRO << 
1802         case SECCOMP_IOCTL_NOTIF_ID_VALID:    << 
1803                 return seccomp_notify_id_vali << 
1804         case SECCOMP_IOCTL_NOTIF_SET_FLAGS:   << 
1805                 return seccomp_notify_set_fla << 
1806         }                                     << 
1807                                               << 
1808         /* Extensible Argument ioctls */      << 
1809 #define EA_IOCTL(cmd)   ((cmd) & ~(IOC_INOUT  << 
1810         switch (EA_IOCTL(cmd)) {              << 
1811         case EA_IOCTL(SECCOMP_IOCTL_NOTIF_ADD << 
1812                 return seccomp_notify_addfd(f << 
1813         default:                              << 
1814                 return -EINVAL;               << 
1815         }                                     << 
1816 }                                             << 
1817                                               << 
1818 static __poll_t seccomp_notify_poll(struct fi << 
1819                                     struct po << 
1820 {                                             << 
1821         struct seccomp_filter *filter = file- << 
1822         __poll_t ret = 0;                     << 
1823         struct seccomp_knotif *cur;           << 
1824                                               << 
1825         poll_wait(file, &filter->wqh, poll_ta << 
1826                                               << 
1827         if (mutex_lock_interruptible(&filter- << 
1828                 return EPOLLERR;              << 
1829                                               << 
1830         list_for_each_entry(cur, &filter->not << 
1831                 if (cur->state == SECCOMP_NOT << 
1832                         ret |= EPOLLIN | EPOL << 
1833                 if (cur->state == SECCOMP_NOT << 
1834                         ret |= EPOLLOUT | EPO << 
1835                 if ((ret & EPOLLIN) && (ret & << 
1836                         break;                << 
1837         }                                     << 
1838                                               << 
1839         mutex_unlock(&filter->notify_lock);   << 
1840                                               << 
1841         if (refcount_read(&filter->users) ==  << 
1842                 ret |= EPOLLHUP;              << 
1843                                               << 
1844         return ret;                           << 
1845 }                                             << 
1846                                               << 
1847 static const struct file_operations seccomp_n << 
1848         .poll = seccomp_notify_poll,          << 
1849         .release = seccomp_notify_release,    << 
1850         .unlocked_ioctl = seccomp_notify_ioct << 
1851         .compat_ioctl = seccomp_notify_ioctl, << 
1852 };                                            << 
1853                                               << 
1854 static struct file *init_listener(struct secc << 
1855 {                                             << 
1856         struct file *ret;                     << 
1857                                               << 
1858         ret = ERR_PTR(-ENOMEM);               << 
1859         filter->notif = kzalloc(sizeof(*(filt << 
1860         if (!filter->notif)                   << 
1861                 goto out;                     << 
1862                                               << 
1863         filter->notif->next_id = get_random_u << 
1864         INIT_LIST_HEAD(&filter->notif->notifi << 
1865                                               << 
1866         ret = anon_inode_getfile("seccomp not << 
1867                                  filter, O_RD << 
1868         if (IS_ERR(ret))                      << 
1869                 goto out_notif;               << 
1870                                               << 
1871         /* The file has a reference to it now << 
1872         __get_seccomp_filter(filter);         << 
1873                                               << 
1874 out_notif:                                    << 
1875         if (IS_ERR(ret))                      << 
1876                 seccomp_notify_free(filter);  << 
1877 out:                                          << 
1878         return ret;                           << 
1879 }                                             << 
1880                                               << 
1881 /*                                            << 
1882  * Does @new_child have a listener while an a << 
1883  * If so, we'll want to reject this filter.   << 
1884  * This only has to be tested for the current << 
1885  * because TSYNC installs @child with the sam << 
1886  * Note that @new_child is not hooked up to i << 
1887  * we use current->seccomp.filter.            << 
1888  */                                           << 
1889 static bool has_duplicate_listener(struct sec << 
1890 {                                             << 
1891         struct seccomp_filter *cur;           << 
1892                                               << 
1893         /* must be protected against concurre << 
1894         lockdep_assert_held(&current->sighand << 
1895                                               << 
1896         if (!new_child->notif)                << 
1897                 return false;                 << 
1898         for (cur = current->seccomp.filter; c << 
1899                 if (cur->notif)               << 
1900                         return true;          << 
1901         }                                     << 
1902                                               << 
1903         return false;                         << 
1904 }                                             << 
1905                                               << 
1906 /**                                              840 /**
1907  * seccomp_set_mode_filter: internal function    841  * seccomp_set_mode_filter: internal function for setting seccomp filter
1908  * @flags:  flags to change filter behavior      842  * @flags:  flags to change filter behavior
1909  * @filter: struct sock_fprog containing filt    843  * @filter: struct sock_fprog containing filter
1910  *                                               844  *
1911  * This function may be called repeatedly to     845  * This function may be called repeatedly to install additional filters.
1912  * Every filter successfully installed will b    846  * Every filter successfully installed will be evaluated (in reverse order)
1913  * for each system call the task makes.          847  * for each system call the task makes.
1914  *                                               848  *
1915  * Once current->seccomp.mode is non-zero, it    849  * Once current->seccomp.mode is non-zero, it may not be changed.
1916  *                                               850  *
1917  * Returns 0 on success or -EINVAL on failure    851  * Returns 0 on success or -EINVAL on failure.
1918  */                                              852  */
1919 static long seccomp_set_mode_filter(unsigned     853 static long seccomp_set_mode_filter(unsigned int flags,
1920                                     const cha    854                                     const char __user *filter)
1921 {                                                855 {
1922         const unsigned long seccomp_mode = SE    856         const unsigned long seccomp_mode = SECCOMP_MODE_FILTER;
1923         struct seccomp_filter *prepared = NUL    857         struct seccomp_filter *prepared = NULL;
1924         long ret = -EINVAL;                      858         long ret = -EINVAL;
1925         int listener = -1;                    << 
1926         struct file *listener_f = NULL;       << 
1927                                                  859 
1928         /* Validate flags. */                    860         /* Validate flags. */
1929         if (flags & ~SECCOMP_FILTER_FLAG_MASK    861         if (flags & ~SECCOMP_FILTER_FLAG_MASK)
1930                 return -EINVAL;                  862                 return -EINVAL;
1931                                                  863 
1932         /*                                    << 
1933          * In the successful case, NEW_LISTEN << 
1934          * But in the failure case, TSYNC ret << 
1935          * combine these two flags, there's n << 
1936          * succeeded or failed. So, let's dis << 
1937          * has not explicitly requested no er << 
1938          */                                   << 
1939         if ((flags & SECCOMP_FILTER_FLAG_TSYN << 
1940             (flags & SECCOMP_FILTER_FLAG_NEW_ << 
1941             ((flags & SECCOMP_FILTER_FLAG_TSY << 
1942                 return -EINVAL;               << 
1943                                               << 
1944         /*                                    << 
1945          * The SECCOMP_FILTER_FLAG_WAIT_KILLA << 
1946          * without the SECCOMP_FILTER_FLAG_NE << 
1947          */                                   << 
1948         if ((flags & SECCOMP_FILTER_FLAG_WAIT << 
1949             ((flags & SECCOMP_FILTER_FLAG_NEW << 
1950                 return -EINVAL;               << 
1951                                               << 
1952         /* Prepare the new filter before hold    864         /* Prepare the new filter before holding any locks. */
1953         prepared = seccomp_prepare_user_filte    865         prepared = seccomp_prepare_user_filter(filter);
1954         if (IS_ERR(prepared))                    866         if (IS_ERR(prepared))
1955                 return PTR_ERR(prepared);        867                 return PTR_ERR(prepared);
1956                                                  868 
1957         if (flags & SECCOMP_FILTER_FLAG_NEW_L << 
1958                 listener = get_unused_fd_flag << 
1959                 if (listener < 0) {           << 
1960                         ret = listener;       << 
1961                         goto out_free;        << 
1962                 }                             << 
1963                                               << 
1964                 listener_f = init_listener(pr << 
1965                 if (IS_ERR(listener_f)) {     << 
1966                         put_unused_fd(listene << 
1967                         ret = PTR_ERR(listene << 
1968                         goto out_free;        << 
1969                 }                             << 
1970         }                                     << 
1971                                               << 
1972         /*                                       869         /*
1973          * Make sure we cannot change seccomp    870          * Make sure we cannot change seccomp or nnp state via TSYNC
1974          * while another thread is in the mid    871          * while another thread is in the middle of calling exec.
1975          */                                      872          */
1976         if (flags & SECCOMP_FILTER_FLAG_TSYNC    873         if (flags & SECCOMP_FILTER_FLAG_TSYNC &&
1977             mutex_lock_killable(&current->sig    874             mutex_lock_killable(&current->signal->cred_guard_mutex))
1978                 goto out_put_fd;              !! 875                 goto out_free;
1979                                                  876 
1980         spin_lock_irq(&current->sighand->sigl    877         spin_lock_irq(&current->sighand->siglock);
1981                                                  878 
1982         if (!seccomp_may_assign_mode(seccomp_    879         if (!seccomp_may_assign_mode(seccomp_mode))
1983                 goto out;                        880                 goto out;
1984                                                  881 
1985         if (has_duplicate_listener(prepared)) << 
1986                 ret = -EBUSY;                 << 
1987                 goto out;                     << 
1988         }                                     << 
1989                                               << 
1990         ret = seccomp_attach_filter(flags, pr    882         ret = seccomp_attach_filter(flags, prepared);
1991         if (ret)                                 883         if (ret)
1992                 goto out;                        884                 goto out;
1993         /* Do not free the successfully attac    885         /* Do not free the successfully attached filter. */
1994         prepared = NULL;                         886         prepared = NULL;
1995                                                  887 
1996         seccomp_assign_mode(current, seccomp_    888         seccomp_assign_mode(current, seccomp_mode, flags);
1997 out:                                             889 out:
1998         spin_unlock_irq(&current->sighand->si    890         spin_unlock_irq(&current->sighand->siglock);
1999         if (flags & SECCOMP_FILTER_FLAG_TSYNC    891         if (flags & SECCOMP_FILTER_FLAG_TSYNC)
2000                 mutex_unlock(&current->signal    892                 mutex_unlock(&current->signal->cred_guard_mutex);
2001 out_put_fd:                                   << 
2002         if (flags & SECCOMP_FILTER_FLAG_NEW_L << 
2003                 if (ret) {                    << 
2004                         listener_f->private_d << 
2005                         fput(listener_f);     << 
2006                         put_unused_fd(listene << 
2007                         seccomp_notify_detach << 
2008                 } else {                      << 
2009                         fd_install(listener,  << 
2010                         ret = listener;       << 
2011                 }                             << 
2012         }                                     << 
2013 out_free:                                        893 out_free:
2014         seccomp_filter_free(prepared);           894         seccomp_filter_free(prepared);
2015         return ret;                              895         return ret;
2016 }                                                896 }
2017 #else                                            897 #else
2018 static inline long seccomp_set_mode_filter(un    898 static inline long seccomp_set_mode_filter(unsigned int flags,
2019                                            co    899                                            const char __user *filter)
2020 {                                                900 {
2021         return -EINVAL;                          901         return -EINVAL;
2022 }                                                902 }
2023 #endif                                           903 #endif
2024                                                  904 
2025 static long seccomp_get_action_avail(const ch    905 static long seccomp_get_action_avail(const char __user *uaction)
2026 {                                                906 {
2027         u32 action;                              907         u32 action;
2028                                                  908 
2029         if (copy_from_user(&action, uaction,     909         if (copy_from_user(&action, uaction, sizeof(action)))
2030                 return -EFAULT;                  910                 return -EFAULT;
2031                                                  911 
2032         switch (action) {                        912         switch (action) {
2033         case SECCOMP_RET_KILL_PROCESS:           913         case SECCOMP_RET_KILL_PROCESS:
2034         case SECCOMP_RET_KILL_THREAD:            914         case SECCOMP_RET_KILL_THREAD:
2035         case SECCOMP_RET_TRAP:                   915         case SECCOMP_RET_TRAP:
2036         case SECCOMP_RET_ERRNO:                  916         case SECCOMP_RET_ERRNO:
2037         case SECCOMP_RET_USER_NOTIF:          << 
2038         case SECCOMP_RET_TRACE:                  917         case SECCOMP_RET_TRACE:
2039         case SECCOMP_RET_LOG:                    918         case SECCOMP_RET_LOG:
2040         case SECCOMP_RET_ALLOW:                  919         case SECCOMP_RET_ALLOW:
2041                 break;                           920                 break;
2042         default:                                 921         default:
2043                 return -EOPNOTSUPP;              922                 return -EOPNOTSUPP;
2044         }                                        923         }
2045                                                  924 
2046         return 0;                                925         return 0;
2047 }                                                926 }
2048                                                  927 
2049 static long seccomp_get_notif_sizes(void __us << 
2050 {                                             << 
2051         struct seccomp_notif_sizes sizes = {  << 
2052                 .seccomp_notif = sizeof(struc << 
2053                 .seccomp_notif_resp = sizeof( << 
2054                 .seccomp_data = sizeof(struct << 
2055         };                                    << 
2056                                               << 
2057         if (copy_to_user(usizes, &sizes, size << 
2058                 return -EFAULT;               << 
2059                                               << 
2060         return 0;                             << 
2061 }                                             << 
2062                                               << 
2063 /* Common entry point for both prctl and sysc    928 /* Common entry point for both prctl and syscall. */
2064 static long do_seccomp(unsigned int op, unsig    929 static long do_seccomp(unsigned int op, unsigned int flags,
2065                        void __user *uargs)    !! 930                        const char __user *uargs)
2066 {                                                931 {
2067         switch (op) {                            932         switch (op) {
2068         case SECCOMP_SET_MODE_STRICT:            933         case SECCOMP_SET_MODE_STRICT:
2069                 if (flags != 0 || uargs != NU    934                 if (flags != 0 || uargs != NULL)
2070                         return -EINVAL;          935                         return -EINVAL;
2071                 return seccomp_set_mode_stric    936                 return seccomp_set_mode_strict();
2072         case SECCOMP_SET_MODE_FILTER:            937         case SECCOMP_SET_MODE_FILTER:
2073                 return seccomp_set_mode_filte    938                 return seccomp_set_mode_filter(flags, uargs);
2074         case SECCOMP_GET_ACTION_AVAIL:           939         case SECCOMP_GET_ACTION_AVAIL:
2075                 if (flags != 0)                  940                 if (flags != 0)
2076                         return -EINVAL;          941                         return -EINVAL;
2077                                                  942 
2078                 return seccomp_get_action_ava    943                 return seccomp_get_action_avail(uargs);
2079         case SECCOMP_GET_NOTIF_SIZES:         << 
2080                 if (flags != 0)               << 
2081                         return -EINVAL;       << 
2082                                               << 
2083                 return seccomp_get_notif_size << 
2084         default:                                 944         default:
2085                 return -EINVAL;                  945                 return -EINVAL;
2086         }                                        946         }
2087 }                                                947 }
2088                                                  948 
2089 SYSCALL_DEFINE3(seccomp, unsigned int, op, un    949 SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags,
2090                          void __user *, uargs !! 950                          const char __user *, uargs)
2091 {                                                951 {
2092         return do_seccomp(op, flags, uargs);     952         return do_seccomp(op, flags, uargs);
2093 }                                                953 }
2094                                                  954 
2095 /**                                              955 /**
2096  * prctl_set_seccomp: configures current->sec    956  * prctl_set_seccomp: configures current->seccomp.mode
2097  * @seccomp_mode: requested mode to use          957  * @seccomp_mode: requested mode to use
2098  * @filter: optional struct sock_fprog for us    958  * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER
2099  *                                               959  *
2100  * Returns 0 on success or -EINVAL on failure    960  * Returns 0 on success or -EINVAL on failure.
2101  */                                              961  */
2102 long prctl_set_seccomp(unsigned long seccomp_ !! 962 long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter)
2103 {                                                963 {
2104         unsigned int op;                         964         unsigned int op;
2105         void __user *uargs;                   !! 965         char __user *uargs;
2106                                                  966 
2107         switch (seccomp_mode) {                  967         switch (seccomp_mode) {
2108         case SECCOMP_MODE_STRICT:                968         case SECCOMP_MODE_STRICT:
2109                 op = SECCOMP_SET_MODE_STRICT;    969                 op = SECCOMP_SET_MODE_STRICT;
2110                 /*                               970                 /*
2111                  * Setting strict mode throug    971                  * Setting strict mode through prctl always ignored filter,
2112                  * so make sure it is always     972                  * so make sure it is always NULL here to pass the internal
2113                  * check in do_seccomp().        973                  * check in do_seccomp().
2114                  */                              974                  */
2115                 uargs = NULL;                    975                 uargs = NULL;
2116                 break;                           976                 break;
2117         case SECCOMP_MODE_FILTER:                977         case SECCOMP_MODE_FILTER:
2118                 op = SECCOMP_SET_MODE_FILTER;    978                 op = SECCOMP_SET_MODE_FILTER;
2119                 uargs = filter;                  979                 uargs = filter;
2120                 break;                           980                 break;
2121         default:                                 981         default:
2122                 return -EINVAL;                  982                 return -EINVAL;
2123         }                                        983         }
2124                                                  984 
2125         /* prctl interface doesn't have flags    985         /* prctl interface doesn't have flags, so they are always zero. */
2126         return do_seccomp(op, 0, uargs);         986         return do_seccomp(op, 0, uargs);
2127 }                                                987 }
2128                                                  988 
2129 #if defined(CONFIG_SECCOMP_FILTER) && defined    989 #if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE)
2130 static struct seccomp_filter *get_nth_filter(    990 static struct seccomp_filter *get_nth_filter(struct task_struct *task,
2131                                                  991                                              unsigned long filter_off)
2132 {                                                992 {
2133         struct seccomp_filter *orig, *filter;    993         struct seccomp_filter *orig, *filter;
2134         unsigned long count;                     994         unsigned long count;
2135                                                  995 
2136         /*                                       996         /*
2137          * Note: this is only correct because    997          * Note: this is only correct because the caller should be the (ptrace)
2138          * tracer of the task, otherwise lock    998          * tracer of the task, otherwise lock_task_sighand is needed.
2139          */                                      999          */
2140         spin_lock_irq(&task->sighand->siglock    1000         spin_lock_irq(&task->sighand->siglock);
2141                                                  1001 
2142         if (task->seccomp.mode != SECCOMP_MOD    1002         if (task->seccomp.mode != SECCOMP_MODE_FILTER) {
2143                 spin_unlock_irq(&task->sighan    1003                 spin_unlock_irq(&task->sighand->siglock);
2144                 return ERR_PTR(-EINVAL);         1004                 return ERR_PTR(-EINVAL);
2145         }                                        1005         }
2146                                                  1006 
2147         orig = task->seccomp.filter;             1007         orig = task->seccomp.filter;
2148         __get_seccomp_filter(orig);              1008         __get_seccomp_filter(orig);
2149         spin_unlock_irq(&task->sighand->siglo    1009         spin_unlock_irq(&task->sighand->siglock);
2150                                                  1010 
2151         count = 0;                               1011         count = 0;
2152         for (filter = orig; filter; filter =     1012         for (filter = orig; filter; filter = filter->prev)
2153                 count++;                         1013                 count++;
2154                                                  1014 
2155         if (filter_off >= count) {               1015         if (filter_off >= count) {
2156                 filter = ERR_PTR(-ENOENT);       1016                 filter = ERR_PTR(-ENOENT);
2157                 goto out;                        1017                 goto out;
2158         }                                        1018         }
2159                                                  1019 
2160         count -= filter_off;                     1020         count -= filter_off;
2161         for (filter = orig; filter && count >    1021         for (filter = orig; filter && count > 1; filter = filter->prev)
2162                 count--;                         1022                 count--;
2163                                                  1023 
2164         if (WARN_ON(count != 1 || !filter)) {    1024         if (WARN_ON(count != 1 || !filter)) {
2165                 filter = ERR_PTR(-ENOENT);       1025                 filter = ERR_PTR(-ENOENT);
2166                 goto out;                        1026                 goto out;
2167         }                                        1027         }
2168                                                  1028 
2169         __get_seccomp_filter(filter);            1029         __get_seccomp_filter(filter);
2170                                                  1030 
2171 out:                                             1031 out:
2172         __put_seccomp_filter(orig);              1032         __put_seccomp_filter(orig);
2173         return filter;                           1033         return filter;
2174 }                                                1034 }
2175                                                  1035 
2176 long seccomp_get_filter(struct task_struct *t    1036 long seccomp_get_filter(struct task_struct *task, unsigned long filter_off,
2177                         void __user *data)       1037                         void __user *data)
2178 {                                                1038 {
2179         struct seccomp_filter *filter;           1039         struct seccomp_filter *filter;
2180         struct sock_fprog_kern *fprog;           1040         struct sock_fprog_kern *fprog;
2181         long ret;                                1041         long ret;
2182                                                  1042 
2183         if (!capable(CAP_SYS_ADMIN) ||           1043         if (!capable(CAP_SYS_ADMIN) ||
2184             current->seccomp.mode != SECCOMP_    1044             current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2185                 return -EACCES;                  1045                 return -EACCES;
2186         }                                        1046         }
2187                                                  1047 
2188         filter = get_nth_filter(task, filter_    1048         filter = get_nth_filter(task, filter_off);
2189         if (IS_ERR(filter))                      1049         if (IS_ERR(filter))
2190                 return PTR_ERR(filter);          1050                 return PTR_ERR(filter);
2191                                                  1051 
2192         fprog = filter->prog->orig_prog;         1052         fprog = filter->prog->orig_prog;
2193         if (!fprog) {                            1053         if (!fprog) {
2194                 /* This must be a new non-cBP    1054                 /* This must be a new non-cBPF filter, since we save
2195                  * every cBPF filter's orig_p    1055                  * every cBPF filter's orig_prog above when
2196                  * CONFIG_CHECKPOINT_RESTORE     1056                  * CONFIG_CHECKPOINT_RESTORE is enabled.
2197                  */                              1057                  */
2198                 ret = -EMEDIUMTYPE;              1058                 ret = -EMEDIUMTYPE;
2199                 goto out;                        1059                 goto out;
2200         }                                        1060         }
2201                                                  1061 
2202         ret = fprog->len;                        1062         ret = fprog->len;
2203         if (!data)                               1063         if (!data)
2204                 goto out;                        1064                 goto out;
2205                                                  1065 
2206         if (copy_to_user(data, fprog->filter,    1066         if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog)))
2207                 ret = -EFAULT;                   1067                 ret = -EFAULT;
2208                                                  1068 
2209 out:                                             1069 out:
2210         __put_seccomp_filter(filter);            1070         __put_seccomp_filter(filter);
2211         return ret;                              1071         return ret;
2212 }                                                1072 }
2213                                                  1073 
2214 long seccomp_get_metadata(struct task_struct     1074 long seccomp_get_metadata(struct task_struct *task,
2215                           unsigned long size,    1075                           unsigned long size, void __user *data)
2216 {                                                1076 {
2217         long ret;                                1077         long ret;
2218         struct seccomp_filter *filter;           1078         struct seccomp_filter *filter;
2219         struct seccomp_metadata kmd = {};        1079         struct seccomp_metadata kmd = {};
2220                                                  1080 
2221         if (!capable(CAP_SYS_ADMIN) ||           1081         if (!capable(CAP_SYS_ADMIN) ||
2222             current->seccomp.mode != SECCOMP_    1082             current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2223                 return -EACCES;                  1083                 return -EACCES;
2224         }                                        1084         }
2225                                                  1085 
2226         size = min_t(unsigned long, size, siz    1086         size = min_t(unsigned long, size, sizeof(kmd));
2227                                                  1087 
2228         if (size < sizeof(kmd.filter_off))       1088         if (size < sizeof(kmd.filter_off))
2229                 return -EINVAL;                  1089                 return -EINVAL;
2230                                                  1090 
2231         if (copy_from_user(&kmd.filter_off, d    1091         if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off)))
2232                 return -EFAULT;                  1092                 return -EFAULT;
2233                                                  1093 
2234         filter = get_nth_filter(task, kmd.fil    1094         filter = get_nth_filter(task, kmd.filter_off);
2235         if (IS_ERR(filter))                      1095         if (IS_ERR(filter))
2236                 return PTR_ERR(filter);          1096                 return PTR_ERR(filter);
2237                                                  1097 
2238         if (filter->log)                         1098         if (filter->log)
2239                 kmd.flags |= SECCOMP_FILTER_F    1099                 kmd.flags |= SECCOMP_FILTER_FLAG_LOG;
2240                                                  1100 
2241         ret = size;                              1101         ret = size;
2242         if (copy_to_user(data, &kmd, size))      1102         if (copy_to_user(data, &kmd, size))
2243                 ret = -EFAULT;                   1103                 ret = -EFAULT;
2244                                                  1104 
2245         __put_seccomp_filter(filter);            1105         __put_seccomp_filter(filter);
2246         return ret;                              1106         return ret;
2247 }                                                1107 }
2248 #endif                                           1108 #endif
2249                                                  1109 
2250 #ifdef CONFIG_SYSCTL                             1110 #ifdef CONFIG_SYSCTL
2251                                                  1111 
2252 /* Human readable action names for friendly s    1112 /* Human readable action names for friendly sysctl interaction */
2253 #define SECCOMP_RET_KILL_PROCESS_NAME   "kill    1113 #define SECCOMP_RET_KILL_PROCESS_NAME   "kill_process"
2254 #define SECCOMP_RET_KILL_THREAD_NAME    "kill    1114 #define SECCOMP_RET_KILL_THREAD_NAME    "kill_thread"
2255 #define SECCOMP_RET_TRAP_NAME           "trap    1115 #define SECCOMP_RET_TRAP_NAME           "trap"
2256 #define SECCOMP_RET_ERRNO_NAME          "errn    1116 #define SECCOMP_RET_ERRNO_NAME          "errno"
2257 #define SECCOMP_RET_USER_NOTIF_NAME     "user << 
2258 #define SECCOMP_RET_TRACE_NAME          "trac    1117 #define SECCOMP_RET_TRACE_NAME          "trace"
2259 #define SECCOMP_RET_LOG_NAME            "log"    1118 #define SECCOMP_RET_LOG_NAME            "log"
2260 #define SECCOMP_RET_ALLOW_NAME          "allo    1119 #define SECCOMP_RET_ALLOW_NAME          "allow"
2261                                                  1120 
2262 static const char seccomp_actions_avail[] =      1121 static const char seccomp_actions_avail[] =
2263                                 SECCOMP_RET_K    1122                                 SECCOMP_RET_KILL_PROCESS_NAME   " "
2264                                 SECCOMP_RET_K    1123                                 SECCOMP_RET_KILL_THREAD_NAME    " "
2265                                 SECCOMP_RET_T    1124                                 SECCOMP_RET_TRAP_NAME           " "
2266                                 SECCOMP_RET_E    1125                                 SECCOMP_RET_ERRNO_NAME          " "
2267                                 SECCOMP_RET_U << 
2268                                 SECCOMP_RET_T    1126                                 SECCOMP_RET_TRACE_NAME          " "
2269                                 SECCOMP_RET_L    1127                                 SECCOMP_RET_LOG_NAME            " "
2270                                 SECCOMP_RET_A    1128                                 SECCOMP_RET_ALLOW_NAME;
2271                                                  1129 
2272 struct seccomp_log_name {                        1130 struct seccomp_log_name {
2273         u32             log;                     1131         u32             log;
2274         const char      *name;                   1132         const char      *name;
2275 };                                               1133 };
2276                                                  1134 
2277 static const struct seccomp_log_name seccomp_    1135 static const struct seccomp_log_name seccomp_log_names[] = {
2278         { SECCOMP_LOG_KILL_PROCESS, SECCOMP_R    1136         { SECCOMP_LOG_KILL_PROCESS, SECCOMP_RET_KILL_PROCESS_NAME },
2279         { SECCOMP_LOG_KILL_THREAD, SECCOMP_RE    1137         { SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME },
2280         { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_    1138         { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME },
2281         { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRN    1139         { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME },
2282         { SECCOMP_LOG_USER_NOTIF, SECCOMP_RET << 
2283         { SECCOMP_LOG_TRACE, SECCOMP_RET_TRAC    1140         { SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME },
2284         { SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NA    1141         { SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NAME },
2285         { SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLO    1142         { SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLOW_NAME },
2286         { }                                      1143         { }
2287 };                                               1144 };
2288                                                  1145 
2289 static bool seccomp_names_from_actions_logged    1146 static bool seccomp_names_from_actions_logged(char *names, size_t size,
2290                                               !! 1147                                               u32 actions_logged)
2291                                               << 
2292 {                                                1148 {
2293         const struct seccomp_log_name *cur;      1149         const struct seccomp_log_name *cur;
2294         bool append_sep = false;              !! 1150         bool append_space = false;
2295                                                  1151 
2296         for (cur = seccomp_log_names; cur->na    1152         for (cur = seccomp_log_names; cur->name && size; cur++) {
2297                 ssize_t ret;                     1153                 ssize_t ret;
2298                                                  1154 
2299                 if (!(actions_logged & cur->l    1155                 if (!(actions_logged & cur->log))
2300                         continue;                1156                         continue;
2301                                                  1157 
2302                 if (append_sep) {             !! 1158                 if (append_space) {
2303                         ret = strscpy(names,  !! 1159                         ret = strscpy(names, " ", size);
2304                         if (ret < 0)             1160                         if (ret < 0)
2305                                 return false;    1161                                 return false;
2306                                                  1162 
2307                         names += ret;            1163                         names += ret;
2308                         size -= ret;             1164                         size -= ret;
2309                 } else                           1165                 } else
2310                         append_sep = true;    !! 1166                         append_space = true;
2311                                                  1167 
2312                 ret = strscpy(names, cur->nam    1168                 ret = strscpy(names, cur->name, size);
2313                 if (ret < 0)                     1169                 if (ret < 0)
2314                         return false;            1170                         return false;
2315                                                  1171 
2316                 names += ret;                    1172                 names += ret;
2317                 size -= ret;                     1173                 size -= ret;
2318         }                                        1174         }
2319                                                  1175 
2320         return true;                             1176         return true;
2321 }                                                1177 }
2322                                                  1178 
2323 static bool seccomp_action_logged_from_name(u    1179 static bool seccomp_action_logged_from_name(u32 *action_logged,
2324                                             c    1180                                             const char *name)
2325 {                                                1181 {
2326         const struct seccomp_log_name *cur;      1182         const struct seccomp_log_name *cur;
2327                                                  1183 
2328         for (cur = seccomp_log_names; cur->na    1184         for (cur = seccomp_log_names; cur->name; cur++) {
2329                 if (!strcmp(cur->name, name))    1185                 if (!strcmp(cur->name, name)) {
2330                         *action_logged = cur-    1186                         *action_logged = cur->log;
2331                         return true;             1187                         return true;
2332                 }                                1188                 }
2333         }                                        1189         }
2334                                                  1190 
2335         return false;                            1191         return false;
2336 }                                                1192 }
2337                                                  1193 
2338 static bool seccomp_actions_logged_from_names    1194 static bool seccomp_actions_logged_from_names(u32 *actions_logged, char *names)
2339 {                                                1195 {
2340         char *name;                              1196         char *name;
2341                                                  1197 
2342         *actions_logged = 0;                     1198         *actions_logged = 0;
2343         while ((name = strsep(&names, " ")) &    1199         while ((name = strsep(&names, " ")) && *name) {
2344                 u32 action_logged = 0;           1200                 u32 action_logged = 0;
2345                                                  1201 
2346                 if (!seccomp_action_logged_fr    1202                 if (!seccomp_action_logged_from_name(&action_logged, name))
2347                         return false;            1203                         return false;
2348                                                  1204 
2349                 *actions_logged |= action_log    1205                 *actions_logged |= action_logged;
2350         }                                        1206         }
2351                                                  1207 
2352         return true;                             1208         return true;
2353 }                                                1209 }
2354                                                  1210 
2355 static int read_actions_logged(const struct c !! 1211 static int seccomp_actions_logged_handler(struct ctl_table *ro_table, int write,
2356                                size_t *lenp,  !! 1212                                           void __user *buffer, size_t *lenp,
2357 {                                             !! 1213                                           loff_t *ppos)
2358         char names[sizeof(seccomp_actions_ava << 
2359         struct ctl_table table;               << 
2360                                               << 
2361         memset(names, 0, sizeof(names));      << 
2362                                               << 
2363         if (!seccomp_names_from_actions_logge << 
2364                                               << 
2365                 return -EINVAL;               << 
2366                                               << 
2367         table = *ro_table;                    << 
2368         table.data = names;                   << 
2369         table.maxlen = sizeof(names);         << 
2370         return proc_dostring(&table, 0, buffe << 
2371 }                                             << 
2372                                               << 
2373 static int write_actions_logged(const struct  << 
2374                                 size_t *lenp, << 
2375 {                                                1214 {
2376         char names[sizeof(seccomp_actions_ava    1215         char names[sizeof(seccomp_actions_avail)];
2377         struct ctl_table table;                  1216         struct ctl_table table;
2378         int ret;                                 1217         int ret;
2379                                                  1218 
2380         if (!capable(CAP_SYS_ADMIN))          !! 1219         if (write && !capable(CAP_SYS_ADMIN))
2381                 return -EPERM;                   1220                 return -EPERM;
2382                                                  1221 
2383         memset(names, 0, sizeof(names));         1222         memset(names, 0, sizeof(names));
2384                                                  1223 
                                                   >> 1224         if (!write) {
                                                   >> 1225                 if (!seccomp_names_from_actions_logged(names, sizeof(names),
                                                   >> 1226                                                        seccomp_actions_logged))
                                                   >> 1227                         return -EINVAL;
                                                   >> 1228         }
                                                   >> 1229 
2385         table = *ro_table;                       1230         table = *ro_table;
2386         table.data = names;                      1231         table.data = names;
2387         table.maxlen = sizeof(names);            1232         table.maxlen = sizeof(names);
2388         ret = proc_dostring(&table, 1, buffer !! 1233         ret = proc_dostring(&table, write, buffer, lenp, ppos);
2389         if (ret)                                 1234         if (ret)
2390                 return ret;                      1235                 return ret;
2391                                                  1236 
2392         if (!seccomp_actions_logged_from_name !! 1237         if (write) {
2393                 return -EINVAL;               !! 1238                 u32 actions_logged;
2394                                               << 
2395         if (*actions_logged & SECCOMP_LOG_ALL << 
2396                 return -EINVAL;               << 
2397                                               << 
2398         seccomp_actions_logged = *actions_log << 
2399         return 0;                             << 
2400 }                                             << 
2401                                               << 
2402 static void audit_actions_logged(u32 actions_ << 
2403                                  int ret)     << 
2404 {                                             << 
2405         char names[sizeof(seccomp_actions_ava << 
2406         char old_names[sizeof(seccomp_actions << 
2407         const char *new = names;              << 
2408         const char *old = old_names;          << 
2409                                                  1239 
2410         if (!audit_enabled)                   !! 1240                 if (!seccomp_actions_logged_from_names(&actions_logged,
2411                 return;                       !! 1241                                                        table.data))
                                                   >> 1242                         return -EINVAL;
2412                                                  1243 
2413         memset(names, 0, sizeof(names));      !! 1244                 if (actions_logged & SECCOMP_LOG_ALLOW)
2414         memset(old_names, 0, sizeof(old_names !! 1245                         return -EINVAL;
2415                                                  1246 
2416         if (ret)                              !! 1247                 seccomp_actions_logged = actions_logged;
2417                 new = "?";                    !! 1248         }
2418         else if (!actions_logged)             << 
2419                 new = "(none)";               << 
2420         else if (!seccomp_names_from_actions_ << 
2421                                               << 
2422                 new = "?";                    << 
2423                                               << 
2424         if (!old_actions_logged)              << 
2425                 old = "(none)";               << 
2426         else if (!seccomp_names_from_actions_ << 
2427                                               << 
2428                                               << 
2429                 old = "?";                    << 
2430                                                  1249 
2431         return audit_seccomp_actions_logged(n !! 1250         return 0;
2432 }                                                1251 }
2433                                                  1252 
2434 static int seccomp_actions_logged_handler(con !! 1253 static struct ctl_path seccomp_sysctl_path[] = {
2435                                           voi !! 1254         { .procname = "kernel", },
2436                                           lof !! 1255         { .procname = "seccomp", },
2437 {                                             !! 1256         { }
2438         int ret;                              !! 1257 };
2439                                               << 
2440         if (write) {                          << 
2441                 u32 actions_logged = 0;       << 
2442                 u32 old_actions_logged = secc << 
2443                                               << 
2444                 ret = write_actions_logged(ro << 
2445                                            &a << 
2446                 audit_actions_logged(actions_ << 
2447         } else                                << 
2448                 ret = read_actions_logged(ro_ << 
2449                                               << 
2450         return ret;                           << 
2451 }                                             << 
2452                                                  1258 
2453 static struct ctl_table seccomp_sysctl_table[    1259 static struct ctl_table seccomp_sysctl_table[] = {
2454         {                                        1260         {
2455                 .procname       = "actions_av    1261                 .procname       = "actions_avail",
2456                 .data           = (void *) &s    1262                 .data           = (void *) &seccomp_actions_avail,
2457                 .maxlen         = sizeof(secc    1263                 .maxlen         = sizeof(seccomp_actions_avail),
2458                 .mode           = 0444,          1264                 .mode           = 0444,
2459                 .proc_handler   = proc_dostri    1265                 .proc_handler   = proc_dostring,
2460         },                                       1266         },
2461         {                                        1267         {
2462                 .procname       = "actions_lo    1268                 .procname       = "actions_logged",
2463                 .mode           = 0644,          1269                 .mode           = 0644,
2464                 .proc_handler   = seccomp_act    1270                 .proc_handler   = seccomp_actions_logged_handler,
2465         },                                       1271         },
                                                   >> 1272         { }
2466 };                                               1273 };
2467                                                  1274 
2468 static int __init seccomp_sysctl_init(void)      1275 static int __init seccomp_sysctl_init(void)
2469 {                                                1276 {
2470         register_sysctl_init("kernel/seccomp" !! 1277         struct ctl_table_header *hdr;
                                                   >> 1278 
                                                   >> 1279         hdr = register_sysctl_paths(seccomp_sysctl_path, seccomp_sysctl_table);
                                                   >> 1280         if (!hdr)
                                                   >> 1281                 pr_warn("seccomp: sysctl registration failed\n");
                                                   >> 1282         else
                                                   >> 1283                 kmemleak_not_leak(hdr);
                                                   >> 1284 
2471         return 0;                                1285         return 0;
2472 }                                                1286 }
2473                                                  1287 
2474 device_initcall(seccomp_sysctl_init)             1288 device_initcall(seccomp_sysctl_init)
2475                                                  1289 
2476 #endif /* CONFIG_SYSCTL */                       1290 #endif /* CONFIG_SYSCTL */
2477                                               << 
2478 #ifdef CONFIG_SECCOMP_CACHE_DEBUG             << 
2479 /* Currently CONFIG_SECCOMP_CACHE_DEBUG impli << 
2480 static void proc_pid_seccomp_cache_arch(struc << 
2481                                         const << 
2482 {                                             << 
2483         int nr;                               << 
2484                                               << 
2485         for (nr = 0; nr < bitmap_size; nr++)  << 
2486                 bool cached = test_bit(nr, bi << 
2487                 char *status = cached ? "ALLO << 
2488                                               << 
2489                 seq_printf(m, "%s %d %s\n", n << 
2490         }                                     << 
2491 }                                             << 
2492                                               << 
2493 int proc_pid_seccomp_cache(struct seq_file *m << 
2494                            struct pid *pid, s << 
2495 {                                             << 
2496         struct seccomp_filter *f;             << 
2497         unsigned long flags;                  << 
2498                                               << 
2499         /*                                    << 
2500          * We don't want some sandboxed proce << 
2501          * filters consist of.                << 
2502          */                                   << 
2503         if (!file_ns_capable(m->file, &init_u << 
2504                 return -EACCES;               << 
2505                                               << 
2506         if (!lock_task_sighand(task, &flags)) << 
2507                 return -ESRCH;                << 
2508                                               << 
2509         f = READ_ONCE(task->seccomp.filter);  << 
2510         if (!f) {                             << 
2511                 unlock_task_sighand(task, &fl << 
2512                 return 0;                     << 
2513         }                                     << 
2514                                               << 
2515         /* prevent filter from being freed wh << 
2516         __get_seccomp_filter(f);              << 
2517         unlock_task_sighand(task, &flags);    << 
2518                                               << 
2519         proc_pid_seccomp_cache_arch(m, SECCOM << 
2520                                     f->cache. << 
2521                                     SECCOMP_A << 
2522                                               << 
2523 #ifdef SECCOMP_ARCH_COMPAT                    << 
2524         proc_pid_seccomp_cache_arch(m, SECCOM << 
2525                                     f->cache. << 
2526                                     SECCOMP_A << 
2527 #endif /* SECCOMP_ARCH_COMPAT */              << 
2528                                               << 
2529         __put_seccomp_filter(f);              << 
2530         return 0;                             << 
2531 }                                             << 
2532 #endif /* CONFIG_SECCOMP_CACHE_DEBUG */       << 
2533                                                  1291 

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