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(¤t->sighand-> 224 assert_spin_locked(¤t->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(¤t->sign 279 BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex));
495 assert_spin_locked(¤t->sighand-> 280 assert_spin_locked(¤t->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(¤t->sign 320 BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex));
602 assert_spin_locked(¤t->sighand-> 321 assert_spin_locked(¤t->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(¤t->sighand-> 450 assert_spin_locked(¤t->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(¤t->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 * Emit an audit message when the action is RET_KILL_*, RET_LOG, or the
1009 * FILTER_FLAG_LOG bit was set. The a 597 * FILTER_FLAG_LOG bit was set. The admin has the ability to silence
1010 * any action from being logged by re 598 * any action from being logged by removing the action name from the
1011 * seccomp_actions_logged sysctl. 599 * seccomp_actions_logged sysctl.
1012 */ 600 */
1013 if (!log) 601 if (!log)
1014 return; 602 return;
1015 603
1016 audit_seccomp(syscall, signr, action) 604 audit_seccomp(syscall, signr, action);
1017 } 605 }
1018 606
1019 /* 607 /*
1020 * Secure computing mode 1 allows only read/w 608 * Secure computing mode 1 allows only read/write/exit/sigreturn.
1021 * To be fully secure this must be combined w 609 * To be fully secure this must be combined with rlimit
1022 * to limit the stack allocations too. 610 * to limit the stack allocations too.
1023 */ 611 */
1024 static const int mode1_syscalls[] = { 612 static const int mode1_syscalls[] = {
1025 __NR_seccomp_read, __NR_seccomp_write 613 __NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn,
1026 -1, /* negative terminated */ !! 614 0, /* null terminated */
1027 }; 615 };
1028 616
1029 static void __secure_computing_strict(int thi 617 static void __secure_computing_strict(int this_syscall)
1030 { 618 {
1031 const int *allowed_syscalls = mode1_s !! 619 const int *syscall_whitelist = mode1_syscalls;
1032 #ifdef CONFIG_COMPAT 620 #ifdef CONFIG_COMPAT
1033 if (in_compat_syscall()) 621 if (in_compat_syscall())
1034 allowed_syscalls = get_compat !! 622 syscall_whitelist = get_compat_mode1_syscalls();
1035 #endif 623 #endif
1036 do { 624 do {
1037 if (*allowed_syscalls == this !! 625 if (*syscall_whitelist == this_syscall)
1038 return; 626 return;
1039 } while (*++allowed_syscalls != -1); !! 627 } while (*++syscall_whitelist);
1040 628
1041 #ifdef SECCOMP_DEBUG 629 #ifdef SECCOMP_DEBUG
1042 dump_stack(); 630 dump_stack();
1043 #endif 631 #endif
1044 current->seccomp.mode = SECCOMP_MODE_ <<
1045 seccomp_log(this_syscall, SIGKILL, SE 632 seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true);
1046 do_exit(SIGKILL); 633 do_exit(SIGKILL);
1047 } 634 }
1048 635
1049 #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER 636 #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER
1050 void secure_computing_strict(int this_syscall 637 void secure_computing_strict(int this_syscall)
1051 { 638 {
1052 int mode = current->seccomp.mode; 639 int mode = current->seccomp.mode;
1053 640
1054 if (IS_ENABLED(CONFIG_CHECKPOINT_REST 641 if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
1055 unlikely(current->ptrace & PT_SUS 642 unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
1056 return; 643 return;
1057 644
1058 if (mode == SECCOMP_MODE_DISABLED) 645 if (mode == SECCOMP_MODE_DISABLED)
1059 return; 646 return;
1060 else if (mode == SECCOMP_MODE_STRICT) 647 else if (mode == SECCOMP_MODE_STRICT)
1061 __secure_computing_strict(thi 648 __secure_computing_strict(this_syscall);
1062 else 649 else
1063 BUG(); 650 BUG();
1064 } 651 }
1065 #else 652 #else
1066 653
1067 #ifdef CONFIG_SECCOMP_FILTER 654 #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, 655 static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
1217 const bool rechec 656 const bool recheck_after_trace)
1218 { 657 {
1219 u32 filter_ret, action; 658 u32 filter_ret, action;
1220 struct seccomp_filter *match = NULL; 659 struct seccomp_filter *match = NULL;
1221 int data; 660 int data;
1222 struct seccomp_data sd_local; <<
1223 661
1224 /* 662 /*
1225 * Make sure that any changes to mode 663 * Make sure that any changes to mode from another thread have
1226 * been seen after SYSCALL_WORK_SECCO !! 664 * been seen after TIF_SECCOMP was seen.
1227 */ 665 */
1228 smp_rmb(); !! 666 rmb();
1229 <<
1230 if (!sd) { <<
1231 populate_seccomp_data(&sd_loc <<
1232 sd = &sd_local; <<
1233 } <<
1234 667
1235 filter_ret = seccomp_run_filters(sd, 668 filter_ret = seccomp_run_filters(sd, &match);
1236 data = filter_ret & SECCOMP_RET_DATA; 669 data = filter_ret & SECCOMP_RET_DATA;
1237 action = filter_ret & SECCOMP_RET_ACT 670 action = filter_ret & SECCOMP_RET_ACTION_FULL;
1238 671
1239 switch (action) { 672 switch (action) {
1240 case SECCOMP_RET_ERRNO: 673 case SECCOMP_RET_ERRNO:
1241 /* Set low-order bits as an e 674 /* Set low-order bits as an errno, capped at MAX_ERRNO. */
1242 if (data > MAX_ERRNO) 675 if (data > MAX_ERRNO)
1243 data = MAX_ERRNO; 676 data = MAX_ERRNO;
1244 syscall_set_return_value(curr !! 677 syscall_set_return_value(current, task_pt_regs(current),
1245 -dat 678 -data, 0);
1246 goto skip; 679 goto skip;
1247 680
1248 case SECCOMP_RET_TRAP: 681 case SECCOMP_RET_TRAP:
1249 /* Show the handler the origi 682 /* Show the handler the original registers. */
1250 syscall_rollback(current, cur !! 683 syscall_rollback(current, task_pt_regs(current));
1251 /* Let the filter pass back 1 684 /* Let the filter pass back 16 bits of data. */
1252 force_sig_seccomp(this_syscal !! 685 seccomp_send_sigsys(this_syscall, data);
1253 goto skip; 686 goto skip;
1254 687
1255 case SECCOMP_RET_TRACE: 688 case SECCOMP_RET_TRACE:
1256 /* We've been put in this sta 689 /* We've been put in this state by the ptracer already. */
1257 if (recheck_after_trace) 690 if (recheck_after_trace)
1258 return 0; 691 return 0;
1259 692
1260 /* ENOSYS these calls if ther 693 /* ENOSYS these calls if there is no tracer attached. */
1261 if (!ptrace_event_enabled(cur 694 if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) {
1262 syscall_set_return_va 695 syscall_set_return_value(current,
1263 !! 696 task_pt_regs(current),
1264 697 -ENOSYS, 0);
1265 goto skip; 698 goto skip;
1266 } 699 }
1267 700
1268 /* Allow the BPF to provide t 701 /* Allow the BPF to provide the event message */
1269 ptrace_event(PTRACE_EVENT_SEC 702 ptrace_event(PTRACE_EVENT_SECCOMP, data);
1270 /* 703 /*
1271 * The delivery of a fatal si 704 * The delivery of a fatal signal during event
1272 * notification may silently 705 * notification may silently skip tracer notification,
1273 * which could leave us with 706 * which could leave us with a potentially unmodified
1274 * syscall that the tracer wo 707 * syscall that the tracer would have liked to have
1275 * changed. Since the process 708 * changed. Since the process is about to die, we just
1276 * force the syscall to be sk 709 * force the syscall to be skipped and let the signal
1277 * kill the process and corre 710 * kill the process and correctly handle any tracer exit
1278 * notifications. 711 * notifications.
1279 */ 712 */
1280 if (fatal_signal_pending(curr 713 if (fatal_signal_pending(current))
1281 goto skip; 714 goto skip;
1282 /* Check if the tracer forced 715 /* Check if the tracer forced the syscall to be skipped. */
1283 this_syscall = syscall_get_nr !! 716 this_syscall = syscall_get_nr(current, task_pt_regs(current));
1284 if (this_syscall < 0) 717 if (this_syscall < 0)
1285 goto skip; 718 goto skip;
1286 719
1287 /* 720 /*
1288 * Recheck the syscall, since 721 * Recheck the syscall, since it may have changed. This
1289 * intentionally uses a NULL 722 * intentionally uses a NULL struct seccomp_data to force
1290 * a reload of all registers. 723 * a reload of all registers. This does not goto skip since
1291 * a skip would have already 724 * a skip would have already been reported.
1292 */ 725 */
1293 if (__seccomp_filter(this_sys 726 if (__seccomp_filter(this_syscall, NULL, true))
1294 return -1; 727 return -1;
1295 728
1296 return 0; 729 return 0;
1297 730
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: 731 case SECCOMP_RET_LOG:
1305 seccomp_log(this_syscall, 0, 732 seccomp_log(this_syscall, 0, action, true);
1306 return 0; 733 return 0;
1307 734
1308 case SECCOMP_RET_ALLOW: 735 case SECCOMP_RET_ALLOW:
1309 /* 736 /*
1310 * Note that the "match" filt 737 * Note that the "match" filter will always be NULL for
1311 * this action since SECCOMP_ 738 * this action since SECCOMP_RET_ALLOW is the starting
1312 * state in seccomp_run_filte 739 * state in seccomp_run_filters().
1313 */ 740 */
1314 return 0; 741 return 0;
1315 742
1316 case SECCOMP_RET_KILL_THREAD: 743 case SECCOMP_RET_KILL_THREAD:
1317 case SECCOMP_RET_KILL_PROCESS: 744 case SECCOMP_RET_KILL_PROCESS:
1318 default: 745 default:
1319 current->seccomp.mode = SECCO <<
1320 seccomp_log(this_syscall, SIG 746 seccomp_log(this_syscall, SIGSYS, action, true);
1321 /* Dump core only if this is 747 /* Dump core only if this is the last remaining thread. */
1322 if (action != SECCOMP_RET_KIL !! 748 if (action == SECCOMP_RET_KILL_PROCESS ||
1323 (atomic_read(¤t->si !! 749 get_nr_threads(current) == 1) {
>> 750 siginfo_t info;
>> 751
1324 /* Show the original 752 /* Show the original registers in the dump. */
1325 syscall_rollback(curr !! 753 syscall_rollback(current, task_pt_regs(current));
1326 /* Trigger a coredump !! 754 /* Trigger a manual coredump since do_exit skips it. */
1327 force_sig_seccomp(thi !! 755 seccomp_init_siginfo(&info, this_syscall, data);
1328 } else { !! 756 do_coredump(&info);
1329 do_exit(SIGSYS); <<
1330 } 757 }
1331 return -1; /* skip the syscal !! 758 if (action == SECCOMP_RET_KILL_PROCESS)
>> 759 do_group_exit(SIGSYS);
>> 760 else
>> 761 do_exit(SIGSYS);
1332 } 762 }
1333 763
1334 unreachable(); 764 unreachable();
1335 765
1336 skip: 766 skip:
1337 seccomp_log(this_syscall, 0, action, 767 seccomp_log(this_syscall, 0, action, match ? match->log : false);
1338 return -1; 768 return -1;
1339 } 769 }
1340 #else 770 #else
1341 static int __seccomp_filter(int this_syscall, 771 static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
1342 const bool rechec 772 const bool recheck_after_trace)
1343 { 773 {
1344 BUG(); 774 BUG();
1345 <<
1346 return -1; <<
1347 } 775 }
1348 #endif 776 #endif
1349 777
1350 int __secure_computing(const struct seccomp_d 778 int __secure_computing(const struct seccomp_data *sd)
1351 { 779 {
1352 int mode = current->seccomp.mode; 780 int mode = current->seccomp.mode;
1353 int this_syscall; 781 int this_syscall;
1354 782
1355 if (IS_ENABLED(CONFIG_CHECKPOINT_REST 783 if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
1356 unlikely(current->ptrace & PT_SUS 784 unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
1357 return 0; 785 return 0;
1358 786
1359 this_syscall = sd ? sd->nr : 787 this_syscall = sd ? sd->nr :
1360 syscall_get_nr(current, curre !! 788 syscall_get_nr(current, task_pt_regs(current));
1361 789
1362 switch (mode) { 790 switch (mode) {
1363 case SECCOMP_MODE_STRICT: 791 case SECCOMP_MODE_STRICT:
1364 __secure_computing_strict(thi 792 __secure_computing_strict(this_syscall); /* may call do_exit */
1365 return 0; 793 return 0;
1366 case SECCOMP_MODE_FILTER: 794 case SECCOMP_MODE_FILTER:
1367 return __seccomp_filter(this_ 795 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: 796 default:
1374 BUG(); 797 BUG();
1375 } 798 }
1376 } 799 }
1377 #endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */ 800 #endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */
1378 801
1379 long prctl_get_seccomp(void) 802 long prctl_get_seccomp(void)
1380 { 803 {
1381 return current->seccomp.mode; 804 return current->seccomp.mode;
1382 } 805 }
1383 806
1384 /** 807 /**
1385 * seccomp_set_mode_strict: internal function 808 * seccomp_set_mode_strict: internal function for setting strict seccomp
1386 * 809 *
1387 * Once current->seccomp.mode is non-zero, it 810 * Once current->seccomp.mode is non-zero, it may not be changed.
1388 * 811 *
1389 * Returns 0 on success or -EINVAL on failure 812 * Returns 0 on success or -EINVAL on failure.
1390 */ 813 */
1391 static long seccomp_set_mode_strict(void) 814 static long seccomp_set_mode_strict(void)
1392 { 815 {
1393 const unsigned long seccomp_mode = SE 816 const unsigned long seccomp_mode = SECCOMP_MODE_STRICT;
1394 long ret = -EINVAL; 817 long ret = -EINVAL;
1395 818
1396 spin_lock_irq(¤t->sighand->sigl 819 spin_lock_irq(¤t->sighand->siglock);
1397 820
1398 if (!seccomp_may_assign_mode(seccomp_ 821 if (!seccomp_may_assign_mode(seccomp_mode))
1399 goto out; 822 goto out;
1400 823
1401 #ifdef TIF_NOTSC 824 #ifdef TIF_NOTSC
1402 disable_TSC(); 825 disable_TSC();
1403 #endif 826 #endif
1404 seccomp_assign_mode(current, seccomp_ 827 seccomp_assign_mode(current, seccomp_mode, 0);
1405 ret = 0; 828 ret = 0;
1406 829
1407 out: 830 out:
1408 spin_unlock_irq(¤t->sighand->si 831 spin_unlock_irq(¤t->sighand->siglock);
1409 832
1410 return ret; 833 return ret;
1411 } 834 }
1412 835
1413 #ifdef CONFIG_SECCOMP_FILTER 836 #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(¤t->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 /** 837 /**
1907 * seccomp_set_mode_filter: internal function 838 * seccomp_set_mode_filter: internal function for setting seccomp filter
1908 * @flags: flags to change filter behavior 839 * @flags: flags to change filter behavior
1909 * @filter: struct sock_fprog containing filt 840 * @filter: struct sock_fprog containing filter
1910 * 841 *
1911 * This function may be called repeatedly to 842 * This function may be called repeatedly to install additional filters.
1912 * Every filter successfully installed will b 843 * Every filter successfully installed will be evaluated (in reverse order)
1913 * for each system call the task makes. 844 * for each system call the task makes.
1914 * 845 *
1915 * Once current->seccomp.mode is non-zero, it 846 * Once current->seccomp.mode is non-zero, it may not be changed.
1916 * 847 *
1917 * Returns 0 on success or -EINVAL on failure 848 * Returns 0 on success or -EINVAL on failure.
1918 */ 849 */
1919 static long seccomp_set_mode_filter(unsigned 850 static long seccomp_set_mode_filter(unsigned int flags,
1920 const cha 851 const char __user *filter)
1921 { 852 {
1922 const unsigned long seccomp_mode = SE 853 const unsigned long seccomp_mode = SECCOMP_MODE_FILTER;
1923 struct seccomp_filter *prepared = NUL 854 struct seccomp_filter *prepared = NULL;
1924 long ret = -EINVAL; 855 long ret = -EINVAL;
1925 int listener = -1; <<
1926 struct file *listener_f = NULL; <<
1927 856
1928 /* Validate flags. */ 857 /* Validate flags. */
1929 if (flags & ~SECCOMP_FILTER_FLAG_MASK 858 if (flags & ~SECCOMP_FILTER_FLAG_MASK)
1930 return -EINVAL; 859 return -EINVAL;
1931 860
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 861 /* Prepare the new filter before holding any locks. */
1953 prepared = seccomp_prepare_user_filte 862 prepared = seccomp_prepare_user_filter(filter);
1954 if (IS_ERR(prepared)) 863 if (IS_ERR(prepared))
1955 return PTR_ERR(prepared); 864 return PTR_ERR(prepared);
1956 865
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 /* 866 /*
1973 * Make sure we cannot change seccomp 867 * Make sure we cannot change seccomp or nnp state via TSYNC
1974 * while another thread is in the mid 868 * while another thread is in the middle of calling exec.
1975 */ 869 */
1976 if (flags & SECCOMP_FILTER_FLAG_TSYNC 870 if (flags & SECCOMP_FILTER_FLAG_TSYNC &&
1977 mutex_lock_killable(¤t->sig 871 mutex_lock_killable(¤t->signal->cred_guard_mutex))
1978 goto out_put_fd; !! 872 goto out_free;
1979 873
1980 spin_lock_irq(¤t->sighand->sigl 874 spin_lock_irq(¤t->sighand->siglock);
1981 875
1982 if (!seccomp_may_assign_mode(seccomp_ 876 if (!seccomp_may_assign_mode(seccomp_mode))
1983 goto out; 877 goto out;
1984 878
1985 if (has_duplicate_listener(prepared)) <<
1986 ret = -EBUSY; <<
1987 goto out; <<
1988 } <<
1989 <<
1990 ret = seccomp_attach_filter(flags, pr 879 ret = seccomp_attach_filter(flags, prepared);
1991 if (ret) 880 if (ret)
1992 goto out; 881 goto out;
1993 /* Do not free the successfully attac 882 /* Do not free the successfully attached filter. */
1994 prepared = NULL; 883 prepared = NULL;
1995 884
1996 seccomp_assign_mode(current, seccomp_ 885 seccomp_assign_mode(current, seccomp_mode, flags);
1997 out: 886 out:
1998 spin_unlock_irq(¤t->sighand->si 887 spin_unlock_irq(¤t->sighand->siglock);
1999 if (flags & SECCOMP_FILTER_FLAG_TSYNC 888 if (flags & SECCOMP_FILTER_FLAG_TSYNC)
2000 mutex_unlock(¤t->signal 889 mutex_unlock(¤t->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: 890 out_free:
2014 seccomp_filter_free(prepared); 891 seccomp_filter_free(prepared);
2015 return ret; 892 return ret;
2016 } 893 }
2017 #else 894 #else
2018 static inline long seccomp_set_mode_filter(un 895 static inline long seccomp_set_mode_filter(unsigned int flags,
2019 co 896 const char __user *filter)
2020 { 897 {
2021 return -EINVAL; 898 return -EINVAL;
2022 } 899 }
2023 #endif 900 #endif
2024 901
2025 static long seccomp_get_action_avail(const ch 902 static long seccomp_get_action_avail(const char __user *uaction)
2026 { 903 {
2027 u32 action; 904 u32 action;
2028 905
2029 if (copy_from_user(&action, uaction, 906 if (copy_from_user(&action, uaction, sizeof(action)))
2030 return -EFAULT; 907 return -EFAULT;
2031 908
2032 switch (action) { 909 switch (action) {
2033 case SECCOMP_RET_KILL_PROCESS: 910 case SECCOMP_RET_KILL_PROCESS:
2034 case SECCOMP_RET_KILL_THREAD: 911 case SECCOMP_RET_KILL_THREAD:
2035 case SECCOMP_RET_TRAP: 912 case SECCOMP_RET_TRAP:
2036 case SECCOMP_RET_ERRNO: 913 case SECCOMP_RET_ERRNO:
2037 case SECCOMP_RET_USER_NOTIF: <<
2038 case SECCOMP_RET_TRACE: 914 case SECCOMP_RET_TRACE:
2039 case SECCOMP_RET_LOG: 915 case SECCOMP_RET_LOG:
2040 case SECCOMP_RET_ALLOW: 916 case SECCOMP_RET_ALLOW:
2041 break; 917 break;
2042 default: 918 default:
2043 return -EOPNOTSUPP; 919 return -EOPNOTSUPP;
2044 } 920 }
2045 921
2046 return 0; 922 return 0;
2047 } 923 }
2048 924
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 925 /* Common entry point for both prctl and syscall. */
2064 static long do_seccomp(unsigned int op, unsig 926 static long do_seccomp(unsigned int op, unsigned int flags,
2065 void __user *uargs) !! 927 const char __user *uargs)
2066 { 928 {
2067 switch (op) { 929 switch (op) {
2068 case SECCOMP_SET_MODE_STRICT: 930 case SECCOMP_SET_MODE_STRICT:
2069 if (flags != 0 || uargs != NU 931 if (flags != 0 || uargs != NULL)
2070 return -EINVAL; 932 return -EINVAL;
2071 return seccomp_set_mode_stric 933 return seccomp_set_mode_strict();
2072 case SECCOMP_SET_MODE_FILTER: 934 case SECCOMP_SET_MODE_FILTER:
2073 return seccomp_set_mode_filte 935 return seccomp_set_mode_filter(flags, uargs);
2074 case SECCOMP_GET_ACTION_AVAIL: 936 case SECCOMP_GET_ACTION_AVAIL:
2075 if (flags != 0) 937 if (flags != 0)
2076 return -EINVAL; 938 return -EINVAL;
2077 939
2078 return seccomp_get_action_ava 940 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: 941 default:
2085 return -EINVAL; 942 return -EINVAL;
2086 } 943 }
2087 } 944 }
2088 945
2089 SYSCALL_DEFINE3(seccomp, unsigned int, op, un 946 SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags,
2090 void __user *, uargs !! 947 const char __user *, uargs)
2091 { 948 {
2092 return do_seccomp(op, flags, uargs); 949 return do_seccomp(op, flags, uargs);
2093 } 950 }
2094 951
2095 /** 952 /**
2096 * prctl_set_seccomp: configures current->sec 953 * prctl_set_seccomp: configures current->seccomp.mode
2097 * @seccomp_mode: requested mode to use 954 * @seccomp_mode: requested mode to use
2098 * @filter: optional struct sock_fprog for us 955 * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER
2099 * 956 *
2100 * Returns 0 on success or -EINVAL on failure 957 * Returns 0 on success or -EINVAL on failure.
2101 */ 958 */
2102 long prctl_set_seccomp(unsigned long seccomp_ !! 959 long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter)
2103 { 960 {
2104 unsigned int op; 961 unsigned int op;
2105 void __user *uargs; !! 962 char __user *uargs;
2106 963
2107 switch (seccomp_mode) { 964 switch (seccomp_mode) {
2108 case SECCOMP_MODE_STRICT: 965 case SECCOMP_MODE_STRICT:
2109 op = SECCOMP_SET_MODE_STRICT; 966 op = SECCOMP_SET_MODE_STRICT;
2110 /* 967 /*
2111 * Setting strict mode throug 968 * Setting strict mode through prctl always ignored filter,
2112 * so make sure it is always 969 * so make sure it is always NULL here to pass the internal
2113 * check in do_seccomp(). 970 * check in do_seccomp().
2114 */ 971 */
2115 uargs = NULL; 972 uargs = NULL;
2116 break; 973 break;
2117 case SECCOMP_MODE_FILTER: 974 case SECCOMP_MODE_FILTER:
2118 op = SECCOMP_SET_MODE_FILTER; 975 op = SECCOMP_SET_MODE_FILTER;
2119 uargs = filter; 976 uargs = filter;
2120 break; 977 break;
2121 default: 978 default:
2122 return -EINVAL; 979 return -EINVAL;
2123 } 980 }
2124 981
2125 /* prctl interface doesn't have flags 982 /* prctl interface doesn't have flags, so they are always zero. */
2126 return do_seccomp(op, 0, uargs); 983 return do_seccomp(op, 0, uargs);
2127 } 984 }
2128 985
2129 #if defined(CONFIG_SECCOMP_FILTER) && defined 986 #if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE)
2130 static struct seccomp_filter *get_nth_filter( 987 static struct seccomp_filter *get_nth_filter(struct task_struct *task,
2131 988 unsigned long filter_off)
2132 { 989 {
2133 struct seccomp_filter *orig, *filter; 990 struct seccomp_filter *orig, *filter;
2134 unsigned long count; 991 unsigned long count;
2135 992
2136 /* 993 /*
2137 * Note: this is only correct because 994 * Note: this is only correct because the caller should be the (ptrace)
2138 * tracer of the task, otherwise lock 995 * tracer of the task, otherwise lock_task_sighand is needed.
2139 */ 996 */
2140 spin_lock_irq(&task->sighand->siglock 997 spin_lock_irq(&task->sighand->siglock);
2141 998
2142 if (task->seccomp.mode != SECCOMP_MOD 999 if (task->seccomp.mode != SECCOMP_MODE_FILTER) {
2143 spin_unlock_irq(&task->sighan 1000 spin_unlock_irq(&task->sighand->siglock);
2144 return ERR_PTR(-EINVAL); 1001 return ERR_PTR(-EINVAL);
2145 } 1002 }
2146 1003
2147 orig = task->seccomp.filter; 1004 orig = task->seccomp.filter;
2148 __get_seccomp_filter(orig); 1005 __get_seccomp_filter(orig);
2149 spin_unlock_irq(&task->sighand->siglo 1006 spin_unlock_irq(&task->sighand->siglock);
2150 1007
2151 count = 0; 1008 count = 0;
2152 for (filter = orig; filter; filter = 1009 for (filter = orig; filter; filter = filter->prev)
2153 count++; 1010 count++;
2154 1011
2155 if (filter_off >= count) { 1012 if (filter_off >= count) {
2156 filter = ERR_PTR(-ENOENT); 1013 filter = ERR_PTR(-ENOENT);
2157 goto out; 1014 goto out;
2158 } 1015 }
2159 1016
2160 count -= filter_off; 1017 count -= filter_off;
2161 for (filter = orig; filter && count > 1018 for (filter = orig; filter && count > 1; filter = filter->prev)
2162 count--; 1019 count--;
2163 1020
2164 if (WARN_ON(count != 1 || !filter)) { 1021 if (WARN_ON(count != 1 || !filter)) {
2165 filter = ERR_PTR(-ENOENT); 1022 filter = ERR_PTR(-ENOENT);
2166 goto out; 1023 goto out;
2167 } 1024 }
2168 1025
2169 __get_seccomp_filter(filter); 1026 __get_seccomp_filter(filter);
2170 1027
2171 out: 1028 out:
2172 __put_seccomp_filter(orig); 1029 __put_seccomp_filter(orig);
2173 return filter; 1030 return filter;
2174 } 1031 }
2175 1032
2176 long seccomp_get_filter(struct task_struct *t 1033 long seccomp_get_filter(struct task_struct *task, unsigned long filter_off,
2177 void __user *data) 1034 void __user *data)
2178 { 1035 {
2179 struct seccomp_filter *filter; 1036 struct seccomp_filter *filter;
2180 struct sock_fprog_kern *fprog; 1037 struct sock_fprog_kern *fprog;
2181 long ret; 1038 long ret;
2182 1039
2183 if (!capable(CAP_SYS_ADMIN) || 1040 if (!capable(CAP_SYS_ADMIN) ||
2184 current->seccomp.mode != SECCOMP_ 1041 current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2185 return -EACCES; 1042 return -EACCES;
2186 } 1043 }
2187 1044
2188 filter = get_nth_filter(task, filter_ 1045 filter = get_nth_filter(task, filter_off);
2189 if (IS_ERR(filter)) 1046 if (IS_ERR(filter))
2190 return PTR_ERR(filter); 1047 return PTR_ERR(filter);
2191 1048
2192 fprog = filter->prog->orig_prog; 1049 fprog = filter->prog->orig_prog;
2193 if (!fprog) { 1050 if (!fprog) {
2194 /* This must be a new non-cBP 1051 /* This must be a new non-cBPF filter, since we save
2195 * every cBPF filter's orig_p 1052 * every cBPF filter's orig_prog above when
2196 * CONFIG_CHECKPOINT_RESTORE 1053 * CONFIG_CHECKPOINT_RESTORE is enabled.
2197 */ 1054 */
2198 ret = -EMEDIUMTYPE; 1055 ret = -EMEDIUMTYPE;
2199 goto out; 1056 goto out;
2200 } 1057 }
2201 1058
2202 ret = fprog->len; 1059 ret = fprog->len;
2203 if (!data) 1060 if (!data)
2204 goto out; 1061 goto out;
2205 1062
2206 if (copy_to_user(data, fprog->filter, 1063 if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog)))
2207 ret = -EFAULT; 1064 ret = -EFAULT;
2208 1065
2209 out: 1066 out:
2210 __put_seccomp_filter(filter); 1067 __put_seccomp_filter(filter);
2211 return ret; 1068 return ret;
2212 } 1069 }
2213 1070
2214 long seccomp_get_metadata(struct task_struct 1071 long seccomp_get_metadata(struct task_struct *task,
2215 unsigned long size, 1072 unsigned long size, void __user *data)
2216 { 1073 {
2217 long ret; 1074 long ret;
2218 struct seccomp_filter *filter; 1075 struct seccomp_filter *filter;
2219 struct seccomp_metadata kmd = {}; 1076 struct seccomp_metadata kmd = {};
2220 1077
2221 if (!capable(CAP_SYS_ADMIN) || 1078 if (!capable(CAP_SYS_ADMIN) ||
2222 current->seccomp.mode != SECCOMP_ 1079 current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2223 return -EACCES; 1080 return -EACCES;
2224 } 1081 }
2225 1082
2226 size = min_t(unsigned long, size, siz 1083 size = min_t(unsigned long, size, sizeof(kmd));
2227 1084
2228 if (size < sizeof(kmd.filter_off)) 1085 if (size < sizeof(kmd.filter_off))
2229 return -EINVAL; 1086 return -EINVAL;
2230 1087
2231 if (copy_from_user(&kmd.filter_off, d 1088 if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off)))
2232 return -EFAULT; 1089 return -EFAULT;
2233 1090
2234 filter = get_nth_filter(task, kmd.fil 1091 filter = get_nth_filter(task, kmd.filter_off);
2235 if (IS_ERR(filter)) 1092 if (IS_ERR(filter))
2236 return PTR_ERR(filter); 1093 return PTR_ERR(filter);
2237 1094
2238 if (filter->log) 1095 if (filter->log)
2239 kmd.flags |= SECCOMP_FILTER_F 1096 kmd.flags |= SECCOMP_FILTER_FLAG_LOG;
2240 1097
2241 ret = size; 1098 ret = size;
2242 if (copy_to_user(data, &kmd, size)) 1099 if (copy_to_user(data, &kmd, size))
2243 ret = -EFAULT; 1100 ret = -EFAULT;
2244 1101
2245 __put_seccomp_filter(filter); 1102 __put_seccomp_filter(filter);
2246 return ret; 1103 return ret;
2247 } 1104 }
2248 #endif 1105 #endif
2249 1106
2250 #ifdef CONFIG_SYSCTL 1107 #ifdef CONFIG_SYSCTL
2251 1108
2252 /* Human readable action names for friendly s 1109 /* Human readable action names for friendly sysctl interaction */
2253 #define SECCOMP_RET_KILL_PROCESS_NAME "kill 1110 #define SECCOMP_RET_KILL_PROCESS_NAME "kill_process"
2254 #define SECCOMP_RET_KILL_THREAD_NAME "kill 1111 #define SECCOMP_RET_KILL_THREAD_NAME "kill_thread"
2255 #define SECCOMP_RET_TRAP_NAME "trap 1112 #define SECCOMP_RET_TRAP_NAME "trap"
2256 #define SECCOMP_RET_ERRNO_NAME "errn 1113 #define SECCOMP_RET_ERRNO_NAME "errno"
2257 #define SECCOMP_RET_USER_NOTIF_NAME "user <<
2258 #define SECCOMP_RET_TRACE_NAME "trac 1114 #define SECCOMP_RET_TRACE_NAME "trace"
2259 #define SECCOMP_RET_LOG_NAME "log" 1115 #define SECCOMP_RET_LOG_NAME "log"
2260 #define SECCOMP_RET_ALLOW_NAME "allo 1116 #define SECCOMP_RET_ALLOW_NAME "allow"
2261 1117
2262 static const char seccomp_actions_avail[] = 1118 static const char seccomp_actions_avail[] =
2263 SECCOMP_RET_K 1119 SECCOMP_RET_KILL_PROCESS_NAME " "
2264 SECCOMP_RET_K 1120 SECCOMP_RET_KILL_THREAD_NAME " "
2265 SECCOMP_RET_T 1121 SECCOMP_RET_TRAP_NAME " "
2266 SECCOMP_RET_E 1122 SECCOMP_RET_ERRNO_NAME " "
2267 SECCOMP_RET_U <<
2268 SECCOMP_RET_T 1123 SECCOMP_RET_TRACE_NAME " "
2269 SECCOMP_RET_L 1124 SECCOMP_RET_LOG_NAME " "
2270 SECCOMP_RET_A 1125 SECCOMP_RET_ALLOW_NAME;
2271 1126
2272 struct seccomp_log_name { 1127 struct seccomp_log_name {
2273 u32 log; 1128 u32 log;
2274 const char *name; 1129 const char *name;
2275 }; 1130 };
2276 1131
2277 static const struct seccomp_log_name seccomp_ 1132 static const struct seccomp_log_name seccomp_log_names[] = {
2278 { SECCOMP_LOG_KILL_PROCESS, SECCOMP_R 1133 { SECCOMP_LOG_KILL_PROCESS, SECCOMP_RET_KILL_PROCESS_NAME },
2279 { SECCOMP_LOG_KILL_THREAD, SECCOMP_RE 1134 { SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME },
2280 { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_ 1135 { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME },
2281 { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRN 1136 { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME },
2282 { SECCOMP_LOG_USER_NOTIF, SECCOMP_RET <<
2283 { SECCOMP_LOG_TRACE, SECCOMP_RET_TRAC 1137 { SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME },
2284 { SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NA 1138 { SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NAME },
2285 { SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLO 1139 { SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLOW_NAME },
2286 { } 1140 { }
2287 }; 1141 };
2288 1142
2289 static bool seccomp_names_from_actions_logged 1143 static bool seccomp_names_from_actions_logged(char *names, size_t size,
2290 1144 u32 actions_logged,
2291 1145 const char *sep)
2292 { 1146 {
2293 const struct seccomp_log_name *cur; 1147 const struct seccomp_log_name *cur;
2294 bool append_sep = false; 1148 bool append_sep = false;
2295 1149
2296 for (cur = seccomp_log_names; cur->na 1150 for (cur = seccomp_log_names; cur->name && size; cur++) {
2297 ssize_t ret; 1151 ssize_t ret;
2298 1152
2299 if (!(actions_logged & cur->l 1153 if (!(actions_logged & cur->log))
2300 continue; 1154 continue;
2301 1155
2302 if (append_sep) { 1156 if (append_sep) {
2303 ret = strscpy(names, 1157 ret = strscpy(names, sep, size);
2304 if (ret < 0) 1158 if (ret < 0)
2305 return false; 1159 return false;
2306 1160
2307 names += ret; 1161 names += ret;
2308 size -= ret; 1162 size -= ret;
2309 } else 1163 } else
2310 append_sep = true; 1164 append_sep = true;
2311 1165
2312 ret = strscpy(names, cur->nam 1166 ret = strscpy(names, cur->name, size);
2313 if (ret < 0) 1167 if (ret < 0)
2314 return false; 1168 return false;
2315 1169
2316 names += ret; 1170 names += ret;
2317 size -= ret; 1171 size -= ret;
2318 } 1172 }
2319 1173
2320 return true; 1174 return true;
2321 } 1175 }
2322 1176
2323 static bool seccomp_action_logged_from_name(u 1177 static bool seccomp_action_logged_from_name(u32 *action_logged,
2324 c 1178 const char *name)
2325 { 1179 {
2326 const struct seccomp_log_name *cur; 1180 const struct seccomp_log_name *cur;
2327 1181
2328 for (cur = seccomp_log_names; cur->na 1182 for (cur = seccomp_log_names; cur->name; cur++) {
2329 if (!strcmp(cur->name, name)) 1183 if (!strcmp(cur->name, name)) {
2330 *action_logged = cur- 1184 *action_logged = cur->log;
2331 return true; 1185 return true;
2332 } 1186 }
2333 } 1187 }
2334 1188
2335 return false; 1189 return false;
2336 } 1190 }
2337 1191
2338 static bool seccomp_actions_logged_from_names 1192 static bool seccomp_actions_logged_from_names(u32 *actions_logged, char *names)
2339 { 1193 {
2340 char *name; 1194 char *name;
2341 1195
2342 *actions_logged = 0; 1196 *actions_logged = 0;
2343 while ((name = strsep(&names, " ")) & 1197 while ((name = strsep(&names, " ")) && *name) {
2344 u32 action_logged = 0; 1198 u32 action_logged = 0;
2345 1199
2346 if (!seccomp_action_logged_fr 1200 if (!seccomp_action_logged_from_name(&action_logged, name))
2347 return false; 1201 return false;
2348 1202
2349 *actions_logged |= action_log 1203 *actions_logged |= action_logged;
2350 } 1204 }
2351 1205
2352 return true; 1206 return true;
2353 } 1207 }
2354 1208
2355 static int read_actions_logged(const struct c !! 1209 static int read_actions_logged(struct ctl_table *ro_table, void __user *buffer,
2356 size_t *lenp, 1210 size_t *lenp, loff_t *ppos)
2357 { 1211 {
2358 char names[sizeof(seccomp_actions_ava 1212 char names[sizeof(seccomp_actions_avail)];
2359 struct ctl_table table; 1213 struct ctl_table table;
2360 1214
2361 memset(names, 0, sizeof(names)); 1215 memset(names, 0, sizeof(names));
2362 1216
2363 if (!seccomp_names_from_actions_logge 1217 if (!seccomp_names_from_actions_logged(names, sizeof(names),
2364 1218 seccomp_actions_logged, " "))
2365 return -EINVAL; 1219 return -EINVAL;
2366 1220
2367 table = *ro_table; 1221 table = *ro_table;
2368 table.data = names; 1222 table.data = names;
2369 table.maxlen = sizeof(names); 1223 table.maxlen = sizeof(names);
2370 return proc_dostring(&table, 0, buffe 1224 return proc_dostring(&table, 0, buffer, lenp, ppos);
2371 } 1225 }
2372 1226
2373 static int write_actions_logged(const struct !! 1227 static int write_actions_logged(struct ctl_table *ro_table, void __user *buffer,
2374 size_t *lenp, 1228 size_t *lenp, loff_t *ppos, u32 *actions_logged)
2375 { 1229 {
2376 char names[sizeof(seccomp_actions_ava 1230 char names[sizeof(seccomp_actions_avail)];
2377 struct ctl_table table; 1231 struct ctl_table table;
2378 int ret; 1232 int ret;
2379 1233
2380 if (!capable(CAP_SYS_ADMIN)) 1234 if (!capable(CAP_SYS_ADMIN))
2381 return -EPERM; 1235 return -EPERM;
2382 1236
2383 memset(names, 0, sizeof(names)); 1237 memset(names, 0, sizeof(names));
2384 1238
2385 table = *ro_table; 1239 table = *ro_table;
2386 table.data = names; 1240 table.data = names;
2387 table.maxlen = sizeof(names); 1241 table.maxlen = sizeof(names);
2388 ret = proc_dostring(&table, 1, buffer 1242 ret = proc_dostring(&table, 1, buffer, lenp, ppos);
2389 if (ret) 1243 if (ret)
2390 return ret; 1244 return ret;
2391 1245
2392 if (!seccomp_actions_logged_from_name 1246 if (!seccomp_actions_logged_from_names(actions_logged, table.data))
2393 return -EINVAL; 1247 return -EINVAL;
2394 1248
2395 if (*actions_logged & SECCOMP_LOG_ALL 1249 if (*actions_logged & SECCOMP_LOG_ALLOW)
2396 return -EINVAL; 1250 return -EINVAL;
2397 1251
2398 seccomp_actions_logged = *actions_log 1252 seccomp_actions_logged = *actions_logged;
2399 return 0; 1253 return 0;
2400 } 1254 }
2401 1255
2402 static void audit_actions_logged(u32 actions_ 1256 static void audit_actions_logged(u32 actions_logged, u32 old_actions_logged,
2403 int ret) 1257 int ret)
2404 { 1258 {
2405 char names[sizeof(seccomp_actions_ava 1259 char names[sizeof(seccomp_actions_avail)];
2406 char old_names[sizeof(seccomp_actions 1260 char old_names[sizeof(seccomp_actions_avail)];
2407 const char *new = names; 1261 const char *new = names;
2408 const char *old = old_names; 1262 const char *old = old_names;
2409 1263
2410 if (!audit_enabled) 1264 if (!audit_enabled)
2411 return; 1265 return;
2412 1266
2413 memset(names, 0, sizeof(names)); 1267 memset(names, 0, sizeof(names));
2414 memset(old_names, 0, sizeof(old_names 1268 memset(old_names, 0, sizeof(old_names));
2415 1269
2416 if (ret) 1270 if (ret)
2417 new = "?"; 1271 new = "?";
2418 else if (!actions_logged) 1272 else if (!actions_logged)
2419 new = "(none)"; 1273 new = "(none)";
2420 else if (!seccomp_names_from_actions_ 1274 else if (!seccomp_names_from_actions_logged(names, sizeof(names),
2421 1275 actions_logged, ","))
2422 new = "?"; 1276 new = "?";
2423 1277
2424 if (!old_actions_logged) 1278 if (!old_actions_logged)
2425 old = "(none)"; 1279 old = "(none)";
2426 else if (!seccomp_names_from_actions_ 1280 else if (!seccomp_names_from_actions_logged(old_names,
2427 1281 sizeof(old_names),
2428 1282 old_actions_logged, ","))
2429 old = "?"; 1283 old = "?";
2430 1284
2431 return audit_seccomp_actions_logged(n 1285 return audit_seccomp_actions_logged(new, old, !ret);
2432 } 1286 }
2433 1287
2434 static int seccomp_actions_logged_handler(con !! 1288 static int seccomp_actions_logged_handler(struct ctl_table *ro_table, int write,
2435 voi !! 1289 void __user *buffer, size_t *lenp,
2436 lof 1290 loff_t *ppos)
2437 { 1291 {
2438 int ret; 1292 int ret;
2439 1293
2440 if (write) { 1294 if (write) {
2441 u32 actions_logged = 0; 1295 u32 actions_logged = 0;
2442 u32 old_actions_logged = secc 1296 u32 old_actions_logged = seccomp_actions_logged;
2443 1297
2444 ret = write_actions_logged(ro 1298 ret = write_actions_logged(ro_table, buffer, lenp, ppos,
2445 &a 1299 &actions_logged);
2446 audit_actions_logged(actions_ 1300 audit_actions_logged(actions_logged, old_actions_logged, ret);
2447 } else 1301 } else
2448 ret = read_actions_logged(ro_ 1302 ret = read_actions_logged(ro_table, buffer, lenp, ppos);
2449 1303
2450 return ret; 1304 return ret;
2451 } 1305 }
2452 1306
>> 1307 static struct ctl_path seccomp_sysctl_path[] = {
>> 1308 { .procname = "kernel", },
>> 1309 { .procname = "seccomp", },
>> 1310 { }
>> 1311 };
>> 1312
2453 static struct ctl_table seccomp_sysctl_table[ 1313 static struct ctl_table seccomp_sysctl_table[] = {
2454 { 1314 {
2455 .procname = "actions_av 1315 .procname = "actions_avail",
2456 .data = (void *) &s 1316 .data = (void *) &seccomp_actions_avail,
2457 .maxlen = sizeof(secc 1317 .maxlen = sizeof(seccomp_actions_avail),
2458 .mode = 0444, 1318 .mode = 0444,
2459 .proc_handler = proc_dostri 1319 .proc_handler = proc_dostring,
2460 }, 1320 },
2461 { 1321 {
2462 .procname = "actions_lo 1322 .procname = "actions_logged",
2463 .mode = 0644, 1323 .mode = 0644,
2464 .proc_handler = seccomp_act 1324 .proc_handler = seccomp_actions_logged_handler,
2465 }, 1325 },
>> 1326 { }
2466 }; 1327 };
2467 1328
2468 static int __init seccomp_sysctl_init(void) 1329 static int __init seccomp_sysctl_init(void)
2469 { 1330 {
2470 register_sysctl_init("kernel/seccomp" !! 1331 struct ctl_table_header *hdr;
>> 1332
>> 1333 hdr = register_sysctl_paths(seccomp_sysctl_path, seccomp_sysctl_table);
>> 1334 if (!hdr)
>> 1335 pr_warn("seccomp: sysctl registration failed\n");
>> 1336 else
>> 1337 kmemleak_not_leak(hdr);
>> 1338
2471 return 0; 1339 return 0;
2472 } 1340 }
2473 1341
2474 device_initcall(seccomp_sysctl_init) 1342 device_initcall(seccomp_sysctl_init)
2475 1343
2476 #endif /* CONFIG_SYSCTL */ 1344 #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 1345
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.