1 /* SPDX-License-Identifier: GPL-2.0-or-later * 1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* 2 /*
3 * Copyright 1997-1998 Transmeta Corporation 3 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
4 * Copyright 2005-2006 Ian Kent <raven@themaw 4 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
5 */ 5 */
6 6
7 /* Internal header file for autofs */ 7 /* Internal header file for autofs */
8 8
9 #include <linux/auto_fs.h> 9 #include <linux/auto_fs.h>
10 #include <linux/auto_dev-ioctl.h> 10 #include <linux/auto_dev-ioctl.h>
11 11
12 #include <linux/kernel.h> 12 #include <linux/kernel.h>
13 #include <linux/slab.h> 13 #include <linux/slab.h>
14 #include <linux/time.h> 14 #include <linux/time.h>
15 #include <linux/string.h> 15 #include <linux/string.h>
16 #include <linux/wait.h> 16 #include <linux/wait.h>
17 #include <linux/sched.h> 17 #include <linux/sched.h>
18 #include <linux/sched/signal.h> 18 #include <linux/sched/signal.h>
19 #include <linux/mount.h> 19 #include <linux/mount.h>
20 #include <linux/namei.h> 20 #include <linux/namei.h>
21 #include <linux/uaccess.h> 21 #include <linux/uaccess.h>
22 #include <linux/mutex.h> 22 #include <linux/mutex.h>
23 #include <linux/spinlock.h> 23 #include <linux/spinlock.h>
24 #include <linux/list.h> 24 #include <linux/list.h>
25 #include <linux/completion.h> 25 #include <linux/completion.h>
26 #include <linux/file.h> 26 #include <linux/file.h>
27 #include <linux/magic.h> 27 #include <linux/magic.h>
28 #include <linux/fs_context.h> <<
29 #include <linux/fs_parser.h> <<
30 28
31 /* This is the range of ioctl() numbers we cla 29 /* This is the range of ioctl() numbers we claim as ours */
32 #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY 30 #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
33 #define AUTOFS_IOC_COUNT 32 31 #define AUTOFS_IOC_COUNT 32
34 32
35 #define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOF 33 #define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
36 #define AUTOFS_DEV_IOCTL_IOC_COUNT \ 34 #define AUTOFS_DEV_IOCTL_IOC_COUNT \
37 (AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD - A 35 (AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD - AUTOFS_DEV_IOCTL_VERSION_CMD)
38 36
39 #ifdef pr_fmt 37 #ifdef pr_fmt
40 #undef pr_fmt 38 #undef pr_fmt
41 #endif 39 #endif
42 #define pr_fmt(fmt) KBUILD_MODNAME ":pid:%d:%s 40 #define pr_fmt(fmt) KBUILD_MODNAME ":pid:%d:%s: " fmt, current->pid, __func__
43 41
44 extern struct file_system_type autofs_fs_type; 42 extern struct file_system_type autofs_fs_type;
45 43
46 /* 44 /*
47 * Unified info structure. This is pointed to 45 * Unified info structure. This is pointed to by both the dentry and
48 * inode structures. Each file in the filesys 46 * inode structures. Each file in the filesystem has an instance of this
49 * structure. It holds a reference to the den 47 * structure. It holds a reference to the dentry, so dentries are never
50 * flushed while the file exists. All name lo 48 * flushed while the file exists. All name lookups are dealt with at the
51 * dentry level, although the filesystem can i 49 * dentry level, although the filesystem can interfere in the validation
52 * process. Readdir is implemented by travers 50 * process. Readdir is implemented by traversing the dentry lists.
53 */ 51 */
54 struct autofs_info { 52 struct autofs_info {
55 struct dentry *dentry; 53 struct dentry *dentry;
>> 54 struct inode *inode;
>> 55
56 int flags; 56 int flags;
57 57
58 struct completion expire_complete; 58 struct completion expire_complete;
59 59
60 struct list_head active; 60 struct list_head active;
61 61
62 struct list_head expiring; 62 struct list_head expiring;
63 63
64 struct autofs_sb_info *sbi; 64 struct autofs_sb_info *sbi;
65 unsigned long exp_timeout; <<
66 unsigned long last_used; 65 unsigned long last_used;
67 int count; 66 int count;
68 67
69 kuid_t uid; 68 kuid_t uid;
70 kgid_t gid; 69 kgid_t gid;
71 struct rcu_head rcu; 70 struct rcu_head rcu;
72 }; 71 };
73 72
74 #define AUTOFS_INF_EXPIRING (1<<0) /* dent 73 #define AUTOFS_INF_EXPIRING (1<<0) /* dentry in the process of expiring */
75 #define AUTOFS_INF_WANT_EXPIRE (1<<1) /* the 74 #define AUTOFS_INF_WANT_EXPIRE (1<<1) /* the dentry is being considered
76 * for 75 * for expiry, so RCU_walk is
77 * not 76 * not permitted. If it progresses to
78 * actu 77 * actual expiry attempt, the flag is
79 * not 78 * not cleared when EXPIRING is set -
80 * in t 79 * in that case it gets cleared only
81 * when 80 * when it comes to clearing EXPIRING.
82 */ 81 */
83 #define AUTOFS_INF_PENDING (1<<2) /* dent 82 #define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */
84 83
85 #define AUTOFS_INF_EXPIRE_SET (1<<3) /* per- <<
86 this <<
87 */ <<
88 struct autofs_wait_queue { 84 struct autofs_wait_queue {
89 wait_queue_head_t queue; 85 wait_queue_head_t queue;
90 struct autofs_wait_queue *next; 86 struct autofs_wait_queue *next;
91 autofs_wqt_t wait_queue_token; 87 autofs_wqt_t wait_queue_token;
92 /* We use the following to see what we 88 /* We use the following to see what we are waiting for */
93 struct qstr name; 89 struct qstr name;
94 u32 offset; <<
95 u32 dev; 90 u32 dev;
96 u64 ino; 91 u64 ino;
97 kuid_t uid; 92 kuid_t uid;
98 kgid_t gid; 93 kgid_t gid;
99 pid_t pid; 94 pid_t pid;
100 pid_t tgid; 95 pid_t tgid;
101 /* This is for status reporting upon r 96 /* This is for status reporting upon return */
102 int status; 97 int status;
103 unsigned int wait_ctr; 98 unsigned int wait_ctr;
104 }; 99 };
105 100
106 #define AUTOFS_SBI_MAGIC 0x6d4a556d 101 #define AUTOFS_SBI_MAGIC 0x6d4a556d
107 102
108 #define AUTOFS_SBI_CATATONIC 0x0001 103 #define AUTOFS_SBI_CATATONIC 0x0001
109 #define AUTOFS_SBI_STRICTEXPIRE 0x0002 104 #define AUTOFS_SBI_STRICTEXPIRE 0x0002
110 #define AUTOFS_SBI_IGNORE 0x0004 105 #define AUTOFS_SBI_IGNORE 0x0004
111 106
112 struct autofs_sb_info { 107 struct autofs_sb_info {
113 u32 magic; 108 u32 magic;
114 int pipefd; 109 int pipefd;
115 struct file *pipe; 110 struct file *pipe;
116 struct pid *oz_pgrp; 111 struct pid *oz_pgrp;
117 int version; 112 int version;
118 int sub_version; 113 int sub_version;
119 int min_proto; 114 int min_proto;
120 int max_proto; 115 int max_proto;
121 unsigned int flags; 116 unsigned int flags;
122 unsigned long exp_timeout; 117 unsigned long exp_timeout;
123 unsigned int type; 118 unsigned int type;
124 struct super_block *sb; 119 struct super_block *sb;
125 struct mutex wq_mutex; 120 struct mutex wq_mutex;
126 struct mutex pipe_mutex; 121 struct mutex pipe_mutex;
127 spinlock_t fs_lock; 122 spinlock_t fs_lock;
128 struct autofs_wait_queue *queues; /* W 123 struct autofs_wait_queue *queues; /* Wait queue pointer */
129 spinlock_t lookup_lock; 124 spinlock_t lookup_lock;
130 struct list_head active_list; 125 struct list_head active_list;
131 struct list_head expiring_list; 126 struct list_head expiring_list;
132 struct rcu_head rcu; 127 struct rcu_head rcu;
133 }; 128 };
134 129
135 static inline struct autofs_sb_info *autofs_sb 130 static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb)
136 { 131 {
137 return (struct autofs_sb_info *)(sb->s 132 return (struct autofs_sb_info *)(sb->s_fs_info);
138 } 133 }
139 134
140 static inline struct autofs_info *autofs_dentr 135 static inline struct autofs_info *autofs_dentry_ino(struct dentry *dentry)
141 { 136 {
142 return (struct autofs_info *)(dentry-> 137 return (struct autofs_info *)(dentry->d_fsdata);
143 } 138 }
144 139
145 /* autofs_oz_mode(): do we see the man behind 140 /* autofs_oz_mode(): do we see the man behind the curtain? (The
146 * processes which do manipulations for us in 141 * processes which do manipulations for us in user space sees the raw
147 * filesystem without "magic".) 142 * filesystem without "magic".)
148 */ 143 */
149 static inline int autofs_oz_mode(struct autofs 144 static inline int autofs_oz_mode(struct autofs_sb_info *sbi)
150 { 145 {
151 return ((sbi->flags & AUTOFS_SBI_CATAT 146 return ((sbi->flags & AUTOFS_SBI_CATATONIC) ||
152 task_pgrp(current) == sbi->oz 147 task_pgrp(current) == sbi->oz_pgrp);
153 } 148 }
154 149
155 static inline bool autofs_empty(struct autofs_ <<
156 { <<
157 return ino->count < 2; <<
158 } <<
159 <<
160 struct inode *autofs_get_inode(struct super_bl 150 struct inode *autofs_get_inode(struct super_block *, umode_t);
161 void autofs_free_ino(struct autofs_info *); 151 void autofs_free_ino(struct autofs_info *);
162 152
163 /* Expiration */ 153 /* Expiration */
164 int is_autofs_dentry(struct dentry *); 154 int is_autofs_dentry(struct dentry *);
165 int autofs_expire_wait(const struct path *path 155 int autofs_expire_wait(const struct path *path, int rcu_walk);
166 int autofs_expire_run(struct super_block *, st 156 int autofs_expire_run(struct super_block *, struct vfsmount *,
167 struct autofs_sb_info *, 157 struct autofs_sb_info *,
168 struct autofs_packet_exp 158 struct autofs_packet_expire __user *);
169 int autofs_do_expire_multi(struct super_block 159 int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
170 struct autofs_sb_in 160 struct autofs_sb_info *sbi, unsigned int how);
171 int autofs_expire_multi(struct super_block *, 161 int autofs_expire_multi(struct super_block *, struct vfsmount *,
172 struct autofs_sb_info 162 struct autofs_sb_info *, int __user *);
173 163
174 /* Device node initialization */ 164 /* Device node initialization */
175 165
176 int autofs_dev_ioctl_init(void); 166 int autofs_dev_ioctl_init(void);
177 void autofs_dev_ioctl_exit(void); 167 void autofs_dev_ioctl_exit(void);
178 168
179 /* Operations structures */ 169 /* Operations structures */
180 170
181 extern const struct inode_operations autofs_sy 171 extern const struct inode_operations autofs_symlink_inode_operations;
182 extern const struct inode_operations autofs_di 172 extern const struct inode_operations autofs_dir_inode_operations;
183 extern const struct file_operations autofs_dir 173 extern const struct file_operations autofs_dir_operations;
184 extern const struct file_operations autofs_roo 174 extern const struct file_operations autofs_root_operations;
185 extern const struct dentry_operations autofs_d 175 extern const struct dentry_operations autofs_dentry_operations;
186 176
187 /* VFS automount flags management functions */ 177 /* VFS automount flags management functions */
188 static inline void __managed_dentry_set_manage 178 static inline void __managed_dentry_set_managed(struct dentry *dentry)
189 { 179 {
190 dentry->d_flags |= (DCACHE_NEED_AUTOMO 180 dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
191 } 181 }
192 182
193 static inline void managed_dentry_set_managed( 183 static inline void managed_dentry_set_managed(struct dentry *dentry)
194 { 184 {
195 spin_lock(&dentry->d_lock); 185 spin_lock(&dentry->d_lock);
196 __managed_dentry_set_managed(dentry); 186 __managed_dentry_set_managed(dentry);
197 spin_unlock(&dentry->d_lock); 187 spin_unlock(&dentry->d_lock);
198 } 188 }
199 189
200 static inline void __managed_dentry_clear_mana 190 static inline void __managed_dentry_clear_managed(struct dentry *dentry)
201 { 191 {
202 dentry->d_flags &= ~(DCACHE_NEED_AUTOM 192 dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
203 } 193 }
204 194
205 static inline void managed_dentry_clear_manage 195 static inline void managed_dentry_clear_managed(struct dentry *dentry)
206 { 196 {
207 spin_lock(&dentry->d_lock); 197 spin_lock(&dentry->d_lock);
208 __managed_dentry_clear_managed(dentry) 198 __managed_dentry_clear_managed(dentry);
209 spin_unlock(&dentry->d_lock); 199 spin_unlock(&dentry->d_lock);
210 } 200 }
211 201
212 /* Initializing function */ 202 /* Initializing function */
213 203
214 extern const struct fs_parameter_spec autofs_p !! 204 int autofs_fill_super(struct super_block *, void *, int);
215 int autofs_init_fs_context(struct fs_context * <<
216 struct autofs_info *autofs_new_ino(struct auto 205 struct autofs_info *autofs_new_ino(struct autofs_sb_info *);
217 void autofs_clean_ino(struct autofs_info *); 206 void autofs_clean_ino(struct autofs_info *);
218 207
219 static inline int autofs_check_pipe(struct fil !! 208 static inline int autofs_prepare_pipe(struct file *pipe)
220 { 209 {
221 if (!(pipe->f_mode & FMODE_CAN_WRITE)) 210 if (!(pipe->f_mode & FMODE_CAN_WRITE))
222 return -EINVAL; 211 return -EINVAL;
223 if (!S_ISFIFO(file_inode(pipe)->i_mode 212 if (!S_ISFIFO(file_inode(pipe)->i_mode))
224 return -EINVAL; 213 return -EINVAL;
225 return 0; <<
226 } <<
227 <<
228 static inline void autofs_set_packet_pipe_flag <<
229 { <<
230 /* We want a packet pipe */ 214 /* We want a packet pipe */
231 pipe->f_flags |= O_DIRECT; 215 pipe->f_flags |= O_DIRECT;
232 /* We don't expect -EAGAIN */ 216 /* We don't expect -EAGAIN */
233 pipe->f_flags &= ~O_NONBLOCK; 217 pipe->f_flags &= ~O_NONBLOCK;
234 } <<
235 <<
236 static inline int autofs_prepare_pipe(struct f <<
237 { <<
238 int ret = autofs_check_pipe(pipe); <<
239 if (ret < 0) <<
240 return ret; <<
241 autofs_set_packet_pipe_flags(pipe); <<
242 return 0; 218 return 0;
243 } 219 }
244 220
245 /* Queue management functions */ 221 /* Queue management functions */
246 222
247 int autofs_wait(struct autofs_sb_info *, 223 int autofs_wait(struct autofs_sb_info *,
248 const struct path *, enum aut 224 const struct path *, enum autofs_notify);
249 int autofs_wait_release(struct autofs_sb_info 225 int autofs_wait_release(struct autofs_sb_info *, autofs_wqt_t, int);
250 void autofs_catatonic_mode(struct autofs_sb_in 226 void autofs_catatonic_mode(struct autofs_sb_info *);
251 227
252 static inline u32 autofs_get_dev(struct autofs 228 static inline u32 autofs_get_dev(struct autofs_sb_info *sbi)
253 { 229 {
254 return new_encode_dev(sbi->sb->s_dev); 230 return new_encode_dev(sbi->sb->s_dev);
255 } 231 }
256 232
257 static inline u64 autofs_get_ino(struct autofs 233 static inline u64 autofs_get_ino(struct autofs_sb_info *sbi)
258 { 234 {
259 return d_inode(sbi->sb->s_root)->i_ino 235 return d_inode(sbi->sb->s_root)->i_ino;
260 } 236 }
261 237
262 static inline void __autofs_add_expiring(struc 238 static inline void __autofs_add_expiring(struct dentry *dentry)
263 { 239 {
264 struct autofs_sb_info *sbi = autofs_sb 240 struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb);
265 struct autofs_info *ino = autofs_dentr 241 struct autofs_info *ino = autofs_dentry_ino(dentry);
266 242
267 if (ino) { 243 if (ino) {
268 if (list_empty(&ino->expiring) 244 if (list_empty(&ino->expiring))
269 list_add(&ino->expirin 245 list_add(&ino->expiring, &sbi->expiring_list);
270 } 246 }
271 } 247 }
272 248
273 static inline void autofs_add_expiring(struct 249 static inline void autofs_add_expiring(struct dentry *dentry)
274 { 250 {
275 struct autofs_sb_info *sbi = autofs_sb 251 struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb);
276 struct autofs_info *ino = autofs_dentr 252 struct autofs_info *ino = autofs_dentry_ino(dentry);
277 253
278 if (ino) { 254 if (ino) {
279 spin_lock(&sbi->lookup_lock); 255 spin_lock(&sbi->lookup_lock);
280 if (list_empty(&ino->expiring) 256 if (list_empty(&ino->expiring))
281 list_add(&ino->expirin 257 list_add(&ino->expiring, &sbi->expiring_list);
282 spin_unlock(&sbi->lookup_lock) 258 spin_unlock(&sbi->lookup_lock);
283 } 259 }
284 } 260 }
285 261
286 static inline void autofs_del_expiring(struct 262 static inline void autofs_del_expiring(struct dentry *dentry)
287 { 263 {
288 struct autofs_sb_info *sbi = autofs_sb 264 struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb);
289 struct autofs_info *ino = autofs_dentr 265 struct autofs_info *ino = autofs_dentry_ino(dentry);
290 266
291 if (ino) { 267 if (ino) {
292 spin_lock(&sbi->lookup_lock); 268 spin_lock(&sbi->lookup_lock);
293 if (!list_empty(&ino->expiring 269 if (!list_empty(&ino->expiring))
294 list_del_init(&ino->ex 270 list_del_init(&ino->expiring);
295 spin_unlock(&sbi->lookup_lock) 271 spin_unlock(&sbi->lookup_lock);
296 } 272 }
297 } 273 }
298 274
299 void autofs_kill_sb(struct super_block *); 275 void autofs_kill_sb(struct super_block *);
300 276
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