Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/proc/base.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | * | |
6 | * proc base directory handling functions | |
7 | * | |
8 | * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. | |
9 | * Instead of using magical inumbers to determine the kind of object | |
10 | * we allocate and fill in-core inodes upon lookup. They don't even | |
11 | * go into icache. We cache the reference to task_struct upon lookup too. | |
12 | * Eventually it should become a filesystem in its own. We don't use the | |
13 | * rest of procfs anymore. | |
e070ad49 ML |
14 | * |
15 | * | |
16 | * Changelog: | |
17 | * 17-Jan-2005 | |
18 | * Allan Bezerra | |
19 | * Bruna Moreira <bruna.moreira@indt.org.br> | |
20 | * Edjard Mota <edjard.mota@indt.org.br> | |
21 | * Ilias Biris <ilias.biris@indt.org.br> | |
22 | * Mauricio Lin <mauricio.lin@indt.org.br> | |
23 | * | |
24 | * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT | |
25 | * | |
26 | * A new process specific entry (smaps) included in /proc. It shows the | |
27 | * size of rss for each memory area. The maps entry lacks information | |
28 | * about physical memory size (rss) for each mapped file, i.e., | |
29 | * rss information for executables and library files. | |
30 | * This additional information is useful for any tools that need to know | |
31 | * about physical memory consumption for a process specific library. | |
32 | * | |
33 | * Changelog: | |
34 | * 21-Feb-2005 | |
35 | * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT | |
36 | * Pud inclusion in the page table walking. | |
37 | * | |
38 | * ChangeLog: | |
39 | * 10-Mar-2005 | |
40 | * 10LE Instituto Nokia de Tecnologia - INdT: | |
41 | * A better way to walks through the page table as suggested by Hugh Dickins. | |
42 | * | |
43 | * Simo Piiroinen <simo.piiroinen@nokia.com>: | |
44 | * Smaps information related to shared, private, clean and dirty pages. | |
45 | * | |
46 | * Paul Mundt <paul.mundt@nokia.com>: | |
47 | * Overall revision about smaps. | |
1da177e4 LT |
48 | */ |
49 | ||
50 | #include <asm/uaccess.h> | |
51 | ||
52 | #include <linux/config.h> | |
53 | #include <linux/errno.h> | |
54 | #include <linux/time.h> | |
55 | #include <linux/proc_fs.h> | |
56 | #include <linux/stat.h> | |
57 | #include <linux/init.h> | |
16f7e0fe | 58 | #include <linux/capability.h> |
1da177e4 LT |
59 | #include <linux/file.h> |
60 | #include <linux/string.h> | |
61 | #include <linux/seq_file.h> | |
62 | #include <linux/namei.h> | |
63 | #include <linux/namespace.h> | |
64 | #include <linux/mm.h> | |
65 | #include <linux/smp_lock.h> | |
b835996f | 66 | #include <linux/rcupdate.h> |
1da177e4 LT |
67 | #include <linux/kallsyms.h> |
68 | #include <linux/mount.h> | |
69 | #include <linux/security.h> | |
70 | #include <linux/ptrace.h> | |
71 | #include <linux/seccomp.h> | |
72 | #include <linux/cpuset.h> | |
73 | #include <linux/audit.h> | |
5addc5dd | 74 | #include <linux/poll.h> |
1da177e4 LT |
75 | #include "internal.h" |
76 | ||
0f2fe20f EB |
77 | /* NOTE: |
78 | * Implementing inode permission operations in /proc is almost | |
79 | * certainly an error. Permission checks need to happen during | |
80 | * each system call not at open time. The reason is that most of | |
81 | * what we wish to check for permissions in /proc varies at runtime. | |
82 | * | |
83 | * The classic example of a problem is opening file descriptors | |
84 | * in /proc for a task before it execs a suid executable. | |
85 | */ | |
86 | ||
1da177e4 LT |
87 | /* |
88 | * For hysterical raisins we keep the same inumbers as in the old procfs. | |
89 | * Feel free to change the macro below - just keep the range distinct from | |
90 | * inumbers of the rest of procfs (currently those are in 0x0000--0xffff). | |
91 | * As soon as we'll get a separate superblock we will be able to forget | |
92 | * about magical ranges too. | |
93 | */ | |
94 | ||
95 | #define fake_ino(pid,ino) (((pid)<<16)|(ino)) | |
96 | ||
97 | enum pid_directory_inos { | |
98 | PROC_TGID_INO = 2, | |
99 | PROC_TGID_TASK, | |
100 | PROC_TGID_STATUS, | |
101 | PROC_TGID_MEM, | |
102 | #ifdef CONFIG_SECCOMP | |
103 | PROC_TGID_SECCOMP, | |
104 | #endif | |
105 | PROC_TGID_CWD, | |
106 | PROC_TGID_ROOT, | |
107 | PROC_TGID_EXE, | |
108 | PROC_TGID_FD, | |
109 | PROC_TGID_ENVIRON, | |
110 | PROC_TGID_AUXV, | |
111 | PROC_TGID_CMDLINE, | |
112 | PROC_TGID_STAT, | |
113 | PROC_TGID_STATM, | |
114 | PROC_TGID_MAPS, | |
6e21c8f1 | 115 | PROC_TGID_NUMA_MAPS, |
1da177e4 | 116 | PROC_TGID_MOUNTS, |
b4629fe2 | 117 | PROC_TGID_MOUNTSTATS, |
1da177e4 | 118 | PROC_TGID_WCHAN, |
63c6764c | 119 | #ifdef CONFIG_MMU |
e070ad49 | 120 | PROC_TGID_SMAPS, |
63c6764c | 121 | #endif |
1da177e4 LT |
122 | #ifdef CONFIG_SCHEDSTATS |
123 | PROC_TGID_SCHEDSTAT, | |
124 | #endif | |
125 | #ifdef CONFIG_CPUSETS | |
126 | PROC_TGID_CPUSET, | |
127 | #endif | |
128 | #ifdef CONFIG_SECURITY | |
129 | PROC_TGID_ATTR, | |
130 | PROC_TGID_ATTR_CURRENT, | |
131 | PROC_TGID_ATTR_PREV, | |
132 | PROC_TGID_ATTR_EXEC, | |
133 | PROC_TGID_ATTR_FSCREATE, | |
4eb582cf | 134 | PROC_TGID_ATTR_KEYCREATE, |
1da177e4 LT |
135 | #endif |
136 | #ifdef CONFIG_AUDITSYSCALL | |
137 | PROC_TGID_LOGINUID, | |
138 | #endif | |
1da177e4 LT |
139 | PROC_TGID_OOM_SCORE, |
140 | PROC_TGID_OOM_ADJUST, | |
141 | PROC_TID_INO, | |
142 | PROC_TID_STATUS, | |
143 | PROC_TID_MEM, | |
144 | #ifdef CONFIG_SECCOMP | |
145 | PROC_TID_SECCOMP, | |
146 | #endif | |
147 | PROC_TID_CWD, | |
148 | PROC_TID_ROOT, | |
149 | PROC_TID_EXE, | |
150 | PROC_TID_FD, | |
151 | PROC_TID_ENVIRON, | |
152 | PROC_TID_AUXV, | |
153 | PROC_TID_CMDLINE, | |
154 | PROC_TID_STAT, | |
155 | PROC_TID_STATM, | |
156 | PROC_TID_MAPS, | |
6e21c8f1 | 157 | PROC_TID_NUMA_MAPS, |
1da177e4 | 158 | PROC_TID_MOUNTS, |
b4629fe2 | 159 | PROC_TID_MOUNTSTATS, |
1da177e4 | 160 | PROC_TID_WCHAN, |
63c6764c | 161 | #ifdef CONFIG_MMU |
e070ad49 | 162 | PROC_TID_SMAPS, |
63c6764c | 163 | #endif |
1da177e4 LT |
164 | #ifdef CONFIG_SCHEDSTATS |
165 | PROC_TID_SCHEDSTAT, | |
166 | #endif | |
167 | #ifdef CONFIG_CPUSETS | |
168 | PROC_TID_CPUSET, | |
169 | #endif | |
170 | #ifdef CONFIG_SECURITY | |
171 | PROC_TID_ATTR, | |
172 | PROC_TID_ATTR_CURRENT, | |
173 | PROC_TID_ATTR_PREV, | |
174 | PROC_TID_ATTR_EXEC, | |
175 | PROC_TID_ATTR_FSCREATE, | |
4eb582cf | 176 | PROC_TID_ATTR_KEYCREATE, |
1da177e4 LT |
177 | #endif |
178 | #ifdef CONFIG_AUDITSYSCALL | |
179 | PROC_TID_LOGINUID, | |
180 | #endif | |
1da177e4 LT |
181 | PROC_TID_OOM_SCORE, |
182 | PROC_TID_OOM_ADJUST, | |
5e21ccb1 MS |
183 | |
184 | /* Add new entries before this */ | |
185 | PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */ | |
1da177e4 LT |
186 | }; |
187 | ||
8578cea7 EB |
188 | /* Worst case buffer size needed for holding an integer. */ |
189 | #define PROC_NUMBUF 10 | |
190 | ||
1da177e4 LT |
191 | struct pid_entry { |
192 | int type; | |
193 | int len; | |
194 | char *name; | |
195 | mode_t mode; | |
196 | }; | |
197 | ||
198 | #define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)} | |
199 | ||
200 | static struct pid_entry tgid_base_stuff[] = { | |
201 | E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO), | |
202 | E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), | |
203 | E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR), | |
204 | E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR), | |
205 | E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO), | |
206 | E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), | |
207 | E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO), | |
208 | E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO), | |
209 | E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO), | |
6e21c8f1 CL |
210 | #ifdef CONFIG_NUMA |
211 | E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), | |
212 | #endif | |
1da177e4 LT |
213 | E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), |
214 | #ifdef CONFIG_SECCOMP | |
215 | E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), | |
216 | #endif | |
217 | E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO), | |
218 | E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO), | |
219 | E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO), | |
220 | E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO), | |
b4629fe2 | 221 | E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR), |
63c6764c | 222 | #ifdef CONFIG_MMU |
e070ad49 | 223 | E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO), |
63c6764c | 224 | #endif |
1da177e4 LT |
225 | #ifdef CONFIG_SECURITY |
226 | E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), | |
227 | #endif | |
228 | #ifdef CONFIG_KALLSYMS | |
229 | E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO), | |
230 | #endif | |
231 | #ifdef CONFIG_SCHEDSTATS | |
232 | E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO), | |
233 | #endif | |
234 | #ifdef CONFIG_CPUSETS | |
235 | E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO), | |
236 | #endif | |
237 | E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), | |
238 | E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR), | |
239 | #ifdef CONFIG_AUDITSYSCALL | |
240 | E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), | |
241 | #endif | |
242 | {0,0,NULL,0} | |
243 | }; | |
244 | static struct pid_entry tid_base_stuff[] = { | |
245 | E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), | |
246 | E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR), | |
247 | E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR), | |
248 | E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO), | |
249 | E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), | |
250 | E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO), | |
251 | E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO), | |
252 | E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO), | |
6e21c8f1 CL |
253 | #ifdef CONFIG_NUMA |
254 | E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), | |
255 | #endif | |
1da177e4 LT |
256 | E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), |
257 | #ifdef CONFIG_SECCOMP | |
258 | E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), | |
259 | #endif | |
260 | E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO), | |
261 | E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO), | |
262 | E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO), | |
263 | E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO), | |
63c6764c | 264 | #ifdef CONFIG_MMU |
e070ad49 | 265 | E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO), |
63c6764c | 266 | #endif |
1da177e4 LT |
267 | #ifdef CONFIG_SECURITY |
268 | E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), | |
269 | #endif | |
270 | #ifdef CONFIG_KALLSYMS | |
271 | E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO), | |
272 | #endif | |
273 | #ifdef CONFIG_SCHEDSTATS | |
274 | E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO), | |
275 | #endif | |
276 | #ifdef CONFIG_CPUSETS | |
277 | E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO), | |
278 | #endif | |
279 | E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), | |
280 | E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR), | |
281 | #ifdef CONFIG_AUDITSYSCALL | |
282 | E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), | |
283 | #endif | |
284 | {0,0,NULL,0} | |
285 | }; | |
286 | ||
287 | #ifdef CONFIG_SECURITY | |
288 | static struct pid_entry tgid_attr_stuff[] = { | |
289 | E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), | |
290 | E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), | |
291 | E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), | |
292 | E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), | |
4eb582cf | 293 | E(PROC_TGID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO), |
1da177e4 LT |
294 | {0,0,NULL,0} |
295 | }; | |
296 | static struct pid_entry tid_attr_stuff[] = { | |
297 | E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), | |
298 | E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), | |
299 | E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), | |
300 | E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), | |
4eb582cf | 301 | E(PROC_TID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO), |
1da177e4 LT |
302 | {0,0,NULL,0} |
303 | }; | |
304 | #endif | |
305 | ||
306 | #undef E | |
307 | ||
308 | static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) | |
309 | { | |
99f89551 EB |
310 | struct task_struct *task = get_proc_task(inode); |
311 | struct files_struct *files = NULL; | |
1da177e4 | 312 | struct file *file; |
aed7a6c4 | 313 | int fd = proc_fd(inode); |
1da177e4 | 314 | |
99f89551 EB |
315 | if (task) { |
316 | files = get_files_struct(task); | |
317 | put_task_struct(task); | |
318 | } | |
1da177e4 | 319 | if (files) { |
ca99c1da DS |
320 | /* |
321 | * We are not taking a ref to the file structure, so we must | |
322 | * hold ->file_lock. | |
323 | */ | |
324 | spin_lock(&files->file_lock); | |
1da177e4 LT |
325 | file = fcheck_files(files, fd); |
326 | if (file) { | |
327 | *mnt = mntget(file->f_vfsmnt); | |
328 | *dentry = dget(file->f_dentry); | |
ca99c1da | 329 | spin_unlock(&files->file_lock); |
1da177e4 LT |
330 | put_files_struct(files); |
331 | return 0; | |
332 | } | |
ca99c1da | 333 | spin_unlock(&files->file_lock); |
1da177e4 LT |
334 | put_files_struct(files); |
335 | } | |
336 | return -ENOENT; | |
337 | } | |
338 | ||
0494f6ec | 339 | static struct fs_struct *get_fs_struct(struct task_struct *task) |
1da177e4 LT |
340 | { |
341 | struct fs_struct *fs; | |
0494f6ec MS |
342 | task_lock(task); |
343 | fs = task->fs; | |
1da177e4 LT |
344 | if(fs) |
345 | atomic_inc(&fs->count); | |
0494f6ec MS |
346 | task_unlock(task); |
347 | return fs; | |
348 | } | |
349 | ||
99f89551 EB |
350 | static int get_nr_threads(struct task_struct *tsk) |
351 | { | |
352 | /* Must be called with the rcu_read_lock held */ | |
353 | unsigned long flags; | |
354 | int count = 0; | |
355 | ||
356 | if (lock_task_sighand(tsk, &flags)) { | |
357 | count = atomic_read(&tsk->signal->count); | |
358 | unlock_task_sighand(tsk, &flags); | |
359 | } | |
360 | return count; | |
361 | } | |
362 | ||
0494f6ec MS |
363 | static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) |
364 | { | |
99f89551 EB |
365 | struct task_struct *task = get_proc_task(inode); |
366 | struct fs_struct *fs = NULL; | |
0494f6ec | 367 | int result = -ENOENT; |
99f89551 EB |
368 | |
369 | if (task) { | |
370 | fs = get_fs_struct(task); | |
371 | put_task_struct(task); | |
372 | } | |
1da177e4 LT |
373 | if (fs) { |
374 | read_lock(&fs->lock); | |
375 | *mnt = mntget(fs->pwdmnt); | |
376 | *dentry = dget(fs->pwd); | |
377 | read_unlock(&fs->lock); | |
378 | result = 0; | |
379 | put_fs_struct(fs); | |
380 | } | |
381 | return result; | |
382 | } | |
383 | ||
384 | static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) | |
385 | { | |
99f89551 EB |
386 | struct task_struct *task = get_proc_task(inode); |
387 | struct fs_struct *fs = NULL; | |
1da177e4 | 388 | int result = -ENOENT; |
99f89551 EB |
389 | |
390 | if (task) { | |
391 | fs = get_fs_struct(task); | |
392 | put_task_struct(task); | |
393 | } | |
1da177e4 LT |
394 | if (fs) { |
395 | read_lock(&fs->lock); | |
396 | *mnt = mntget(fs->rootmnt); | |
397 | *dentry = dget(fs->root); | |
398 | read_unlock(&fs->lock); | |
399 | result = 0; | |
400 | put_fs_struct(fs); | |
401 | } | |
402 | return result; | |
403 | } | |
404 | ||
405 | #define MAY_PTRACE(task) \ | |
406 | (task == current || \ | |
407 | (task->parent == current && \ | |
408 | (task->ptrace & PT_PTRACED) && \ | |
409 | (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ | |
410 | security_ptrace(current,task) == 0)) | |
411 | ||
1da177e4 LT |
412 | static int proc_pid_environ(struct task_struct *task, char * buffer) |
413 | { | |
414 | int res = 0; | |
415 | struct mm_struct *mm = get_task_mm(task); | |
416 | if (mm) { | |
417 | unsigned int len = mm->env_end - mm->env_start; | |
418 | if (len > PAGE_SIZE) | |
419 | len = PAGE_SIZE; | |
420 | res = access_process_vm(task, mm->env_start, buffer, len, 0); | |
ab8d11be | 421 | if (!ptrace_may_attach(task)) |
1da177e4 LT |
422 | res = -ESRCH; |
423 | mmput(mm); | |
424 | } | |
425 | return res; | |
426 | } | |
427 | ||
428 | static int proc_pid_cmdline(struct task_struct *task, char * buffer) | |
429 | { | |
430 | int res = 0; | |
431 | unsigned int len; | |
432 | struct mm_struct *mm = get_task_mm(task); | |
433 | if (!mm) | |
434 | goto out; | |
435 | if (!mm->arg_end) | |
436 | goto out_mm; /* Shh! No looking before we're done */ | |
437 | ||
438 | len = mm->arg_end - mm->arg_start; | |
439 | ||
440 | if (len > PAGE_SIZE) | |
441 | len = PAGE_SIZE; | |
442 | ||
443 | res = access_process_vm(task, mm->arg_start, buffer, len, 0); | |
444 | ||
445 | // If the nul at the end of args has been overwritten, then | |
446 | // assume application is using setproctitle(3). | |
447 | if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { | |
448 | len = strnlen(buffer, res); | |
449 | if (len < res) { | |
450 | res = len; | |
451 | } else { | |
452 | len = mm->env_end - mm->env_start; | |
453 | if (len > PAGE_SIZE - res) | |
454 | len = PAGE_SIZE - res; | |
455 | res += access_process_vm(task, mm->env_start, buffer+res, len, 0); | |
456 | res = strnlen(buffer, res); | |
457 | } | |
458 | } | |
459 | out_mm: | |
460 | mmput(mm); | |
461 | out: | |
462 | return res; | |
463 | } | |
464 | ||
465 | static int proc_pid_auxv(struct task_struct *task, char *buffer) | |
466 | { | |
467 | int res = 0; | |
468 | struct mm_struct *mm = get_task_mm(task); | |
469 | if (mm) { | |
470 | unsigned int nwords = 0; | |
471 | do | |
472 | nwords += 2; | |
473 | while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ | |
474 | res = nwords * sizeof(mm->saved_auxv[0]); | |
475 | if (res > PAGE_SIZE) | |
476 | res = PAGE_SIZE; | |
477 | memcpy(buffer, mm->saved_auxv, res); | |
478 | mmput(mm); | |
479 | } | |
480 | return res; | |
481 | } | |
482 | ||
483 | ||
484 | #ifdef CONFIG_KALLSYMS | |
485 | /* | |
486 | * Provides a wchan file via kallsyms in a proper one-value-per-file format. | |
487 | * Returns the resolved symbol. If that fails, simply return the address. | |
488 | */ | |
489 | static int proc_pid_wchan(struct task_struct *task, char *buffer) | |
490 | { | |
491 | char *modname; | |
492 | const char *sym_name; | |
493 | unsigned long wchan, size, offset; | |
494 | char namebuf[KSYM_NAME_LEN+1]; | |
495 | ||
496 | wchan = get_wchan(task); | |
497 | ||
498 | sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); | |
499 | if (sym_name) | |
500 | return sprintf(buffer, "%s", sym_name); | |
501 | return sprintf(buffer, "%lu", wchan); | |
502 | } | |
503 | #endif /* CONFIG_KALLSYMS */ | |
504 | ||
505 | #ifdef CONFIG_SCHEDSTATS | |
506 | /* | |
507 | * Provides /proc/PID/schedstat | |
508 | */ | |
509 | static int proc_pid_schedstat(struct task_struct *task, char *buffer) | |
510 | { | |
511 | return sprintf(buffer, "%lu %lu %lu\n", | |
512 | task->sched_info.cpu_time, | |
513 | task->sched_info.run_delay, | |
514 | task->sched_info.pcnt); | |
515 | } | |
516 | #endif | |
517 | ||
518 | /* The badness from the OOM killer */ | |
519 | unsigned long badness(struct task_struct *p, unsigned long uptime); | |
520 | static int proc_oom_score(struct task_struct *task, char *buffer) | |
521 | { | |
522 | unsigned long points; | |
523 | struct timespec uptime; | |
524 | ||
525 | do_posix_clock_monotonic_gettime(&uptime); | |
526 | points = badness(task, uptime.tv_sec); | |
527 | return sprintf(buffer, "%lu\n", points); | |
528 | } | |
529 | ||
530 | /************************************************************************/ | |
531 | /* Here the fs part begins */ | |
532 | /************************************************************************/ | |
533 | ||
534 | /* permission checks */ | |
778c1144 | 535 | static int proc_fd_access_allowed(struct inode *inode) |
1da177e4 | 536 | { |
778c1144 EB |
537 | struct task_struct *task; |
538 | int allowed = 0; | |
539 | /* Allow access to a task's file descriptors if either we may | |
540 | * use ptrace attach to the process and find out that | |
541 | * information, or if the task cannot possibly be ptraced | |
542 | * allow access if we have the proper capability. | |
543 | */ | |
544 | task = get_proc_task(inode); | |
545 | if (task == current) | |
546 | allowed = 1; | |
547 | if (task && !allowed) { | |
548 | int alive; | |
1da177e4 | 549 | |
778c1144 EB |
550 | task_lock(task); |
551 | alive = !!task->mm; | |
552 | task_unlock(task); | |
553 | if (alive) | |
554 | /* For a living task obey ptrace_may_attach */ | |
555 | allowed = ptrace_may_attach(task); | |
556 | else | |
557 | /* For a special task simply check the capability */ | |
558 | allowed = capable(CAP_SYS_PTRACE); | |
1da177e4 | 559 | } |
778c1144 EB |
560 | if (task) |
561 | put_task_struct(task); | |
562 | return allowed; | |
1da177e4 LT |
563 | } |
564 | ||
1da177e4 | 565 | extern struct seq_operations mounts_op; |
5addc5dd AV |
566 | struct proc_mounts { |
567 | struct seq_file m; | |
568 | int event; | |
569 | }; | |
570 | ||
1da177e4 LT |
571 | static int mounts_open(struct inode *inode, struct file *file) |
572 | { | |
99f89551 EB |
573 | struct task_struct *task = get_proc_task(inode); |
574 | struct namespace *namespace = NULL; | |
5addc5dd AV |
575 | struct proc_mounts *p; |
576 | int ret = -EINVAL; | |
1da177e4 | 577 | |
99f89551 EB |
578 | if (task) { |
579 | task_lock(task); | |
580 | namespace = task->namespace; | |
581 | if (namespace) | |
582 | get_namespace(namespace); | |
583 | task_unlock(task); | |
584 | put_task_struct(task); | |
585 | } | |
5addc5dd AV |
586 | |
587 | if (namespace) { | |
588 | ret = -ENOMEM; | |
589 | p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); | |
590 | if (p) { | |
591 | file->private_data = &p->m; | |
592 | ret = seq_open(file, &mounts_op); | |
593 | if (!ret) { | |
594 | p->m.private = namespace; | |
595 | p->event = namespace->event; | |
596 | return 0; | |
597 | } | |
598 | kfree(p); | |
1da177e4 | 599 | } |
5addc5dd | 600 | put_namespace(namespace); |
1da177e4 LT |
601 | } |
602 | return ret; | |
603 | } | |
604 | ||
605 | static int mounts_release(struct inode *inode, struct file *file) | |
606 | { | |
607 | struct seq_file *m = file->private_data; | |
608 | struct namespace *namespace = m->private; | |
609 | put_namespace(namespace); | |
610 | return seq_release(inode, file); | |
611 | } | |
612 | ||
5addc5dd AV |
613 | static unsigned mounts_poll(struct file *file, poll_table *wait) |
614 | { | |
615 | struct proc_mounts *p = file->private_data; | |
616 | struct namespace *ns = p->m.private; | |
617 | unsigned res = 0; | |
618 | ||
619 | poll_wait(file, &ns->poll, wait); | |
620 | ||
621 | spin_lock(&vfsmount_lock); | |
622 | if (p->event != ns->event) { | |
623 | p->event = ns->event; | |
624 | res = POLLERR; | |
625 | } | |
626 | spin_unlock(&vfsmount_lock); | |
627 | ||
628 | return res; | |
629 | } | |
630 | ||
1da177e4 LT |
631 | static struct file_operations proc_mounts_operations = { |
632 | .open = mounts_open, | |
633 | .read = seq_read, | |
634 | .llseek = seq_lseek, | |
635 | .release = mounts_release, | |
5addc5dd | 636 | .poll = mounts_poll, |
1da177e4 LT |
637 | }; |
638 | ||
b4629fe2 CL |
639 | extern struct seq_operations mountstats_op; |
640 | static int mountstats_open(struct inode *inode, struct file *file) | |
641 | { | |
b4629fe2 CL |
642 | int ret = seq_open(file, &mountstats_op); |
643 | ||
644 | if (!ret) { | |
645 | struct seq_file *m = file->private_data; | |
99f89551 EB |
646 | struct namespace *namespace = NULL; |
647 | struct task_struct *task = get_proc_task(inode); | |
648 | ||
649 | if (task) { | |
650 | task_lock(task); | |
651 | namespace = task->namespace; | |
652 | if (namespace) | |
653 | get_namespace(namespace); | |
654 | task_unlock(task); | |
655 | put_task_struct(task); | |
656 | } | |
b4629fe2 CL |
657 | |
658 | if (namespace) | |
659 | m->private = namespace; | |
660 | else { | |
661 | seq_release(inode, file); | |
662 | ret = -EINVAL; | |
663 | } | |
664 | } | |
665 | return ret; | |
666 | } | |
667 | ||
668 | static struct file_operations proc_mountstats_operations = { | |
669 | .open = mountstats_open, | |
670 | .read = seq_read, | |
671 | .llseek = seq_lseek, | |
672 | .release = mounts_release, | |
673 | }; | |
674 | ||
1da177e4 LT |
675 | #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ |
676 | ||
677 | static ssize_t proc_info_read(struct file * file, char __user * buf, | |
678 | size_t count, loff_t *ppos) | |
679 | { | |
680 | struct inode * inode = file->f_dentry->d_inode; | |
681 | unsigned long page; | |
682 | ssize_t length; | |
99f89551 EB |
683 | struct task_struct *task = get_proc_task(inode); |
684 | ||
685 | length = -ESRCH; | |
686 | if (!task) | |
687 | goto out_no_task; | |
1da177e4 LT |
688 | |
689 | if (count > PROC_BLOCK_SIZE) | |
690 | count = PROC_BLOCK_SIZE; | |
99f89551 EB |
691 | |
692 | length = -ENOMEM; | |
1da177e4 | 693 | if (!(page = __get_free_page(GFP_KERNEL))) |
99f89551 | 694 | goto out; |
1da177e4 LT |
695 | |
696 | length = PROC_I(inode)->op.proc_read(task, (char*)page); | |
697 | ||
698 | if (length >= 0) | |
699 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
700 | free_page(page); | |
99f89551 EB |
701 | out: |
702 | put_task_struct(task); | |
703 | out_no_task: | |
1da177e4 LT |
704 | return length; |
705 | } | |
706 | ||
707 | static struct file_operations proc_info_file_operations = { | |
708 | .read = proc_info_read, | |
709 | }; | |
710 | ||
711 | static int mem_open(struct inode* inode, struct file* file) | |
712 | { | |
713 | file->private_data = (void*)((long)current->self_exec_id); | |
714 | return 0; | |
715 | } | |
716 | ||
717 | static ssize_t mem_read(struct file * file, char __user * buf, | |
718 | size_t count, loff_t *ppos) | |
719 | { | |
99f89551 | 720 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
721 | char *page; |
722 | unsigned long src = *ppos; | |
723 | int ret = -ESRCH; | |
724 | struct mm_struct *mm; | |
725 | ||
99f89551 EB |
726 | if (!task) |
727 | goto out_no_task; | |
728 | ||
ab8d11be | 729 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
1da177e4 LT |
730 | goto out; |
731 | ||
732 | ret = -ENOMEM; | |
733 | page = (char *)__get_free_page(GFP_USER); | |
734 | if (!page) | |
735 | goto out; | |
736 | ||
737 | ret = 0; | |
738 | ||
739 | mm = get_task_mm(task); | |
740 | if (!mm) | |
741 | goto out_free; | |
742 | ||
743 | ret = -EIO; | |
744 | ||
745 | if (file->private_data != (void*)((long)current->self_exec_id)) | |
746 | goto out_put; | |
747 | ||
748 | ret = 0; | |
749 | ||
750 | while (count > 0) { | |
751 | int this_len, retval; | |
752 | ||
753 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
754 | retval = access_process_vm(task, src, page, this_len, 0); | |
ab8d11be | 755 | if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { |
1da177e4 LT |
756 | if (!ret) |
757 | ret = -EIO; | |
758 | break; | |
759 | } | |
760 | ||
761 | if (copy_to_user(buf, page, retval)) { | |
762 | ret = -EFAULT; | |
763 | break; | |
764 | } | |
765 | ||
766 | ret += retval; | |
767 | src += retval; | |
768 | buf += retval; | |
769 | count -= retval; | |
770 | } | |
771 | *ppos = src; | |
772 | ||
773 | out_put: | |
774 | mmput(mm); | |
775 | out_free: | |
776 | free_page((unsigned long) page); | |
777 | out: | |
99f89551 EB |
778 | put_task_struct(task); |
779 | out_no_task: | |
1da177e4 LT |
780 | return ret; |
781 | } | |
782 | ||
783 | #define mem_write NULL | |
784 | ||
785 | #ifndef mem_write | |
786 | /* This is a security hazard */ | |
787 | static ssize_t mem_write(struct file * file, const char * buf, | |
788 | size_t count, loff_t *ppos) | |
789 | { | |
790 | int copied = 0; | |
791 | char *page; | |
99f89551 | 792 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
793 | unsigned long dst = *ppos; |
794 | ||
99f89551 EB |
795 | copied = -ESRCH; |
796 | if (!task) | |
797 | goto out_no_task; | |
798 | ||
ab8d11be | 799 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
99f89551 | 800 | goto out; |
1da177e4 | 801 | |
99f89551 | 802 | copied = -ENOMEM; |
1da177e4 LT |
803 | page = (char *)__get_free_page(GFP_USER); |
804 | if (!page) | |
99f89551 | 805 | goto out; |
1da177e4 LT |
806 | |
807 | while (count > 0) { | |
808 | int this_len, retval; | |
809 | ||
810 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
811 | if (copy_from_user(page, buf, this_len)) { | |
812 | copied = -EFAULT; | |
813 | break; | |
814 | } | |
815 | retval = access_process_vm(task, dst, page, this_len, 1); | |
816 | if (!retval) { | |
817 | if (!copied) | |
818 | copied = -EIO; | |
819 | break; | |
820 | } | |
821 | copied += retval; | |
822 | buf += retval; | |
823 | dst += retval; | |
824 | count -= retval; | |
825 | } | |
826 | *ppos = dst; | |
827 | free_page((unsigned long) page); | |
99f89551 EB |
828 | out: |
829 | put_task_struct(task); | |
830 | out_no_task: | |
1da177e4 LT |
831 | return copied; |
832 | } | |
833 | #endif | |
834 | ||
835 | static loff_t mem_lseek(struct file * file, loff_t offset, int orig) | |
836 | { | |
837 | switch (orig) { | |
838 | case 0: | |
839 | file->f_pos = offset; | |
840 | break; | |
841 | case 1: | |
842 | file->f_pos += offset; | |
843 | break; | |
844 | default: | |
845 | return -EINVAL; | |
846 | } | |
847 | force_successful_syscall_return(); | |
848 | return file->f_pos; | |
849 | } | |
850 | ||
851 | static struct file_operations proc_mem_operations = { | |
852 | .llseek = mem_lseek, | |
853 | .read = mem_read, | |
854 | .write = mem_write, | |
855 | .open = mem_open, | |
856 | }; | |
857 | ||
858 | static ssize_t oom_adjust_read(struct file *file, char __user *buf, | |
859 | size_t count, loff_t *ppos) | |
860 | { | |
99f89551 | 861 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
8578cea7 | 862 | char buffer[PROC_NUMBUF]; |
1da177e4 | 863 | size_t len; |
99f89551 | 864 | int oom_adjust; |
1da177e4 LT |
865 | loff_t __ppos = *ppos; |
866 | ||
99f89551 EB |
867 | if (!task) |
868 | return -ESRCH; | |
869 | oom_adjust = task->oomkilladj; | |
870 | put_task_struct(task); | |
871 | ||
8578cea7 | 872 | len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); |
1da177e4 LT |
873 | if (__ppos >= len) |
874 | return 0; | |
875 | if (count > len-__ppos) | |
876 | count = len-__ppos; | |
877 | if (copy_to_user(buf, buffer + __ppos, count)) | |
878 | return -EFAULT; | |
879 | *ppos = __ppos + count; | |
880 | return count; | |
881 | } | |
882 | ||
883 | static ssize_t oom_adjust_write(struct file *file, const char __user *buf, | |
884 | size_t count, loff_t *ppos) | |
885 | { | |
99f89551 | 886 | struct task_struct *task; |
8578cea7 | 887 | char buffer[PROC_NUMBUF], *end; |
1da177e4 LT |
888 | int oom_adjust; |
889 | ||
890 | if (!capable(CAP_SYS_RESOURCE)) | |
891 | return -EPERM; | |
8578cea7 EB |
892 | memset(buffer, 0, sizeof(buffer)); |
893 | if (count > sizeof(buffer) - 1) | |
894 | count = sizeof(buffer) - 1; | |
1da177e4 LT |
895 | if (copy_from_user(buffer, buf, count)) |
896 | return -EFAULT; | |
897 | oom_adjust = simple_strtol(buffer, &end, 0); | |
79befd0c | 898 | if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE) |
1da177e4 LT |
899 | return -EINVAL; |
900 | if (*end == '\n') | |
901 | end++; | |
99f89551 EB |
902 | task = get_proc_task(file->f_dentry->d_inode); |
903 | if (!task) | |
904 | return -ESRCH; | |
1da177e4 | 905 | task->oomkilladj = oom_adjust; |
99f89551 | 906 | put_task_struct(task); |
1da177e4 LT |
907 | if (end - buffer == 0) |
908 | return -EIO; | |
909 | return end - buffer; | |
910 | } | |
911 | ||
912 | static struct file_operations proc_oom_adjust_operations = { | |
913 | .read = oom_adjust_read, | |
914 | .write = oom_adjust_write, | |
915 | }; | |
916 | ||
1da177e4 LT |
917 | #ifdef CONFIG_AUDITSYSCALL |
918 | #define TMPBUFLEN 21 | |
919 | static ssize_t proc_loginuid_read(struct file * file, char __user * buf, | |
920 | size_t count, loff_t *ppos) | |
921 | { | |
922 | struct inode * inode = file->f_dentry->d_inode; | |
99f89551 | 923 | struct task_struct *task = get_proc_task(inode); |
1da177e4 LT |
924 | ssize_t length; |
925 | char tmpbuf[TMPBUFLEN]; | |
926 | ||
99f89551 EB |
927 | if (!task) |
928 | return -ESRCH; | |
1da177e4 LT |
929 | length = scnprintf(tmpbuf, TMPBUFLEN, "%u", |
930 | audit_get_loginuid(task->audit_context)); | |
99f89551 | 931 | put_task_struct(task); |
1da177e4 LT |
932 | return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); |
933 | } | |
934 | ||
935 | static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, | |
936 | size_t count, loff_t *ppos) | |
937 | { | |
938 | struct inode * inode = file->f_dentry->d_inode; | |
939 | char *page, *tmp; | |
940 | ssize_t length; | |
1da177e4 LT |
941 | uid_t loginuid; |
942 | ||
943 | if (!capable(CAP_AUDIT_CONTROL)) | |
944 | return -EPERM; | |
945 | ||
13b41b09 | 946 | if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) |
1da177e4 LT |
947 | return -EPERM; |
948 | ||
e0182909 AV |
949 | if (count >= PAGE_SIZE) |
950 | count = PAGE_SIZE - 1; | |
1da177e4 LT |
951 | |
952 | if (*ppos != 0) { | |
953 | /* No partial writes. */ | |
954 | return -EINVAL; | |
955 | } | |
956 | page = (char*)__get_free_page(GFP_USER); | |
957 | if (!page) | |
958 | return -ENOMEM; | |
959 | length = -EFAULT; | |
960 | if (copy_from_user(page, buf, count)) | |
961 | goto out_free_page; | |
962 | ||
e0182909 | 963 | page[count] = '\0'; |
1da177e4 LT |
964 | loginuid = simple_strtoul(page, &tmp, 10); |
965 | if (tmp == page) { | |
966 | length = -EINVAL; | |
967 | goto out_free_page; | |
968 | ||
969 | } | |
99f89551 | 970 | length = audit_set_loginuid(current, loginuid); |
1da177e4 LT |
971 | if (likely(length == 0)) |
972 | length = count; | |
973 | ||
974 | out_free_page: | |
975 | free_page((unsigned long) page); | |
976 | return length; | |
977 | } | |
978 | ||
979 | static struct file_operations proc_loginuid_operations = { | |
980 | .read = proc_loginuid_read, | |
981 | .write = proc_loginuid_write, | |
982 | }; | |
983 | #endif | |
984 | ||
985 | #ifdef CONFIG_SECCOMP | |
986 | static ssize_t seccomp_read(struct file *file, char __user *buf, | |
987 | size_t count, loff_t *ppos) | |
988 | { | |
99f89551 | 989 | struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
990 | char __buf[20]; |
991 | loff_t __ppos = *ppos; | |
992 | size_t len; | |
993 | ||
99f89551 EB |
994 | if (!tsk) |
995 | return -ESRCH; | |
1da177e4 LT |
996 | /* no need to print the trailing zero, so use only len */ |
997 | len = sprintf(__buf, "%u\n", tsk->seccomp.mode); | |
99f89551 | 998 | put_task_struct(tsk); |
1da177e4 LT |
999 | if (__ppos >= len) |
1000 | return 0; | |
1001 | if (count > len - __ppos) | |
1002 | count = len - __ppos; | |
1003 | if (copy_to_user(buf, __buf + __ppos, count)) | |
1004 | return -EFAULT; | |
1005 | *ppos = __ppos + count; | |
1006 | return count; | |
1007 | } | |
1008 | ||
1009 | static ssize_t seccomp_write(struct file *file, const char __user *buf, | |
1010 | size_t count, loff_t *ppos) | |
1011 | { | |
99f89551 | 1012 | struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
1013 | char __buf[20], *end; |
1014 | unsigned int seccomp_mode; | |
99f89551 EB |
1015 | ssize_t result; |
1016 | ||
1017 | result = -ESRCH; | |
1018 | if (!tsk) | |
1019 | goto out_no_task; | |
1da177e4 LT |
1020 | |
1021 | /* can set it only once to be even more secure */ | |
99f89551 | 1022 | result = -EPERM; |
1da177e4 | 1023 | if (unlikely(tsk->seccomp.mode)) |
99f89551 | 1024 | goto out; |
1da177e4 | 1025 | |
99f89551 | 1026 | result = -EFAULT; |
1da177e4 LT |
1027 | memset(__buf, 0, sizeof(__buf)); |
1028 | count = min(count, sizeof(__buf) - 1); | |
1029 | if (copy_from_user(__buf, buf, count)) | |
99f89551 EB |
1030 | goto out; |
1031 | ||
1da177e4 LT |
1032 | seccomp_mode = simple_strtoul(__buf, &end, 0); |
1033 | if (*end == '\n') | |
1034 | end++; | |
99f89551 | 1035 | result = -EINVAL; |
1da177e4 LT |
1036 | if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { |
1037 | tsk->seccomp.mode = seccomp_mode; | |
1038 | set_tsk_thread_flag(tsk, TIF_SECCOMP); | |
1039 | } else | |
99f89551 EB |
1040 | goto out; |
1041 | result = -EIO; | |
1da177e4 | 1042 | if (unlikely(!(end - __buf))) |
99f89551 EB |
1043 | goto out; |
1044 | result = end - __buf; | |
1045 | out: | |
1046 | put_task_struct(tsk); | |
1047 | out_no_task: | |
1048 | return result; | |
1da177e4 LT |
1049 | } |
1050 | ||
1051 | static struct file_operations proc_seccomp_operations = { | |
1052 | .read = seccomp_read, | |
1053 | .write = seccomp_write, | |
1054 | }; | |
1055 | #endif /* CONFIG_SECCOMP */ | |
1056 | ||
008b150a | 1057 | static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
1058 | { |
1059 | struct inode *inode = dentry->d_inode; | |
1060 | int error = -EACCES; | |
1061 | ||
1062 | /* We don't need a base pointer in the /proc filesystem */ | |
1063 | path_release(nd); | |
1064 | ||
778c1144 EB |
1065 | /* Are we allowed to snoop on the tasks file descriptors? */ |
1066 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 1067 | goto out; |
1da177e4 LT |
1068 | |
1069 | error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); | |
1070 | nd->last_type = LAST_BIND; | |
1071 | out: | |
008b150a | 1072 | return ERR_PTR(error); |
1da177e4 LT |
1073 | } |
1074 | ||
1075 | static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, | |
1076 | char __user *buffer, int buflen) | |
1077 | { | |
1078 | struct inode * inode; | |
1079 | char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; | |
1080 | int len; | |
1081 | ||
1082 | if (!tmp) | |
1083 | return -ENOMEM; | |
1084 | ||
1085 | inode = dentry->d_inode; | |
1086 | path = d_path(dentry, mnt, tmp, PAGE_SIZE); | |
1087 | len = PTR_ERR(path); | |
1088 | if (IS_ERR(path)) | |
1089 | goto out; | |
1090 | len = tmp + PAGE_SIZE - 1 - path; | |
1091 | ||
1092 | if (len > buflen) | |
1093 | len = buflen; | |
1094 | if (copy_to_user(buffer, path, len)) | |
1095 | len = -EFAULT; | |
1096 | out: | |
1097 | free_page((unsigned long)tmp); | |
1098 | return len; | |
1099 | } | |
1100 | ||
1101 | static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) | |
1102 | { | |
1103 | int error = -EACCES; | |
1104 | struct inode *inode = dentry->d_inode; | |
1105 | struct dentry *de; | |
1106 | struct vfsmount *mnt = NULL; | |
1107 | ||
778c1144 EB |
1108 | /* Are we allowed to snoop on the tasks file descriptors? */ |
1109 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 1110 | goto out; |
1da177e4 LT |
1111 | |
1112 | error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); | |
1113 | if (error) | |
1114 | goto out; | |
1115 | ||
1116 | error = do_proc_readlink(de, mnt, buffer, buflen); | |
1117 | dput(de); | |
1118 | mntput(mnt); | |
1119 | out: | |
1da177e4 LT |
1120 | return error; |
1121 | } | |
1122 | ||
1123 | static struct inode_operations proc_pid_link_inode_operations = { | |
1124 | .readlink = proc_pid_readlink, | |
1125 | .follow_link = proc_pid_follow_link | |
1126 | }; | |
1127 | ||
1da177e4 LT |
1128 | static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) |
1129 | { | |
5634708b EB |
1130 | struct dentry *dentry = filp->f_dentry; |
1131 | struct inode *inode = dentry->d_inode; | |
99f89551 | 1132 | struct task_struct *p = get_proc_task(inode); |
1da177e4 LT |
1133 | unsigned int fd, tid, ino; |
1134 | int retval; | |
8578cea7 | 1135 | char buf[PROC_NUMBUF]; |
1da177e4 | 1136 | struct files_struct * files; |
badf1662 | 1137 | struct fdtable *fdt; |
1da177e4 LT |
1138 | |
1139 | retval = -ENOENT; | |
99f89551 EB |
1140 | if (!p) |
1141 | goto out_no_task; | |
1da177e4 LT |
1142 | retval = 0; |
1143 | tid = p->pid; | |
1144 | ||
1145 | fd = filp->f_pos; | |
1146 | switch (fd) { | |
1147 | case 0: | |
1148 | if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) | |
1149 | goto out; | |
1150 | filp->f_pos++; | |
1151 | case 1: | |
5634708b | 1152 | ino = parent_ino(dentry); |
1da177e4 LT |
1153 | if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) |
1154 | goto out; | |
1155 | filp->f_pos++; | |
1156 | default: | |
1157 | files = get_files_struct(p); | |
1158 | if (!files) | |
1159 | goto out; | |
b835996f | 1160 | rcu_read_lock(); |
badf1662 | 1161 | fdt = files_fdtable(files); |
1da177e4 | 1162 | for (fd = filp->f_pos-2; |
badf1662 | 1163 | fd < fdt->max_fds; |
1da177e4 LT |
1164 | fd++, filp->f_pos++) { |
1165 | unsigned int i,j; | |
1166 | ||
1167 | if (!fcheck_files(files, fd)) | |
1168 | continue; | |
b835996f | 1169 | rcu_read_unlock(); |
1da177e4 | 1170 | |
8578cea7 | 1171 | j = PROC_NUMBUF; |
1da177e4 LT |
1172 | i = fd; |
1173 | do { | |
1174 | j--; | |
1175 | buf[j] = '0' + (i % 10); | |
1176 | i /= 10; | |
1177 | } while (i); | |
1178 | ||
1179 | ino = fake_ino(tid, PROC_TID_FD_DIR + fd); | |
8578cea7 | 1180 | if (filldir(dirent, buf+j, PROC_NUMBUF-j, fd+2, ino, DT_LNK) < 0) { |
b835996f | 1181 | rcu_read_lock(); |
1da177e4 LT |
1182 | break; |
1183 | } | |
b835996f | 1184 | rcu_read_lock(); |
1da177e4 | 1185 | } |
b835996f | 1186 | rcu_read_unlock(); |
1da177e4 LT |
1187 | put_files_struct(files); |
1188 | } | |
1189 | out: | |
99f89551 EB |
1190 | put_task_struct(p); |
1191 | out_no_task: | |
1da177e4 LT |
1192 | return retval; |
1193 | } | |
1194 | ||
1195 | static int proc_pident_readdir(struct file *filp, | |
1196 | void *dirent, filldir_t filldir, | |
1197 | struct pid_entry *ents, unsigned int nents) | |
1198 | { | |
1199 | int i; | |
1200 | int pid; | |
1201 | struct dentry *dentry = filp->f_dentry; | |
1202 | struct inode *inode = dentry->d_inode; | |
99f89551 | 1203 | struct task_struct *task = get_proc_task(inode); |
1da177e4 LT |
1204 | struct pid_entry *p; |
1205 | ino_t ino; | |
1206 | int ret; | |
1207 | ||
1208 | ret = -ENOENT; | |
99f89551 | 1209 | if (!task) |
1da177e4 LT |
1210 | goto out; |
1211 | ||
1212 | ret = 0; | |
99f89551 EB |
1213 | pid = task->pid; |
1214 | put_task_struct(task); | |
1da177e4 LT |
1215 | i = filp->f_pos; |
1216 | switch (i) { | |
1217 | case 0: | |
1218 | ino = inode->i_ino; | |
1219 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
1220 | goto out; | |
1221 | i++; | |
1222 | filp->f_pos++; | |
1223 | /* fall through */ | |
1224 | case 1: | |
1225 | ino = parent_ino(dentry); | |
1226 | if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) | |
1227 | goto out; | |
1228 | i++; | |
1229 | filp->f_pos++; | |
1230 | /* fall through */ | |
1231 | default: | |
1232 | i -= 2; | |
1233 | if (i >= nents) { | |
1234 | ret = 1; | |
1235 | goto out; | |
1236 | } | |
1237 | p = ents + i; | |
1238 | while (p->name) { | |
1239 | if (filldir(dirent, p->name, p->len, filp->f_pos, | |
1240 | fake_ino(pid, p->type), p->mode >> 12) < 0) | |
1241 | goto out; | |
1242 | filp->f_pos++; | |
1243 | p++; | |
1244 | } | |
1245 | } | |
1246 | ||
1247 | ret = 1; | |
1248 | out: | |
1249 | return ret; | |
1250 | } | |
1251 | ||
1252 | static int proc_tgid_base_readdir(struct file * filp, | |
1253 | void * dirent, filldir_t filldir) | |
1254 | { | |
1255 | return proc_pident_readdir(filp,dirent,filldir, | |
1256 | tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); | |
1257 | } | |
1258 | ||
1259 | static int proc_tid_base_readdir(struct file * filp, | |
1260 | void * dirent, filldir_t filldir) | |
1261 | { | |
1262 | return proc_pident_readdir(filp,dirent,filldir, | |
1263 | tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); | |
1264 | } | |
1265 | ||
1266 | /* building an inode */ | |
1267 | ||
1268 | static int task_dumpable(struct task_struct *task) | |
1269 | { | |
1270 | int dumpable = 0; | |
1271 | struct mm_struct *mm; | |
1272 | ||
1273 | task_lock(task); | |
1274 | mm = task->mm; | |
1275 | if (mm) | |
1276 | dumpable = mm->dumpable; | |
1277 | task_unlock(task); | |
d6e71144 AC |
1278 | if(dumpable == 1) |
1279 | return 1; | |
1280 | return 0; | |
1da177e4 LT |
1281 | } |
1282 | ||
1283 | ||
1284 | static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino) | |
1285 | { | |
1286 | struct inode * inode; | |
1287 | struct proc_inode *ei; | |
1288 | ||
1289 | /* We need a new inode */ | |
1290 | ||
1291 | inode = new_inode(sb); | |
1292 | if (!inode) | |
1293 | goto out; | |
1294 | ||
1295 | /* Common stuff */ | |
1296 | ei = PROC_I(inode); | |
1da177e4 LT |
1297 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1298 | inode->i_ino = fake_ino(task->pid, ino); | |
1299 | ||
1da177e4 LT |
1300 | /* |
1301 | * grab the reference to task. | |
1302 | */ | |
13b41b09 EB |
1303 | ei->pid = get_pid(task->pids[PIDTYPE_PID].pid); |
1304 | if (!ei->pid) | |
99f89551 EB |
1305 | goto out_unlock; |
1306 | ||
1da177e4 LT |
1307 | inode->i_uid = 0; |
1308 | inode->i_gid = 0; | |
87bfbf67 | 1309 | if (task_dumpable(task)) { |
1da177e4 LT |
1310 | inode->i_uid = task->euid; |
1311 | inode->i_gid = task->egid; | |
1312 | } | |
1313 | security_task_to_inode(task, inode); | |
1314 | ||
1315 | out: | |
1316 | return inode; | |
1317 | ||
1318 | out_unlock: | |
1da177e4 LT |
1319 | iput(inode); |
1320 | return NULL; | |
1321 | } | |
1322 | ||
1323 | /* dentry stuff */ | |
1324 | ||
1325 | /* | |
1326 | * Exceptional case: normally we are not allowed to unhash a busy | |
1327 | * directory. In this case, however, we can do it - no aliasing problems | |
1328 | * due to the way we treat inodes. | |
1329 | * | |
1330 | * Rewrite the inode's ownerships here because the owning task may have | |
1331 | * performed a setuid(), etc. | |
99f89551 EB |
1332 | * |
1333 | * Before the /proc/pid/status file was created the only way to read | |
1334 | * the effective uid of a /process was to stat /proc/pid. Reading | |
1335 | * /proc/pid/status is slow enough that procps and other packages | |
1336 | * kept stating /proc/pid. To keep the rules in /proc simple I have | |
1337 | * made this apply to all per process world readable and executable | |
1338 | * directories. | |
1da177e4 LT |
1339 | */ |
1340 | static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1341 | { | |
1342 | struct inode *inode = dentry->d_inode; | |
99f89551 EB |
1343 | struct task_struct *task = get_proc_task(inode); |
1344 | if (task) { | |
1345 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1346 | task_dumpable(task)) { | |
1da177e4 LT |
1347 | inode->i_uid = task->euid; |
1348 | inode->i_gid = task->egid; | |
1349 | } else { | |
1350 | inode->i_uid = 0; | |
1351 | inode->i_gid = 0; | |
1352 | } | |
1353 | security_task_to_inode(task, inode); | |
99f89551 | 1354 | put_task_struct(task); |
1da177e4 LT |
1355 | return 1; |
1356 | } | |
1357 | d_drop(dentry); | |
1358 | return 0; | |
1359 | } | |
1360 | ||
99f89551 EB |
1361 | static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) |
1362 | { | |
1363 | struct inode *inode = dentry->d_inode; | |
1364 | struct task_struct *task; | |
1365 | generic_fillattr(inode, stat); | |
1366 | ||
1367 | rcu_read_lock(); | |
1368 | stat->uid = 0; | |
1369 | stat->gid = 0; | |
1370 | task = pid_task(proc_pid(inode), PIDTYPE_PID); | |
1371 | if (task) { | |
1372 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1373 | task_dumpable(task)) { | |
1374 | stat->uid = task->euid; | |
1375 | stat->gid = task->egid; | |
1376 | } | |
1377 | } | |
1378 | rcu_read_unlock(); | |
1379 | return 0; | |
1380 | } | |
1381 | ||
1da177e4 LT |
1382 | static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) |
1383 | { | |
1384 | struct inode *inode = dentry->d_inode; | |
99f89551 | 1385 | struct task_struct *task = get_proc_task(inode); |
aed7a6c4 | 1386 | int fd = proc_fd(inode); |
1da177e4 LT |
1387 | struct files_struct *files; |
1388 | ||
99f89551 EB |
1389 | if (task) { |
1390 | files = get_files_struct(task); | |
1391 | if (files) { | |
1392 | rcu_read_lock(); | |
1393 | if (fcheck_files(files, fd)) { | |
1394 | rcu_read_unlock(); | |
1395 | put_files_struct(files); | |
1396 | if (task_dumpable(task)) { | |
1397 | inode->i_uid = task->euid; | |
1398 | inode->i_gid = task->egid; | |
1399 | } else { | |
1400 | inode->i_uid = 0; | |
1401 | inode->i_gid = 0; | |
1402 | } | |
1403 | security_task_to_inode(task, inode); | |
1404 | put_task_struct(task); | |
1405 | return 1; | |
1406 | } | |
b835996f | 1407 | rcu_read_unlock(); |
1da177e4 | 1408 | put_files_struct(files); |
1da177e4 | 1409 | } |
99f89551 | 1410 | put_task_struct(task); |
1da177e4 LT |
1411 | } |
1412 | d_drop(dentry); | |
1413 | return 0; | |
1414 | } | |
1415 | ||
1da177e4 LT |
1416 | static int pid_delete_dentry(struct dentry * dentry) |
1417 | { | |
1418 | /* Is the task we represent dead? | |
1419 | * If so, then don't put the dentry on the lru list, | |
1420 | * kill it immediately. | |
1421 | */ | |
13b41b09 | 1422 | return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; |
1da177e4 LT |
1423 | } |
1424 | ||
1425 | static struct dentry_operations tid_fd_dentry_operations = | |
1426 | { | |
1427 | .d_revalidate = tid_fd_revalidate, | |
1428 | .d_delete = pid_delete_dentry, | |
1429 | }; | |
1430 | ||
1431 | static struct dentry_operations pid_dentry_operations = | |
1432 | { | |
1433 | .d_revalidate = pid_revalidate, | |
1434 | .d_delete = pid_delete_dentry, | |
1435 | }; | |
1436 | ||
1da177e4 LT |
1437 | /* Lookups */ |
1438 | ||
1439 | static unsigned name_to_int(struct dentry *dentry) | |
1440 | { | |
1441 | const char *name = dentry->d_name.name; | |
1442 | int len = dentry->d_name.len; | |
1443 | unsigned n = 0; | |
1444 | ||
1445 | if (len > 1 && *name == '0') | |
1446 | goto out; | |
1447 | while (len-- > 0) { | |
1448 | unsigned c = *name++ - '0'; | |
1449 | if (c > 9) | |
1450 | goto out; | |
1451 | if (n >= (~0U-9)/10) | |
1452 | goto out; | |
1453 | n *= 10; | |
1454 | n += c; | |
1455 | } | |
1456 | return n; | |
1457 | out: | |
1458 | return ~0U; | |
1459 | } | |
1460 | ||
1461 | /* SMP-safe */ | |
1462 | static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) | |
1463 | { | |
99f89551 | 1464 | struct task_struct *task = get_proc_task(dir); |
1da177e4 | 1465 | unsigned fd = name_to_int(dentry); |
cd6a3ce9 | 1466 | struct dentry *result = ERR_PTR(-ENOENT); |
1da177e4 LT |
1467 | struct file * file; |
1468 | struct files_struct * files; | |
1469 | struct inode *inode; | |
1470 | struct proc_inode *ei; | |
1471 | ||
99f89551 EB |
1472 | if (!task) |
1473 | goto out_no_task; | |
1da177e4 LT |
1474 | if (fd == ~0U) |
1475 | goto out; | |
1da177e4 LT |
1476 | |
1477 | inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd); | |
1478 | if (!inode) | |
1479 | goto out; | |
1480 | ei = PROC_I(inode); | |
aed7a6c4 | 1481 | ei->fd = fd; |
1da177e4 LT |
1482 | files = get_files_struct(task); |
1483 | if (!files) | |
1484 | goto out_unlock; | |
1485 | inode->i_mode = S_IFLNK; | |
ca99c1da DS |
1486 | |
1487 | /* | |
1488 | * We are not taking a ref to the file structure, so we must | |
1489 | * hold ->file_lock. | |
1490 | */ | |
1491 | spin_lock(&files->file_lock); | |
1da177e4 LT |
1492 | file = fcheck_files(files, fd); |
1493 | if (!file) | |
1494 | goto out_unlock2; | |
1495 | if (file->f_mode & 1) | |
1496 | inode->i_mode |= S_IRUSR | S_IXUSR; | |
1497 | if (file->f_mode & 2) | |
1498 | inode->i_mode |= S_IWUSR | S_IXUSR; | |
ca99c1da | 1499 | spin_unlock(&files->file_lock); |
1da177e4 LT |
1500 | put_files_struct(files); |
1501 | inode->i_op = &proc_pid_link_inode_operations; | |
1502 | inode->i_size = 64; | |
1503 | ei->op.proc_get_link = proc_fd_link; | |
1504 | dentry->d_op = &tid_fd_dentry_operations; | |
1505 | d_add(dentry, inode); | |
cd6a3ce9 EB |
1506 | /* Close the race of the process dying before we return the dentry */ |
1507 | if (tid_fd_revalidate(dentry, NULL)) | |
1508 | result = NULL; | |
1509 | out: | |
99f89551 EB |
1510 | put_task_struct(task); |
1511 | out_no_task: | |
cd6a3ce9 | 1512 | return result; |
1da177e4 LT |
1513 | |
1514 | out_unlock2: | |
ca99c1da | 1515 | spin_unlock(&files->file_lock); |
1da177e4 LT |
1516 | put_files_struct(files); |
1517 | out_unlock: | |
1518 | iput(inode); | |
cd6a3ce9 | 1519 | goto out; |
1da177e4 LT |
1520 | } |
1521 | ||
1522 | static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); | |
1523 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); | |
6e66b52b | 1524 | static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); |
1da177e4 LT |
1525 | |
1526 | static struct file_operations proc_fd_operations = { | |
1527 | .read = generic_read_dir, | |
1528 | .readdir = proc_readfd, | |
1529 | }; | |
1530 | ||
1531 | static struct file_operations proc_task_operations = { | |
1532 | .read = generic_read_dir, | |
1533 | .readdir = proc_task_readdir, | |
1534 | }; | |
1535 | ||
1536 | /* | |
1537 | * proc directories can do almost nothing.. | |
1538 | */ | |
1539 | static struct inode_operations proc_fd_inode_operations = { | |
1540 | .lookup = proc_lookupfd, | |
1da177e4 LT |
1541 | }; |
1542 | ||
1543 | static struct inode_operations proc_task_inode_operations = { | |
1544 | .lookup = proc_task_lookup, | |
6e66b52b | 1545 | .getattr = proc_task_getattr, |
1da177e4 LT |
1546 | }; |
1547 | ||
1548 | #ifdef CONFIG_SECURITY | |
1549 | static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, | |
1550 | size_t count, loff_t *ppos) | |
1551 | { | |
1552 | struct inode * inode = file->f_dentry->d_inode; | |
1553 | unsigned long page; | |
1554 | ssize_t length; | |
99f89551 EB |
1555 | struct task_struct *task = get_proc_task(inode); |
1556 | ||
1557 | length = -ESRCH; | |
1558 | if (!task) | |
1559 | goto out_no_task; | |
1da177e4 LT |
1560 | |
1561 | if (count > PAGE_SIZE) | |
1562 | count = PAGE_SIZE; | |
99f89551 | 1563 | length = -ENOMEM; |
1da177e4 | 1564 | if (!(page = __get_free_page(GFP_KERNEL))) |
99f89551 | 1565 | goto out; |
1da177e4 LT |
1566 | |
1567 | length = security_getprocattr(task, | |
1568 | (char*)file->f_dentry->d_name.name, | |
1569 | (void*)page, count); | |
1570 | if (length >= 0) | |
1571 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
1572 | free_page(page); | |
99f89551 EB |
1573 | out: |
1574 | put_task_struct(task); | |
1575 | out_no_task: | |
1da177e4 LT |
1576 | return length; |
1577 | } | |
1578 | ||
1579 | static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, | |
1580 | size_t count, loff_t *ppos) | |
1581 | { | |
1582 | struct inode * inode = file->f_dentry->d_inode; | |
1583 | char *page; | |
1584 | ssize_t length; | |
99f89551 | 1585 | struct task_struct *task = get_proc_task(inode); |
1da177e4 | 1586 | |
99f89551 EB |
1587 | length = -ESRCH; |
1588 | if (!task) | |
1589 | goto out_no_task; | |
1da177e4 LT |
1590 | if (count > PAGE_SIZE) |
1591 | count = PAGE_SIZE; | |
99f89551 EB |
1592 | |
1593 | /* No partial writes. */ | |
1594 | length = -EINVAL; | |
1595 | if (*ppos != 0) | |
1596 | goto out; | |
1597 | ||
1598 | length = -ENOMEM; | |
1da177e4 LT |
1599 | page = (char*)__get_free_page(GFP_USER); |
1600 | if (!page) | |
99f89551 EB |
1601 | goto out; |
1602 | ||
1da177e4 LT |
1603 | length = -EFAULT; |
1604 | if (copy_from_user(page, buf, count)) | |
99f89551 | 1605 | goto out_free; |
1da177e4 LT |
1606 | |
1607 | length = security_setprocattr(task, | |
1608 | (char*)file->f_dentry->d_name.name, | |
1609 | (void*)page, count); | |
99f89551 | 1610 | out_free: |
1da177e4 | 1611 | free_page((unsigned long) page); |
99f89551 EB |
1612 | out: |
1613 | put_task_struct(task); | |
1614 | out_no_task: | |
1da177e4 LT |
1615 | return length; |
1616 | } | |
1617 | ||
1618 | static struct file_operations proc_pid_attr_operations = { | |
1619 | .read = proc_pid_attr_read, | |
1620 | .write = proc_pid_attr_write, | |
1621 | }; | |
1622 | ||
1623 | static struct file_operations proc_tid_attr_operations; | |
1624 | static struct inode_operations proc_tid_attr_inode_operations; | |
1625 | static struct file_operations proc_tgid_attr_operations; | |
1626 | static struct inode_operations proc_tgid_attr_inode_operations; | |
1627 | #endif | |
1628 | ||
1629 | /* SMP-safe */ | |
1630 | static struct dentry *proc_pident_lookup(struct inode *dir, | |
1631 | struct dentry *dentry, | |
1632 | struct pid_entry *ents) | |
1633 | { | |
1634 | struct inode *inode; | |
cd6a3ce9 | 1635 | struct dentry *error; |
99f89551 | 1636 | struct task_struct *task = get_proc_task(dir); |
1da177e4 LT |
1637 | struct pid_entry *p; |
1638 | struct proc_inode *ei; | |
1639 | ||
cd6a3ce9 | 1640 | error = ERR_PTR(-ENOENT); |
1da177e4 LT |
1641 | inode = NULL; |
1642 | ||
99f89551 EB |
1643 | if (!task) |
1644 | goto out_no_task; | |
1da177e4 LT |
1645 | |
1646 | for (p = ents; p->name; p++) { | |
1647 | if (p->len != dentry->d_name.len) | |
1648 | continue; | |
1649 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
1650 | break; | |
1651 | } | |
1652 | if (!p->name) | |
1653 | goto out; | |
1654 | ||
cd6a3ce9 | 1655 | error = ERR_PTR(-EINVAL); |
1da177e4 LT |
1656 | inode = proc_pid_make_inode(dir->i_sb, task, p->type); |
1657 | if (!inode) | |
1658 | goto out; | |
1659 | ||
1660 | ei = PROC_I(inode); | |
1661 | inode->i_mode = p->mode; | |
1662 | /* | |
1663 | * Yes, it does not scale. And it should not. Don't add | |
1664 | * new entries into /proc/<tgid>/ without very good reasons. | |
1665 | */ | |
1666 | switch(p->type) { | |
1667 | case PROC_TGID_TASK: | |
6e66b52b | 1668 | inode->i_nlink = 2; |
1da177e4 LT |
1669 | inode->i_op = &proc_task_inode_operations; |
1670 | inode->i_fop = &proc_task_operations; | |
1671 | break; | |
1672 | case PROC_TID_FD: | |
1673 | case PROC_TGID_FD: | |
1674 | inode->i_nlink = 2; | |
1675 | inode->i_op = &proc_fd_inode_operations; | |
1676 | inode->i_fop = &proc_fd_operations; | |
1677 | break; | |
1678 | case PROC_TID_EXE: | |
1679 | case PROC_TGID_EXE: | |
1680 | inode->i_op = &proc_pid_link_inode_operations; | |
1681 | ei->op.proc_get_link = proc_exe_link; | |
1682 | break; | |
1683 | case PROC_TID_CWD: | |
1684 | case PROC_TGID_CWD: | |
1685 | inode->i_op = &proc_pid_link_inode_operations; | |
1686 | ei->op.proc_get_link = proc_cwd_link; | |
1687 | break; | |
1688 | case PROC_TID_ROOT: | |
1689 | case PROC_TGID_ROOT: | |
1690 | inode->i_op = &proc_pid_link_inode_operations; | |
1691 | ei->op.proc_get_link = proc_root_link; | |
1692 | break; | |
1693 | case PROC_TID_ENVIRON: | |
1694 | case PROC_TGID_ENVIRON: | |
1695 | inode->i_fop = &proc_info_file_operations; | |
1696 | ei->op.proc_read = proc_pid_environ; | |
1697 | break; | |
1698 | case PROC_TID_AUXV: | |
1699 | case PROC_TGID_AUXV: | |
1700 | inode->i_fop = &proc_info_file_operations; | |
1701 | ei->op.proc_read = proc_pid_auxv; | |
1702 | break; | |
1703 | case PROC_TID_STATUS: | |
1704 | case PROC_TGID_STATUS: | |
1705 | inode->i_fop = &proc_info_file_operations; | |
1706 | ei->op.proc_read = proc_pid_status; | |
1707 | break; | |
1708 | case PROC_TID_STAT: | |
1709 | inode->i_fop = &proc_info_file_operations; | |
1710 | ei->op.proc_read = proc_tid_stat; | |
1711 | break; | |
1712 | case PROC_TGID_STAT: | |
1713 | inode->i_fop = &proc_info_file_operations; | |
1714 | ei->op.proc_read = proc_tgid_stat; | |
1715 | break; | |
1716 | case PROC_TID_CMDLINE: | |
1717 | case PROC_TGID_CMDLINE: | |
1718 | inode->i_fop = &proc_info_file_operations; | |
1719 | ei->op.proc_read = proc_pid_cmdline; | |
1720 | break; | |
1721 | case PROC_TID_STATM: | |
1722 | case PROC_TGID_STATM: | |
1723 | inode->i_fop = &proc_info_file_operations; | |
1724 | ei->op.proc_read = proc_pid_statm; | |
1725 | break; | |
1726 | case PROC_TID_MAPS: | |
1727 | case PROC_TGID_MAPS: | |
1728 | inode->i_fop = &proc_maps_operations; | |
1729 | break; | |
6e21c8f1 CL |
1730 | #ifdef CONFIG_NUMA |
1731 | case PROC_TID_NUMA_MAPS: | |
1732 | case PROC_TGID_NUMA_MAPS: | |
1733 | inode->i_fop = &proc_numa_maps_operations; | |
1734 | break; | |
1735 | #endif | |
1da177e4 LT |
1736 | case PROC_TID_MEM: |
1737 | case PROC_TGID_MEM: | |
1da177e4 LT |
1738 | inode->i_fop = &proc_mem_operations; |
1739 | break; | |
1740 | #ifdef CONFIG_SECCOMP | |
1741 | case PROC_TID_SECCOMP: | |
1742 | case PROC_TGID_SECCOMP: | |
1743 | inode->i_fop = &proc_seccomp_operations; | |
1744 | break; | |
1745 | #endif /* CONFIG_SECCOMP */ | |
1746 | case PROC_TID_MOUNTS: | |
1747 | case PROC_TGID_MOUNTS: | |
1748 | inode->i_fop = &proc_mounts_operations; | |
1749 | break; | |
63c6764c | 1750 | #ifdef CONFIG_MMU |
e070ad49 ML |
1751 | case PROC_TID_SMAPS: |
1752 | case PROC_TGID_SMAPS: | |
1753 | inode->i_fop = &proc_smaps_operations; | |
1754 | break; | |
63c6764c | 1755 | #endif |
b4629fe2 CL |
1756 | case PROC_TID_MOUNTSTATS: |
1757 | case PROC_TGID_MOUNTSTATS: | |
1758 | inode->i_fop = &proc_mountstats_operations; | |
1759 | break; | |
1da177e4 LT |
1760 | #ifdef CONFIG_SECURITY |
1761 | case PROC_TID_ATTR: | |
1762 | inode->i_nlink = 2; | |
1763 | inode->i_op = &proc_tid_attr_inode_operations; | |
1764 | inode->i_fop = &proc_tid_attr_operations; | |
1765 | break; | |
1766 | case PROC_TGID_ATTR: | |
1767 | inode->i_nlink = 2; | |
1768 | inode->i_op = &proc_tgid_attr_inode_operations; | |
1769 | inode->i_fop = &proc_tgid_attr_operations; | |
1770 | break; | |
1771 | case PROC_TID_ATTR_CURRENT: | |
1772 | case PROC_TGID_ATTR_CURRENT: | |
1773 | case PROC_TID_ATTR_PREV: | |
1774 | case PROC_TGID_ATTR_PREV: | |
1775 | case PROC_TID_ATTR_EXEC: | |
1776 | case PROC_TGID_ATTR_EXEC: | |
1777 | case PROC_TID_ATTR_FSCREATE: | |
1778 | case PROC_TGID_ATTR_FSCREATE: | |
4eb582cf ML |
1779 | case PROC_TID_ATTR_KEYCREATE: |
1780 | case PROC_TGID_ATTR_KEYCREATE: | |
1da177e4 LT |
1781 | inode->i_fop = &proc_pid_attr_operations; |
1782 | break; | |
1783 | #endif | |
1784 | #ifdef CONFIG_KALLSYMS | |
1785 | case PROC_TID_WCHAN: | |
1786 | case PROC_TGID_WCHAN: | |
1787 | inode->i_fop = &proc_info_file_operations; | |
1788 | ei->op.proc_read = proc_pid_wchan; | |
1789 | break; | |
1790 | #endif | |
1791 | #ifdef CONFIG_SCHEDSTATS | |
1792 | case PROC_TID_SCHEDSTAT: | |
1793 | case PROC_TGID_SCHEDSTAT: | |
1794 | inode->i_fop = &proc_info_file_operations; | |
1795 | ei->op.proc_read = proc_pid_schedstat; | |
1796 | break; | |
1797 | #endif | |
1798 | #ifdef CONFIG_CPUSETS | |
1799 | case PROC_TID_CPUSET: | |
1800 | case PROC_TGID_CPUSET: | |
1801 | inode->i_fop = &proc_cpuset_operations; | |
1802 | break; | |
1803 | #endif | |
1804 | case PROC_TID_OOM_SCORE: | |
1805 | case PROC_TGID_OOM_SCORE: | |
1806 | inode->i_fop = &proc_info_file_operations; | |
1807 | ei->op.proc_read = proc_oom_score; | |
1808 | break; | |
1809 | case PROC_TID_OOM_ADJUST: | |
1810 | case PROC_TGID_OOM_ADJUST: | |
1811 | inode->i_fop = &proc_oom_adjust_operations; | |
1812 | break; | |
1813 | #ifdef CONFIG_AUDITSYSCALL | |
1814 | case PROC_TID_LOGINUID: | |
1815 | case PROC_TGID_LOGINUID: | |
1816 | inode->i_fop = &proc_loginuid_operations; | |
1817 | break; | |
1818 | #endif | |
1819 | default: | |
1820 | printk("procfs: impossible type (%d)",p->type); | |
1821 | iput(inode); | |
cd6a3ce9 EB |
1822 | error = ERR_PTR(-EINVAL); |
1823 | goto out; | |
1da177e4 LT |
1824 | } |
1825 | dentry->d_op = &pid_dentry_operations; | |
1826 | d_add(dentry, inode); | |
cd6a3ce9 EB |
1827 | /* Close the race of the process dying before we return the dentry */ |
1828 | if (pid_revalidate(dentry, NULL)) | |
1829 | error = NULL; | |
1da177e4 | 1830 | out: |
99f89551 EB |
1831 | put_task_struct(task); |
1832 | out_no_task: | |
cd6a3ce9 | 1833 | return error; |
1da177e4 LT |
1834 | } |
1835 | ||
1836 | static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
1837 | return proc_pident_lookup(dir, dentry, tgid_base_stuff); | |
1838 | } | |
1839 | ||
1840 | static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
1841 | return proc_pident_lookup(dir, dentry, tid_base_stuff); | |
1842 | } | |
1843 | ||
1844 | static struct file_operations proc_tgid_base_operations = { | |
1845 | .read = generic_read_dir, | |
1846 | .readdir = proc_tgid_base_readdir, | |
1847 | }; | |
1848 | ||
1849 | static struct file_operations proc_tid_base_operations = { | |
1850 | .read = generic_read_dir, | |
1851 | .readdir = proc_tid_base_readdir, | |
1852 | }; | |
1853 | ||
1854 | static struct inode_operations proc_tgid_base_inode_operations = { | |
1855 | .lookup = proc_tgid_base_lookup, | |
99f89551 | 1856 | .getattr = pid_getattr, |
1da177e4 LT |
1857 | }; |
1858 | ||
1859 | static struct inode_operations proc_tid_base_inode_operations = { | |
1860 | .lookup = proc_tid_base_lookup, | |
99f89551 | 1861 | .getattr = pid_getattr, |
1da177e4 LT |
1862 | }; |
1863 | ||
1864 | #ifdef CONFIG_SECURITY | |
1865 | static int proc_tgid_attr_readdir(struct file * filp, | |
1866 | void * dirent, filldir_t filldir) | |
1867 | { | |
1868 | return proc_pident_readdir(filp,dirent,filldir, | |
1869 | tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff)); | |
1870 | } | |
1871 | ||
1872 | static int proc_tid_attr_readdir(struct file * filp, | |
1873 | void * dirent, filldir_t filldir) | |
1874 | { | |
1875 | return proc_pident_readdir(filp,dirent,filldir, | |
1876 | tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff)); | |
1877 | } | |
1878 | ||
1879 | static struct file_operations proc_tgid_attr_operations = { | |
1880 | .read = generic_read_dir, | |
1881 | .readdir = proc_tgid_attr_readdir, | |
1882 | }; | |
1883 | ||
1884 | static struct file_operations proc_tid_attr_operations = { | |
1885 | .read = generic_read_dir, | |
1886 | .readdir = proc_tid_attr_readdir, | |
1887 | }; | |
1888 | ||
1889 | static struct dentry *proc_tgid_attr_lookup(struct inode *dir, | |
1890 | struct dentry *dentry, struct nameidata *nd) | |
1891 | { | |
1892 | return proc_pident_lookup(dir, dentry, tgid_attr_stuff); | |
1893 | } | |
1894 | ||
1895 | static struct dentry *proc_tid_attr_lookup(struct inode *dir, | |
1896 | struct dentry *dentry, struct nameidata *nd) | |
1897 | { | |
1898 | return proc_pident_lookup(dir, dentry, tid_attr_stuff); | |
1899 | } | |
1900 | ||
1901 | static struct inode_operations proc_tgid_attr_inode_operations = { | |
1902 | .lookup = proc_tgid_attr_lookup, | |
99f89551 | 1903 | .getattr = pid_getattr, |
1da177e4 LT |
1904 | }; |
1905 | ||
1906 | static struct inode_operations proc_tid_attr_inode_operations = { | |
1907 | .lookup = proc_tid_attr_lookup, | |
99f89551 | 1908 | .getattr = pid_getattr, |
1da177e4 LT |
1909 | }; |
1910 | #endif | |
1911 | ||
1912 | /* | |
1913 | * /proc/self: | |
1914 | */ | |
1915 | static int proc_self_readlink(struct dentry *dentry, char __user *buffer, | |
1916 | int buflen) | |
1917 | { | |
8578cea7 | 1918 | char tmp[PROC_NUMBUF]; |
1da177e4 LT |
1919 | sprintf(tmp, "%d", current->tgid); |
1920 | return vfs_readlink(dentry,buffer,buflen,tmp); | |
1921 | } | |
1922 | ||
008b150a | 1923 | static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 | 1924 | { |
8578cea7 | 1925 | char tmp[PROC_NUMBUF]; |
1da177e4 | 1926 | sprintf(tmp, "%d", current->tgid); |
008b150a | 1927 | return ERR_PTR(vfs_follow_link(nd,tmp)); |
1da177e4 LT |
1928 | } |
1929 | ||
1930 | static struct inode_operations proc_self_inode_operations = { | |
1931 | .readlink = proc_self_readlink, | |
1932 | .follow_link = proc_self_follow_link, | |
1933 | }; | |
1934 | ||
1935 | /** | |
48e6484d EB |
1936 | * proc_flush_task - Remove dcache entries for @task from the /proc dcache. |
1937 | * | |
1938 | * @task: task that should be flushed. | |
1939 | * | |
1940 | * Looks in the dcache for | |
1941 | * /proc/@pid | |
1942 | * /proc/@tgid/task/@pid | |
1943 | * if either directory is present flushes it and all of it'ts children | |
1944 | * from the dcache. | |
1da177e4 | 1945 | * |
48e6484d EB |
1946 | * It is safe and reasonable to cache /proc entries for a task until |
1947 | * that task exits. After that they just clog up the dcache with | |
1948 | * useless entries, possibly causing useful dcache entries to be | |
1949 | * flushed instead. This routine is proved to flush those useless | |
1950 | * dcache entries at process exit time. | |
1da177e4 | 1951 | * |
48e6484d EB |
1952 | * NOTE: This routine is just an optimization so it does not guarantee |
1953 | * that no dcache entries will exist at process exit time it | |
1954 | * just makes it very unlikely that any will persist. | |
1da177e4 | 1955 | */ |
48e6484d | 1956 | void proc_flush_task(struct task_struct *task) |
1da177e4 | 1957 | { |
48e6484d | 1958 | struct dentry *dentry, *leader, *dir; |
8578cea7 | 1959 | char buf[PROC_NUMBUF]; |
48e6484d EB |
1960 | struct qstr name; |
1961 | ||
1962 | name.name = buf; | |
1963 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
1964 | dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
1965 | if (dentry) { | |
1966 | shrink_dcache_parent(dentry); | |
1967 | d_drop(dentry); | |
1968 | dput(dentry); | |
1969 | } | |
1da177e4 | 1970 | |
48e6484d EB |
1971 | if (thread_group_leader(task)) |
1972 | goto out; | |
1da177e4 | 1973 | |
48e6484d EB |
1974 | name.name = buf; |
1975 | name.len = snprintf(buf, sizeof(buf), "%d", task->tgid); | |
1976 | leader = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
1977 | if (!leader) | |
1978 | goto out; | |
1da177e4 | 1979 | |
48e6484d EB |
1980 | name.name = "task"; |
1981 | name.len = strlen(name.name); | |
1982 | dir = d_hash_and_lookup(leader, &name); | |
1983 | if (!dir) | |
1984 | goto out_put_leader; | |
1985 | ||
1986 | name.name = buf; | |
1987 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
1988 | dentry = d_hash_and_lookup(dir, &name); | |
1989 | if (dentry) { | |
1990 | shrink_dcache_parent(dentry); | |
1991 | d_drop(dentry); | |
1992 | dput(dentry); | |
1da177e4 | 1993 | } |
48e6484d EB |
1994 | |
1995 | dput(dir); | |
1996 | out_put_leader: | |
1997 | dput(leader); | |
1998 | out: | |
1999 | return; | |
1da177e4 LT |
2000 | } |
2001 | ||
2002 | /* SMP-safe */ | |
2003 | struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) | |
2004 | { | |
cd6a3ce9 | 2005 | struct dentry *result = ERR_PTR(-ENOENT); |
1da177e4 LT |
2006 | struct task_struct *task; |
2007 | struct inode *inode; | |
2008 | struct proc_inode *ei; | |
2009 | unsigned tgid; | |
1da177e4 LT |
2010 | |
2011 | if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) { | |
2012 | inode = new_inode(dir->i_sb); | |
2013 | if (!inode) | |
2014 | return ERR_PTR(-ENOMEM); | |
2015 | ei = PROC_I(inode); | |
2016 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
2017 | inode->i_ino = fake_ino(0, PROC_TGID_INO); | |
2018 | ei->pde = NULL; | |
2019 | inode->i_mode = S_IFLNK|S_IRWXUGO; | |
2020 | inode->i_uid = inode->i_gid = 0; | |
2021 | inode->i_size = 64; | |
2022 | inode->i_op = &proc_self_inode_operations; | |
2023 | d_add(dentry, inode); | |
2024 | return NULL; | |
2025 | } | |
2026 | tgid = name_to_int(dentry); | |
2027 | if (tgid == ~0U) | |
2028 | goto out; | |
2029 | ||
de758734 | 2030 | rcu_read_lock(); |
1da177e4 LT |
2031 | task = find_task_by_pid(tgid); |
2032 | if (task) | |
2033 | get_task_struct(task); | |
de758734 | 2034 | rcu_read_unlock(); |
1da177e4 LT |
2035 | if (!task) |
2036 | goto out; | |
2037 | ||
2038 | inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO); | |
cd6a3ce9 EB |
2039 | if (!inode) |
2040 | goto out_put_task; | |
1da177e4 | 2041 | |
1da177e4 LT |
2042 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; |
2043 | inode->i_op = &proc_tgid_base_inode_operations; | |
2044 | inode->i_fop = &proc_tgid_base_operations; | |
1da177e4 | 2045 | inode->i_flags|=S_IMMUTABLE; |
bcf88e11 DD |
2046 | #ifdef CONFIG_SECURITY |
2047 | inode->i_nlink = 5; | |
2048 | #else | |
2049 | inode->i_nlink = 4; | |
2050 | #endif | |
1da177e4 | 2051 | |
48e6484d | 2052 | dentry->d_op = &pid_dentry_operations; |
1da177e4 | 2053 | |
1da177e4 | 2054 | d_add(dentry, inode); |
cd6a3ce9 EB |
2055 | /* Close the race of the process dying before we return the dentry */ |
2056 | if (pid_revalidate(dentry, NULL)) | |
2057 | result = NULL; | |
1da177e4 | 2058 | |
cd6a3ce9 | 2059 | out_put_task: |
1da177e4 | 2060 | put_task_struct(task); |
1da177e4 | 2061 | out: |
cd6a3ce9 | 2062 | return result; |
1da177e4 LT |
2063 | } |
2064 | ||
2065 | /* SMP-safe */ | |
2066 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) | |
2067 | { | |
cd6a3ce9 | 2068 | struct dentry *result = ERR_PTR(-ENOENT); |
1da177e4 | 2069 | struct task_struct *task; |
99f89551 | 2070 | struct task_struct *leader = get_proc_task(dir); |
1da177e4 LT |
2071 | struct inode *inode; |
2072 | unsigned tid; | |
2073 | ||
99f89551 EB |
2074 | if (!leader) |
2075 | goto out_no_task; | |
2076 | ||
1da177e4 LT |
2077 | tid = name_to_int(dentry); |
2078 | if (tid == ~0U) | |
2079 | goto out; | |
2080 | ||
de758734 | 2081 | rcu_read_lock(); |
1da177e4 LT |
2082 | task = find_task_by_pid(tid); |
2083 | if (task) | |
2084 | get_task_struct(task); | |
de758734 | 2085 | rcu_read_unlock(); |
1da177e4 LT |
2086 | if (!task) |
2087 | goto out; | |
2088 | if (leader->tgid != task->tgid) | |
2089 | goto out_drop_task; | |
2090 | ||
2091 | inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO); | |
2092 | ||
2093 | ||
2094 | if (!inode) | |
2095 | goto out_drop_task; | |
2096 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2097 | inode->i_op = &proc_tid_base_inode_operations; | |
2098 | inode->i_fop = &proc_tid_base_operations; | |
1da177e4 | 2099 | inode->i_flags|=S_IMMUTABLE; |
bcf88e11 DD |
2100 | #ifdef CONFIG_SECURITY |
2101 | inode->i_nlink = 4; | |
2102 | #else | |
2103 | inode->i_nlink = 3; | |
2104 | #endif | |
1da177e4 | 2105 | |
48e6484d | 2106 | dentry->d_op = &pid_dentry_operations; |
1da177e4 LT |
2107 | |
2108 | d_add(dentry, inode); | |
cd6a3ce9 EB |
2109 | /* Close the race of the process dying before we return the dentry */ |
2110 | if (pid_revalidate(dentry, NULL)) | |
2111 | result = NULL; | |
1da177e4 | 2112 | |
1da177e4 LT |
2113 | out_drop_task: |
2114 | put_task_struct(task); | |
2115 | out: | |
99f89551 EB |
2116 | put_task_struct(leader); |
2117 | out_no_task: | |
cd6a3ce9 | 2118 | return result; |
1da177e4 LT |
2119 | } |
2120 | ||
1da177e4 | 2121 | /* |
0bc58a91 EB |
2122 | * Find the first tgid to return to user space. |
2123 | * | |
2124 | * Usually this is just whatever follows &init_task, but if the users | |
2125 | * buffer was too small to hold the full list or there was a seek into | |
2126 | * the middle of the directory we have more work to do. | |
2127 | * | |
2128 | * In the case of a short read we start with find_task_by_pid. | |
2129 | * | |
2130 | * In the case of a seek we start with &init_task and walk nr | |
2131 | * threads past it. | |
1da177e4 | 2132 | */ |
9cc8cbc7 | 2133 | static struct task_struct *first_tgid(int tgid, unsigned int nr) |
1da177e4 | 2134 | { |
9cc8cbc7 | 2135 | struct task_struct *pos; |
454cc105 | 2136 | rcu_read_lock(); |
0bc58a91 EB |
2137 | if (tgid && nr) { |
2138 | pos = find_task_by_pid(tgid); | |
9cc8cbc7 EB |
2139 | if (pos && thread_group_leader(pos)) |
2140 | goto found; | |
1da177e4 | 2141 | } |
0bc58a91 | 2142 | /* If nr exceeds the number of processes get out quickly */ |
9cc8cbc7 | 2143 | pos = NULL; |
0bc58a91 EB |
2144 | if (nr && nr >= nr_processes()) |
2145 | goto done; | |
1da177e4 | 2146 | |
0bc58a91 EB |
2147 | /* If we haven't found our starting place yet start with |
2148 | * the init_task and walk nr tasks forward. | |
2149 | */ | |
9cc8cbc7 EB |
2150 | for (pos = next_task(&init_task); nr > 0; --nr) { |
2151 | pos = next_task(pos); | |
2152 | if (pos == &init_task) { | |
2153 | pos = NULL; | |
2154 | goto done; | |
2155 | } | |
1da177e4 | 2156 | } |
9cc8cbc7 EB |
2157 | found: |
2158 | get_task_struct(pos); | |
0bc58a91 | 2159 | done: |
454cc105 | 2160 | rcu_read_unlock(); |
0bc58a91 | 2161 | return pos; |
1da177e4 LT |
2162 | } |
2163 | ||
2164 | /* | |
0bc58a91 EB |
2165 | * Find the next task in the task list. |
2166 | * Return NULL if we loop or there is any error. | |
2167 | * | |
2168 | * The reference to the input task_struct is released. | |
1da177e4 | 2169 | */ |
0bc58a91 | 2170 | static struct task_struct *next_tgid(struct task_struct *start) |
1da177e4 | 2171 | { |
0bc58a91 | 2172 | struct task_struct *pos; |
454cc105 | 2173 | rcu_read_lock(); |
0bc58a91 EB |
2174 | pos = start; |
2175 | if (pid_alive(start)) | |
2176 | pos = next_task(start); | |
2177 | if (pid_alive(pos) && (pos != &init_task)) { | |
2178 | get_task_struct(pos); | |
2179 | goto done; | |
2180 | } | |
2181 | pos = NULL; | |
2182 | done: | |
454cc105 | 2183 | rcu_read_unlock(); |
0bc58a91 EB |
2184 | put_task_struct(start); |
2185 | return pos; | |
1da177e4 LT |
2186 | } |
2187 | ||
2188 | /* for the /proc/ directory itself, after non-process stuff has been done */ | |
2189 | int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2190 | { | |
1da177e4 LT |
2191 | char buf[PROC_NUMBUF]; |
2192 | unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; | |
0bc58a91 EB |
2193 | struct task_struct *task; |
2194 | int tgid; | |
1da177e4 LT |
2195 | |
2196 | if (!nr) { | |
2197 | ino_t ino = fake_ino(0,PROC_TGID_INO); | |
2198 | if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0) | |
2199 | return 0; | |
2200 | filp->f_pos++; | |
2201 | nr++; | |
2202 | } | |
0bc58a91 | 2203 | nr -= 1; |
1da177e4 LT |
2204 | |
2205 | /* f_version caches the tgid value that the last readdir call couldn't | |
2206 | * return. lseek aka telldir automagically resets f_version to 0. | |
2207 | */ | |
0bc58a91 | 2208 | tgid = filp->f_version; |
1da177e4 | 2209 | filp->f_version = 0; |
0bc58a91 EB |
2210 | for (task = first_tgid(tgid, nr); |
2211 | task; | |
2212 | task = next_tgid(task), filp->f_pos++) { | |
2213 | int len; | |
2214 | ino_t ino; | |
2215 | tgid = task->pid; | |
2216 | len = snprintf(buf, sizeof(buf), "%d", tgid); | |
2217 | ino = fake_ino(tgid, PROC_TGID_INO); | |
2218 | if (filldir(dirent, buf, len, filp->f_pos, ino, DT_DIR) < 0) { | |
2219 | /* returning this tgid failed, save it as the first | |
2220 | * pid for the next readir call */ | |
2221 | filp->f_version = tgid; | |
2222 | put_task_struct(task); | |
1da177e4 LT |
2223 | break; |
2224 | } | |
0bc58a91 EB |
2225 | } |
2226 | return 0; | |
2227 | } | |
1da177e4 | 2228 | |
0bc58a91 EB |
2229 | /* |
2230 | * Find the first tid of a thread group to return to user space. | |
2231 | * | |
2232 | * Usually this is just the thread group leader, but if the users | |
2233 | * buffer was too small or there was a seek into the middle of the | |
2234 | * directory we have more work todo. | |
2235 | * | |
2236 | * In the case of a short read we start with find_task_by_pid. | |
2237 | * | |
2238 | * In the case of a seek we start with the leader and walk nr | |
2239 | * threads past it. | |
2240 | */ | |
2241 | static struct task_struct *first_tid(struct task_struct *leader, int tid, int nr) | |
2242 | { | |
2243 | struct task_struct *pos = NULL; | |
2244 | read_lock(&tasklist_lock); | |
1da177e4 | 2245 | |
0bc58a91 EB |
2246 | /* Attempt to start with the pid of a thread */ |
2247 | if (tid && (nr > 0)) { | |
2248 | pos = find_task_by_pid(tid); | |
2249 | if (pos && (pos->group_leader != leader)) | |
2250 | pos = NULL; | |
2251 | if (pos) | |
2252 | nr = 0; | |
2253 | } | |
1da177e4 | 2254 | |
0bc58a91 EB |
2255 | /* If nr exceeds the number of threads there is nothing todo */ |
2256 | if (nr) { | |
99f89551 | 2257 | if (nr >= get_nr_threads(leader)) |
0bc58a91 EB |
2258 | goto done; |
2259 | } | |
1da177e4 | 2260 | |
0bc58a91 EB |
2261 | /* If we haven't found our starting place yet start with the |
2262 | * leader and walk nr threads forward. | |
2263 | */ | |
2264 | if (!pos && (nr >= 0)) | |
2265 | pos = leader; | |
2266 | ||
2267 | for (; pos && pid_alive(pos); pos = next_thread(pos)) { | |
2268 | if (--nr > 0) | |
2269 | continue; | |
2270 | get_task_struct(pos); | |
2271 | goto done; | |
1da177e4 | 2272 | } |
0bc58a91 EB |
2273 | pos = NULL; |
2274 | done: | |
2275 | read_unlock(&tasklist_lock); | |
2276 | return pos; | |
2277 | } | |
2278 | ||
2279 | /* | |
2280 | * Find the next thread in the thread list. | |
2281 | * Return NULL if there is an error or no next thread. | |
2282 | * | |
2283 | * The reference to the input task_struct is released. | |
2284 | */ | |
2285 | static struct task_struct *next_tid(struct task_struct *start) | |
2286 | { | |
2287 | struct task_struct *pos; | |
2288 | read_lock(&tasklist_lock); | |
2289 | pos = start; | |
2290 | if (pid_alive(start)) | |
2291 | pos = next_thread(start); | |
2292 | if (pid_alive(pos) && (pos != start->group_leader)) | |
2293 | get_task_struct(pos); | |
2294 | else | |
2295 | pos = NULL; | |
2296 | read_unlock(&tasklist_lock); | |
2297 | put_task_struct(start); | |
2298 | return pos; | |
1da177e4 LT |
2299 | } |
2300 | ||
2301 | /* for the /proc/TGID/task/ directories */ | |
2302 | static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2303 | { | |
1da177e4 | 2304 | char buf[PROC_NUMBUF]; |
1da177e4 LT |
2305 | struct dentry *dentry = filp->f_dentry; |
2306 | struct inode *inode = dentry->d_inode; | |
99f89551 | 2307 | struct task_struct *leader = get_proc_task(inode); |
0bc58a91 | 2308 | struct task_struct *task; |
1da177e4 LT |
2309 | int retval = -ENOENT; |
2310 | ino_t ino; | |
0bc58a91 | 2311 | int tid; |
1da177e4 LT |
2312 | unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ |
2313 | ||
99f89551 EB |
2314 | if (!leader) |
2315 | goto out_no_task; | |
1da177e4 LT |
2316 | retval = 0; |
2317 | ||
2318 | switch (pos) { | |
2319 | case 0: | |
2320 | ino = inode->i_ino; | |
2321 | if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) | |
2322 | goto out; | |
2323 | pos++; | |
2324 | /* fall through */ | |
2325 | case 1: | |
2326 | ino = parent_ino(dentry); | |
2327 | if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) | |
2328 | goto out; | |
2329 | pos++; | |
2330 | /* fall through */ | |
2331 | } | |
2332 | ||
0bc58a91 EB |
2333 | /* f_version caches the tgid value that the last readdir call couldn't |
2334 | * return. lseek aka telldir automagically resets f_version to 0. | |
2335 | */ | |
2336 | tid = filp->f_version; | |
2337 | filp->f_version = 0; | |
2338 | for (task = first_tid(leader, tid, pos - 2); | |
2339 | task; | |
2340 | task = next_tid(task), pos++) { | |
2341 | int len; | |
2342 | tid = task->pid; | |
2343 | len = snprintf(buf, sizeof(buf), "%d", tid); | |
2344 | ino = fake_ino(tid, PROC_TID_INO); | |
2345 | if (filldir(dirent, buf, len, pos, ino, DT_DIR < 0)) { | |
2346 | /* returning this tgid failed, save it as the first | |
2347 | * pid for the next readir call */ | |
2348 | filp->f_version = tid; | |
2349 | put_task_struct(task); | |
1da177e4 | 2350 | break; |
0bc58a91 | 2351 | } |
1da177e4 LT |
2352 | } |
2353 | out: | |
2354 | filp->f_pos = pos; | |
99f89551 EB |
2355 | put_task_struct(leader); |
2356 | out_no_task: | |
1da177e4 LT |
2357 | return retval; |
2358 | } | |
6e66b52b EB |
2359 | |
2360 | static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
2361 | { | |
2362 | struct inode *inode = dentry->d_inode; | |
99f89551 | 2363 | struct task_struct *p = get_proc_task(inode); |
6e66b52b EB |
2364 | generic_fillattr(inode, stat); |
2365 | ||
99f89551 EB |
2366 | if (p) { |
2367 | rcu_read_lock(); | |
2368 | stat->nlink += get_nr_threads(p); | |
2369 | rcu_read_unlock(); | |
2370 | put_task_struct(p); | |
6e66b52b EB |
2371 | } |
2372 | ||
2373 | return 0; | |
2374 | } |