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[PATCH] allow callers of seq_open do allocation themselves
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / proc / base.c
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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>
58#include <linux/file.h>
59#include <linux/string.h>
60#include <linux/seq_file.h>
61#include <linux/namei.h>
62#include <linux/namespace.h>
63#include <linux/mm.h>
64#include <linux/smp_lock.h>
b835996f 65#include <linux/rcupdate.h>
1da177e4
LT		 66#include <linux/kallsyms.h>
67#include <linux/mount.h>
68#include <linux/security.h>
69#include <linux/ptrace.h>
70#include <linux/seccomp.h>
71#include <linux/cpuset.h>
72#include <linux/audit.h>
73#include "internal.h"
74
75/*
76 * For hysterical raisins we keep the same inumbers as in the old procfs.
77 * Feel free to change the macro below - just keep the range distinct from
78 * inumbers of the rest of procfs (currently those are in 0x0000--0xffff).
79 * As soon as we'll get a separate superblock we will be able to forget
80 * about magical ranges too.
81 */
82
83#define fake_ino(pid,ino) (((pid)<<16)|(ino))
84
85enum pid_directory_inos {
86 PROC_TGID_INO = 2,
87 PROC_TGID_TASK,
88 PROC_TGID_STATUS,
89 PROC_TGID_MEM,
90#ifdef CONFIG_SECCOMP
91 PROC_TGID_SECCOMP,
92#endif
93 PROC_TGID_CWD,
94 PROC_TGID_ROOT,
95 PROC_TGID_EXE,
96 PROC_TGID_FD,
97 PROC_TGID_ENVIRON,
98 PROC_TGID_AUXV,
99 PROC_TGID_CMDLINE,
100 PROC_TGID_STAT,
101 PROC_TGID_STATM,
102 PROC_TGID_MAPS,
6e21c8f1 103 PROC_TGID_NUMA_MAPS,
1da177e4
LT		 104 PROC_TGID_MOUNTS,
105 PROC_TGID_WCHAN,
63c6764c 106#ifdef CONFIG_MMU
e070ad49 107 PROC_TGID_SMAPS,
63c6764c 108#endif
1da177e4
LT		 109#ifdef CONFIG_SCHEDSTATS
110 PROC_TGID_SCHEDSTAT,
111#endif
112#ifdef CONFIG_CPUSETS
113 PROC_TGID_CPUSET,
114#endif
115#ifdef CONFIG_SECURITY
116 PROC_TGID_ATTR,
117 PROC_TGID_ATTR_CURRENT,
118 PROC_TGID_ATTR_PREV,
119 PROC_TGID_ATTR_EXEC,
120 PROC_TGID_ATTR_FSCREATE,
121#endif
122#ifdef CONFIG_AUDITSYSCALL
123 PROC_TGID_LOGINUID,
124#endif
1da177e4
LT		 125 PROC_TGID_OOM_SCORE,
126 PROC_TGID_OOM_ADJUST,
127 PROC_TID_INO,
128 PROC_TID_STATUS,
129 PROC_TID_MEM,
130#ifdef CONFIG_SECCOMP
131 PROC_TID_SECCOMP,
132#endif
133 PROC_TID_CWD,
134 PROC_TID_ROOT,
135 PROC_TID_EXE,
136 PROC_TID_FD,
137 PROC_TID_ENVIRON,
138 PROC_TID_AUXV,
139 PROC_TID_CMDLINE,
140 PROC_TID_STAT,
141 PROC_TID_STATM,
142 PROC_TID_MAPS,
6e21c8f1 143 PROC_TID_NUMA_MAPS,
1da177e4
LT		 144 PROC_TID_MOUNTS,
145 PROC_TID_WCHAN,
63c6764c 146#ifdef CONFIG_MMU
e070ad49 147 PROC_TID_SMAPS,
63c6764c 148#endif
1da177e4
LT		 149#ifdef CONFIG_SCHEDSTATS
150 PROC_TID_SCHEDSTAT,
151#endif
152#ifdef CONFIG_CPUSETS
153 PROC_TID_CPUSET,
154#endif
155#ifdef CONFIG_SECURITY
156 PROC_TID_ATTR,
157 PROC_TID_ATTR_CURRENT,
158 PROC_TID_ATTR_PREV,
159 PROC_TID_ATTR_EXEC,
160 PROC_TID_ATTR_FSCREATE,
161#endif
162#ifdef CONFIG_AUDITSYSCALL
163 PROC_TID_LOGINUID,
164#endif
1da177e4
LT		 165 PROC_TID_OOM_SCORE,
166 PROC_TID_OOM_ADJUST,
5e21ccb1
MS		 167
168 /* Add new entries before this */
169 PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */
1da177e4
LT		 170};
171
172struct pid_entry {
173 int type;
174 int len;
175 char *name;
176 mode_t mode;
177};
178
179#define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)}
180
181static struct pid_entry tgid_base_stuff[] = {
182 E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO),
183 E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR),
184 E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR),
185 E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR),
186 E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO),
187 E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
188 E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO),
189 E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO),
190 E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO),
6e21c8f1
CL		 191#ifdef CONFIG_NUMA
192 E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
193#endif
1da177e4
LT		 194 E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR),
195#ifdef CONFIG_SECCOMP
196 E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
197#endif
198 E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO),
199 E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO),
200 E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO),
201 E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
63c6764c 202#ifdef CONFIG_MMU
e070ad49 203 E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO),
63c6764c 204#endif
1da177e4
LT		 205#ifdef CONFIG_SECURITY
206 E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
207#endif
208#ifdef CONFIG_KALLSYMS
209 E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO),
210#endif
211#ifdef CONFIG_SCHEDSTATS
212 E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO),
213#endif
214#ifdef CONFIG_CPUSETS
215 E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO),
216#endif
217 E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO),
218 E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
219#ifdef CONFIG_AUDITSYSCALL
220 E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
221#endif
222 {0,0,NULL,0}
223};
224static struct pid_entry tid_base_stuff[] = {
225 E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR),
226 E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR),
227 E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR),
228 E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO),
229 E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
230 E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO),
231 E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO),
232 E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO),
6e21c8f1
CL		 233#ifdef CONFIG_NUMA
234 E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
235#endif
1da177e4
LT		 236 E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR),
237#ifdef CONFIG_SECCOMP
238 E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
239#endif
240 E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO),
241 E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO),
242 E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO),
243 E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
63c6764c 244#ifdef CONFIG_MMU
e070ad49 245 E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO),
63c6764c 246#endif
1da177e4
LT		 247#ifdef CONFIG_SECURITY
248 E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
249#endif
250#ifdef CONFIG_KALLSYMS
251 E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO),
252#endif
253#ifdef CONFIG_SCHEDSTATS
254 E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO),
255#endif
256#ifdef CONFIG_CPUSETS
257 E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO),
258#endif
259 E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO),
260 E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
261#ifdef CONFIG_AUDITSYSCALL
262 E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
263#endif
264 {0,0,NULL,0}
265};
266
267#ifdef CONFIG_SECURITY
268static struct pid_entry tgid_attr_stuff[] = {
269 E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO),
270 E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
271 E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
272 E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
273 {0,0,NULL,0}
274};
275static struct pid_entry tid_attr_stuff[] = {
276 E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO),
277 E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
278 E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
279 E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
280 {0,0,NULL,0}
281};
282#endif
283
284#undef E
285
286static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
287{
288 struct task_struct *task = proc_task(inode);
289 struct files_struct *files;
290 struct file *file;
291 int fd = proc_type(inode) - PROC_TID_FD_DIR;
292
293 files = get_files_struct(task);
294 if (files) {
b835996f 295 rcu_read_lock();
1da177e4
LT		 296 file = fcheck_files(files, fd);
297 if (file) {
298 *mnt = mntget(file->f_vfsmnt);
299 *dentry = dget(file->f_dentry);
b835996f 300 rcu_read_unlock();
1da177e4
LT		 301 put_files_struct(files);
302 return 0;
303 }
b835996f 304 rcu_read_unlock();
1da177e4
LT		 305 put_files_struct(files);
306 }
307 return -ENOENT;
308}
309
0494f6ec 310static struct fs_struct *get_fs_struct(struct task_struct *task)
1da177e4
LT		 311{
312 struct fs_struct *fs;
0494f6ec
MS		 313 task_lock(task);
314 fs = task->fs;
1da177e4
LT		 315 if(fs)
316 atomic_inc(&fs->count);
0494f6ec
MS		 317 task_unlock(task);
318 return fs;
319}
320
321static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
322{
323 struct fs_struct *fs = get_fs_struct(proc_task(inode));
324 int result = -ENOENT;
1da177e4
LT		 325 if (fs) {
326 read_lock(&fs->lock);
327 *mnt = mntget(fs->pwdmnt);
328 *dentry = dget(fs->pwd);
329 read_unlock(&fs->lock);
330 result = 0;
331 put_fs_struct(fs);
332 }
333 return result;
334}
335
336static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
337{
0494f6ec 338 struct fs_struct *fs = get_fs_struct(proc_task(inode));
1da177e4 339 int result = -ENOENT;
1da177e4
LT		 340 if (fs) {
341 read_lock(&fs->lock);
342 *mnt = mntget(fs->rootmnt);
343 *dentry = dget(fs->root);
344 read_unlock(&fs->lock);
345 result = 0;
346 put_fs_struct(fs);
347 }
348 return result;
349}
350
66dcca06
SK		 351
352/* Same as proc_root_link, but this addionally tries to get fs from other
353 * threads in the group */
0678e5fe
AM		 354static int proc_task_root_link(struct inode *inode, struct dentry **dentry,
355 struct vfsmount **mnt)
66dcca06
SK		 356{
357 struct fs_struct *fs;
358 int result = -ENOENT;
359 struct task_struct *leader = proc_task(inode);
360
361 task_lock(leader);
362 fs = leader->fs;
363 if (fs) {
364 atomic_inc(&fs->count);
365 task_unlock(leader);
366 } else {
367 /* Try to get fs from other threads */
368 task_unlock(leader);
66dcca06 369 read_lock(&tasklist_lock);
0678e5fe
AM		 370 if (pid_alive(leader)) {
371 struct task_struct *task = leader;
372
66dcca06
SK		 373 while ((task = next_thread(task)) != leader) {
374 task_lock(task);
375 fs = task->fs;
376 if (fs) {
377 atomic_inc(&fs->count);
378 task_unlock(task);
379 break;
380 }
381 task_unlock(task);
382 }
383 }
384 read_unlock(&tasklist_lock);
385 }
386
387 if (fs) {
388 read_lock(&fs->lock);
389 *mnt = mntget(fs->rootmnt);
390 *dentry = dget(fs->root);
391 read_unlock(&fs->lock);
392 result = 0;
393 put_fs_struct(fs);
394 }
395 return result;
396}
397
398
1da177e4
LT		 399#define MAY_PTRACE(task) \
400 (task == current || \
401 (task->parent == current && \
402 (task->ptrace & PT_PTRACED) && \
403 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
404 security_ptrace(current,task) == 0))
405
1da177e4
LT		 406static int proc_pid_environ(struct task_struct *task, char * buffer)
407{
408 int res = 0;
409 struct mm_struct *mm = get_task_mm(task);
410 if (mm) {
411 unsigned int len = mm->env_end - mm->env_start;
412 if (len > PAGE_SIZE)
413 len = PAGE_SIZE;
414 res = access_process_vm(task, mm->env_start, buffer, len, 0);
ab8d11be 415 if (!ptrace_may_attach(task))
1da177e4
LT		 416 res = -ESRCH;
417 mmput(mm);
418 }
419 return res;
420}
421
422static int proc_pid_cmdline(struct task_struct *task, char * buffer)
423{
424 int res = 0;
425 unsigned int len;
426 struct mm_struct *mm = get_task_mm(task);
427 if (!mm)
428 goto out;
429 if (!mm->arg_end)
430 goto out_mm; /* Shh! No looking before we're done */
431
432 len = mm->arg_end - mm->arg_start;
433
434 if (len > PAGE_SIZE)
435 len = PAGE_SIZE;
436
437 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
438
439 // If the nul at the end of args has been overwritten, then
440 // assume application is using setproctitle(3).
441 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
442 len = strnlen(buffer, res);
443 if (len < res) {
444 res = len;
445 } else {
446 len = mm->env_end - mm->env_start;
447 if (len > PAGE_SIZE - res)
448 len = PAGE_SIZE - res;
449 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
450 res = strnlen(buffer, res);
451 }
452 }
453out_mm:
454 mmput(mm);
455out:
456 return res;
457}
458
459static int proc_pid_auxv(struct task_struct *task, char *buffer)
460{
461 int res = 0;
462 struct mm_struct *mm = get_task_mm(task);
463 if (mm) {
464 unsigned int nwords = 0;
465 do
466 nwords += 2;
467 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
468 res = nwords * sizeof(mm->saved_auxv[0]);
469 if (res > PAGE_SIZE)
470 res = PAGE_SIZE;
471 memcpy(buffer, mm->saved_auxv, res);
472 mmput(mm);
473 }
474 return res;
475}
476
477
478#ifdef CONFIG_KALLSYMS
479/*
480 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
481 * Returns the resolved symbol. If that fails, simply return the address.
482 */
483static int proc_pid_wchan(struct task_struct *task, char *buffer)
484{
485 char *modname;
486 const char *sym_name;
487 unsigned long wchan, size, offset;
488 char namebuf[KSYM_NAME_LEN+1];
489
490 wchan = get_wchan(task);
491
492 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf);
493 if (sym_name)
494 return sprintf(buffer, "%s", sym_name);
495 return sprintf(buffer, "%lu", wchan);
496}
497#endif /* CONFIG_KALLSYMS */
498
499#ifdef CONFIG_SCHEDSTATS
500/*
501 * Provides /proc/PID/schedstat
502 */
503static int proc_pid_schedstat(struct task_struct *task, char *buffer)
504{
505 return sprintf(buffer, "%lu %lu %lu\n",
506 task->sched_info.cpu_time,
507 task->sched_info.run_delay,
508 task->sched_info.pcnt);
509}
510#endif
511
512/* The badness from the OOM killer */
513unsigned long badness(struct task_struct *p, unsigned long uptime);
514static int proc_oom_score(struct task_struct *task, char *buffer)
515{
516 unsigned long points;
517 struct timespec uptime;
518
519 do_posix_clock_monotonic_gettime(&uptime);
520 points = badness(task, uptime.tv_sec);
521 return sprintf(buffer, "%lu\n", points);
522}
523
524/************************************************************************/
525/* Here the fs part begins */
526/************************************************************************/
527
528/* permission checks */
529
66dcca06
SK		 530/* If the process being read is separated by chroot from the reading process,
531 * don't let the reader access the threads.
532 */
533static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt)
1da177e4 534{
66dcca06
SK		 535 struct dentry *de, *base;
536 struct vfsmount *our_vfsmnt, *mnt;
1da177e4 537 int res = 0;
1da177e4
LT		 538 read_lock(&current->fs->lock);
539 our_vfsmnt = mntget(current->fs->rootmnt);
540 base = dget(current->fs->root);
541 read_unlock(&current->fs->lock);
542
543 spin_lock(&vfsmount_lock);
544 de = root;
545 mnt = vfsmnt;
546
547 while (vfsmnt != our_vfsmnt) {
548 if (vfsmnt == vfsmnt->mnt_parent)
549 goto out;
550 de = vfsmnt->mnt_mountpoint;
551 vfsmnt = vfsmnt->mnt_parent;
552 }
553
554 if (!is_subdir(de, base))
555 goto out;
556 spin_unlock(&vfsmount_lock);
557
558exit:
559 dput(base);
560 mntput(our_vfsmnt);
561 dput(root);
562 mntput(mnt);
563 return res;
564out:
565 spin_unlock(&vfsmount_lock);
566 res = -EACCES;
567 goto exit;
568}
569
66dcca06
SK		 570static int proc_check_root(struct inode *inode)
571{
572 struct dentry *root;
573 struct vfsmount *vfsmnt;
574
575 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */
576 return -ENOENT;
577 return proc_check_chroot(root, vfsmnt);
578}
579
1da177e4
LT		 580static int proc_permission(struct inode *inode, int mask, struct nameidata *nd)
581{
582 if (generic_permission(inode, mask, NULL) != 0)
583 return -EACCES;
584 return proc_check_root(inode);
585}
586
66dcca06
SK		 587static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd)
588{
589 struct dentry *root;
590 struct vfsmount *vfsmnt;
591
592 if (generic_permission(inode, mask, NULL) != 0)
593 return -EACCES;
594
595 if (proc_task_root_link(inode, &root, &vfsmnt))
596 return -ENOENT;
597
598 return proc_check_chroot(root, vfsmnt);
599}
600
1da177e4
LT		 601extern struct seq_operations proc_pid_maps_op;
602static int maps_open(struct inode *inode, struct file *file)
603{
604 struct task_struct *task = proc_task(inode);
605 int ret = seq_open(file, &proc_pid_maps_op);
606 if (!ret) {
607 struct seq_file *m = file->private_data;
608 m->private = task;
609 }
610 return ret;
611}
612
613static struct file_operations proc_maps_operations = {
614 .open = maps_open,
615 .read = seq_read,
616 .llseek = seq_lseek,
617 .release = seq_release,
618};
619
6e21c8f1
CL		 620#ifdef CONFIG_NUMA
621extern struct seq_operations proc_pid_numa_maps_op;
622static int numa_maps_open(struct inode *inode, struct file *file)
623{
624 struct task_struct *task = proc_task(inode);
625 int ret = seq_open(file, &proc_pid_numa_maps_op);
626 if (!ret) {
627 struct seq_file *m = file->private_data;
628 m->private = task;
629 }
630 return ret;
631}
632
633static struct file_operations proc_numa_maps_operations = {
634 .open = numa_maps_open,
635 .read = seq_read,
636 .llseek = seq_lseek,
637 .release = seq_release,
638};
639#endif
640
63c6764c 641#ifdef CONFIG_MMU
e070ad49
ML		 642extern struct seq_operations proc_pid_smaps_op;
643static int smaps_open(struct inode *inode, struct file *file)
644{
645 struct task_struct *task = proc_task(inode);
646 int ret = seq_open(file, &proc_pid_smaps_op);
647 if (!ret) {
648 struct seq_file *m = file->private_data;
649 m->private = task;
650 }
651 return ret;
652}
653
654static struct file_operations proc_smaps_operations = {
655 .open = smaps_open,
656 .read = seq_read,
657 .llseek = seq_lseek,
658 .release = seq_release,
659};
63c6764c 660#endif
e070ad49 661
1da177e4
LT		 662extern struct seq_operations mounts_op;
663static int mounts_open(struct inode *inode, struct file *file)
664{
665 struct task_struct *task = proc_task(inode);
666 int ret = seq_open(file, &mounts_op);
667
668 if (!ret) {
669 struct seq_file *m = file->private_data;
670 struct namespace *namespace;
671 task_lock(task);
672 namespace = task->namespace;
673 if (namespace)
674 get_namespace(namespace);
675 task_unlock(task);
676
677 if (namespace)
678 m->private = namespace;
679 else {
680 seq_release(inode, file);
681 ret = -EINVAL;
682 }
683 }
684 return ret;
685}
686
687static int mounts_release(struct inode *inode, struct file *file)
688{
689 struct seq_file *m = file->private_data;
690 struct namespace *namespace = m->private;
691 put_namespace(namespace);
692 return seq_release(inode, file);
693}
694
695static struct file_operations proc_mounts_operations = {
696 .open = mounts_open,
697 .read = seq_read,
698 .llseek = seq_lseek,
699 .release = mounts_release,
700};
701
702#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
703
704static ssize_t proc_info_read(struct file * file, char __user * buf,
705 size_t count, loff_t *ppos)
706{
707 struct inode * inode = file->f_dentry->d_inode;
708 unsigned long page;
709 ssize_t length;
710 struct task_struct *task = proc_task(inode);
711
712 if (count > PROC_BLOCK_SIZE)
713 count = PROC_BLOCK_SIZE;
714 if (!(page = __get_free_page(GFP_KERNEL)))
715 return -ENOMEM;
716
717 length = PROC_I(inode)->op.proc_read(task, (char*)page);
718
719 if (length >= 0)
720 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
721 free_page(page);
722 return length;
723}
724
725static struct file_operations proc_info_file_operations = {
726 .read = proc_info_read,
727};
728
729static int mem_open(struct inode* inode, struct file* file)
730{
731 file->private_data = (void*)((long)current->self_exec_id);
732 return 0;
733}
734
735static ssize_t mem_read(struct file * file, char __user * buf,
736 size_t count, loff_t *ppos)
737{
738 struct task_struct *task = proc_task(file->f_dentry->d_inode);
739 char *page;
740 unsigned long src = *ppos;
741 int ret = -ESRCH;
742 struct mm_struct *mm;
743
ab8d11be 744 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
1da177e4
LT		 745 goto out;
746
747 ret = -ENOMEM;
748 page = (char *)__get_free_page(GFP_USER);
749 if (!page)
750 goto out;
751
752 ret = 0;
753
754 mm = get_task_mm(task);
755 if (!mm)
756 goto out_free;
757
758 ret = -EIO;
759
760 if (file->private_data != (void*)((long)current->self_exec_id))
761 goto out_put;
762
763 ret = 0;
764
765 while (count > 0) {
766 int this_len, retval;
767
768 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
769 retval = access_process_vm(task, src, page, this_len, 0);
ab8d11be 770 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
1da177e4
LT		 771 if (!ret)
772 ret = -EIO;
773 break;
774 }
775
776 if (copy_to_user(buf, page, retval)) {
777 ret = -EFAULT;
778 break;
779 }
780
781 ret += retval;
782 src += retval;
783 buf += retval;
784 count -= retval;
785 }
786 *ppos = src;
787
788out_put:
789 mmput(mm);
790out_free:
791 free_page((unsigned long) page);
792out:
793 return ret;
794}
795
796#define mem_write NULL
797
798#ifndef mem_write
799/* This is a security hazard */
800static ssize_t mem_write(struct file * file, const char * buf,
801 size_t count, loff_t *ppos)
802{
803 int copied = 0;
804 char *page;
805 struct task_struct *task = proc_task(file->f_dentry->d_inode);
806 unsigned long dst = *ppos;
807
ab8d11be 808 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
1da177e4
LT		 809 return -ESRCH;
810
811 page = (char *)__get_free_page(GFP_USER);
812 if (!page)
813 return -ENOMEM;
814
815 while (count > 0) {
816 int this_len, retval;
817
818 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
819 if (copy_from_user(page, buf, this_len)) {
820 copied = -EFAULT;
821 break;
822 }
823 retval = access_process_vm(task, dst, page, this_len, 1);
824 if (!retval) {
825 if (!copied)
826 copied = -EIO;
827 break;
828 }
829 copied += retval;
830 buf += retval;
831 dst += retval;
832 count -= retval;
833 }
834 *ppos = dst;
835 free_page((unsigned long) page);
836 return copied;
837}
838#endif
839
840static loff_t mem_lseek(struct file * file, loff_t offset, int orig)
841{
842 switch (orig) {
843 case 0:
844 file->f_pos = offset;
845 break;
846 case 1:
847 file->f_pos += offset;
848 break;
849 default:
850 return -EINVAL;
851 }
852 force_successful_syscall_return();
853 return file->f_pos;
854}
855
856static struct file_operations proc_mem_operations = {
857 .llseek = mem_lseek,
858 .read = mem_read,
859 .write = mem_write,
860 .open = mem_open,
861};
862
863static ssize_t oom_adjust_read(struct file *file, char __user *buf,
864 size_t count, loff_t *ppos)
865{
866 struct task_struct *task = proc_task(file->f_dentry->d_inode);
867 char buffer[8];
868 size_t len;
869 int oom_adjust = task->oomkilladj;
870 loff_t __ppos = *ppos;
871
872 len = sprintf(buffer, "%i\n", oom_adjust);
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
883static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
884 size_t count, loff_t *ppos)
885{
886 struct task_struct *task = proc_task(file->f_dentry->d_inode);
887 char buffer[8], *end;
888 int oom_adjust;
889
890 if (!capable(CAP_SYS_RESOURCE))
891 return -EPERM;
892 memset(buffer, 0, 8);
893 if (count > 6)
894 count = 6;
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++;
902 task->oomkilladj = oom_adjust;
903 if (end - buffer == 0)
904 return -EIO;
905 return end - buffer;
906}
907
908static struct file_operations proc_oom_adjust_operations = {
909 .read = oom_adjust_read,
910 .write = oom_adjust_write,
911};
912
913static struct inode_operations proc_mem_inode_operations = {
914 .permission = proc_permission,
915};
916
917#ifdef CONFIG_AUDITSYSCALL
918#define TMPBUFLEN 21
919static 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;
923 struct task_struct *task = proc_task(inode);
924 ssize_t length;
925 char tmpbuf[TMPBUFLEN];
926
927 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
928 audit_get_loginuid(task->audit_context));
929 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
930}
931
932static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
933 size_t count, loff_t *ppos)
934{
935 struct inode * inode = file->f_dentry->d_inode;
936 char *page, *tmp;
937 ssize_t length;
938 struct task_struct *task = proc_task(inode);
939 uid_t loginuid;
940
941 if (!capable(CAP_AUDIT_CONTROL))
942 return -EPERM;
943
944 if (current != task)
945 return -EPERM;
946
947 if (count > PAGE_SIZE)
948 count = PAGE_SIZE;
949
950 if (*ppos != 0) {
951 /* No partial writes. */
952 return -EINVAL;
953 }
954 page = (char*)__get_free_page(GFP_USER);
955 if (!page)
956 return -ENOMEM;
957 length = -EFAULT;
958 if (copy_from_user(page, buf, count))
959 goto out_free_page;
960
961 loginuid = simple_strtoul(page, &tmp, 10);
962 if (tmp == page) {
963 length = -EINVAL;
964 goto out_free_page;
965
966 }
456be6cd 967 length = audit_set_loginuid(task, loginuid);
1da177e4
LT		 968 if (likely(length == 0))
969 length = count;
970
971out_free_page:
972 free_page((unsigned long) page);
973 return length;
974}
975
976static struct file_operations proc_loginuid_operations = {
977 .read = proc_loginuid_read,
978 .write = proc_loginuid_write,
979};
980#endif
981
982#ifdef CONFIG_SECCOMP
983static ssize_t seccomp_read(struct file *file, char __user *buf,
984 size_t count, loff_t *ppos)
985{
986 struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
987 char __buf[20];
988 loff_t __ppos = *ppos;
989 size_t len;
990
991 /* no need to print the trailing zero, so use only len */
992 len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
993 if (__ppos >= len)
994 return 0;
995 if (count > len - __ppos)
996 count = len - __ppos;
997 if (copy_to_user(buf, __buf + __ppos, count))
998 return -EFAULT;
999 *ppos = __ppos + count;
1000 return count;
1001}
1002
1003static ssize_t seccomp_write(struct file *file, const char __user *buf,
1004 size_t count, loff_t *ppos)
1005{
1006 struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
1007 char __buf[20], *end;
1008 unsigned int seccomp_mode;
1009
1010 /* can set it only once to be even more secure */
1011 if (unlikely(tsk->seccomp.mode))
1012 return -EPERM;
1013
1014 memset(__buf, 0, sizeof(__buf));
1015 count = min(count, sizeof(__buf) - 1);
1016 if (copy_from_user(__buf, buf, count))
1017 return -EFAULT;
1018 seccomp_mode = simple_strtoul(__buf, &end, 0);
1019 if (*end == '\n')
1020 end++;
1021 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) {
1022 tsk->seccomp.mode = seccomp_mode;
1023 set_tsk_thread_flag(tsk, TIF_SECCOMP);
1024 } else
1025 return -EINVAL;
1026 if (unlikely(!(end - __buf)))
1027 return -EIO;
1028 return end - __buf;
1029}
1030
1031static struct file_operations proc_seccomp_operations = {
1032 .read = seccomp_read,
1033 .write = seccomp_write,
1034};
1035#endif /* CONFIG_SECCOMP */
1036
008b150a 1037static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1038{
1039 struct inode *inode = dentry->d_inode;
1040 int error = -EACCES;
1041
1042 /* We don't need a base pointer in the /proc filesystem */
1043 path_release(nd);
1044
1045 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
1046 goto out;
1047 error = proc_check_root(inode);
1048 if (error)
1049 goto out;
1050
1051 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
1052 nd->last_type = LAST_BIND;
1053out:
008b150a 1054 return ERR_PTR(error);
1da177e4
LT		 1055}
1056
1057static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
1058 char __user *buffer, int buflen)
1059{
1060 struct inode * inode;
1061 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path;
1062 int len;
1063
1064 if (!tmp)
1065 return -ENOMEM;
1066
1067 inode = dentry->d_inode;
1068 path = d_path(dentry, mnt, tmp, PAGE_SIZE);
1069 len = PTR_ERR(path);
1070 if (IS_ERR(path))
1071 goto out;
1072 len = tmp + PAGE_SIZE - 1 - path;
1073
1074 if (len > buflen)
1075 len = buflen;
1076 if (copy_to_user(buffer, path, len))
1077 len = -EFAULT;
1078 out:
1079 free_page((unsigned long)tmp);
1080 return len;
1081}
1082
1083static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1084{
1085 int error = -EACCES;
1086 struct inode *inode = dentry->d_inode;
1087 struct dentry *de;
1088 struct vfsmount *mnt = NULL;
1089
1090 lock_kernel();
1091
1092 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
1093 goto out;
1094 error = proc_check_root(inode);
1095 if (error)
1096 goto out;
1097
1098 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
1099 if (error)
1100 goto out;
1101
1102 error = do_proc_readlink(de, mnt, buffer, buflen);
1103 dput(de);
1104 mntput(mnt);
1105out:
1106 unlock_kernel();
1107 return error;
1108}
1109
1110static struct inode_operations proc_pid_link_inode_operations = {
1111 .readlink = proc_pid_readlink,
1112 .follow_link = proc_pid_follow_link
1113};
1114
1115#define NUMBUF 10
1116
1117static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
1118{
1119 struct inode *inode = filp->f_dentry->d_inode;
1120 struct task_struct *p = proc_task(inode);
1121 unsigned int fd, tid, ino;
1122 int retval;
1123 char buf[NUMBUF];
1124 struct files_struct * files;
badf1662 1125 struct fdtable *fdt;
1da177e4
LT		 1126
1127 retval = -ENOENT;
1128 if (!pid_alive(p))
1129 goto out;
1130 retval = 0;
1131 tid = p->pid;
1132
1133 fd = filp->f_pos;
1134 switch (fd) {
1135 case 0:
1136 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1137 goto out;
1138 filp->f_pos++;
1139 case 1:
1140 ino = fake_ino(tid, PROC_TID_INO);
1141 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1142 goto out;
1143 filp->f_pos++;
1144 default:
1145 files = get_files_struct(p);
1146 if (!files)
1147 goto out;
b835996f 1148 rcu_read_lock();
badf1662 1149 fdt = files_fdtable(files);
1da177e4 1150 for (fd = filp->f_pos-2;
badf1662 1151 fd < fdt->max_fds;
1da177e4
LT		 1152 fd++, filp->f_pos++) {
1153 unsigned int i,j;
1154
1155 if (!fcheck_files(files, fd))
1156 continue;
b835996f 1157 rcu_read_unlock();
1da177e4
LT		 1158
1159 j = NUMBUF;
1160 i = fd;
1161 do {
1162 j--;
1163 buf[j] = '0' + (i % 10);
1164 i /= 10;
1165 } while (i);
1166
1167 ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
1168 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
b835996f 1169 rcu_read_lock();
1da177e4
LT		 1170 break;
1171 }
b835996f 1172 rcu_read_lock();
1da177e4 1173 }
b835996f 1174 rcu_read_unlock();
1da177e4
LT		 1175 put_files_struct(files);
1176 }
1177out:
1178 return retval;
1179}
1180
1181static int proc_pident_readdir(struct file *filp,
1182 void *dirent, filldir_t filldir,
1183 struct pid_entry *ents, unsigned int nents)
1184{
1185 int i;
1186 int pid;
1187 struct dentry *dentry = filp->f_dentry;
1188 struct inode *inode = dentry->d_inode;
1189 struct pid_entry *p;
1190 ino_t ino;
1191 int ret;
1192
1193 ret = -ENOENT;
1194 if (!pid_alive(proc_task(inode)))
1195 goto out;
1196
1197 ret = 0;
1198 pid = proc_task(inode)->pid;
1199 i = filp->f_pos;
1200 switch (i) {
1201 case 0:
1202 ino = inode->i_ino;
1203 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
1204 goto out;
1205 i++;
1206 filp->f_pos++;
1207 /* fall through */
1208 case 1:
1209 ino = parent_ino(dentry);
1210 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
1211 goto out;
1212 i++;
1213 filp->f_pos++;
1214 /* fall through */
1215 default:
1216 i -= 2;
1217 if (i >= nents) {
1218 ret = 1;
1219 goto out;
1220 }
1221 p = ents + i;
1222 while (p->name) {
1223 if (filldir(dirent, p->name, p->len, filp->f_pos,
1224 fake_ino(pid, p->type), p->mode >> 12) < 0)
1225 goto out;
1226 filp->f_pos++;
1227 p++;
1228 }
1229 }
1230
1231 ret = 1;
1232out:
1233 return ret;
1234}
1235
1236static int proc_tgid_base_readdir(struct file * filp,
1237 void * dirent, filldir_t filldir)
1238{
1239 return proc_pident_readdir(filp,dirent,filldir,
1240 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1241}
1242
1243static int proc_tid_base_readdir(struct file * filp,
1244 void * dirent, filldir_t filldir)
1245{
1246 return proc_pident_readdir(filp,dirent,filldir,
1247 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
1248}
1249
1250/* building an inode */
1251
1252static int task_dumpable(struct task_struct *task)
1253{
1254 int dumpable = 0;
1255 struct mm_struct *mm;
1256
1257 task_lock(task);
1258 mm = task->mm;
1259 if (mm)
1260 dumpable = mm->dumpable;
1261 task_unlock(task);
d6e71144
AC		 1262 if(dumpable == 1)
1263 return 1;
1264 return 0;
1da177e4
LT		 1265}
1266
1267
1268static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino)
1269{
1270 struct inode * inode;
1271 struct proc_inode *ei;
1272
1273 /* We need a new inode */
1274
1275 inode = new_inode(sb);
1276 if (!inode)
1277 goto out;
1278
1279 /* Common stuff */
1280 ei = PROC_I(inode);
1281 ei->task = NULL;
1282 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1283 inode->i_ino = fake_ino(task->pid, ino);
1284
1285 if (!pid_alive(task))
1286 goto out_unlock;
1287
1288 /*
1289 * grab the reference to task.
1290 */
1291 get_task_struct(task);
1292 ei->task = task;
1293 ei->type = ino;
1294 inode->i_uid = 0;
1295 inode->i_gid = 0;
1296 if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) {
1297 inode->i_uid = task->euid;
1298 inode->i_gid = task->egid;
1299 }
1300 security_task_to_inode(task, inode);
1301
1302out:
1303 return inode;
1304
1305out_unlock:
1306 ei->pde = NULL;
1307 iput(inode);
1308 return NULL;
1309}
1310
1311/* dentry stuff */
1312
1313/*
1314 * Exceptional case: normally we are not allowed to unhash a busy
1315 * directory. In this case, however, we can do it - no aliasing problems
1316 * due to the way we treat inodes.
1317 *
1318 * Rewrite the inode's ownerships here because the owning task may have
1319 * performed a setuid(), etc.
1320 */
1321static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1322{
1323 struct inode *inode = dentry->d_inode;
1324 struct task_struct *task = proc_task(inode);
1325 if (pid_alive(task)) {
1326 if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) {
1327 inode->i_uid = task->euid;
1328 inode->i_gid = task->egid;
1329 } else {
1330 inode->i_uid = 0;
1331 inode->i_gid = 0;
1332 }
1333 security_task_to_inode(task, inode);
1334 return 1;
1335 }
1336 d_drop(dentry);
1337 return 0;
1338}
1339
1340static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1341{
1342 struct inode *inode = dentry->d_inode;
1343 struct task_struct *task = proc_task(inode);
1344 int fd = proc_type(inode) - PROC_TID_FD_DIR;
1345 struct files_struct *files;
1346
1347 files = get_files_struct(task);
1348 if (files) {
b835996f 1349 rcu_read_lock();
1da177e4 1350 if (fcheck_files(files, fd)) {
b835996f 1351 rcu_read_unlock();
1da177e4
LT		 1352 put_files_struct(files);
1353 if (task_dumpable(task)) {
1354 inode->i_uid = task->euid;
1355 inode->i_gid = task->egid;
1356 } else {
1357 inode->i_uid = 0;
1358 inode->i_gid = 0;
1359 }
1360 security_task_to_inode(task, inode);
1361 return 1;
1362 }
b835996f 1363 rcu_read_unlock();
1da177e4
LT		 1364 put_files_struct(files);
1365 }
1366 d_drop(dentry);
1367 return 0;
1368}
1369
1370static void pid_base_iput(struct dentry *dentry, struct inode *inode)
1371{
1372 struct task_struct *task = proc_task(inode);
1373 spin_lock(&task->proc_lock);
1374 if (task->proc_dentry == dentry)
1375 task->proc_dentry = NULL;
1376 spin_unlock(&task->proc_lock);
1377 iput(inode);
1378}
1379
1380static int pid_delete_dentry(struct dentry * dentry)
1381{
1382 /* Is the task we represent dead?
1383 * If so, then don't put the dentry on the lru list,
1384 * kill it immediately.
1385 */
1386 return !pid_alive(proc_task(dentry->d_inode));
1387}
1388
1389static struct dentry_operations tid_fd_dentry_operations =
1390{
1391 .d_revalidate = tid_fd_revalidate,
1392 .d_delete = pid_delete_dentry,
1393};
1394
1395static struct dentry_operations pid_dentry_operations =
1396{
1397 .d_revalidate = pid_revalidate,
1398 .d_delete = pid_delete_dentry,
1399};
1400
1401static struct dentry_operations pid_base_dentry_operations =
1402{
1403 .d_revalidate = pid_revalidate,
1404 .d_iput = pid_base_iput,
1405 .d_delete = pid_delete_dentry,
1406};
1407
1408/* Lookups */
1409
1410static unsigned name_to_int(struct dentry *dentry)
1411{
1412 const char *name = dentry->d_name.name;
1413 int len = dentry->d_name.len;
1414 unsigned n = 0;
1415
1416 if (len > 1 && *name == '0')
1417 goto out;
1418 while (len-- > 0) {
1419 unsigned c = *name++ - '0';
1420 if (c > 9)
1421 goto out;
1422 if (n >= (~0U-9)/10)
1423 goto out;
1424 n *= 10;
1425 n += c;
1426 }
1427 return n;
1428out:
1429 return ~0U;
1430}
1431
1432/* SMP-safe */
1433static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
1434{
1435 struct task_struct *task = proc_task(dir);
1436 unsigned fd = name_to_int(dentry);
1437 struct file * file;
1438 struct files_struct * files;
1439 struct inode *inode;
1440 struct proc_inode *ei;
1441
1442 if (fd == ~0U)
1443 goto out;
1444 if (!pid_alive(task))
1445 goto out;
1446
1447 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);
1448 if (!inode)
1449 goto out;
1450 ei = PROC_I(inode);
1451 files = get_files_struct(task);
1452 if (!files)
1453 goto out_unlock;
1454 inode->i_mode = S_IFLNK;
b835996f 1455 rcu_read_lock();
1da177e4
LT		 1456 file = fcheck_files(files, fd);
1457 if (!file)
1458 goto out_unlock2;
1459 if (file->f_mode & 1)
1460 inode->i_mode |= S_IRUSR | S_IXUSR;
1461 if (file->f_mode & 2)
1462 inode->i_mode |= S_IWUSR | S_IXUSR;
b835996f 1463 rcu_read_unlock();
1da177e4
LT		 1464 put_files_struct(files);
1465 inode->i_op = &proc_pid_link_inode_operations;
1466 inode->i_size = 64;
1467 ei->op.proc_get_link = proc_fd_link;
1468 dentry->d_op = &tid_fd_dentry_operations;
1469 d_add(dentry, inode);
1470 return NULL;
1471
1472out_unlock2:
b835996f 1473 rcu_read_unlock();
1da177e4
LT		 1474 put_files_struct(files);
1475out_unlock:
1476 iput(inode);
1477out:
1478 return ERR_PTR(-ENOENT);
1479}
1480
1481static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir);
1482static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd);
1483
1484static struct file_operations proc_fd_operations = {
1485 .read = generic_read_dir,
1486 .readdir = proc_readfd,
1487};
1488
1489static struct file_operations proc_task_operations = {
1490 .read = generic_read_dir,
1491 .readdir = proc_task_readdir,
1492};
1493
1494/*
1495 * proc directories can do almost nothing..
1496 */
1497static struct inode_operations proc_fd_inode_operations = {
1498 .lookup = proc_lookupfd,
1499 .permission = proc_permission,
1500};
1501
1502static struct inode_operations proc_task_inode_operations = {
1503 .lookup = proc_task_lookup,
66dcca06 1504 .permission = proc_task_permission,
1da177e4
LT		 1505};
1506
1507#ifdef CONFIG_SECURITY
1508static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
1509 size_t count, loff_t *ppos)
1510{
1511 struct inode * inode = file->f_dentry->d_inode;
1512 unsigned long page;
1513 ssize_t length;
1514 struct task_struct *task = proc_task(inode);
1515
1516 if (count > PAGE_SIZE)
1517 count = PAGE_SIZE;
1518 if (!(page = __get_free_page(GFP_KERNEL)))
1519 return -ENOMEM;
1520
1521 length = security_getprocattr(task,
1522 (char*)file->f_dentry->d_name.name,
1523 (void*)page, count);
1524 if (length >= 0)
1525 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
1526 free_page(page);
1527 return length;
1528}
1529
1530static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
1531 size_t count, loff_t *ppos)
1532{
1533 struct inode * inode = file->f_dentry->d_inode;
1534 char *page;
1535 ssize_t length;
1536 struct task_struct *task = proc_task(inode);
1537
1538 if (count > PAGE_SIZE)
1539 count = PAGE_SIZE;
1540 if (*ppos != 0) {
1541 /* No partial writes. */
1542 return -EINVAL;
1543 }
1544 page = (char*)__get_free_page(GFP_USER);
1545 if (!page)
1546 return -ENOMEM;
1547 length = -EFAULT;
1548 if (copy_from_user(page, buf, count))
1549 goto out;
1550
1551 length = security_setprocattr(task,
1552 (char*)file->f_dentry->d_name.name,
1553 (void*)page, count);
1554out:
1555 free_page((unsigned long) page);
1556 return length;
1557}
1558
1559static struct file_operations proc_pid_attr_operations = {
1560 .read = proc_pid_attr_read,
1561 .write = proc_pid_attr_write,
1562};
1563
1564static struct file_operations proc_tid_attr_operations;
1565static struct inode_operations proc_tid_attr_inode_operations;
1566static struct file_operations proc_tgid_attr_operations;
1567static struct inode_operations proc_tgid_attr_inode_operations;
1568#endif
1569
f246315e
DD		 1570static int get_tid_list(int index, unsigned int *tids, struct inode *dir);
1571
1da177e4
LT		 1572/* SMP-safe */
1573static struct dentry *proc_pident_lookup(struct inode *dir,
1574 struct dentry *dentry,
1575 struct pid_entry *ents)
1576{
1577 struct inode *inode;
1578 int error;
1579 struct task_struct *task = proc_task(dir);
1580 struct pid_entry *p;
1581 struct proc_inode *ei;
1582
1583 error = -ENOENT;
1584 inode = NULL;
1585
1586 if (!pid_alive(task))
1587 goto out;
1588
1589 for (p = ents; p->name; p++) {
1590 if (p->len != dentry->d_name.len)
1591 continue;
1592 if (!memcmp(dentry->d_name.name, p->name, p->len))
1593 break;
1594 }
1595 if (!p->name)
1596 goto out;
1597
1598 error = -EINVAL;
1599 inode = proc_pid_make_inode(dir->i_sb, task, p->type);
1600 if (!inode)
1601 goto out;
1602
1603 ei = PROC_I(inode);
1604 inode->i_mode = p->mode;
1605 /*
1606 * Yes, it does not scale. And it should not. Don't add
1607 * new entries into /proc/<tgid>/ without very good reasons.
1608 */
1609 switch(p->type) {
1610 case PROC_TGID_TASK:
f246315e 1611 inode->i_nlink = 2 + get_tid_list(2, NULL, dir);
1da177e4
LT		 1612 inode->i_op = &proc_task_inode_operations;
1613 inode->i_fop = &proc_task_operations;
1614 break;
1615 case PROC_TID_FD:
1616 case PROC_TGID_FD:
1617 inode->i_nlink = 2;
1618 inode->i_op = &proc_fd_inode_operations;
1619 inode->i_fop = &proc_fd_operations;
1620 break;
1621 case PROC_TID_EXE:
1622 case PROC_TGID_EXE:
1623 inode->i_op = &proc_pid_link_inode_operations;
1624 ei->op.proc_get_link = proc_exe_link;
1625 break;
1626 case PROC_TID_CWD:
1627 case PROC_TGID_CWD:
1628 inode->i_op = &proc_pid_link_inode_operations;
1629 ei->op.proc_get_link = proc_cwd_link;
1630 break;
1631 case PROC_TID_ROOT:
1632 case PROC_TGID_ROOT:
1633 inode->i_op = &proc_pid_link_inode_operations;
1634 ei->op.proc_get_link = proc_root_link;
1635 break;
1636 case PROC_TID_ENVIRON:
1637 case PROC_TGID_ENVIRON:
1638 inode->i_fop = &proc_info_file_operations;
1639 ei->op.proc_read = proc_pid_environ;
1640 break;
1641 case PROC_TID_AUXV:
1642 case PROC_TGID_AUXV:
1643 inode->i_fop = &proc_info_file_operations;
1644 ei->op.proc_read = proc_pid_auxv;
1645 break;
1646 case PROC_TID_STATUS:
1647 case PROC_TGID_STATUS:
1648 inode->i_fop = &proc_info_file_operations;
1649 ei->op.proc_read = proc_pid_status;
1650 break;
1651 case PROC_TID_STAT:
1652 inode->i_fop = &proc_info_file_operations;
1653 ei->op.proc_read = proc_tid_stat;
1654 break;
1655 case PROC_TGID_STAT:
1656 inode->i_fop = &proc_info_file_operations;
1657 ei->op.proc_read = proc_tgid_stat;
1658 break;
1659 case PROC_TID_CMDLINE:
1660 case PROC_TGID_CMDLINE:
1661 inode->i_fop = &proc_info_file_operations;
1662 ei->op.proc_read = proc_pid_cmdline;
1663 break;
1664 case PROC_TID_STATM:
1665 case PROC_TGID_STATM:
1666 inode->i_fop = &proc_info_file_operations;
1667 ei->op.proc_read = proc_pid_statm;
1668 break;
1669 case PROC_TID_MAPS:
1670 case PROC_TGID_MAPS:
1671 inode->i_fop = &proc_maps_operations;
1672 break;
6e21c8f1
CL		 1673#ifdef CONFIG_NUMA
1674 case PROC_TID_NUMA_MAPS:
1675 case PROC_TGID_NUMA_MAPS:
1676 inode->i_fop = &proc_numa_maps_operations;
1677 break;
1678#endif
1da177e4
LT		 1679 case PROC_TID_MEM:
1680 case PROC_TGID_MEM:
1681 inode->i_op = &proc_mem_inode_operations;
1682 inode->i_fop = &proc_mem_operations;
1683 break;
1684#ifdef CONFIG_SECCOMP
1685 case PROC_TID_SECCOMP:
1686 case PROC_TGID_SECCOMP:
1687 inode->i_fop = &proc_seccomp_operations;
1688 break;
1689#endif /* CONFIG_SECCOMP */
1690 case PROC_TID_MOUNTS:
1691 case PROC_TGID_MOUNTS:
1692 inode->i_fop = &proc_mounts_operations;
1693 break;
63c6764c 1694#ifdef CONFIG_MMU
e070ad49
ML		 1695 case PROC_TID_SMAPS:
1696 case PROC_TGID_SMAPS:
1697 inode->i_fop = &proc_smaps_operations;
1698 break;
63c6764c 1699#endif
1da177e4
LT		 1700#ifdef CONFIG_SECURITY
1701 case PROC_TID_ATTR:
1702 inode->i_nlink = 2;
1703 inode->i_op = &proc_tid_attr_inode_operations;
1704 inode->i_fop = &proc_tid_attr_operations;
1705 break;
1706 case PROC_TGID_ATTR:
1707 inode->i_nlink = 2;
1708 inode->i_op = &proc_tgid_attr_inode_operations;
1709 inode->i_fop = &proc_tgid_attr_operations;
1710 break;
1711 case PROC_TID_ATTR_CURRENT:
1712 case PROC_TGID_ATTR_CURRENT:
1713 case PROC_TID_ATTR_PREV:
1714 case PROC_TGID_ATTR_PREV:
1715 case PROC_TID_ATTR_EXEC:
1716 case PROC_TGID_ATTR_EXEC:
1717 case PROC_TID_ATTR_FSCREATE:
1718 case PROC_TGID_ATTR_FSCREATE:
1719 inode->i_fop = &proc_pid_attr_operations;
1720 break;
1721#endif
1722#ifdef CONFIG_KALLSYMS
1723 case PROC_TID_WCHAN:
1724 case PROC_TGID_WCHAN:
1725 inode->i_fop = &proc_info_file_operations;
1726 ei->op.proc_read = proc_pid_wchan;
1727 break;
1728#endif
1729#ifdef CONFIG_SCHEDSTATS
1730 case PROC_TID_SCHEDSTAT:
1731 case PROC_TGID_SCHEDSTAT:
1732 inode->i_fop = &proc_info_file_operations;
1733 ei->op.proc_read = proc_pid_schedstat;
1734 break;
1735#endif
1736#ifdef CONFIG_CPUSETS
1737 case PROC_TID_CPUSET:
1738 case PROC_TGID_CPUSET:
1739 inode->i_fop = &proc_cpuset_operations;
1740 break;
1741#endif
1742 case PROC_TID_OOM_SCORE:
1743 case PROC_TGID_OOM_SCORE:
1744 inode->i_fop = &proc_info_file_operations;
1745 ei->op.proc_read = proc_oom_score;
1746 break;
1747 case PROC_TID_OOM_ADJUST:
1748 case PROC_TGID_OOM_ADJUST:
1749 inode->i_fop = &proc_oom_adjust_operations;
1750 break;
1751#ifdef CONFIG_AUDITSYSCALL
1752 case PROC_TID_LOGINUID:
1753 case PROC_TGID_LOGINUID:
1754 inode->i_fop = &proc_loginuid_operations;
1755 break;
1756#endif
1757 default:
1758 printk("procfs: impossible type (%d)",p->type);
1759 iput(inode);
1760 return ERR_PTR(-EINVAL);
1761 }
1762 dentry->d_op = &pid_dentry_operations;
1763 d_add(dentry, inode);
1764 return NULL;
1765
1766out:
1767 return ERR_PTR(error);
1768}
1769
1770static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
1771 return proc_pident_lookup(dir, dentry, tgid_base_stuff);
1772}
1773
1774static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
1775 return proc_pident_lookup(dir, dentry, tid_base_stuff);
1776}
1777
1778static struct file_operations proc_tgid_base_operations = {
1779 .read = generic_read_dir,
1780 .readdir = proc_tgid_base_readdir,
1781};
1782
1783static struct file_operations proc_tid_base_operations = {
1784 .read = generic_read_dir,
1785 .readdir = proc_tid_base_readdir,
1786};
1787
1788static struct inode_operations proc_tgid_base_inode_operations = {
1789 .lookup = proc_tgid_base_lookup,
1790};
1791
1792static struct inode_operations proc_tid_base_inode_operations = {
1793 .lookup = proc_tid_base_lookup,
1794};
1795
1796#ifdef CONFIG_SECURITY
1797static int proc_tgid_attr_readdir(struct file * filp,
1798 void * dirent, filldir_t filldir)
1799{
1800 return proc_pident_readdir(filp,dirent,filldir,
1801 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff));
1802}
1803
1804static int proc_tid_attr_readdir(struct file * filp,
1805 void * dirent, filldir_t filldir)
1806{
1807 return proc_pident_readdir(filp,dirent,filldir,
1808 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff));
1809}
1810
1811static struct file_operations proc_tgid_attr_operations = {
1812 .read = generic_read_dir,
1813 .readdir = proc_tgid_attr_readdir,
1814};
1815
1816static struct file_operations proc_tid_attr_operations = {
1817 .read = generic_read_dir,
1818 .readdir = proc_tid_attr_readdir,
1819};
1820
1821static struct dentry *proc_tgid_attr_lookup(struct inode *dir,
1822 struct dentry *dentry, struct nameidata *nd)
1823{
1824 return proc_pident_lookup(dir, dentry, tgid_attr_stuff);
1825}
1826
1827static struct dentry *proc_tid_attr_lookup(struct inode *dir,
1828 struct dentry *dentry, struct nameidata *nd)
1829{
1830 return proc_pident_lookup(dir, dentry, tid_attr_stuff);
1831}
1832
1833static struct inode_operations proc_tgid_attr_inode_operations = {
1834 .lookup = proc_tgid_attr_lookup,
1835};
1836
1837static struct inode_operations proc_tid_attr_inode_operations = {
1838 .lookup = proc_tid_attr_lookup,
1839};
1840#endif
1841
1842/*
1843 * /proc/self:
1844 */
1845static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
1846 int buflen)
1847{
1848 char tmp[30];
1849 sprintf(tmp, "%d", current->tgid);
1850 return vfs_readlink(dentry,buffer,buflen,tmp);
1851}
1852
008b150a 1853static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1854{
1855 char tmp[30];
1856 sprintf(tmp, "%d", current->tgid);
008b150a 1857 return ERR_PTR(vfs_follow_link(nd,tmp));
1da177e4
LT		 1858}
1859
1860static struct inode_operations proc_self_inode_operations = {
1861 .readlink = proc_self_readlink,
1862 .follow_link = proc_self_follow_link,
1863};
1864
1865/**
4dc3b16b 1866 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache.
1da177e4
LT		 1867 * @p: task that should be flushed.
1868 *
4dc3b16b 1869 * Drops the /proc/@pid dcache entry from the hash chains.
1da177e4 1870 *
4dc3b16b
PP		 1871 * Dropping /proc/@pid entries and detach_pid must be synchroneous,
1872 * otherwise e.g. /proc/@pid/exe might point to the wrong executable,
1da177e4
LT		 1873 * if the pid value is immediately reused. This is enforced by
1874 * - caller must acquire spin_lock(p->proc_lock)
1875 * - must be called before detach_pid()
1876 * - proc_pid_lookup acquires proc_lock, and checks that
1877 * the target is not dead by looking at the attach count
1878 * of PIDTYPE_PID.
1879 */
1880
1881struct dentry *proc_pid_unhash(struct task_struct *p)
1882{
1883 struct dentry *proc_dentry;
1884
1885 proc_dentry = p->proc_dentry;
1886 if (proc_dentry != NULL) {
1887
1888 spin_lock(&dcache_lock);
1889 spin_lock(&proc_dentry->d_lock);
1890 if (!d_unhashed(proc_dentry)) {
1891 dget_locked(proc_dentry);
1892 __d_drop(proc_dentry);
1893 spin_unlock(&proc_dentry->d_lock);
1894 } else {
1895 spin_unlock(&proc_dentry->d_lock);
1896 proc_dentry = NULL;
1897 }
1898 spin_unlock(&dcache_lock);
1899 }
1900 return proc_dentry;
1901}
1902
1903/**
4dc3b16b 1904 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries
67be2dd1 1905 * @proc_dentry: directoy to prune.
1da177e4
LT		 1906 *
1907 * Shrink the /proc directory that was used by the just killed thread.
1908 */
1909
1910void proc_pid_flush(struct dentry *proc_dentry)
1911{
1912 might_sleep();
1913 if(proc_dentry != NULL) {
1914 shrink_dcache_parent(proc_dentry);
1915 dput(proc_dentry);
1916 }
1917}
1918
1919/* SMP-safe */
1920struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
1921{
1922 struct task_struct *task;
1923 struct inode *inode;
1924 struct proc_inode *ei;
1925 unsigned tgid;
1926 int died;
1927
1928 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) {
1929 inode = new_inode(dir->i_sb);
1930 if (!inode)
1931 return ERR_PTR(-ENOMEM);
1932 ei = PROC_I(inode);
1933 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1934 inode->i_ino = fake_ino(0, PROC_TGID_INO);
1935 ei->pde = NULL;
1936 inode->i_mode = S_IFLNK|S_IRWXUGO;
1937 inode->i_uid = inode->i_gid = 0;
1938 inode->i_size = 64;
1939 inode->i_op = &proc_self_inode_operations;
1940 d_add(dentry, inode);
1941 return NULL;
1942 }
1943 tgid = name_to_int(dentry);
1944 if (tgid == ~0U)
1945 goto out;
1946
1947 read_lock(&tasklist_lock);
1948 task = find_task_by_pid(tgid);
1949 if (task)
1950 get_task_struct(task);
1951 read_unlock(&tasklist_lock);
1952 if (!task)
1953 goto out;
1954
1955 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);
1956
1957
1958 if (!inode) {
1959 put_task_struct(task);
1960 goto out;
1961 }
1962 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
1963 inode->i_op = &proc_tgid_base_inode_operations;
1964 inode->i_fop = &proc_tgid_base_operations;
1da177e4 1965 inode->i_flags|=S_IMMUTABLE;
bcf88e11
DD		 1966#ifdef CONFIG_SECURITY
1967 inode->i_nlink = 5;
1968#else
1969 inode->i_nlink = 4;
1970#endif
1da177e4
LT		 1971
1972 dentry->d_op = &pid_base_dentry_operations;
1973
1974 died = 0;
1975 d_add(dentry, inode);
1976 spin_lock(&task->proc_lock);
1977 task->proc_dentry = dentry;
1978 if (!pid_alive(task)) {
1979 dentry = proc_pid_unhash(task);
1980 died = 1;
1981 }
1982 spin_unlock(&task->proc_lock);
1983
1984 put_task_struct(task);
1985 if (died) {
1986 proc_pid_flush(dentry);
1987 goto out;
1988 }
1989 return NULL;
1990out:
1991 return ERR_PTR(-ENOENT);
1992}
1993
1994/* SMP-safe */
1995static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
1996{
1997 struct task_struct *task;
1998 struct task_struct *leader = proc_task(dir);
1999 struct inode *inode;
2000 unsigned tid;
2001
2002 tid = name_to_int(dentry);
2003 if (tid == ~0U)
2004 goto out;
2005
2006 read_lock(&tasklist_lock);
2007 task = find_task_by_pid(tid);
2008 if (task)
2009 get_task_struct(task);
2010 read_unlock(&tasklist_lock);
2011 if (!task)
2012 goto out;
2013 if (leader->tgid != task->tgid)
2014 goto out_drop_task;
2015
2016 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);
2017
2018
2019 if (!inode)
2020 goto out_drop_task;
2021 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2022 inode->i_op = &proc_tid_base_inode_operations;
2023 inode->i_fop = &proc_tid_base_operations;
1da177e4 2024 inode->i_flags|=S_IMMUTABLE;
bcf88e11
DD		 2025#ifdef CONFIG_SECURITY
2026 inode->i_nlink = 4;
2027#else
2028 inode->i_nlink = 3;
2029#endif
1da177e4
LT		 2030
2031 dentry->d_op = &pid_base_dentry_operations;
2032
2033 d_add(dentry, inode);
2034
2035 put_task_struct(task);
2036 return NULL;
2037out_drop_task:
2038 put_task_struct(task);
2039out:
2040 return ERR_PTR(-ENOENT);
2041}
2042
2043#define PROC_NUMBUF 10
2044#define PROC_MAXPIDS 20
2045
2046/*
2047 * Get a few tgid's to return for filldir - we need to hold the
2048 * tasklist lock while doing this, and we must release it before
2049 * we actually do the filldir itself, so we use a temp buffer..
2050 */
2051static int get_tgid_list(int index, unsigned long version, unsigned int *tgids)
2052{
2053 struct task_struct *p;
2054 int nr_tgids = 0;
2055
2056 index--;
2057 read_lock(&tasklist_lock);
2058 p = NULL;
2059 if (version) {
2060 p = find_task_by_pid(version);
2061 if (p && !thread_group_leader(p))
2062 p = NULL;
2063 }
2064
2065 if (p)
2066 index = 0;
2067 else
2068 p = next_task(&init_task);
2069
2070 for ( ; p != &init_task; p = next_task(p)) {
2071 int tgid = p->pid;
2072 if (!pid_alive(p))
2073 continue;
2074 if (--index >= 0)
2075 continue;
2076 tgids[nr_tgids] = tgid;
2077 nr_tgids++;
2078 if (nr_tgids >= PROC_MAXPIDS)
2079 break;
2080 }
2081 read_unlock(&tasklist_lock);
2082 return nr_tgids;
2083}
2084
2085/*
2086 * Get a few tid's to return for filldir - we need to hold the
2087 * tasklist lock while doing this, and we must release it before
2088 * we actually do the filldir itself, so we use a temp buffer..
2089 */
2090static int get_tid_list(int index, unsigned int *tids, struct inode *dir)
2091{
2092 struct task_struct *leader_task = proc_task(dir);
2093 struct task_struct *task = leader_task;
2094 int nr_tids = 0;
2095
2096 index -= 2;
2097 read_lock(&tasklist_lock);
2098 /*
2099 * The starting point task (leader_task) might be an already
2100 * unlinked task, which cannot be used to access the task-list
2101 * via next_thread().
2102 */
2103 if (pid_alive(task)) do {
2104 int tid = task->pid;
2105
2106 if (--index >= 0)
2107 continue;
f246315e
DD		 2108 if (tids != NULL)
2109 tids[nr_tids] = tid;
1da177e4
LT		 2110 nr_tids++;
2111 if (nr_tids >= PROC_MAXPIDS)
2112 break;
2113 } while ((task = next_thread(task)) != leader_task);
2114 read_unlock(&tasklist_lock);
2115 return nr_tids;
2116}
2117
2118/* for the /proc/ directory itself, after non-process stuff has been done */
2119int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
2120{
2121 unsigned int tgid_array[PROC_MAXPIDS];
2122 char buf[PROC_NUMBUF];
2123 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2124 unsigned int nr_tgids, i;
2125 int next_tgid;
2126
2127 if (!nr) {
2128 ino_t ino = fake_ino(0,PROC_TGID_INO);
2129 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0)
2130 return 0;
2131 filp->f_pos++;
2132 nr++;
2133 }
2134
2135 /* f_version caches the tgid value that the last readdir call couldn't
2136 * return. lseek aka telldir automagically resets f_version to 0.
2137 */
2138 next_tgid = filp->f_version;
2139 filp->f_version = 0;
2140 for (;;) {
2141 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array);
2142 if (!nr_tgids) {
2143 /* no more entries ! */
2144 break;
2145 }
2146 next_tgid = 0;
2147
2148 /* do not use the last found pid, reserve it for next_tgid */
2149 if (nr_tgids == PROC_MAXPIDS) {
2150 nr_tgids--;
2151 next_tgid = tgid_array[nr_tgids];
2152 }
2153
2154 for (i=0;i<nr_tgids;i++) {
2155 int tgid = tgid_array[i];
2156 ino_t ino = fake_ino(tgid,PROC_TGID_INO);
2157 unsigned long j = PROC_NUMBUF;
2158
2159 do
2160 buf[--j] = '0' + (tgid % 10);
2161 while ((tgid /= 10) != 0);
2162
2163 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) {
2164 /* returning this tgid failed, save it as the first
2165 * pid for the next readir call */
2166 filp->f_version = tgid_array[i];
2167 goto out;
2168 }
2169 filp->f_pos++;
2170 nr++;
2171 }
2172 }
2173out:
2174 return 0;
2175}
2176
2177/* for the /proc/TGID/task/ directories */
2178static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
2179{
2180 unsigned int tid_array[PROC_MAXPIDS];
2181 char buf[PROC_NUMBUF];
2182 unsigned int nr_tids, i;
2183 struct dentry *dentry = filp->f_dentry;
2184 struct inode *inode = dentry->d_inode;
2185 int retval = -ENOENT;
2186 ino_t ino;
2187 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */
2188
2189 if (!pid_alive(proc_task(inode)))
2190 goto out;
2191 retval = 0;
2192
2193 switch (pos) {
2194 case 0:
2195 ino = inode->i_ino;
2196 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
2197 goto out;
2198 pos++;
2199 /* fall through */
2200 case 1:
2201 ino = parent_ino(dentry);
2202 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
2203 goto out;
2204 pos++;
2205 /* fall through */
2206 }
2207
2208 nr_tids = get_tid_list(pos, tid_array, inode);
f246315e 2209 inode->i_nlink = pos + nr_tids;
1da177e4
LT		 2210
2211 for (i = 0; i < nr_tids; i++) {
2212 unsigned long j = PROC_NUMBUF;
2213 int tid = tid_array[i];
2214
2215 ino = fake_ino(tid,PROC_TID_INO);
2216
2217 do
2218 buf[--j] = '0' + (tid % 10);
2219 while ((tid /= 10) != 0);
2220
2221 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0)
2222 break;
2223 pos++;
2224 }
2225out:
2226 filp->f_pos = pos;
2227 return retval;
2228}
kernel source for telekom puls (alcatel/mediatek)