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 | ||
1da177e4 LT |
52 | #include <linux/errno.h> |
53 | #include <linux/time.h> | |
54 | #include <linux/proc_fs.h> | |
55 | #include <linux/stat.h> | |
56 | #include <linux/init.h> | |
16f7e0fe | 57 | #include <linux/capability.h> |
1da177e4 LT |
58 | #include <linux/file.h> |
59 | #include <linux/string.h> | |
60 | #include <linux/seq_file.h> | |
61 | #include <linux/namei.h> | |
6b3286ed | 62 | #include <linux/mnt_namespace.h> |
1da177e4 | 63 | #include <linux/mm.h> |
b835996f | 64 | #include <linux/rcupdate.h> |
1da177e4 | 65 | #include <linux/kallsyms.h> |
5096add8 | 66 | #include <linux/module.h> |
1da177e4 LT |
67 | #include <linux/mount.h> |
68 | #include <linux/security.h> | |
69 | #include <linux/ptrace.h> | |
1da177e4 LT |
70 | #include <linux/cpuset.h> |
71 | #include <linux/audit.h> | |
5addc5dd | 72 | #include <linux/poll.h> |
1651e14e | 73 | #include <linux/nsproxy.h> |
8ac773b4 | 74 | #include <linux/oom.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 | 87 | |
8578cea7 | 88 | /* Worst case buffer size needed for holding an integer. */ |
0187f879 | 89 | #define PROC_NUMBUF 13 |
8578cea7 | 90 | |
1da177e4 | 91 | struct pid_entry { |
1da177e4 | 92 | char *name; |
c5141e6d | 93 | int len; |
1da177e4 | 94 | mode_t mode; |
c5ef1c42 | 95 | const struct inode_operations *iop; |
00977a59 | 96 | const struct file_operations *fop; |
20cdc894 | 97 | union proc_op op; |
1da177e4 LT |
98 | }; |
99 | ||
61a28784 | 100 | #define NOD(NAME, MODE, IOP, FOP, OP) { \ |
20cdc894 | 101 | .name = (NAME), \ |
c5141e6d | 102 | .len = sizeof(NAME) - 1, \ |
20cdc894 EB |
103 | .mode = MODE, \ |
104 | .iop = IOP, \ | |
105 | .fop = FOP, \ | |
106 | .op = OP, \ | |
107 | } | |
108 | ||
61a28784 EB |
109 | #define DIR(NAME, MODE, OTYPE) \ |
110 | NOD(NAME, (S_IFDIR|(MODE)), \ | |
20cdc894 EB |
111 | &proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations, \ |
112 | {} ) | |
61a28784 EB |
113 | #define LNK(NAME, OTYPE) \ |
114 | NOD(NAME, (S_IFLNK|S_IRWXUGO), \ | |
20cdc894 EB |
115 | &proc_pid_link_inode_operations, NULL, \ |
116 | { .proc_get_link = &proc_##OTYPE##_link } ) | |
61a28784 EB |
117 | #define REG(NAME, MODE, OTYPE) \ |
118 | NOD(NAME, (S_IFREG|(MODE)), NULL, \ | |
20cdc894 | 119 | &proc_##OTYPE##_operations, {}) |
61a28784 EB |
120 | #define INF(NAME, MODE, OTYPE) \ |
121 | NOD(NAME, (S_IFREG|(MODE)), \ | |
20cdc894 EB |
122 | NULL, &proc_info_file_operations, \ |
123 | { .proc_read = &proc_##OTYPE } ) | |
1da177e4 | 124 | |
5096add8 KC |
125 | int maps_protect; |
126 | EXPORT_SYMBOL(maps_protect); | |
127 | ||
0494f6ec | 128 | static struct fs_struct *get_fs_struct(struct task_struct *task) |
1da177e4 LT |
129 | { |
130 | struct fs_struct *fs; | |
0494f6ec MS |
131 | task_lock(task); |
132 | fs = task->fs; | |
1da177e4 LT |
133 | if(fs) |
134 | atomic_inc(&fs->count); | |
0494f6ec MS |
135 | task_unlock(task); |
136 | return fs; | |
137 | } | |
138 | ||
99f89551 EB |
139 | static int get_nr_threads(struct task_struct *tsk) |
140 | { | |
141 | /* Must be called with the rcu_read_lock held */ | |
142 | unsigned long flags; | |
143 | int count = 0; | |
144 | ||
145 | if (lock_task_sighand(tsk, &flags)) { | |
146 | count = atomic_read(&tsk->signal->count); | |
147 | unlock_task_sighand(tsk, &flags); | |
148 | } | |
149 | return count; | |
150 | } | |
151 | ||
0494f6ec MS |
152 | static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) |
153 | { | |
99f89551 EB |
154 | struct task_struct *task = get_proc_task(inode); |
155 | struct fs_struct *fs = NULL; | |
0494f6ec | 156 | int result = -ENOENT; |
99f89551 EB |
157 | |
158 | if (task) { | |
159 | fs = get_fs_struct(task); | |
160 | put_task_struct(task); | |
161 | } | |
1da177e4 LT |
162 | if (fs) { |
163 | read_lock(&fs->lock); | |
164 | *mnt = mntget(fs->pwdmnt); | |
165 | *dentry = dget(fs->pwd); | |
166 | read_unlock(&fs->lock); | |
167 | result = 0; | |
168 | put_fs_struct(fs); | |
169 | } | |
170 | return result; | |
171 | } | |
172 | ||
173 | static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) | |
174 | { | |
99f89551 EB |
175 | struct task_struct *task = get_proc_task(inode); |
176 | struct fs_struct *fs = NULL; | |
1da177e4 | 177 | int result = -ENOENT; |
99f89551 EB |
178 | |
179 | if (task) { | |
180 | fs = get_fs_struct(task); | |
181 | put_task_struct(task); | |
182 | } | |
1da177e4 LT |
183 | if (fs) { |
184 | read_lock(&fs->lock); | |
185 | *mnt = mntget(fs->rootmnt); | |
186 | *dentry = dget(fs->root); | |
187 | read_unlock(&fs->lock); | |
188 | result = 0; | |
189 | put_fs_struct(fs); | |
190 | } | |
191 | return result; | |
192 | } | |
193 | ||
194 | #define MAY_PTRACE(task) \ | |
195 | (task == current || \ | |
196 | (task->parent == current && \ | |
197 | (task->ptrace & PT_PTRACED) && \ | |
198 | (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ | |
199 | security_ptrace(current,task) == 0)) | |
200 | ||
1da177e4 LT |
201 | static int proc_pid_environ(struct task_struct *task, char * buffer) |
202 | { | |
203 | int res = 0; | |
204 | struct mm_struct *mm = get_task_mm(task); | |
205 | if (mm) { | |
da58a161 AD |
206 | unsigned int len; |
207 | ||
208 | res = -ESRCH; | |
209 | if (!ptrace_may_attach(task)) | |
210 | goto out; | |
211 | ||
212 | len = mm->env_end - mm->env_start; | |
1da177e4 LT |
213 | if (len > PAGE_SIZE) |
214 | len = PAGE_SIZE; | |
215 | res = access_process_vm(task, mm->env_start, buffer, len, 0); | |
da58a161 | 216 | out: |
1da177e4 LT |
217 | mmput(mm); |
218 | } | |
219 | return res; | |
220 | } | |
221 | ||
222 | static int proc_pid_cmdline(struct task_struct *task, char * buffer) | |
223 | { | |
224 | int res = 0; | |
225 | unsigned int len; | |
226 | struct mm_struct *mm = get_task_mm(task); | |
227 | if (!mm) | |
228 | goto out; | |
229 | if (!mm->arg_end) | |
230 | goto out_mm; /* Shh! No looking before we're done */ | |
231 | ||
232 | len = mm->arg_end - mm->arg_start; | |
233 | ||
234 | if (len > PAGE_SIZE) | |
235 | len = PAGE_SIZE; | |
236 | ||
237 | res = access_process_vm(task, mm->arg_start, buffer, len, 0); | |
238 | ||
239 | // If the nul at the end of args has been overwritten, then | |
240 | // assume application is using setproctitle(3). | |
241 | if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { | |
242 | len = strnlen(buffer, res); | |
243 | if (len < res) { | |
244 | res = len; | |
245 | } else { | |
246 | len = mm->env_end - mm->env_start; | |
247 | if (len > PAGE_SIZE - res) | |
248 | len = PAGE_SIZE - res; | |
249 | res += access_process_vm(task, mm->env_start, buffer+res, len, 0); | |
250 | res = strnlen(buffer, res); | |
251 | } | |
252 | } | |
253 | out_mm: | |
254 | mmput(mm); | |
255 | out: | |
256 | return res; | |
257 | } | |
258 | ||
259 | static int proc_pid_auxv(struct task_struct *task, char *buffer) | |
260 | { | |
261 | int res = 0; | |
262 | struct mm_struct *mm = get_task_mm(task); | |
263 | if (mm) { | |
264 | unsigned int nwords = 0; | |
265 | do | |
266 | nwords += 2; | |
267 | while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ | |
268 | res = nwords * sizeof(mm->saved_auxv[0]); | |
269 | if (res > PAGE_SIZE) | |
270 | res = PAGE_SIZE; | |
271 | memcpy(buffer, mm->saved_auxv, res); | |
272 | mmput(mm); | |
273 | } | |
274 | return res; | |
275 | } | |
276 | ||
277 | ||
278 | #ifdef CONFIG_KALLSYMS | |
279 | /* | |
280 | * Provides a wchan file via kallsyms in a proper one-value-per-file format. | |
281 | * Returns the resolved symbol. If that fails, simply return the address. | |
282 | */ | |
283 | static int proc_pid_wchan(struct task_struct *task, char *buffer) | |
284 | { | |
ffb45122 | 285 | unsigned long wchan; |
9d65cb4a | 286 | char symname[KSYM_NAME_LEN+1]; |
1da177e4 LT |
287 | |
288 | wchan = get_wchan(task); | |
289 | ||
9d65cb4a AD |
290 | if (lookup_symbol_name(wchan, symname) < 0) |
291 | return sprintf(buffer, "%lu", wchan); | |
292 | else | |
293 | return sprintf(buffer, "%s", symname); | |
1da177e4 LT |
294 | } |
295 | #endif /* CONFIG_KALLSYMS */ | |
296 | ||
297 | #ifdef CONFIG_SCHEDSTATS | |
298 | /* | |
299 | * Provides /proc/PID/schedstat | |
300 | */ | |
301 | static int proc_pid_schedstat(struct task_struct *task, char *buffer) | |
302 | { | |
172ba844 | 303 | return sprintf(buffer, "%llu %llu %lu\n", |
1da177e4 LT |
304 | task->sched_info.cpu_time, |
305 | task->sched_info.run_delay, | |
306 | task->sched_info.pcnt); | |
307 | } | |
308 | #endif | |
309 | ||
310 | /* The badness from the OOM killer */ | |
311 | unsigned long badness(struct task_struct *p, unsigned long uptime); | |
312 | static int proc_oom_score(struct task_struct *task, char *buffer) | |
313 | { | |
314 | unsigned long points; | |
315 | struct timespec uptime; | |
316 | ||
317 | do_posix_clock_monotonic_gettime(&uptime); | |
19c5d45a | 318 | read_lock(&tasklist_lock); |
1da177e4 | 319 | points = badness(task, uptime.tv_sec); |
19c5d45a | 320 | read_unlock(&tasklist_lock); |
1da177e4 LT |
321 | return sprintf(buffer, "%lu\n", points); |
322 | } | |
323 | ||
324 | /************************************************************************/ | |
325 | /* Here the fs part begins */ | |
326 | /************************************************************************/ | |
327 | ||
328 | /* permission checks */ | |
778c1144 | 329 | static int proc_fd_access_allowed(struct inode *inode) |
1da177e4 | 330 | { |
778c1144 EB |
331 | struct task_struct *task; |
332 | int allowed = 0; | |
df26c40e EB |
333 | /* Allow access to a task's file descriptors if it is us or we |
334 | * may use ptrace attach to the process and find out that | |
335 | * information. | |
778c1144 EB |
336 | */ |
337 | task = get_proc_task(inode); | |
df26c40e EB |
338 | if (task) { |
339 | allowed = ptrace_may_attach(task); | |
778c1144 | 340 | put_task_struct(task); |
df26c40e | 341 | } |
778c1144 | 342 | return allowed; |
1da177e4 LT |
343 | } |
344 | ||
6d76fa58 LT |
345 | static int proc_setattr(struct dentry *dentry, struct iattr *attr) |
346 | { | |
347 | int error; | |
348 | struct inode *inode = dentry->d_inode; | |
349 | ||
350 | if (attr->ia_valid & ATTR_MODE) | |
351 | return -EPERM; | |
352 | ||
353 | error = inode_change_ok(inode, attr); | |
1e8123fd JJ |
354 | if (!error) |
355 | error = inode_setattr(inode, attr); | |
6d76fa58 LT |
356 | return error; |
357 | } | |
358 | ||
c5ef1c42 | 359 | static const struct inode_operations proc_def_inode_operations = { |
6d76fa58 LT |
360 | .setattr = proc_setattr, |
361 | }; | |
362 | ||
1da177e4 | 363 | extern struct seq_operations mounts_op; |
5addc5dd AV |
364 | struct proc_mounts { |
365 | struct seq_file m; | |
366 | int event; | |
367 | }; | |
368 | ||
1da177e4 LT |
369 | static int mounts_open(struct inode *inode, struct file *file) |
370 | { | |
99f89551 | 371 | struct task_struct *task = get_proc_task(inode); |
6b3286ed | 372 | struct mnt_namespace *ns = NULL; |
5addc5dd AV |
373 | struct proc_mounts *p; |
374 | int ret = -EINVAL; | |
1da177e4 | 375 | |
99f89551 EB |
376 | if (task) { |
377 | task_lock(task); | |
863c4702 AD |
378 | if (task->nsproxy) { |
379 | ns = task->nsproxy->mnt_ns; | |
380 | if (ns) | |
381 | get_mnt_ns(ns); | |
382 | } | |
99f89551 EB |
383 | task_unlock(task); |
384 | put_task_struct(task); | |
385 | } | |
5addc5dd | 386 | |
6b3286ed | 387 | if (ns) { |
5addc5dd AV |
388 | ret = -ENOMEM; |
389 | p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); | |
390 | if (p) { | |
391 | file->private_data = &p->m; | |
392 | ret = seq_open(file, &mounts_op); | |
393 | if (!ret) { | |
6b3286ed KK |
394 | p->m.private = ns; |
395 | p->event = ns->event; | |
5addc5dd AV |
396 | return 0; |
397 | } | |
398 | kfree(p); | |
1da177e4 | 399 | } |
6b3286ed | 400 | put_mnt_ns(ns); |
1da177e4 LT |
401 | } |
402 | return ret; | |
403 | } | |
404 | ||
405 | static int mounts_release(struct inode *inode, struct file *file) | |
406 | { | |
407 | struct seq_file *m = file->private_data; | |
6b3286ed KK |
408 | struct mnt_namespace *ns = m->private; |
409 | put_mnt_ns(ns); | |
1da177e4 LT |
410 | return seq_release(inode, file); |
411 | } | |
412 | ||
5addc5dd AV |
413 | static unsigned mounts_poll(struct file *file, poll_table *wait) |
414 | { | |
415 | struct proc_mounts *p = file->private_data; | |
6b3286ed | 416 | struct mnt_namespace *ns = p->m.private; |
5addc5dd AV |
417 | unsigned res = 0; |
418 | ||
419 | poll_wait(file, &ns->poll, wait); | |
420 | ||
421 | spin_lock(&vfsmount_lock); | |
422 | if (p->event != ns->event) { | |
423 | p->event = ns->event; | |
424 | res = POLLERR; | |
425 | } | |
426 | spin_unlock(&vfsmount_lock); | |
427 | ||
428 | return res; | |
429 | } | |
430 | ||
00977a59 | 431 | static const struct file_operations proc_mounts_operations = { |
1da177e4 LT |
432 | .open = mounts_open, |
433 | .read = seq_read, | |
434 | .llseek = seq_lseek, | |
435 | .release = mounts_release, | |
5addc5dd | 436 | .poll = mounts_poll, |
1da177e4 LT |
437 | }; |
438 | ||
b4629fe2 CL |
439 | extern struct seq_operations mountstats_op; |
440 | static int mountstats_open(struct inode *inode, struct file *file) | |
441 | { | |
b4629fe2 CL |
442 | int ret = seq_open(file, &mountstats_op); |
443 | ||
444 | if (!ret) { | |
445 | struct seq_file *m = file->private_data; | |
6b3286ed | 446 | struct mnt_namespace *mnt_ns = NULL; |
99f89551 EB |
447 | struct task_struct *task = get_proc_task(inode); |
448 | ||
449 | if (task) { | |
450 | task_lock(task); | |
701e054e | 451 | if (task->nsproxy) |
6b3286ed KK |
452 | mnt_ns = task->nsproxy->mnt_ns; |
453 | if (mnt_ns) | |
454 | get_mnt_ns(mnt_ns); | |
99f89551 EB |
455 | task_unlock(task); |
456 | put_task_struct(task); | |
457 | } | |
b4629fe2 | 458 | |
6b3286ed KK |
459 | if (mnt_ns) |
460 | m->private = mnt_ns; | |
b4629fe2 CL |
461 | else { |
462 | seq_release(inode, file); | |
463 | ret = -EINVAL; | |
464 | } | |
465 | } | |
466 | return ret; | |
467 | } | |
468 | ||
00977a59 | 469 | static const struct file_operations proc_mountstats_operations = { |
b4629fe2 CL |
470 | .open = mountstats_open, |
471 | .read = seq_read, | |
472 | .llseek = seq_lseek, | |
473 | .release = mounts_release, | |
474 | }; | |
475 | ||
1da177e4 LT |
476 | #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ |
477 | ||
478 | static ssize_t proc_info_read(struct file * file, char __user * buf, | |
479 | size_t count, loff_t *ppos) | |
480 | { | |
2fddfeef | 481 | struct inode * inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
482 | unsigned long page; |
483 | ssize_t length; | |
99f89551 EB |
484 | struct task_struct *task = get_proc_task(inode); |
485 | ||
486 | length = -ESRCH; | |
487 | if (!task) | |
488 | goto out_no_task; | |
1da177e4 LT |
489 | |
490 | if (count > PROC_BLOCK_SIZE) | |
491 | count = PROC_BLOCK_SIZE; | |
99f89551 EB |
492 | |
493 | length = -ENOMEM; | |
1da177e4 | 494 | if (!(page = __get_free_page(GFP_KERNEL))) |
99f89551 | 495 | goto out; |
1da177e4 LT |
496 | |
497 | length = PROC_I(inode)->op.proc_read(task, (char*)page); | |
498 | ||
499 | if (length >= 0) | |
500 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
501 | free_page(page); | |
99f89551 EB |
502 | out: |
503 | put_task_struct(task); | |
504 | out_no_task: | |
1da177e4 LT |
505 | return length; |
506 | } | |
507 | ||
00977a59 | 508 | static const struct file_operations proc_info_file_operations = { |
1da177e4 LT |
509 | .read = proc_info_read, |
510 | }; | |
511 | ||
512 | static int mem_open(struct inode* inode, struct file* file) | |
513 | { | |
514 | file->private_data = (void*)((long)current->self_exec_id); | |
515 | return 0; | |
516 | } | |
517 | ||
518 | static ssize_t mem_read(struct file * file, char __user * buf, | |
519 | size_t count, loff_t *ppos) | |
520 | { | |
2fddfeef | 521 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); |
1da177e4 LT |
522 | char *page; |
523 | unsigned long src = *ppos; | |
524 | int ret = -ESRCH; | |
525 | struct mm_struct *mm; | |
526 | ||
99f89551 EB |
527 | if (!task) |
528 | goto out_no_task; | |
529 | ||
ab8d11be | 530 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
1da177e4 LT |
531 | goto out; |
532 | ||
533 | ret = -ENOMEM; | |
534 | page = (char *)__get_free_page(GFP_USER); | |
535 | if (!page) | |
536 | goto out; | |
537 | ||
538 | ret = 0; | |
539 | ||
540 | mm = get_task_mm(task); | |
541 | if (!mm) | |
542 | goto out_free; | |
543 | ||
544 | ret = -EIO; | |
545 | ||
546 | if (file->private_data != (void*)((long)current->self_exec_id)) | |
547 | goto out_put; | |
548 | ||
549 | ret = 0; | |
550 | ||
551 | while (count > 0) { | |
552 | int this_len, retval; | |
553 | ||
554 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
555 | retval = access_process_vm(task, src, page, this_len, 0); | |
ab8d11be | 556 | if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { |
1da177e4 LT |
557 | if (!ret) |
558 | ret = -EIO; | |
559 | break; | |
560 | } | |
561 | ||
562 | if (copy_to_user(buf, page, retval)) { | |
563 | ret = -EFAULT; | |
564 | break; | |
565 | } | |
566 | ||
567 | ret += retval; | |
568 | src += retval; | |
569 | buf += retval; | |
570 | count -= retval; | |
571 | } | |
572 | *ppos = src; | |
573 | ||
574 | out_put: | |
575 | mmput(mm); | |
576 | out_free: | |
577 | free_page((unsigned long) page); | |
578 | out: | |
99f89551 EB |
579 | put_task_struct(task); |
580 | out_no_task: | |
1da177e4 LT |
581 | return ret; |
582 | } | |
583 | ||
584 | #define mem_write NULL | |
585 | ||
586 | #ifndef mem_write | |
587 | /* This is a security hazard */ | |
63967fa9 | 588 | static ssize_t mem_write(struct file * file, const char __user *buf, |
1da177e4 LT |
589 | size_t count, loff_t *ppos) |
590 | { | |
f7ca54f4 | 591 | int copied; |
1da177e4 | 592 | char *page; |
2fddfeef | 593 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); |
1da177e4 LT |
594 | unsigned long dst = *ppos; |
595 | ||
99f89551 EB |
596 | copied = -ESRCH; |
597 | if (!task) | |
598 | goto out_no_task; | |
599 | ||
ab8d11be | 600 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
99f89551 | 601 | goto out; |
1da177e4 | 602 | |
99f89551 | 603 | copied = -ENOMEM; |
1da177e4 LT |
604 | page = (char *)__get_free_page(GFP_USER); |
605 | if (!page) | |
99f89551 | 606 | goto out; |
1da177e4 | 607 | |
f7ca54f4 | 608 | copied = 0; |
1da177e4 LT |
609 | while (count > 0) { |
610 | int this_len, retval; | |
611 | ||
612 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
613 | if (copy_from_user(page, buf, this_len)) { | |
614 | copied = -EFAULT; | |
615 | break; | |
616 | } | |
617 | retval = access_process_vm(task, dst, page, this_len, 1); | |
618 | if (!retval) { | |
619 | if (!copied) | |
620 | copied = -EIO; | |
621 | break; | |
622 | } | |
623 | copied += retval; | |
624 | buf += retval; | |
625 | dst += retval; | |
626 | count -= retval; | |
627 | } | |
628 | *ppos = dst; | |
629 | free_page((unsigned long) page); | |
99f89551 EB |
630 | out: |
631 | put_task_struct(task); | |
632 | out_no_task: | |
1da177e4 LT |
633 | return copied; |
634 | } | |
635 | #endif | |
636 | ||
637 | static loff_t mem_lseek(struct file * file, loff_t offset, int orig) | |
638 | { | |
639 | switch (orig) { | |
640 | case 0: | |
641 | file->f_pos = offset; | |
642 | break; | |
643 | case 1: | |
644 | file->f_pos += offset; | |
645 | break; | |
646 | default: | |
647 | return -EINVAL; | |
648 | } | |
649 | force_successful_syscall_return(); | |
650 | return file->f_pos; | |
651 | } | |
652 | ||
00977a59 | 653 | static const struct file_operations proc_mem_operations = { |
1da177e4 LT |
654 | .llseek = mem_lseek, |
655 | .read = mem_read, | |
656 | .write = mem_write, | |
657 | .open = mem_open, | |
658 | }; | |
659 | ||
660 | static ssize_t oom_adjust_read(struct file *file, char __user *buf, | |
661 | size_t count, loff_t *ppos) | |
662 | { | |
2fddfeef | 663 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); |
8578cea7 | 664 | char buffer[PROC_NUMBUF]; |
1da177e4 | 665 | size_t len; |
99f89551 | 666 | int oom_adjust; |
1da177e4 | 667 | |
99f89551 EB |
668 | if (!task) |
669 | return -ESRCH; | |
670 | oom_adjust = task->oomkilladj; | |
671 | put_task_struct(task); | |
672 | ||
8578cea7 | 673 | len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); |
0c28f287 AM |
674 | |
675 | return simple_read_from_buffer(buf, count, ppos, buffer, len); | |
1da177e4 LT |
676 | } |
677 | ||
678 | static ssize_t oom_adjust_write(struct file *file, const char __user *buf, | |
679 | size_t count, loff_t *ppos) | |
680 | { | |
99f89551 | 681 | struct task_struct *task; |
8578cea7 | 682 | char buffer[PROC_NUMBUF], *end; |
1da177e4 LT |
683 | int oom_adjust; |
684 | ||
8578cea7 EB |
685 | memset(buffer, 0, sizeof(buffer)); |
686 | if (count > sizeof(buffer) - 1) | |
687 | count = sizeof(buffer) - 1; | |
1da177e4 LT |
688 | if (copy_from_user(buffer, buf, count)) |
689 | return -EFAULT; | |
690 | oom_adjust = simple_strtol(buffer, &end, 0); | |
8ac773b4 AD |
691 | if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && |
692 | oom_adjust != OOM_DISABLE) | |
1da177e4 LT |
693 | return -EINVAL; |
694 | if (*end == '\n') | |
695 | end++; | |
2fddfeef | 696 | task = get_proc_task(file->f_path.dentry->d_inode); |
99f89551 EB |
697 | if (!task) |
698 | return -ESRCH; | |
8fb4fc68 GJ |
699 | if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) { |
700 | put_task_struct(task); | |
701 | return -EACCES; | |
702 | } | |
1da177e4 | 703 | task->oomkilladj = oom_adjust; |
99f89551 | 704 | put_task_struct(task); |
1da177e4 LT |
705 | if (end - buffer == 0) |
706 | return -EIO; | |
707 | return end - buffer; | |
708 | } | |
709 | ||
00977a59 | 710 | static const struct file_operations proc_oom_adjust_operations = { |
1da177e4 LT |
711 | .read = oom_adjust_read, |
712 | .write = oom_adjust_write, | |
713 | }; | |
714 | ||
4b8df891 | 715 | #ifdef CONFIG_MMU |
b813e931 DR |
716 | static ssize_t clear_refs_write(struct file *file, const char __user *buf, |
717 | size_t count, loff_t *ppos) | |
718 | { | |
719 | struct task_struct *task; | |
720 | char buffer[PROC_NUMBUF], *end; | |
721 | struct mm_struct *mm; | |
722 | ||
723 | memset(buffer, 0, sizeof(buffer)); | |
724 | if (count > sizeof(buffer) - 1) | |
725 | count = sizeof(buffer) - 1; | |
726 | if (copy_from_user(buffer, buf, count)) | |
727 | return -EFAULT; | |
728 | if (!simple_strtol(buffer, &end, 0)) | |
729 | return -EINVAL; | |
730 | if (*end == '\n') | |
731 | end++; | |
732 | task = get_proc_task(file->f_path.dentry->d_inode); | |
733 | if (!task) | |
734 | return -ESRCH; | |
735 | mm = get_task_mm(task); | |
736 | if (mm) { | |
737 | clear_refs_smap(mm); | |
738 | mmput(mm); | |
739 | } | |
740 | put_task_struct(task); | |
741 | if (end - buffer == 0) | |
742 | return -EIO; | |
743 | return end - buffer; | |
744 | } | |
745 | ||
746 | static struct file_operations proc_clear_refs_operations = { | |
747 | .write = clear_refs_write, | |
748 | }; | |
4b8df891 | 749 | #endif |
b813e931 | 750 | |
1da177e4 LT |
751 | #ifdef CONFIG_AUDITSYSCALL |
752 | #define TMPBUFLEN 21 | |
753 | static ssize_t proc_loginuid_read(struct file * file, char __user * buf, | |
754 | size_t count, loff_t *ppos) | |
755 | { | |
2fddfeef | 756 | struct inode * inode = file->f_path.dentry->d_inode; |
99f89551 | 757 | struct task_struct *task = get_proc_task(inode); |
1da177e4 LT |
758 | ssize_t length; |
759 | char tmpbuf[TMPBUFLEN]; | |
760 | ||
99f89551 EB |
761 | if (!task) |
762 | return -ESRCH; | |
1da177e4 LT |
763 | length = scnprintf(tmpbuf, TMPBUFLEN, "%u", |
764 | audit_get_loginuid(task->audit_context)); | |
99f89551 | 765 | put_task_struct(task); |
1da177e4 LT |
766 | return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); |
767 | } | |
768 | ||
769 | static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, | |
770 | size_t count, loff_t *ppos) | |
771 | { | |
2fddfeef | 772 | struct inode * inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
773 | char *page, *tmp; |
774 | ssize_t length; | |
1da177e4 LT |
775 | uid_t loginuid; |
776 | ||
777 | if (!capable(CAP_AUDIT_CONTROL)) | |
778 | return -EPERM; | |
779 | ||
13b41b09 | 780 | if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) |
1da177e4 LT |
781 | return -EPERM; |
782 | ||
e0182909 AV |
783 | if (count >= PAGE_SIZE) |
784 | count = PAGE_SIZE - 1; | |
1da177e4 LT |
785 | |
786 | if (*ppos != 0) { | |
787 | /* No partial writes. */ | |
788 | return -EINVAL; | |
789 | } | |
790 | page = (char*)__get_free_page(GFP_USER); | |
791 | if (!page) | |
792 | return -ENOMEM; | |
793 | length = -EFAULT; | |
794 | if (copy_from_user(page, buf, count)) | |
795 | goto out_free_page; | |
796 | ||
e0182909 | 797 | page[count] = '\0'; |
1da177e4 LT |
798 | loginuid = simple_strtoul(page, &tmp, 10); |
799 | if (tmp == page) { | |
800 | length = -EINVAL; | |
801 | goto out_free_page; | |
802 | ||
803 | } | |
99f89551 | 804 | length = audit_set_loginuid(current, loginuid); |
1da177e4 LT |
805 | if (likely(length == 0)) |
806 | length = count; | |
807 | ||
808 | out_free_page: | |
809 | free_page((unsigned long) page); | |
810 | return length; | |
811 | } | |
812 | ||
00977a59 | 813 | static const struct file_operations proc_loginuid_operations = { |
1da177e4 LT |
814 | .read = proc_loginuid_read, |
815 | .write = proc_loginuid_write, | |
816 | }; | |
817 | #endif | |
818 | ||
f4f154fd AM |
819 | #ifdef CONFIG_FAULT_INJECTION |
820 | static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, | |
821 | size_t count, loff_t *ppos) | |
822 | { | |
823 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); | |
824 | char buffer[PROC_NUMBUF]; | |
825 | size_t len; | |
826 | int make_it_fail; | |
f4f154fd AM |
827 | |
828 | if (!task) | |
829 | return -ESRCH; | |
830 | make_it_fail = task->make_it_fail; | |
831 | put_task_struct(task); | |
832 | ||
833 | len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); | |
0c28f287 AM |
834 | |
835 | return simple_read_from_buffer(buf, count, ppos, buffer, len); | |
f4f154fd AM |
836 | } |
837 | ||
838 | static ssize_t proc_fault_inject_write(struct file * file, | |
839 | const char __user * buf, size_t count, loff_t *ppos) | |
840 | { | |
841 | struct task_struct *task; | |
842 | char buffer[PROC_NUMBUF], *end; | |
843 | int make_it_fail; | |
844 | ||
845 | if (!capable(CAP_SYS_RESOURCE)) | |
846 | return -EPERM; | |
847 | memset(buffer, 0, sizeof(buffer)); | |
848 | if (count > sizeof(buffer) - 1) | |
849 | count = sizeof(buffer) - 1; | |
850 | if (copy_from_user(buffer, buf, count)) | |
851 | return -EFAULT; | |
852 | make_it_fail = simple_strtol(buffer, &end, 0); | |
853 | if (*end == '\n') | |
854 | end++; | |
855 | task = get_proc_task(file->f_dentry->d_inode); | |
856 | if (!task) | |
857 | return -ESRCH; | |
858 | task->make_it_fail = make_it_fail; | |
859 | put_task_struct(task); | |
860 | if (end - buffer == 0) | |
861 | return -EIO; | |
862 | return end - buffer; | |
863 | } | |
864 | ||
00977a59 | 865 | static const struct file_operations proc_fault_inject_operations = { |
f4f154fd AM |
866 | .read = proc_fault_inject_read, |
867 | .write = proc_fault_inject_write, | |
868 | }; | |
869 | #endif | |
870 | ||
43ae34cb IM |
871 | #ifdef CONFIG_SCHED_DEBUG |
872 | /* | |
873 | * Print out various scheduling related per-task fields: | |
874 | */ | |
875 | static int sched_show(struct seq_file *m, void *v) | |
876 | { | |
877 | struct inode *inode = m->private; | |
878 | struct task_struct *p; | |
879 | ||
880 | WARN_ON(!inode); | |
881 | ||
882 | p = get_proc_task(inode); | |
883 | if (!p) | |
884 | return -ESRCH; | |
885 | proc_sched_show_task(p, m); | |
886 | ||
887 | put_task_struct(p); | |
888 | ||
889 | return 0; | |
890 | } | |
891 | ||
892 | static ssize_t | |
893 | sched_write(struct file *file, const char __user *buf, | |
894 | size_t count, loff_t *offset) | |
895 | { | |
896 | struct inode *inode = file->f_path.dentry->d_inode; | |
897 | struct task_struct *p; | |
898 | ||
899 | WARN_ON(!inode); | |
900 | ||
901 | p = get_proc_task(inode); | |
902 | if (!p) | |
903 | return -ESRCH; | |
904 | proc_sched_set_task(p); | |
905 | ||
906 | put_task_struct(p); | |
907 | ||
908 | return count; | |
909 | } | |
910 | ||
911 | static int sched_open(struct inode *inode, struct file *filp) | |
912 | { | |
913 | int ret; | |
914 | ||
915 | ret = single_open(filp, sched_show, NULL); | |
916 | if (!ret) { | |
917 | struct seq_file *m = filp->private_data; | |
918 | ||
919 | m->private = inode; | |
920 | } | |
921 | return ret; | |
922 | } | |
923 | ||
924 | static const struct file_operations proc_pid_sched_operations = { | |
925 | .open = sched_open, | |
926 | .read = seq_read, | |
927 | .write = sched_write, | |
928 | .llseek = seq_lseek, | |
929 | .release = seq_release, | |
930 | }; | |
931 | ||
932 | #endif | |
933 | ||
008b150a | 934 | static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
935 | { |
936 | struct inode *inode = dentry->d_inode; | |
937 | int error = -EACCES; | |
938 | ||
939 | /* We don't need a base pointer in the /proc filesystem */ | |
940 | path_release(nd); | |
941 | ||
778c1144 EB |
942 | /* Are we allowed to snoop on the tasks file descriptors? */ |
943 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 944 | goto out; |
1da177e4 LT |
945 | |
946 | error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); | |
947 | nd->last_type = LAST_BIND; | |
948 | out: | |
008b150a | 949 | return ERR_PTR(error); |
1da177e4 LT |
950 | } |
951 | ||
952 | static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, | |
953 | char __user *buffer, int buflen) | |
954 | { | |
955 | struct inode * inode; | |
956 | char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; | |
957 | int len; | |
958 | ||
959 | if (!tmp) | |
960 | return -ENOMEM; | |
0c28f287 | 961 | |
1da177e4 LT |
962 | inode = dentry->d_inode; |
963 | path = d_path(dentry, mnt, tmp, PAGE_SIZE); | |
964 | len = PTR_ERR(path); | |
965 | if (IS_ERR(path)) | |
966 | goto out; | |
967 | len = tmp + PAGE_SIZE - 1 - path; | |
968 | ||
969 | if (len > buflen) | |
970 | len = buflen; | |
971 | if (copy_to_user(buffer, path, len)) | |
972 | len = -EFAULT; | |
973 | out: | |
974 | free_page((unsigned long)tmp); | |
975 | return len; | |
976 | } | |
977 | ||
978 | static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) | |
979 | { | |
980 | int error = -EACCES; | |
981 | struct inode *inode = dentry->d_inode; | |
982 | struct dentry *de; | |
983 | struct vfsmount *mnt = NULL; | |
984 | ||
778c1144 EB |
985 | /* Are we allowed to snoop on the tasks file descriptors? */ |
986 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 987 | goto out; |
1da177e4 LT |
988 | |
989 | error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); | |
990 | if (error) | |
991 | goto out; | |
992 | ||
993 | error = do_proc_readlink(de, mnt, buffer, buflen); | |
994 | dput(de); | |
995 | mntput(mnt); | |
996 | out: | |
1da177e4 LT |
997 | return error; |
998 | } | |
999 | ||
c5ef1c42 | 1000 | static const struct inode_operations proc_pid_link_inode_operations = { |
1da177e4 | 1001 | .readlink = proc_pid_readlink, |
6d76fa58 LT |
1002 | .follow_link = proc_pid_follow_link, |
1003 | .setattr = proc_setattr, | |
1da177e4 LT |
1004 | }; |
1005 | ||
28a6d671 EB |
1006 | |
1007 | /* building an inode */ | |
1008 | ||
1009 | static int task_dumpable(struct task_struct *task) | |
1da177e4 | 1010 | { |
28a6d671 EB |
1011 | int dumpable = 0; |
1012 | struct mm_struct *mm; | |
1da177e4 | 1013 | |
28a6d671 EB |
1014 | task_lock(task); |
1015 | mm = task->mm; | |
1016 | if (mm) | |
1017 | dumpable = mm->dumpable; | |
1018 | task_unlock(task); | |
1019 | if(dumpable == 1) | |
1020 | return 1; | |
1021 | return 0; | |
1022 | } | |
1da177e4 | 1023 | |
1da177e4 | 1024 | |
61a28784 | 1025 | static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) |
28a6d671 EB |
1026 | { |
1027 | struct inode * inode; | |
1028 | struct proc_inode *ei; | |
1da177e4 | 1029 | |
28a6d671 | 1030 | /* We need a new inode */ |
1da177e4 | 1031 | |
28a6d671 EB |
1032 | inode = new_inode(sb); |
1033 | if (!inode) | |
1034 | goto out; | |
1035 | ||
1036 | /* Common stuff */ | |
1037 | ei = PROC_I(inode); | |
1038 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
28a6d671 EB |
1039 | inode->i_op = &proc_def_inode_operations; |
1040 | ||
1041 | /* | |
1042 | * grab the reference to task. | |
1043 | */ | |
1a657f78 | 1044 | ei->pid = get_task_pid(task, PIDTYPE_PID); |
28a6d671 EB |
1045 | if (!ei->pid) |
1046 | goto out_unlock; | |
1047 | ||
1048 | inode->i_uid = 0; | |
1049 | inode->i_gid = 0; | |
1050 | if (task_dumpable(task)) { | |
1051 | inode->i_uid = task->euid; | |
1052 | inode->i_gid = task->egid; | |
1da177e4 | 1053 | } |
28a6d671 EB |
1054 | security_task_to_inode(task, inode); |
1055 | ||
1da177e4 | 1056 | out: |
28a6d671 EB |
1057 | return inode; |
1058 | ||
1059 | out_unlock: | |
1060 | iput(inode); | |
1061 | return NULL; | |
1da177e4 LT |
1062 | } |
1063 | ||
28a6d671 | 1064 | static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) |
1da177e4 | 1065 | { |
1da177e4 | 1066 | struct inode *inode = dentry->d_inode; |
28a6d671 EB |
1067 | struct task_struct *task; |
1068 | generic_fillattr(inode, stat); | |
1da177e4 | 1069 | |
28a6d671 EB |
1070 | rcu_read_lock(); |
1071 | stat->uid = 0; | |
1072 | stat->gid = 0; | |
1073 | task = pid_task(proc_pid(inode), PIDTYPE_PID); | |
1074 | if (task) { | |
1075 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1076 | task_dumpable(task)) { | |
1077 | stat->uid = task->euid; | |
1078 | stat->gid = task->egid; | |
1da177e4 LT |
1079 | } |
1080 | } | |
28a6d671 | 1081 | rcu_read_unlock(); |
d6e71144 | 1082 | return 0; |
1da177e4 LT |
1083 | } |
1084 | ||
1da177e4 LT |
1085 | /* dentry stuff */ |
1086 | ||
1087 | /* | |
1088 | * Exceptional case: normally we are not allowed to unhash a busy | |
1089 | * directory. In this case, however, we can do it - no aliasing problems | |
1090 | * due to the way we treat inodes. | |
1091 | * | |
1092 | * Rewrite the inode's ownerships here because the owning task may have | |
1093 | * performed a setuid(), etc. | |
99f89551 EB |
1094 | * |
1095 | * Before the /proc/pid/status file was created the only way to read | |
1096 | * the effective uid of a /process was to stat /proc/pid. Reading | |
1097 | * /proc/pid/status is slow enough that procps and other packages | |
1098 | * kept stating /proc/pid. To keep the rules in /proc simple I have | |
1099 | * made this apply to all per process world readable and executable | |
1100 | * directories. | |
1da177e4 LT |
1101 | */ |
1102 | static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1103 | { | |
1104 | struct inode *inode = dentry->d_inode; | |
99f89551 EB |
1105 | struct task_struct *task = get_proc_task(inode); |
1106 | if (task) { | |
1107 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1108 | task_dumpable(task)) { | |
1da177e4 LT |
1109 | inode->i_uid = task->euid; |
1110 | inode->i_gid = task->egid; | |
1111 | } else { | |
1112 | inode->i_uid = 0; | |
1113 | inode->i_gid = 0; | |
1114 | } | |
9ee8ab9f | 1115 | inode->i_mode &= ~(S_ISUID | S_ISGID); |
1da177e4 | 1116 | security_task_to_inode(task, inode); |
99f89551 | 1117 | put_task_struct(task); |
1da177e4 LT |
1118 | return 1; |
1119 | } | |
1120 | d_drop(dentry); | |
1121 | return 0; | |
1122 | } | |
1123 | ||
28a6d671 | 1124 | static int pid_delete_dentry(struct dentry * dentry) |
99f89551 | 1125 | { |
28a6d671 EB |
1126 | /* Is the task we represent dead? |
1127 | * If so, then don't put the dentry on the lru list, | |
1128 | * kill it immediately. | |
1129 | */ | |
1130 | return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; | |
1131 | } | |
1132 | ||
1133 | static struct dentry_operations pid_dentry_operations = | |
1134 | { | |
1135 | .d_revalidate = pid_revalidate, | |
1136 | .d_delete = pid_delete_dentry, | |
1137 | }; | |
1138 | ||
1139 | /* Lookups */ | |
1140 | ||
c5141e6d ED |
1141 | typedef struct dentry *instantiate_t(struct inode *, struct dentry *, |
1142 | struct task_struct *, const void *); | |
61a28784 | 1143 | |
1c0d04c9 EB |
1144 | /* |
1145 | * Fill a directory entry. | |
1146 | * | |
1147 | * If possible create the dcache entry and derive our inode number and | |
1148 | * file type from dcache entry. | |
1149 | * | |
1150 | * Since all of the proc inode numbers are dynamically generated, the inode | |
1151 | * numbers do not exist until the inode is cache. This means creating the | |
1152 | * the dcache entry in readdir is necessary to keep the inode numbers | |
1153 | * reported by readdir in sync with the inode numbers reported | |
1154 | * by stat. | |
1155 | */ | |
61a28784 EB |
1156 | static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1157 | char *name, int len, | |
c5141e6d | 1158 | instantiate_t instantiate, struct task_struct *task, const void *ptr) |
61a28784 | 1159 | { |
2fddfeef | 1160 | struct dentry *child, *dir = filp->f_path.dentry; |
61a28784 EB |
1161 | struct inode *inode; |
1162 | struct qstr qname; | |
1163 | ino_t ino = 0; | |
1164 | unsigned type = DT_UNKNOWN; | |
1165 | ||
1166 | qname.name = name; | |
1167 | qname.len = len; | |
1168 | qname.hash = full_name_hash(name, len); | |
1169 | ||
1170 | child = d_lookup(dir, &qname); | |
1171 | if (!child) { | |
1172 | struct dentry *new; | |
1173 | new = d_alloc(dir, &qname); | |
1174 | if (new) { | |
1175 | child = instantiate(dir->d_inode, new, task, ptr); | |
1176 | if (child) | |
1177 | dput(new); | |
1178 | else | |
1179 | child = new; | |
1180 | } | |
1181 | } | |
1182 | if (!child || IS_ERR(child) || !child->d_inode) | |
1183 | goto end_instantiate; | |
1184 | inode = child->d_inode; | |
1185 | if (inode) { | |
1186 | ino = inode->i_ino; | |
1187 | type = inode->i_mode >> 12; | |
1188 | } | |
1189 | dput(child); | |
1190 | end_instantiate: | |
1191 | if (!ino) | |
1192 | ino = find_inode_number(dir, &qname); | |
1193 | if (!ino) | |
1194 | ino = 1; | |
1195 | return filldir(dirent, name, len, filp->f_pos, ino, type); | |
1196 | } | |
1197 | ||
28a6d671 EB |
1198 | static unsigned name_to_int(struct dentry *dentry) |
1199 | { | |
1200 | const char *name = dentry->d_name.name; | |
1201 | int len = dentry->d_name.len; | |
1202 | unsigned n = 0; | |
1203 | ||
1204 | if (len > 1 && *name == '0') | |
1205 | goto out; | |
1206 | while (len-- > 0) { | |
1207 | unsigned c = *name++ - '0'; | |
1208 | if (c > 9) | |
1209 | goto out; | |
1210 | if (n >= (~0U-9)/10) | |
1211 | goto out; | |
1212 | n *= 10; | |
1213 | n += c; | |
1214 | } | |
1215 | return n; | |
1216 | out: | |
1217 | return ~0U; | |
1218 | } | |
1219 | ||
27932742 MS |
1220 | #define PROC_FDINFO_MAX 64 |
1221 | ||
1222 | static int proc_fd_info(struct inode *inode, struct dentry **dentry, | |
1223 | struct vfsmount **mnt, char *info) | |
28a6d671 EB |
1224 | { |
1225 | struct task_struct *task = get_proc_task(inode); | |
1226 | struct files_struct *files = NULL; | |
1227 | struct file *file; | |
1228 | int fd = proc_fd(inode); | |
99f89551 | 1229 | |
99f89551 | 1230 | if (task) { |
28a6d671 EB |
1231 | files = get_files_struct(task); |
1232 | put_task_struct(task); | |
1233 | } | |
1234 | if (files) { | |
1235 | /* | |
1236 | * We are not taking a ref to the file structure, so we must | |
1237 | * hold ->file_lock. | |
1238 | */ | |
1239 | spin_lock(&files->file_lock); | |
1240 | file = fcheck_files(files, fd); | |
1241 | if (file) { | |
27932742 MS |
1242 | if (mnt) |
1243 | *mnt = mntget(file->f_path.mnt); | |
1244 | if (dentry) | |
1245 | *dentry = dget(file->f_path.dentry); | |
1246 | if (info) | |
1247 | snprintf(info, PROC_FDINFO_MAX, | |
1248 | "pos:\t%lli\n" | |
1249 | "flags:\t0%o\n", | |
1250 | (long long) file->f_pos, | |
1251 | file->f_flags); | |
28a6d671 EB |
1252 | spin_unlock(&files->file_lock); |
1253 | put_files_struct(files); | |
1254 | return 0; | |
99f89551 | 1255 | } |
28a6d671 EB |
1256 | spin_unlock(&files->file_lock); |
1257 | put_files_struct(files); | |
99f89551 | 1258 | } |
28a6d671 | 1259 | return -ENOENT; |
99f89551 EB |
1260 | } |
1261 | ||
27932742 MS |
1262 | static int proc_fd_link(struct inode *inode, struct dentry **dentry, |
1263 | struct vfsmount **mnt) | |
1264 | { | |
1265 | return proc_fd_info(inode, dentry, mnt, NULL); | |
1266 | } | |
1267 | ||
1da177e4 LT |
1268 | static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) |
1269 | { | |
1270 | struct inode *inode = dentry->d_inode; | |
99f89551 | 1271 | struct task_struct *task = get_proc_task(inode); |
aed7a6c4 | 1272 | int fd = proc_fd(inode); |
1da177e4 LT |
1273 | struct files_struct *files; |
1274 | ||
99f89551 EB |
1275 | if (task) { |
1276 | files = get_files_struct(task); | |
1277 | if (files) { | |
1278 | rcu_read_lock(); | |
1279 | if (fcheck_files(files, fd)) { | |
1280 | rcu_read_unlock(); | |
1281 | put_files_struct(files); | |
1282 | if (task_dumpable(task)) { | |
1283 | inode->i_uid = task->euid; | |
1284 | inode->i_gid = task->egid; | |
1285 | } else { | |
1286 | inode->i_uid = 0; | |
1287 | inode->i_gid = 0; | |
1288 | } | |
9ee8ab9f | 1289 | inode->i_mode &= ~(S_ISUID | S_ISGID); |
99f89551 EB |
1290 | security_task_to_inode(task, inode); |
1291 | put_task_struct(task); | |
1292 | return 1; | |
1293 | } | |
b835996f | 1294 | rcu_read_unlock(); |
1da177e4 | 1295 | put_files_struct(files); |
1da177e4 | 1296 | } |
99f89551 | 1297 | put_task_struct(task); |
1da177e4 LT |
1298 | } |
1299 | d_drop(dentry); | |
1300 | return 0; | |
1301 | } | |
1302 | ||
1da177e4 LT |
1303 | static struct dentry_operations tid_fd_dentry_operations = |
1304 | { | |
1305 | .d_revalidate = tid_fd_revalidate, | |
1306 | .d_delete = pid_delete_dentry, | |
1307 | }; | |
1308 | ||
444ceed8 | 1309 | static struct dentry *proc_fd_instantiate(struct inode *dir, |
c5141e6d | 1310 | struct dentry *dentry, struct task_struct *task, const void *ptr) |
1da177e4 | 1311 | { |
c5141e6d | 1312 | unsigned fd = *(const unsigned *)ptr; |
444ceed8 EB |
1313 | struct file *file; |
1314 | struct files_struct *files; | |
1315 | struct inode *inode; | |
1316 | struct proc_inode *ei; | |
1317 | struct dentry *error = ERR_PTR(-ENOENT); | |
1da177e4 | 1318 | |
61a28784 | 1319 | inode = proc_pid_make_inode(dir->i_sb, task); |
1da177e4 LT |
1320 | if (!inode) |
1321 | goto out; | |
1322 | ei = PROC_I(inode); | |
aed7a6c4 | 1323 | ei->fd = fd; |
1da177e4 LT |
1324 | files = get_files_struct(task); |
1325 | if (!files) | |
444ceed8 | 1326 | goto out_iput; |
1da177e4 | 1327 | inode->i_mode = S_IFLNK; |
ca99c1da DS |
1328 | |
1329 | /* | |
1330 | * We are not taking a ref to the file structure, so we must | |
1331 | * hold ->file_lock. | |
1332 | */ | |
1333 | spin_lock(&files->file_lock); | |
1da177e4 LT |
1334 | file = fcheck_files(files, fd); |
1335 | if (!file) | |
444ceed8 | 1336 | goto out_unlock; |
1da177e4 LT |
1337 | if (file->f_mode & 1) |
1338 | inode->i_mode |= S_IRUSR | S_IXUSR; | |
1339 | if (file->f_mode & 2) | |
1340 | inode->i_mode |= S_IWUSR | S_IXUSR; | |
ca99c1da | 1341 | spin_unlock(&files->file_lock); |
1da177e4 | 1342 | put_files_struct(files); |
444ceed8 | 1343 | |
1da177e4 LT |
1344 | inode->i_op = &proc_pid_link_inode_operations; |
1345 | inode->i_size = 64; | |
1346 | ei->op.proc_get_link = proc_fd_link; | |
1347 | dentry->d_op = &tid_fd_dentry_operations; | |
1348 | d_add(dentry, inode); | |
cd6a3ce9 EB |
1349 | /* Close the race of the process dying before we return the dentry */ |
1350 | if (tid_fd_revalidate(dentry, NULL)) | |
444ceed8 | 1351 | error = NULL; |
1da177e4 | 1352 | |
444ceed8 EB |
1353 | out: |
1354 | return error; | |
1355 | out_unlock: | |
ca99c1da | 1356 | spin_unlock(&files->file_lock); |
1da177e4 | 1357 | put_files_struct(files); |
444ceed8 | 1358 | out_iput: |
1da177e4 | 1359 | iput(inode); |
cd6a3ce9 | 1360 | goto out; |
1da177e4 LT |
1361 | } |
1362 | ||
27932742 MS |
1363 | static struct dentry *proc_lookupfd_common(struct inode *dir, |
1364 | struct dentry *dentry, | |
1365 | instantiate_t instantiate) | |
444ceed8 EB |
1366 | { |
1367 | struct task_struct *task = get_proc_task(dir); | |
1368 | unsigned fd = name_to_int(dentry); | |
1369 | struct dentry *result = ERR_PTR(-ENOENT); | |
1370 | ||
1371 | if (!task) | |
1372 | goto out_no_task; | |
1373 | if (fd == ~0U) | |
1374 | goto out; | |
1375 | ||
27932742 | 1376 | result = instantiate(dir, dentry, task, &fd); |
444ceed8 EB |
1377 | out: |
1378 | put_task_struct(task); | |
1379 | out_no_task: | |
1380 | return result; | |
1381 | } | |
1382 | ||
27932742 MS |
1383 | static int proc_readfd_common(struct file * filp, void * dirent, |
1384 | filldir_t filldir, instantiate_t instantiate) | |
28a6d671 | 1385 | { |
2fddfeef | 1386 | struct dentry *dentry = filp->f_path.dentry; |
28a6d671 EB |
1387 | struct inode *inode = dentry->d_inode; |
1388 | struct task_struct *p = get_proc_task(inode); | |
1389 | unsigned int fd, tid, ino; | |
1390 | int retval; | |
28a6d671 EB |
1391 | struct files_struct * files; |
1392 | struct fdtable *fdt; | |
1da177e4 | 1393 | |
28a6d671 EB |
1394 | retval = -ENOENT; |
1395 | if (!p) | |
1396 | goto out_no_task; | |
1397 | retval = 0; | |
1398 | tid = p->pid; | |
1399 | ||
1400 | fd = filp->f_pos; | |
1401 | switch (fd) { | |
1402 | case 0: | |
1403 | if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) | |
1404 | goto out; | |
1405 | filp->f_pos++; | |
1406 | case 1: | |
1407 | ino = parent_ino(dentry); | |
1408 | if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) | |
1409 | goto out; | |
1410 | filp->f_pos++; | |
1411 | default: | |
1412 | files = get_files_struct(p); | |
1413 | if (!files) | |
1414 | goto out; | |
1415 | rcu_read_lock(); | |
1416 | fdt = files_fdtable(files); | |
1417 | for (fd = filp->f_pos-2; | |
1418 | fd < fdt->max_fds; | |
1419 | fd++, filp->f_pos++) { | |
27932742 MS |
1420 | char name[PROC_NUMBUF]; |
1421 | int len; | |
28a6d671 EB |
1422 | |
1423 | if (!fcheck_files(files, fd)) | |
1424 | continue; | |
1425 | rcu_read_unlock(); | |
1426 | ||
27932742 MS |
1427 | len = snprintf(name, sizeof(name), "%d", fd); |
1428 | if (proc_fill_cache(filp, dirent, filldir, | |
1429 | name, len, instantiate, | |
1430 | p, &fd) < 0) { | |
28a6d671 EB |
1431 | rcu_read_lock(); |
1432 | break; | |
1433 | } | |
1434 | rcu_read_lock(); | |
1435 | } | |
1436 | rcu_read_unlock(); | |
1437 | put_files_struct(files); | |
1438 | } | |
1439 | out: | |
1440 | put_task_struct(p); | |
1441 | out_no_task: | |
1442 | return retval; | |
1443 | } | |
1444 | ||
27932742 MS |
1445 | static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, |
1446 | struct nameidata *nd) | |
1447 | { | |
1448 | return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); | |
1449 | } | |
1450 | ||
1451 | static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) | |
1452 | { | |
1453 | return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); | |
1454 | } | |
1455 | ||
1456 | static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, | |
1457 | size_t len, loff_t *ppos) | |
1458 | { | |
1459 | char tmp[PROC_FDINFO_MAX]; | |
1460 | int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, NULL, tmp); | |
1461 | if (!err) | |
1462 | err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); | |
1463 | return err; | |
1464 | } | |
1465 | ||
1466 | static const struct file_operations proc_fdinfo_file_operations = { | |
1467 | .open = nonseekable_open, | |
1468 | .read = proc_fdinfo_read, | |
1469 | }; | |
1470 | ||
00977a59 | 1471 | static const struct file_operations proc_fd_operations = { |
28a6d671 EB |
1472 | .read = generic_read_dir, |
1473 | .readdir = proc_readfd, | |
1da177e4 LT |
1474 | }; |
1475 | ||
8948e11f AD |
1476 | /* |
1477 | * /proc/pid/fd needs a special permission handler so that a process can still | |
1478 | * access /proc/self/fd after it has executed a setuid(). | |
1479 | */ | |
1480 | static int proc_fd_permission(struct inode *inode, int mask, | |
1481 | struct nameidata *nd) | |
1482 | { | |
1483 | int rv; | |
1484 | ||
1485 | rv = generic_permission(inode, mask, NULL); | |
1486 | if (rv == 0) | |
1487 | return 0; | |
1488 | if (task_pid(current) == proc_pid(inode)) | |
1489 | rv = 0; | |
1490 | return rv; | |
1491 | } | |
1492 | ||
1da177e4 LT |
1493 | /* |
1494 | * proc directories can do almost nothing.. | |
1495 | */ | |
c5ef1c42 | 1496 | static const struct inode_operations proc_fd_inode_operations = { |
1da177e4 | 1497 | .lookup = proc_lookupfd, |
8948e11f | 1498 | .permission = proc_fd_permission, |
6d76fa58 | 1499 | .setattr = proc_setattr, |
1da177e4 LT |
1500 | }; |
1501 | ||
27932742 MS |
1502 | static struct dentry *proc_fdinfo_instantiate(struct inode *dir, |
1503 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
1504 | { | |
1505 | unsigned fd = *(unsigned *)ptr; | |
1506 | struct inode *inode; | |
1507 | struct proc_inode *ei; | |
1508 | struct dentry *error = ERR_PTR(-ENOENT); | |
1509 | ||
1510 | inode = proc_pid_make_inode(dir->i_sb, task); | |
1511 | if (!inode) | |
1512 | goto out; | |
1513 | ei = PROC_I(inode); | |
1514 | ei->fd = fd; | |
1515 | inode->i_mode = S_IFREG | S_IRUSR; | |
1516 | inode->i_fop = &proc_fdinfo_file_operations; | |
1517 | dentry->d_op = &tid_fd_dentry_operations; | |
1518 | d_add(dentry, inode); | |
1519 | /* Close the race of the process dying before we return the dentry */ | |
1520 | if (tid_fd_revalidate(dentry, NULL)) | |
1521 | error = NULL; | |
1522 | ||
1523 | out: | |
1524 | return error; | |
1525 | } | |
1526 | ||
1527 | static struct dentry *proc_lookupfdinfo(struct inode *dir, | |
1528 | struct dentry *dentry, | |
1529 | struct nameidata *nd) | |
1530 | { | |
1531 | return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); | |
1532 | } | |
1533 | ||
1534 | static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) | |
1535 | { | |
1536 | return proc_readfd_common(filp, dirent, filldir, | |
1537 | proc_fdinfo_instantiate); | |
1538 | } | |
1539 | ||
1540 | static const struct file_operations proc_fdinfo_operations = { | |
1541 | .read = generic_read_dir, | |
1542 | .readdir = proc_readfdinfo, | |
1543 | }; | |
1544 | ||
1545 | /* | |
1546 | * proc directories can do almost nothing.. | |
1547 | */ | |
1548 | static const struct inode_operations proc_fdinfo_inode_operations = { | |
1549 | .lookup = proc_lookupfdinfo, | |
1550 | .setattr = proc_setattr, | |
1551 | }; | |
1552 | ||
1553 | ||
444ceed8 | 1554 | static struct dentry *proc_pident_instantiate(struct inode *dir, |
c5141e6d | 1555 | struct dentry *dentry, struct task_struct *task, const void *ptr) |
444ceed8 | 1556 | { |
c5141e6d | 1557 | const struct pid_entry *p = ptr; |
444ceed8 EB |
1558 | struct inode *inode; |
1559 | struct proc_inode *ei; | |
1560 | struct dentry *error = ERR_PTR(-EINVAL); | |
1561 | ||
61a28784 | 1562 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
1563 | if (!inode) |
1564 | goto out; | |
1565 | ||
1566 | ei = PROC_I(inode); | |
1567 | inode->i_mode = p->mode; | |
1568 | if (S_ISDIR(inode->i_mode)) | |
1569 | inode->i_nlink = 2; /* Use getattr to fix if necessary */ | |
1570 | if (p->iop) | |
1571 | inode->i_op = p->iop; | |
1572 | if (p->fop) | |
1573 | inode->i_fop = p->fop; | |
1574 | ei->op = p->op; | |
1575 | dentry->d_op = &pid_dentry_operations; | |
1576 | d_add(dentry, inode); | |
1577 | /* Close the race of the process dying before we return the dentry */ | |
1578 | if (pid_revalidate(dentry, NULL)) | |
1579 | error = NULL; | |
1580 | out: | |
1581 | return error; | |
1582 | } | |
1583 | ||
1da177e4 LT |
1584 | static struct dentry *proc_pident_lookup(struct inode *dir, |
1585 | struct dentry *dentry, | |
c5141e6d | 1586 | const struct pid_entry *ents, |
7bcd6b0e | 1587 | unsigned int nents) |
1da177e4 LT |
1588 | { |
1589 | struct inode *inode; | |
cd6a3ce9 | 1590 | struct dentry *error; |
99f89551 | 1591 | struct task_struct *task = get_proc_task(dir); |
c5141e6d | 1592 | const struct pid_entry *p, *last; |
1da177e4 | 1593 | |
cd6a3ce9 | 1594 | error = ERR_PTR(-ENOENT); |
1da177e4 LT |
1595 | inode = NULL; |
1596 | ||
99f89551 EB |
1597 | if (!task) |
1598 | goto out_no_task; | |
1da177e4 | 1599 | |
20cdc894 EB |
1600 | /* |
1601 | * Yes, it does not scale. And it should not. Don't add | |
1602 | * new entries into /proc/<tgid>/ without very good reasons. | |
1603 | */ | |
7bcd6b0e EB |
1604 | last = &ents[nents - 1]; |
1605 | for (p = ents; p <= last; p++) { | |
1da177e4 LT |
1606 | if (p->len != dentry->d_name.len) |
1607 | continue; | |
1608 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
1609 | break; | |
1610 | } | |
7bcd6b0e | 1611 | if (p > last) |
1da177e4 LT |
1612 | goto out; |
1613 | ||
444ceed8 | 1614 | error = proc_pident_instantiate(dir, dentry, task, p); |
1da177e4 | 1615 | out: |
99f89551 EB |
1616 | put_task_struct(task); |
1617 | out_no_task: | |
cd6a3ce9 | 1618 | return error; |
1da177e4 LT |
1619 | } |
1620 | ||
c5141e6d ED |
1621 | static int proc_pident_fill_cache(struct file *filp, void *dirent, |
1622 | filldir_t filldir, struct task_struct *task, const struct pid_entry *p) | |
61a28784 EB |
1623 | { |
1624 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
1625 | proc_pident_instantiate, task, p); | |
1626 | } | |
1627 | ||
28a6d671 EB |
1628 | static int proc_pident_readdir(struct file *filp, |
1629 | void *dirent, filldir_t filldir, | |
c5141e6d | 1630 | const struct pid_entry *ents, unsigned int nents) |
28a6d671 EB |
1631 | { |
1632 | int i; | |
1633 | int pid; | |
2fddfeef | 1634 | struct dentry *dentry = filp->f_path.dentry; |
28a6d671 EB |
1635 | struct inode *inode = dentry->d_inode; |
1636 | struct task_struct *task = get_proc_task(inode); | |
c5141e6d | 1637 | const struct pid_entry *p, *last; |
28a6d671 EB |
1638 | ino_t ino; |
1639 | int ret; | |
1640 | ||
1641 | ret = -ENOENT; | |
1642 | if (!task) | |
61a28784 | 1643 | goto out_no_task; |
28a6d671 EB |
1644 | |
1645 | ret = 0; | |
1646 | pid = task->pid; | |
28a6d671 EB |
1647 | i = filp->f_pos; |
1648 | switch (i) { | |
1649 | case 0: | |
1650 | ino = inode->i_ino; | |
1651 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
1652 | goto out; | |
1653 | i++; | |
1654 | filp->f_pos++; | |
1655 | /* fall through */ | |
1656 | case 1: | |
1657 | ino = parent_ino(dentry); | |
1658 | if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) | |
1659 | goto out; | |
1660 | i++; | |
1661 | filp->f_pos++; | |
1662 | /* fall through */ | |
1663 | default: | |
1664 | i -= 2; | |
1665 | if (i >= nents) { | |
1666 | ret = 1; | |
1667 | goto out; | |
1668 | } | |
1669 | p = ents + i; | |
7bcd6b0e EB |
1670 | last = &ents[nents - 1]; |
1671 | while (p <= last) { | |
61a28784 | 1672 | if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) |
28a6d671 EB |
1673 | goto out; |
1674 | filp->f_pos++; | |
1675 | p++; | |
1676 | } | |
1677 | } | |
1678 | ||
1679 | ret = 1; | |
1680 | out: | |
61a28784 EB |
1681 | put_task_struct(task); |
1682 | out_no_task: | |
28a6d671 | 1683 | return ret; |
1da177e4 LT |
1684 | } |
1685 | ||
28a6d671 EB |
1686 | #ifdef CONFIG_SECURITY |
1687 | static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, | |
1688 | size_t count, loff_t *ppos) | |
1689 | { | |
2fddfeef | 1690 | struct inode * inode = file->f_path.dentry->d_inode; |
04ff9708 | 1691 | char *p = NULL; |
28a6d671 EB |
1692 | ssize_t length; |
1693 | struct task_struct *task = get_proc_task(inode); | |
1694 | ||
28a6d671 | 1695 | if (!task) |
04ff9708 | 1696 | return -ESRCH; |
28a6d671 EB |
1697 | |
1698 | length = security_getprocattr(task, | |
2fddfeef | 1699 | (char*)file->f_path.dentry->d_name.name, |
04ff9708 | 1700 | &p); |
28a6d671 | 1701 | put_task_struct(task); |
04ff9708 AV |
1702 | if (length > 0) |
1703 | length = simple_read_from_buffer(buf, count, ppos, p, length); | |
1704 | kfree(p); | |
28a6d671 | 1705 | return length; |
1da177e4 LT |
1706 | } |
1707 | ||
28a6d671 EB |
1708 | static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, |
1709 | size_t count, loff_t *ppos) | |
1710 | { | |
2fddfeef | 1711 | struct inode * inode = file->f_path.dentry->d_inode; |
28a6d671 EB |
1712 | char *page; |
1713 | ssize_t length; | |
1714 | struct task_struct *task = get_proc_task(inode); | |
1715 | ||
1716 | length = -ESRCH; | |
1717 | if (!task) | |
1718 | goto out_no_task; | |
1719 | if (count > PAGE_SIZE) | |
1720 | count = PAGE_SIZE; | |
1721 | ||
1722 | /* No partial writes. */ | |
1723 | length = -EINVAL; | |
1724 | if (*ppos != 0) | |
1725 | goto out; | |
1726 | ||
1727 | length = -ENOMEM; | |
1728 | page = (char*)__get_free_page(GFP_USER); | |
1729 | if (!page) | |
1730 | goto out; | |
1731 | ||
1732 | length = -EFAULT; | |
1733 | if (copy_from_user(page, buf, count)) | |
1734 | goto out_free; | |
1735 | ||
1736 | length = security_setprocattr(task, | |
2fddfeef | 1737 | (char*)file->f_path.dentry->d_name.name, |
28a6d671 EB |
1738 | (void*)page, count); |
1739 | out_free: | |
1740 | free_page((unsigned long) page); | |
1741 | out: | |
1742 | put_task_struct(task); | |
1743 | out_no_task: | |
1744 | return length; | |
1745 | } | |
1746 | ||
00977a59 | 1747 | static const struct file_operations proc_pid_attr_operations = { |
28a6d671 EB |
1748 | .read = proc_pid_attr_read, |
1749 | .write = proc_pid_attr_write, | |
1750 | }; | |
1751 | ||
c5141e6d | 1752 | static const struct pid_entry attr_dir_stuff[] = { |
61a28784 EB |
1753 | REG("current", S_IRUGO|S_IWUGO, pid_attr), |
1754 | REG("prev", S_IRUGO, pid_attr), | |
1755 | REG("exec", S_IRUGO|S_IWUGO, pid_attr), | |
1756 | REG("fscreate", S_IRUGO|S_IWUGO, pid_attr), | |
1757 | REG("keycreate", S_IRUGO|S_IWUGO, pid_attr), | |
1758 | REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr), | |
28a6d671 EB |
1759 | }; |
1760 | ||
72d9dcfc | 1761 | static int proc_attr_dir_readdir(struct file * filp, |
28a6d671 EB |
1762 | void * dirent, filldir_t filldir) |
1763 | { | |
1764 | return proc_pident_readdir(filp,dirent,filldir, | |
72d9dcfc | 1765 | attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); |
28a6d671 EB |
1766 | } |
1767 | ||
00977a59 | 1768 | static const struct file_operations proc_attr_dir_operations = { |
1da177e4 | 1769 | .read = generic_read_dir, |
72d9dcfc | 1770 | .readdir = proc_attr_dir_readdir, |
1da177e4 LT |
1771 | }; |
1772 | ||
72d9dcfc | 1773 | static struct dentry *proc_attr_dir_lookup(struct inode *dir, |
28a6d671 EB |
1774 | struct dentry *dentry, struct nameidata *nd) |
1775 | { | |
7bcd6b0e EB |
1776 | return proc_pident_lookup(dir, dentry, |
1777 | attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); | |
28a6d671 EB |
1778 | } |
1779 | ||
c5ef1c42 | 1780 | static const struct inode_operations proc_attr_dir_inode_operations = { |
72d9dcfc | 1781 | .lookup = proc_attr_dir_lookup, |
99f89551 | 1782 | .getattr = pid_getattr, |
6d76fa58 | 1783 | .setattr = proc_setattr, |
1da177e4 LT |
1784 | }; |
1785 | ||
28a6d671 EB |
1786 | #endif |
1787 | ||
1788 | /* | |
1789 | * /proc/self: | |
1790 | */ | |
1791 | static int proc_self_readlink(struct dentry *dentry, char __user *buffer, | |
1792 | int buflen) | |
1793 | { | |
1794 | char tmp[PROC_NUMBUF]; | |
1795 | sprintf(tmp, "%d", current->tgid); | |
1796 | return vfs_readlink(dentry,buffer,buflen,tmp); | |
1797 | } | |
1798 | ||
1799 | static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) | |
1800 | { | |
1801 | char tmp[PROC_NUMBUF]; | |
1802 | sprintf(tmp, "%d", current->tgid); | |
1803 | return ERR_PTR(vfs_follow_link(nd,tmp)); | |
1804 | } | |
1805 | ||
c5ef1c42 | 1806 | static const struct inode_operations proc_self_inode_operations = { |
28a6d671 EB |
1807 | .readlink = proc_self_readlink, |
1808 | .follow_link = proc_self_follow_link, | |
1809 | }; | |
1810 | ||
801199ce EB |
1811 | /* |
1812 | * proc base | |
1813 | * | |
1814 | * These are the directory entries in the root directory of /proc | |
1815 | * that properly belong to the /proc filesystem, as they describe | |
1816 | * describe something that is process related. | |
1817 | */ | |
c5141e6d | 1818 | static const struct pid_entry proc_base_stuff[] = { |
61a28784 | 1819 | NOD("self", S_IFLNK|S_IRWXUGO, |
801199ce | 1820 | &proc_self_inode_operations, NULL, {}), |
801199ce EB |
1821 | }; |
1822 | ||
1823 | /* | |
1824 | * Exceptional case: normally we are not allowed to unhash a busy | |
1825 | * directory. In this case, however, we can do it - no aliasing problems | |
1826 | * due to the way we treat inodes. | |
1827 | */ | |
1828 | static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1829 | { | |
1830 | struct inode *inode = dentry->d_inode; | |
1831 | struct task_struct *task = get_proc_task(inode); | |
1832 | if (task) { | |
1833 | put_task_struct(task); | |
1834 | return 1; | |
1835 | } | |
1836 | d_drop(dentry); | |
1837 | return 0; | |
1838 | } | |
1839 | ||
1840 | static struct dentry_operations proc_base_dentry_operations = | |
1841 | { | |
1842 | .d_revalidate = proc_base_revalidate, | |
1843 | .d_delete = pid_delete_dentry, | |
1844 | }; | |
1845 | ||
444ceed8 | 1846 | static struct dentry *proc_base_instantiate(struct inode *dir, |
c5141e6d | 1847 | struct dentry *dentry, struct task_struct *task, const void *ptr) |
801199ce | 1848 | { |
c5141e6d | 1849 | const struct pid_entry *p = ptr; |
801199ce | 1850 | struct inode *inode; |
801199ce | 1851 | struct proc_inode *ei; |
444ceed8 | 1852 | struct dentry *error = ERR_PTR(-EINVAL); |
801199ce EB |
1853 | |
1854 | /* Allocate the inode */ | |
1855 | error = ERR_PTR(-ENOMEM); | |
1856 | inode = new_inode(dir->i_sb); | |
1857 | if (!inode) | |
1858 | goto out; | |
1859 | ||
1860 | /* Initialize the inode */ | |
1861 | ei = PROC_I(inode); | |
1862 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
801199ce EB |
1863 | |
1864 | /* | |
1865 | * grab the reference to the task. | |
1866 | */ | |
1a657f78 | 1867 | ei->pid = get_task_pid(task, PIDTYPE_PID); |
801199ce EB |
1868 | if (!ei->pid) |
1869 | goto out_iput; | |
1870 | ||
1871 | inode->i_uid = 0; | |
1872 | inode->i_gid = 0; | |
1873 | inode->i_mode = p->mode; | |
1874 | if (S_ISDIR(inode->i_mode)) | |
1875 | inode->i_nlink = 2; | |
1876 | if (S_ISLNK(inode->i_mode)) | |
1877 | inode->i_size = 64; | |
1878 | if (p->iop) | |
1879 | inode->i_op = p->iop; | |
1880 | if (p->fop) | |
1881 | inode->i_fop = p->fop; | |
1882 | ei->op = p->op; | |
1883 | dentry->d_op = &proc_base_dentry_operations; | |
1884 | d_add(dentry, inode); | |
1885 | error = NULL; | |
1886 | out: | |
801199ce EB |
1887 | return error; |
1888 | out_iput: | |
1889 | iput(inode); | |
1890 | goto out; | |
1891 | } | |
1892 | ||
444ceed8 EB |
1893 | static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) |
1894 | { | |
1895 | struct dentry *error; | |
1896 | struct task_struct *task = get_proc_task(dir); | |
c5141e6d | 1897 | const struct pid_entry *p, *last; |
444ceed8 EB |
1898 | |
1899 | error = ERR_PTR(-ENOENT); | |
1900 | ||
1901 | if (!task) | |
1902 | goto out_no_task; | |
1903 | ||
1904 | /* Lookup the directory entry */ | |
7bcd6b0e EB |
1905 | last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; |
1906 | for (p = proc_base_stuff; p <= last; p++) { | |
444ceed8 EB |
1907 | if (p->len != dentry->d_name.len) |
1908 | continue; | |
1909 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
1910 | break; | |
1911 | } | |
7bcd6b0e | 1912 | if (p > last) |
444ceed8 EB |
1913 | goto out; |
1914 | ||
1915 | error = proc_base_instantiate(dir, dentry, task, p); | |
1916 | ||
1917 | out: | |
1918 | put_task_struct(task); | |
1919 | out_no_task: | |
1920 | return error; | |
1921 | } | |
1922 | ||
c5141e6d ED |
1923 | static int proc_base_fill_cache(struct file *filp, void *dirent, |
1924 | filldir_t filldir, struct task_struct *task, const struct pid_entry *p) | |
61a28784 EB |
1925 | { |
1926 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
1927 | proc_base_instantiate, task, p); | |
1928 | } | |
1929 | ||
aba76fdb AM |
1930 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
1931 | static int proc_pid_io_accounting(struct task_struct *task, char *buffer) | |
1932 | { | |
1933 | return sprintf(buffer, | |
4b98d11b | 1934 | #ifdef CONFIG_TASK_XACCT |
aba76fdb AM |
1935 | "rchar: %llu\n" |
1936 | "wchar: %llu\n" | |
1937 | "syscr: %llu\n" | |
1938 | "syscw: %llu\n" | |
4b98d11b | 1939 | #endif |
aba76fdb AM |
1940 | "read_bytes: %llu\n" |
1941 | "write_bytes: %llu\n" | |
1942 | "cancelled_write_bytes: %llu\n", | |
4b98d11b | 1943 | #ifdef CONFIG_TASK_XACCT |
aba76fdb AM |
1944 | (unsigned long long)task->rchar, |
1945 | (unsigned long long)task->wchar, | |
1946 | (unsigned long long)task->syscr, | |
1947 | (unsigned long long)task->syscw, | |
4b98d11b | 1948 | #endif |
aba76fdb AM |
1949 | (unsigned long long)task->ioac.read_bytes, |
1950 | (unsigned long long)task->ioac.write_bytes, | |
1951 | (unsigned long long)task->ioac.cancelled_write_bytes); | |
1952 | } | |
1953 | #endif | |
1954 | ||
28a6d671 EB |
1955 | /* |
1956 | * Thread groups | |
1957 | */ | |
00977a59 | 1958 | static const struct file_operations proc_task_operations; |
c5ef1c42 | 1959 | static const struct inode_operations proc_task_inode_operations; |
20cdc894 | 1960 | |
c5141e6d | 1961 | static const struct pid_entry tgid_base_stuff[] = { |
61a28784 EB |
1962 | DIR("task", S_IRUGO|S_IXUGO, task), |
1963 | DIR("fd", S_IRUSR|S_IXUSR, fd), | |
27932742 | 1964 | DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), |
61a28784 EB |
1965 | INF("environ", S_IRUSR, pid_environ), |
1966 | INF("auxv", S_IRUSR, pid_auxv), | |
1967 | INF("status", S_IRUGO, pid_status), | |
43ae34cb IM |
1968 | #ifdef CONFIG_SCHED_DEBUG |
1969 | REG("sched", S_IRUGO|S_IWUSR, pid_sched), | |
1970 | #endif | |
61a28784 EB |
1971 | INF("cmdline", S_IRUGO, pid_cmdline), |
1972 | INF("stat", S_IRUGO, tgid_stat), | |
1973 | INF("statm", S_IRUGO, pid_statm), | |
1974 | REG("maps", S_IRUGO, maps), | |
28a6d671 | 1975 | #ifdef CONFIG_NUMA |
61a28784 | 1976 | REG("numa_maps", S_IRUGO, numa_maps), |
28a6d671 | 1977 | #endif |
61a28784 | 1978 | REG("mem", S_IRUSR|S_IWUSR, mem), |
61a28784 EB |
1979 | LNK("cwd", cwd), |
1980 | LNK("root", root), | |
1981 | LNK("exe", exe), | |
1982 | REG("mounts", S_IRUGO, mounts), | |
1983 | REG("mountstats", S_IRUSR, mountstats), | |
28a6d671 | 1984 | #ifdef CONFIG_MMU |
b813e931 | 1985 | REG("clear_refs", S_IWUSR, clear_refs), |
61a28784 | 1986 | REG("smaps", S_IRUGO, smaps), |
28a6d671 EB |
1987 | #endif |
1988 | #ifdef CONFIG_SECURITY | |
72d9dcfc | 1989 | DIR("attr", S_IRUGO|S_IXUGO, attr_dir), |
28a6d671 EB |
1990 | #endif |
1991 | #ifdef CONFIG_KALLSYMS | |
61a28784 | 1992 | INF("wchan", S_IRUGO, pid_wchan), |
28a6d671 EB |
1993 | #endif |
1994 | #ifdef CONFIG_SCHEDSTATS | |
61a28784 | 1995 | INF("schedstat", S_IRUGO, pid_schedstat), |
28a6d671 EB |
1996 | #endif |
1997 | #ifdef CONFIG_CPUSETS | |
61a28784 | 1998 | REG("cpuset", S_IRUGO, cpuset), |
28a6d671 | 1999 | #endif |
61a28784 EB |
2000 | INF("oom_score", S_IRUGO, oom_score), |
2001 | REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), | |
28a6d671 | 2002 | #ifdef CONFIG_AUDITSYSCALL |
61a28784 | 2003 | REG("loginuid", S_IWUSR|S_IRUGO, loginuid), |
28a6d671 | 2004 | #endif |
f4f154fd AM |
2005 | #ifdef CONFIG_FAULT_INJECTION |
2006 | REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject), | |
2007 | #endif | |
aba76fdb AM |
2008 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
2009 | INF("io", S_IRUGO, pid_io_accounting), | |
2010 | #endif | |
28a6d671 | 2011 | }; |
1da177e4 | 2012 | |
28a6d671 | 2013 | static int proc_tgid_base_readdir(struct file * filp, |
1da177e4 LT |
2014 | void * dirent, filldir_t filldir) |
2015 | { | |
2016 | return proc_pident_readdir(filp,dirent,filldir, | |
28a6d671 | 2017 | tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); |
1da177e4 LT |
2018 | } |
2019 | ||
00977a59 | 2020 | static const struct file_operations proc_tgid_base_operations = { |
1da177e4 | 2021 | .read = generic_read_dir, |
28a6d671 | 2022 | .readdir = proc_tgid_base_readdir, |
1da177e4 LT |
2023 | }; |
2024 | ||
28a6d671 | 2025 | static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ |
7bcd6b0e EB |
2026 | return proc_pident_lookup(dir, dentry, |
2027 | tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); | |
1da177e4 LT |
2028 | } |
2029 | ||
c5ef1c42 | 2030 | static const struct inode_operations proc_tgid_base_inode_operations = { |
28a6d671 | 2031 | .lookup = proc_tgid_base_lookup, |
99f89551 | 2032 | .getattr = pid_getattr, |
6d76fa58 | 2033 | .setattr = proc_setattr, |
1da177e4 | 2034 | }; |
1da177e4 LT |
2035 | |
2036 | /** | |
48e6484d EB |
2037 | * proc_flush_task - Remove dcache entries for @task from the /proc dcache. |
2038 | * | |
2039 | * @task: task that should be flushed. | |
2040 | * | |
2041 | * Looks in the dcache for | |
2042 | * /proc/@pid | |
2043 | * /proc/@tgid/task/@pid | |
2044 | * if either directory is present flushes it and all of it'ts children | |
2045 | * from the dcache. | |
1da177e4 | 2046 | * |
48e6484d EB |
2047 | * It is safe and reasonable to cache /proc entries for a task until |
2048 | * that task exits. After that they just clog up the dcache with | |
2049 | * useless entries, possibly causing useful dcache entries to be | |
2050 | * flushed instead. This routine is proved to flush those useless | |
2051 | * dcache entries at process exit time. | |
1da177e4 | 2052 | * |
48e6484d EB |
2053 | * NOTE: This routine is just an optimization so it does not guarantee |
2054 | * that no dcache entries will exist at process exit time it | |
2055 | * just makes it very unlikely that any will persist. | |
1da177e4 | 2056 | */ |
48e6484d | 2057 | void proc_flush_task(struct task_struct *task) |
1da177e4 | 2058 | { |
48e6484d | 2059 | struct dentry *dentry, *leader, *dir; |
8578cea7 | 2060 | char buf[PROC_NUMBUF]; |
48e6484d EB |
2061 | struct qstr name; |
2062 | ||
2063 | name.name = buf; | |
2064 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
2065 | dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
2066 | if (dentry) { | |
2067 | shrink_dcache_parent(dentry); | |
2068 | d_drop(dentry); | |
2069 | dput(dentry); | |
2070 | } | |
1da177e4 | 2071 | |
48e6484d EB |
2072 | if (thread_group_leader(task)) |
2073 | goto out; | |
1da177e4 | 2074 | |
48e6484d EB |
2075 | name.name = buf; |
2076 | name.len = snprintf(buf, sizeof(buf), "%d", task->tgid); | |
2077 | leader = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
2078 | if (!leader) | |
2079 | goto out; | |
1da177e4 | 2080 | |
48e6484d EB |
2081 | name.name = "task"; |
2082 | name.len = strlen(name.name); | |
2083 | dir = d_hash_and_lookup(leader, &name); | |
2084 | if (!dir) | |
2085 | goto out_put_leader; | |
2086 | ||
2087 | name.name = buf; | |
2088 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
2089 | dentry = d_hash_and_lookup(dir, &name); | |
2090 | if (dentry) { | |
2091 | shrink_dcache_parent(dentry); | |
2092 | d_drop(dentry); | |
2093 | dput(dentry); | |
1da177e4 | 2094 | } |
48e6484d EB |
2095 | |
2096 | dput(dir); | |
2097 | out_put_leader: | |
2098 | dput(leader); | |
2099 | out: | |
2100 | return; | |
1da177e4 LT |
2101 | } |
2102 | ||
9711ef99 AB |
2103 | static struct dentry *proc_pid_instantiate(struct inode *dir, |
2104 | struct dentry * dentry, | |
c5141e6d | 2105 | struct task_struct *task, const void *ptr) |
444ceed8 EB |
2106 | { |
2107 | struct dentry *error = ERR_PTR(-ENOENT); | |
2108 | struct inode *inode; | |
2109 | ||
61a28784 | 2110 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
2111 | if (!inode) |
2112 | goto out; | |
2113 | ||
2114 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2115 | inode->i_op = &proc_tgid_base_inode_operations; | |
2116 | inode->i_fop = &proc_tgid_base_operations; | |
2117 | inode->i_flags|=S_IMMUTABLE; | |
27932742 | 2118 | inode->i_nlink = 5; |
444ceed8 EB |
2119 | #ifdef CONFIG_SECURITY |
2120 | inode->i_nlink += 1; | |
2121 | #endif | |
2122 | ||
2123 | dentry->d_op = &pid_dentry_operations; | |
2124 | ||
2125 | d_add(dentry, inode); | |
2126 | /* Close the race of the process dying before we return the dentry */ | |
2127 | if (pid_revalidate(dentry, NULL)) | |
2128 | error = NULL; | |
2129 | out: | |
2130 | return error; | |
2131 | } | |
2132 | ||
1da177e4 LT |
2133 | struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) |
2134 | { | |
cd6a3ce9 | 2135 | struct dentry *result = ERR_PTR(-ENOENT); |
1da177e4 | 2136 | struct task_struct *task; |
1da177e4 | 2137 | unsigned tgid; |
1da177e4 | 2138 | |
801199ce EB |
2139 | result = proc_base_lookup(dir, dentry); |
2140 | if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) | |
2141 | goto out; | |
2142 | ||
1da177e4 LT |
2143 | tgid = name_to_int(dentry); |
2144 | if (tgid == ~0U) | |
2145 | goto out; | |
2146 | ||
de758734 | 2147 | rcu_read_lock(); |
1da177e4 LT |
2148 | task = find_task_by_pid(tgid); |
2149 | if (task) | |
2150 | get_task_struct(task); | |
de758734 | 2151 | rcu_read_unlock(); |
1da177e4 LT |
2152 | if (!task) |
2153 | goto out; | |
2154 | ||
444ceed8 | 2155 | result = proc_pid_instantiate(dir, dentry, task, NULL); |
1da177e4 | 2156 | put_task_struct(task); |
1da177e4 | 2157 | out: |
cd6a3ce9 | 2158 | return result; |
1da177e4 LT |
2159 | } |
2160 | ||
1da177e4 | 2161 | /* |
0804ef4b | 2162 | * Find the first task with tgid >= tgid |
0bc58a91 | 2163 | * |
1da177e4 | 2164 | */ |
0804ef4b | 2165 | static struct task_struct *next_tgid(unsigned int tgid) |
1da177e4 | 2166 | { |
0804ef4b EB |
2167 | struct task_struct *task; |
2168 | struct pid *pid; | |
1da177e4 | 2169 | |
454cc105 | 2170 | rcu_read_lock(); |
0804ef4b EB |
2171 | retry: |
2172 | task = NULL; | |
2173 | pid = find_ge_pid(tgid); | |
2174 | if (pid) { | |
2175 | tgid = pid->nr + 1; | |
2176 | task = pid_task(pid, PIDTYPE_PID); | |
2177 | /* What we to know is if the pid we have find is the | |
2178 | * pid of a thread_group_leader. Testing for task | |
2179 | * being a thread_group_leader is the obvious thing | |
2180 | * todo but there is a window when it fails, due to | |
2181 | * the pid transfer logic in de_thread. | |
2182 | * | |
2183 | * So we perform the straight forward test of seeing | |
2184 | * if the pid we have found is the pid of a thread | |
2185 | * group leader, and don't worry if the task we have | |
2186 | * found doesn't happen to be a thread group leader. | |
2187 | * As we don't care in the case of readdir. | |
2188 | */ | |
2189 | if (!task || !has_group_leader_pid(task)) | |
2190 | goto retry; | |
2191 | get_task_struct(task); | |
0bc58a91 | 2192 | } |
454cc105 | 2193 | rcu_read_unlock(); |
0804ef4b | 2194 | return task; |
1da177e4 LT |
2195 | } |
2196 | ||
7bcd6b0e | 2197 | #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) |
0804ef4b | 2198 | |
61a28784 EB |
2199 | static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
2200 | struct task_struct *task, int tgid) | |
2201 | { | |
2202 | char name[PROC_NUMBUF]; | |
2203 | int len = snprintf(name, sizeof(name), "%d", tgid); | |
2204 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
2205 | proc_pid_instantiate, task, NULL); | |
2206 | } | |
2207 | ||
1da177e4 LT |
2208 | /* for the /proc/ directory itself, after non-process stuff has been done */ |
2209 | int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2210 | { | |
1da177e4 | 2211 | unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; |
2fddfeef | 2212 | struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); |
0bc58a91 EB |
2213 | struct task_struct *task; |
2214 | int tgid; | |
1da177e4 | 2215 | |
61a28784 EB |
2216 | if (!reaper) |
2217 | goto out_no_task; | |
2218 | ||
7bcd6b0e | 2219 | for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { |
c5141e6d | 2220 | const struct pid_entry *p = &proc_base_stuff[nr]; |
61a28784 | 2221 | if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) |
801199ce | 2222 | goto out; |
1da177e4 LT |
2223 | } |
2224 | ||
0804ef4b EB |
2225 | tgid = filp->f_pos - TGID_OFFSET; |
2226 | for (task = next_tgid(tgid); | |
0bc58a91 | 2227 | task; |
0804ef4b | 2228 | put_task_struct(task), task = next_tgid(tgid + 1)) { |
0bc58a91 | 2229 | tgid = task->pid; |
0804ef4b | 2230 | filp->f_pos = tgid + TGID_OFFSET; |
61a28784 | 2231 | if (proc_pid_fill_cache(filp, dirent, filldir, task, tgid) < 0) { |
0bc58a91 | 2232 | put_task_struct(task); |
0804ef4b | 2233 | goto out; |
1da177e4 | 2234 | } |
0bc58a91 | 2235 | } |
0804ef4b EB |
2236 | filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; |
2237 | out: | |
61a28784 EB |
2238 | put_task_struct(reaper); |
2239 | out_no_task: | |
0bc58a91 EB |
2240 | return 0; |
2241 | } | |
1da177e4 | 2242 | |
28a6d671 EB |
2243 | /* |
2244 | * Tasks | |
2245 | */ | |
c5141e6d | 2246 | static const struct pid_entry tid_base_stuff[] = { |
61a28784 | 2247 | DIR("fd", S_IRUSR|S_IXUSR, fd), |
27932742 | 2248 | DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), |
61a28784 EB |
2249 | INF("environ", S_IRUSR, pid_environ), |
2250 | INF("auxv", S_IRUSR, pid_auxv), | |
2251 | INF("status", S_IRUGO, pid_status), | |
43ae34cb IM |
2252 | #ifdef CONFIG_SCHED_DEBUG |
2253 | REG("sched", S_IRUGO|S_IWUSR, pid_sched), | |
2254 | #endif | |
61a28784 EB |
2255 | INF("cmdline", S_IRUGO, pid_cmdline), |
2256 | INF("stat", S_IRUGO, tid_stat), | |
2257 | INF("statm", S_IRUGO, pid_statm), | |
2258 | REG("maps", S_IRUGO, maps), | |
28a6d671 | 2259 | #ifdef CONFIG_NUMA |
61a28784 | 2260 | REG("numa_maps", S_IRUGO, numa_maps), |
28a6d671 | 2261 | #endif |
61a28784 | 2262 | REG("mem", S_IRUSR|S_IWUSR, mem), |
61a28784 EB |
2263 | LNK("cwd", cwd), |
2264 | LNK("root", root), | |
2265 | LNK("exe", exe), | |
2266 | REG("mounts", S_IRUGO, mounts), | |
28a6d671 | 2267 | #ifdef CONFIG_MMU |
b813e931 | 2268 | REG("clear_refs", S_IWUSR, clear_refs), |
61a28784 | 2269 | REG("smaps", S_IRUGO, smaps), |
28a6d671 EB |
2270 | #endif |
2271 | #ifdef CONFIG_SECURITY | |
72d9dcfc | 2272 | DIR("attr", S_IRUGO|S_IXUGO, attr_dir), |
28a6d671 EB |
2273 | #endif |
2274 | #ifdef CONFIG_KALLSYMS | |
61a28784 | 2275 | INF("wchan", S_IRUGO, pid_wchan), |
28a6d671 EB |
2276 | #endif |
2277 | #ifdef CONFIG_SCHEDSTATS | |
61a28784 | 2278 | INF("schedstat", S_IRUGO, pid_schedstat), |
28a6d671 EB |
2279 | #endif |
2280 | #ifdef CONFIG_CPUSETS | |
61a28784 | 2281 | REG("cpuset", S_IRUGO, cpuset), |
28a6d671 | 2282 | #endif |
61a28784 EB |
2283 | INF("oom_score", S_IRUGO, oom_score), |
2284 | REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), | |
28a6d671 | 2285 | #ifdef CONFIG_AUDITSYSCALL |
61a28784 | 2286 | REG("loginuid", S_IWUSR|S_IRUGO, loginuid), |
28a6d671 | 2287 | #endif |
f4f154fd AM |
2288 | #ifdef CONFIG_FAULT_INJECTION |
2289 | REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject), | |
2290 | #endif | |
28a6d671 EB |
2291 | }; |
2292 | ||
2293 | static int proc_tid_base_readdir(struct file * filp, | |
2294 | void * dirent, filldir_t filldir) | |
2295 | { | |
2296 | return proc_pident_readdir(filp,dirent,filldir, | |
2297 | tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); | |
2298 | } | |
2299 | ||
2300 | static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
7bcd6b0e EB |
2301 | return proc_pident_lookup(dir, dentry, |
2302 | tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); | |
28a6d671 EB |
2303 | } |
2304 | ||
00977a59 | 2305 | static const struct file_operations proc_tid_base_operations = { |
28a6d671 EB |
2306 | .read = generic_read_dir, |
2307 | .readdir = proc_tid_base_readdir, | |
2308 | }; | |
2309 | ||
c5ef1c42 | 2310 | static const struct inode_operations proc_tid_base_inode_operations = { |
28a6d671 EB |
2311 | .lookup = proc_tid_base_lookup, |
2312 | .getattr = pid_getattr, | |
2313 | .setattr = proc_setattr, | |
2314 | }; | |
2315 | ||
444ceed8 | 2316 | static struct dentry *proc_task_instantiate(struct inode *dir, |
c5141e6d | 2317 | struct dentry *dentry, struct task_struct *task, const void *ptr) |
444ceed8 EB |
2318 | { |
2319 | struct dentry *error = ERR_PTR(-ENOENT); | |
2320 | struct inode *inode; | |
61a28784 | 2321 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
2322 | |
2323 | if (!inode) | |
2324 | goto out; | |
2325 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2326 | inode->i_op = &proc_tid_base_inode_operations; | |
2327 | inode->i_fop = &proc_tid_base_operations; | |
2328 | inode->i_flags|=S_IMMUTABLE; | |
27932742 | 2329 | inode->i_nlink = 4; |
444ceed8 EB |
2330 | #ifdef CONFIG_SECURITY |
2331 | inode->i_nlink += 1; | |
2332 | #endif | |
2333 | ||
2334 | dentry->d_op = &pid_dentry_operations; | |
2335 | ||
2336 | d_add(dentry, inode); | |
2337 | /* Close the race of the process dying before we return the dentry */ | |
2338 | if (pid_revalidate(dentry, NULL)) | |
2339 | error = NULL; | |
2340 | out: | |
2341 | return error; | |
2342 | } | |
2343 | ||
28a6d671 EB |
2344 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) |
2345 | { | |
2346 | struct dentry *result = ERR_PTR(-ENOENT); | |
2347 | struct task_struct *task; | |
2348 | struct task_struct *leader = get_proc_task(dir); | |
28a6d671 EB |
2349 | unsigned tid; |
2350 | ||
2351 | if (!leader) | |
2352 | goto out_no_task; | |
2353 | ||
2354 | tid = name_to_int(dentry); | |
2355 | if (tid == ~0U) | |
2356 | goto out; | |
2357 | ||
2358 | rcu_read_lock(); | |
2359 | task = find_task_by_pid(tid); | |
2360 | if (task) | |
2361 | get_task_struct(task); | |
2362 | rcu_read_unlock(); | |
2363 | if (!task) | |
2364 | goto out; | |
2365 | if (leader->tgid != task->tgid) | |
2366 | goto out_drop_task; | |
2367 | ||
444ceed8 | 2368 | result = proc_task_instantiate(dir, dentry, task, NULL); |
28a6d671 EB |
2369 | out_drop_task: |
2370 | put_task_struct(task); | |
2371 | out: | |
2372 | put_task_struct(leader); | |
2373 | out_no_task: | |
2374 | return result; | |
2375 | } | |
2376 | ||
0bc58a91 EB |
2377 | /* |
2378 | * Find the first tid of a thread group to return to user space. | |
2379 | * | |
2380 | * Usually this is just the thread group leader, but if the users | |
2381 | * buffer was too small or there was a seek into the middle of the | |
2382 | * directory we have more work todo. | |
2383 | * | |
2384 | * In the case of a short read we start with find_task_by_pid. | |
2385 | * | |
2386 | * In the case of a seek we start with the leader and walk nr | |
2387 | * threads past it. | |
2388 | */ | |
cc288738 EB |
2389 | static struct task_struct *first_tid(struct task_struct *leader, |
2390 | int tid, int nr) | |
0bc58a91 | 2391 | { |
a872ff0c | 2392 | struct task_struct *pos; |
1da177e4 | 2393 | |
cc288738 | 2394 | rcu_read_lock(); |
0bc58a91 EB |
2395 | /* Attempt to start with the pid of a thread */ |
2396 | if (tid && (nr > 0)) { | |
2397 | pos = find_task_by_pid(tid); | |
a872ff0c ON |
2398 | if (pos && (pos->group_leader == leader)) |
2399 | goto found; | |
0bc58a91 | 2400 | } |
1da177e4 | 2401 | |
0bc58a91 | 2402 | /* If nr exceeds the number of threads there is nothing todo */ |
a872ff0c ON |
2403 | pos = NULL; |
2404 | if (nr && nr >= get_nr_threads(leader)) | |
2405 | goto out; | |
1da177e4 | 2406 | |
a872ff0c ON |
2407 | /* If we haven't found our starting place yet start |
2408 | * with the leader and walk nr threads forward. | |
0bc58a91 | 2409 | */ |
a872ff0c ON |
2410 | for (pos = leader; nr > 0; --nr) { |
2411 | pos = next_thread(pos); | |
2412 | if (pos == leader) { | |
2413 | pos = NULL; | |
2414 | goto out; | |
2415 | } | |
1da177e4 | 2416 | } |
a872ff0c ON |
2417 | found: |
2418 | get_task_struct(pos); | |
2419 | out: | |
cc288738 | 2420 | rcu_read_unlock(); |
0bc58a91 EB |
2421 | return pos; |
2422 | } | |
2423 | ||
2424 | /* | |
2425 | * Find the next thread in the thread list. | |
2426 | * Return NULL if there is an error or no next thread. | |
2427 | * | |
2428 | * The reference to the input task_struct is released. | |
2429 | */ | |
2430 | static struct task_struct *next_tid(struct task_struct *start) | |
2431 | { | |
c1df7fb8 | 2432 | struct task_struct *pos = NULL; |
cc288738 | 2433 | rcu_read_lock(); |
c1df7fb8 | 2434 | if (pid_alive(start)) { |
0bc58a91 | 2435 | pos = next_thread(start); |
c1df7fb8 ON |
2436 | if (thread_group_leader(pos)) |
2437 | pos = NULL; | |
2438 | else | |
2439 | get_task_struct(pos); | |
2440 | } | |
cc288738 | 2441 | rcu_read_unlock(); |
0bc58a91 EB |
2442 | put_task_struct(start); |
2443 | return pos; | |
1da177e4 LT |
2444 | } |
2445 | ||
61a28784 EB |
2446 | static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
2447 | struct task_struct *task, int tid) | |
2448 | { | |
2449 | char name[PROC_NUMBUF]; | |
2450 | int len = snprintf(name, sizeof(name), "%d", tid); | |
2451 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
2452 | proc_task_instantiate, task, NULL); | |
2453 | } | |
2454 | ||
1da177e4 LT |
2455 | /* for the /proc/TGID/task/ directories */ |
2456 | static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2457 | { | |
2fddfeef | 2458 | struct dentry *dentry = filp->f_path.dentry; |
1da177e4 | 2459 | struct inode *inode = dentry->d_inode; |
7d895244 | 2460 | struct task_struct *leader = NULL; |
0bc58a91 | 2461 | struct task_struct *task; |
1da177e4 LT |
2462 | int retval = -ENOENT; |
2463 | ino_t ino; | |
0bc58a91 | 2464 | int tid; |
1da177e4 LT |
2465 | unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ |
2466 | ||
7d895244 GC |
2467 | task = get_proc_task(inode); |
2468 | if (!task) | |
2469 | goto out_no_task; | |
2470 | rcu_read_lock(); | |
2471 | if (pid_alive(task)) { | |
2472 | leader = task->group_leader; | |
2473 | get_task_struct(leader); | |
2474 | } | |
2475 | rcu_read_unlock(); | |
2476 | put_task_struct(task); | |
99f89551 EB |
2477 | if (!leader) |
2478 | goto out_no_task; | |
1da177e4 LT |
2479 | retval = 0; |
2480 | ||
2481 | switch (pos) { | |
2482 | case 0: | |
2483 | ino = inode->i_ino; | |
2484 | if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) | |
2485 | goto out; | |
2486 | pos++; | |
2487 | /* fall through */ | |
2488 | case 1: | |
2489 | ino = parent_ino(dentry); | |
2490 | if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) | |
2491 | goto out; | |
2492 | pos++; | |
2493 | /* fall through */ | |
2494 | } | |
2495 | ||
0bc58a91 EB |
2496 | /* f_version caches the tgid value that the last readdir call couldn't |
2497 | * return. lseek aka telldir automagically resets f_version to 0. | |
2498 | */ | |
2499 | tid = filp->f_version; | |
2500 | filp->f_version = 0; | |
2501 | for (task = first_tid(leader, tid, pos - 2); | |
2502 | task; | |
2503 | task = next_tid(task), pos++) { | |
0bc58a91 | 2504 | tid = task->pid; |
61a28784 | 2505 | if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { |
0bc58a91 EB |
2506 | /* returning this tgid failed, save it as the first |
2507 | * pid for the next readir call */ | |
2508 | filp->f_version = tid; | |
2509 | put_task_struct(task); | |
1da177e4 | 2510 | break; |
0bc58a91 | 2511 | } |
1da177e4 LT |
2512 | } |
2513 | out: | |
2514 | filp->f_pos = pos; | |
99f89551 EB |
2515 | put_task_struct(leader); |
2516 | out_no_task: | |
1da177e4 LT |
2517 | return retval; |
2518 | } | |
6e66b52b EB |
2519 | |
2520 | static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
2521 | { | |
2522 | struct inode *inode = dentry->d_inode; | |
99f89551 | 2523 | struct task_struct *p = get_proc_task(inode); |
6e66b52b EB |
2524 | generic_fillattr(inode, stat); |
2525 | ||
99f89551 EB |
2526 | if (p) { |
2527 | rcu_read_lock(); | |
2528 | stat->nlink += get_nr_threads(p); | |
2529 | rcu_read_unlock(); | |
2530 | put_task_struct(p); | |
6e66b52b EB |
2531 | } |
2532 | ||
2533 | return 0; | |
2534 | } | |
28a6d671 | 2535 | |
c5ef1c42 | 2536 | static const struct inode_operations proc_task_inode_operations = { |
28a6d671 EB |
2537 | .lookup = proc_task_lookup, |
2538 | .getattr = proc_task_getattr, | |
2539 | .setattr = proc_setattr, | |
2540 | }; | |
2541 | ||
00977a59 | 2542 | static const struct file_operations proc_task_operations = { |
28a6d671 EB |
2543 | .read = generic_read_dir, |
2544 | .readdir = proc_task_readdir, | |
2545 | }; |