1 | // SPDX-License-Identifier: GPL-2.0 |
---|---|
2 | /* |
3 | * linux/fs/proc/base.c |
4 | * |
5 | * Copyright (C) 1991, 1992 Linus Torvalds |
6 | * |
7 | * proc base directory handling functions |
8 | * |
9 | * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. |
10 | * Instead of using magical inumbers to determine the kind of object |
11 | * we allocate and fill in-core inodes upon lookup. They don't even |
12 | * go into icache. We cache the reference to task_struct upon lookup too. |
13 | * Eventually it should become a filesystem in its own. We don't use the |
14 | * rest of procfs anymore. |
15 | * |
16 | * |
17 | * Changelog: |
18 | * 17-Jan-2005 |
19 | * Allan Bezerra |
20 | * Bruna Moreira <bruna.moreira@indt.org.br> |
21 | * Edjard Mota <edjard.mota@indt.org.br> |
22 | * Ilias Biris <ilias.biris@indt.org.br> |
23 | * Mauricio Lin <mauricio.lin@indt.org.br> |
24 | * |
25 | * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT |
26 | * |
27 | * A new process specific entry (smaps) included in /proc. It shows the |
28 | * size of rss for each memory area. The maps entry lacks information |
29 | * about physical memory size (rss) for each mapped file, i.e., |
30 | * rss information for executables and library files. |
31 | * This additional information is useful for any tools that need to know |
32 | * about physical memory consumption for a process specific library. |
33 | * |
34 | * Changelog: |
35 | * 21-Feb-2005 |
36 | * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT |
37 | * Pud inclusion in the page table walking. |
38 | * |
39 | * ChangeLog: |
40 | * 10-Mar-2005 |
41 | * 10LE Instituto Nokia de Tecnologia - INdT: |
42 | * A better way to walks through the page table as suggested by Hugh Dickins. |
43 | * |
44 | * Simo Piiroinen <simo.piiroinen@nokia.com>: |
45 | * Smaps information related to shared, private, clean and dirty pages. |
46 | * |
47 | * Paul Mundt <paul.mundt@nokia.com>: |
48 | * Overall revision about smaps. |
49 | */ |
50 | |
51 | #include <linux/uaccess.h> |
52 | |
53 | #include <linux/errno.h> |
54 | #include <linux/time.h> |
55 | #include <linux/proc_fs.h> |
56 | #include <linux/stat.h> |
57 | #include <linux/task_io_accounting_ops.h> |
58 | #include <linux/init.h> |
59 | #include <linux/capability.h> |
60 | #include <linux/file.h> |
61 | #include <linux/generic-radix-tree.h> |
62 | #include <linux/string.h> |
63 | #include <linux/seq_file.h> |
64 | #include <linux/namei.h> |
65 | #include <linux/mnt_namespace.h> |
66 | #include <linux/mm.h> |
67 | #include <linux/swap.h> |
68 | #include <linux/rcupdate.h> |
69 | #include <linux/kallsyms.h> |
70 | #include <linux/stacktrace.h> |
71 | #include <linux/resource.h> |
72 | #include <linux/module.h> |
73 | #include <linux/mount.h> |
74 | #include <linux/security.h> |
75 | #include <linux/ptrace.h> |
76 | #include <linux/printk.h> |
77 | #include <linux/cache.h> |
78 | #include <linux/cgroup.h> |
79 | #include <linux/cpuset.h> |
80 | #include <linux/audit.h> |
81 | #include <linux/poll.h> |
82 | #include <linux/nsproxy.h> |
83 | #include <linux/oom.h> |
84 | #include <linux/elf.h> |
85 | #include <linux/pid_namespace.h> |
86 | #include <linux/user_namespace.h> |
87 | #include <linux/fs_parser.h> |
88 | #include <linux/fs_struct.h> |
89 | #include <linux/slab.h> |
90 | #include <linux/sched/autogroup.h> |
91 | #include <linux/sched/mm.h> |
92 | #include <linux/sched/coredump.h> |
93 | #include <linux/sched/debug.h> |
94 | #include <linux/sched/stat.h> |
95 | #include <linux/posix-timers.h> |
96 | #include <linux/time_namespace.h> |
97 | #include <linux/resctrl.h> |
98 | #include <linux/cn_proc.h> |
99 | #include <linux/ksm.h> |
100 | #include <uapi/linux/lsm.h> |
101 | #include <trace/events/oom.h> |
102 | #include "internal.h" |
103 | #include "fd.h" |
104 | |
105 | #include "../../lib/kstrtox.h" |
106 | |
107 | /* NOTE: |
108 | * Implementing inode permission operations in /proc is almost |
109 | * certainly an error. Permission checks need to happen during |
110 | * each system call not at open time. The reason is that most of |
111 | * what we wish to check for permissions in /proc varies at runtime. |
112 | * |
113 | * The classic example of a problem is opening file descriptors |
114 | * in /proc for a task before it execs a suid executable. |
115 | */ |
116 | |
117 | static u8 nlink_tid __ro_after_init; |
118 | static u8 nlink_tgid __ro_after_init; |
119 | |
120 | enum proc_mem_force { |
121 | PROC_MEM_FORCE_ALWAYS, |
122 | PROC_MEM_FORCE_PTRACE, |
123 | PROC_MEM_FORCE_NEVER |
124 | }; |
125 | |
126 | static enum proc_mem_force proc_mem_force_override __ro_after_init = |
127 | IS_ENABLED(CONFIG_PROC_MEM_NO_FORCE) ? PROC_MEM_FORCE_NEVER : |
128 | IS_ENABLED(CONFIG_PROC_MEM_FORCE_PTRACE) ? PROC_MEM_FORCE_PTRACE : |
129 | PROC_MEM_FORCE_ALWAYS; |
130 | |
131 | static const struct constant_table proc_mem_force_table[] __initconst = { |
132 | { "always", PROC_MEM_FORCE_ALWAYS }, |
133 | { "ptrace", PROC_MEM_FORCE_PTRACE }, |
134 | { "never", PROC_MEM_FORCE_NEVER }, |
135 | { } |
136 | }; |
137 | |
138 | static int __init early_proc_mem_force_override(char *buf) |
139 | { |
140 | if (!buf) |
141 | return -EINVAL; |
142 | |
143 | /* |
144 | * lookup_constant() defaults to proc_mem_force_override to preseve |
145 | * the initial Kconfig choice in case an invalid param gets passed. |
146 | */ |
147 | proc_mem_force_override = lookup_constant(tbl: proc_mem_force_table, |
148 | name: buf, not_found: proc_mem_force_override); |
149 | |
150 | return 0; |
151 | } |
152 | early_param("proc_mem.force_override", early_proc_mem_force_override); |
153 | |
154 | struct pid_entry { |
155 | const char *name; |
156 | unsigned int len; |
157 | umode_t mode; |
158 | const struct inode_operations *iop; |
159 | const struct file_operations *fop; |
160 | union proc_op op; |
161 | }; |
162 | |
163 | #define NOD(NAME, MODE, IOP, FOP, OP) { \ |
164 | .name = (NAME), \ |
165 | .len = sizeof(NAME) - 1, \ |
166 | .mode = MODE, \ |
167 | .iop = IOP, \ |
168 | .fop = FOP, \ |
169 | .op = OP, \ |
170 | } |
171 | |
172 | #define DIR(NAME, MODE, iops, fops) \ |
173 | NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) |
174 | #define LNK(NAME, get_link) \ |
175 | NOD(NAME, (S_IFLNK|S_IRWXUGO), \ |
176 | &proc_pid_link_inode_operations, NULL, \ |
177 | { .proc_get_link = get_link } ) |
178 | #define REG(NAME, MODE, fops) \ |
179 | NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) |
180 | #define ONE(NAME, MODE, show) \ |
181 | NOD(NAME, (S_IFREG|(MODE)), \ |
182 | NULL, &proc_single_file_operations, \ |
183 | { .proc_show = show } ) |
184 | #define ATTR(LSMID, NAME, MODE) \ |
185 | NOD(NAME, (S_IFREG|(MODE)), \ |
186 | NULL, &proc_pid_attr_operations, \ |
187 | { .lsmid = LSMID }) |
188 | |
189 | /* |
190 | * Count the number of hardlinks for the pid_entry table, excluding the . |
191 | * and .. links. |
192 | */ |
193 | static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, |
194 | unsigned int n) |
195 | { |
196 | unsigned int i; |
197 | unsigned int count; |
198 | |
199 | count = 2; |
200 | for (i = 0; i < n; ++i) { |
201 | if (S_ISDIR(entries[i].mode)) |
202 | ++count; |
203 | } |
204 | |
205 | return count; |
206 | } |
207 | |
208 | static int get_task_root(struct task_struct *task, struct path *root) |
209 | { |
210 | int result = -ENOENT; |
211 | |
212 | task_lock(p: task); |
213 | if (task->fs) { |
214 | get_fs_root(fs: task->fs, root); |
215 | result = 0; |
216 | } |
217 | task_unlock(p: task); |
218 | return result; |
219 | } |
220 | |
221 | static int proc_cwd_link(struct dentry *dentry, struct path *path) |
222 | { |
223 | struct task_struct *task = get_proc_task(inode: d_inode(dentry)); |
224 | int result = -ENOENT; |
225 | |
226 | if (task) { |
227 | task_lock(p: task); |
228 | if (task->fs) { |
229 | get_fs_pwd(fs: task->fs, pwd: path); |
230 | result = 0; |
231 | } |
232 | task_unlock(p: task); |
233 | put_task_struct(t: task); |
234 | } |
235 | return result; |
236 | } |
237 | |
238 | static int proc_root_link(struct dentry *dentry, struct path *path) |
239 | { |
240 | struct task_struct *task = get_proc_task(inode: d_inode(dentry)); |
241 | int result = -ENOENT; |
242 | |
243 | if (task) { |
244 | result = get_task_root(task, root: path); |
245 | put_task_struct(t: task); |
246 | } |
247 | return result; |
248 | } |
249 | |
250 | /* |
251 | * If the user used setproctitle(), we just get the string from |
252 | * user space at arg_start, and limit it to a maximum of one page. |
253 | */ |
254 | static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf, |
255 | size_t count, unsigned long pos, |
256 | unsigned long arg_start) |
257 | { |
258 | char *page; |
259 | int ret, got; |
260 | |
261 | if (pos >= PAGE_SIZE) |
262 | return 0; |
263 | |
264 | page = (char *)__get_free_page(GFP_KERNEL); |
265 | if (!page) |
266 | return -ENOMEM; |
267 | |
268 | ret = 0; |
269 | got = access_remote_vm(mm, addr: arg_start, buf: page, PAGE_SIZE, gup_flags: FOLL_ANON); |
270 | if (got > 0) { |
271 | int len = strnlen(p: page, maxlen: got); |
272 | |
273 | /* Include the NUL character if it was found */ |
274 | if (len < got) |
275 | len++; |
276 | |
277 | if (len > pos) { |
278 | len -= pos; |
279 | if (len > count) |
280 | len = count; |
281 | len -= copy_to_user(to: buf, from: page+pos, n: len); |
282 | if (!len) |
283 | len = -EFAULT; |
284 | ret = len; |
285 | } |
286 | } |
287 | free_page((unsigned long)page); |
288 | return ret; |
289 | } |
290 | |
291 | static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, |
292 | size_t count, loff_t *ppos) |
293 | { |
294 | unsigned long arg_start, arg_end, env_start, env_end; |
295 | unsigned long pos, len; |
296 | char *page, c; |
297 | |
298 | /* Check if process spawned far enough to have cmdline. */ |
299 | if (!mm->env_end) |
300 | return 0; |
301 | |
302 | spin_lock(lock: &mm->arg_lock); |
303 | arg_start = mm->arg_start; |
304 | arg_end = mm->arg_end; |
305 | env_start = mm->env_start; |
306 | env_end = mm->env_end; |
307 | spin_unlock(lock: &mm->arg_lock); |
308 | |
309 | if (arg_start >= arg_end) |
310 | return 0; |
311 | |
312 | /* |
313 | * We allow setproctitle() to overwrite the argument |
314 | * strings, and overflow past the original end. But |
315 | * only when it overflows into the environment area. |
316 | */ |
317 | if (env_start != arg_end || env_end < env_start) |
318 | env_start = env_end = arg_end; |
319 | len = env_end - arg_start; |
320 | |
321 | /* We're not going to care if "*ppos" has high bits set */ |
322 | pos = *ppos; |
323 | if (pos >= len) |
324 | return 0; |
325 | if (count > len - pos) |
326 | count = len - pos; |
327 | if (!count) |
328 | return 0; |
329 | |
330 | /* |
331 | * Magical special case: if the argv[] end byte is not |
332 | * zero, the user has overwritten it with setproctitle(3). |
333 | * |
334 | * Possible future enhancement: do this only once when |
335 | * pos is 0, and set a flag in the 'struct file'. |
336 | */ |
337 | if (access_remote_vm(mm, addr: arg_end-1, buf: &c, len: 1, gup_flags: FOLL_ANON) == 1 && c) |
338 | return get_mm_proctitle(mm, buf, count, pos, arg_start); |
339 | |
340 | /* |
341 | * For the non-setproctitle() case we limit things strictly |
342 | * to the [arg_start, arg_end[ range. |
343 | */ |
344 | pos += arg_start; |
345 | if (pos < arg_start || pos >= arg_end) |
346 | return 0; |
347 | if (count > arg_end - pos) |
348 | count = arg_end - pos; |
349 | |
350 | page = (char *)__get_free_page(GFP_KERNEL); |
351 | if (!page) |
352 | return -ENOMEM; |
353 | |
354 | len = 0; |
355 | while (count) { |
356 | int got; |
357 | size_t size = min_t(size_t, PAGE_SIZE, count); |
358 | |
359 | got = access_remote_vm(mm, addr: pos, buf: page, len: size, gup_flags: FOLL_ANON); |
360 | if (got <= 0) |
361 | break; |
362 | got -= copy_to_user(to: buf, from: page, n: got); |
363 | if (unlikely(!got)) { |
364 | if (!len) |
365 | len = -EFAULT; |
366 | break; |
367 | } |
368 | pos += got; |
369 | buf += got; |
370 | len += got; |
371 | count -= got; |
372 | } |
373 | |
374 | free_page((unsigned long)page); |
375 | return len; |
376 | } |
377 | |
378 | static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf, |
379 | size_t count, loff_t *pos) |
380 | { |
381 | struct mm_struct *mm; |
382 | ssize_t ret; |
383 | |
384 | mm = get_task_mm(task: tsk); |
385 | if (!mm) |
386 | return 0; |
387 | |
388 | ret = get_mm_cmdline(mm, buf, count, ppos: pos); |
389 | mmput(mm); |
390 | return ret; |
391 | } |
392 | |
393 | static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, |
394 | size_t count, loff_t *pos) |
395 | { |
396 | struct task_struct *tsk; |
397 | ssize_t ret; |
398 | |
399 | BUG_ON(*pos < 0); |
400 | |
401 | tsk = get_proc_task(inode: file_inode(f: file)); |
402 | if (!tsk) |
403 | return -ESRCH; |
404 | ret = get_task_cmdline(tsk, buf, count, pos); |
405 | put_task_struct(t: tsk); |
406 | if (ret > 0) |
407 | *pos += ret; |
408 | return ret; |
409 | } |
410 | |
411 | static const struct file_operations proc_pid_cmdline_ops = { |
412 | .read = proc_pid_cmdline_read, |
413 | .llseek = generic_file_llseek, |
414 | }; |
415 | |
416 | #ifdef CONFIG_KALLSYMS |
417 | /* |
418 | * Provides a wchan file via kallsyms in a proper one-value-per-file format. |
419 | * Returns the resolved symbol to user space. |
420 | */ |
421 | static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, |
422 | struct pid *pid, struct task_struct *task) |
423 | { |
424 | unsigned long wchan; |
425 | char symname[KSYM_NAME_LEN]; |
426 | |
427 | if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
428 | goto print0; |
429 | |
430 | wchan = get_wchan(p: task); |
431 | if (wchan && !lookup_symbol_name(addr: wchan, symname)) { |
432 | seq_puts(m, s: symname); |
433 | return 0; |
434 | } |
435 | |
436 | print0: |
437 | seq_putc(m, c: '0'); |
438 | return 0; |
439 | } |
440 | #endif /* CONFIG_KALLSYMS */ |
441 | |
442 | static int lock_trace(struct task_struct *task) |
443 | { |
444 | int err = down_read_killable(sem: &task->signal->exec_update_lock); |
445 | if (err) |
446 | return err; |
447 | if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { |
448 | up_read(sem: &task->signal->exec_update_lock); |
449 | return -EPERM; |
450 | } |
451 | return 0; |
452 | } |
453 | |
454 | static void unlock_trace(struct task_struct *task) |
455 | { |
456 | up_read(sem: &task->signal->exec_update_lock); |
457 | } |
458 | |
459 | #ifdef CONFIG_STACKTRACE |
460 | |
461 | #define MAX_STACK_TRACE_DEPTH 64 |
462 | |
463 | static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, |
464 | struct pid *pid, struct task_struct *task) |
465 | { |
466 | unsigned long *entries; |
467 | int err; |
468 | |
469 | /* |
470 | * The ability to racily run the kernel stack unwinder on a running task |
471 | * and then observe the unwinder output is scary; while it is useful for |
472 | * debugging kernel issues, it can also allow an attacker to leak kernel |
473 | * stack contents. |
474 | * Doing this in a manner that is at least safe from races would require |
475 | * some work to ensure that the remote task can not be scheduled; and |
476 | * even then, this would still expose the unwinder as local attack |
477 | * surface. |
478 | * Therefore, this interface is restricted to root. |
479 | */ |
480 | if (!file_ns_capable(file: m->file, ns: &init_user_ns, CAP_SYS_ADMIN)) |
481 | return -EACCES; |
482 | |
483 | entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries), |
484 | GFP_KERNEL); |
485 | if (!entries) |
486 | return -ENOMEM; |
487 | |
488 | err = lock_trace(task); |
489 | if (!err) { |
490 | unsigned int i, nr_entries; |
491 | |
492 | nr_entries = stack_trace_save_tsk(task, store: entries, |
493 | MAX_STACK_TRACE_DEPTH, skipnr: 0); |
494 | |
495 | for (i = 0; i < nr_entries; i++) { |
496 | seq_printf(m, fmt: "[<0>] %pB\n", (void *)entries[i]); |
497 | } |
498 | |
499 | unlock_trace(task); |
500 | } |
501 | kfree(objp: entries); |
502 | |
503 | return err; |
504 | } |
505 | #endif |
506 | |
507 | #ifdef CONFIG_SCHED_INFO |
508 | /* |
509 | * Provides /proc/PID/schedstat |
510 | */ |
511 | static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, |
512 | struct pid *pid, struct task_struct *task) |
513 | { |
514 | if (unlikely(!sched_info_on())) |
515 | seq_puts(m, s: "0 0 0\n"); |
516 | else |
517 | seq_printf(m, fmt: "%llu %llu %lu\n", |
518 | (unsigned long long)task->se.sum_exec_runtime, |
519 | (unsigned long long)task->sched_info.run_delay, |
520 | task->sched_info.pcount); |
521 | |
522 | return 0; |
523 | } |
524 | #endif |
525 | |
526 | #ifdef CONFIG_LATENCYTOP |
527 | static int lstats_show_proc(struct seq_file *m, void *v) |
528 | { |
529 | int i; |
530 | struct inode *inode = m->private; |
531 | struct task_struct *task = get_proc_task(inode); |
532 | |
533 | if (!task) |
534 | return -ESRCH; |
535 | seq_puts(m, s: "Latency Top version : v0.1\n"); |
536 | for (i = 0; i < LT_SAVECOUNT; i++) { |
537 | struct latency_record *lr = &task->latency_record[i]; |
538 | if (lr->backtrace[0]) { |
539 | int q; |
540 | seq_printf(m, fmt: "%i %li %li", |
541 | lr->count, lr->time, lr->max); |
542 | for (q = 0; q < LT_BACKTRACEDEPTH; q++) { |
543 | unsigned long bt = lr->backtrace[q]; |
544 | |
545 | if (!bt) |
546 | break; |
547 | seq_printf(m, fmt: " %ps", (void *)bt); |
548 | } |
549 | seq_putc(m, c: '\n'); |
550 | } |
551 | |
552 | } |
553 | put_task_struct(t: task); |
554 | return 0; |
555 | } |
556 | |
557 | static int lstats_open(struct inode *inode, struct file *file) |
558 | { |
559 | return single_open(file, lstats_show_proc, inode); |
560 | } |
561 | |
562 | static ssize_t lstats_write(struct file *file, const char __user *buf, |
563 | size_t count, loff_t *offs) |
564 | { |
565 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
566 | |
567 | if (!task) |
568 | return -ESRCH; |
569 | clear_tsk_latency_tracing(p: task); |
570 | put_task_struct(t: task); |
571 | |
572 | return count; |
573 | } |
574 | |
575 | static const struct file_operations proc_lstats_operations = { |
576 | .open = lstats_open, |
577 | .read = seq_read, |
578 | .write = lstats_write, |
579 | .llseek = seq_lseek, |
580 | .release = single_release, |
581 | }; |
582 | |
583 | #endif |
584 | |
585 | static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, |
586 | struct pid *pid, struct task_struct *task) |
587 | { |
588 | unsigned long totalpages = totalram_pages() + total_swap_pages; |
589 | unsigned long points = 0; |
590 | long badness; |
591 | |
592 | badness = oom_badness(p: task, totalpages); |
593 | /* |
594 | * Special case OOM_SCORE_ADJ_MIN for all others scale the |
595 | * badness value into [0, 2000] range which we have been |
596 | * exporting for a long time so userspace might depend on it. |
597 | */ |
598 | if (badness != LONG_MIN) |
599 | points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3; |
600 | |
601 | seq_printf(m, fmt: "%lu\n", points); |
602 | |
603 | return 0; |
604 | } |
605 | |
606 | struct limit_names { |
607 | const char *name; |
608 | const char *unit; |
609 | }; |
610 | |
611 | static const struct limit_names lnames[RLIM_NLIMITS] = { |
612 | [RLIMIT_CPU] = {"Max cpu time", "seconds"}, |
613 | [RLIMIT_FSIZE] = {"Max file size", "bytes"}, |
614 | [RLIMIT_DATA] = {"Max data size", "bytes"}, |
615 | [RLIMIT_STACK] = {"Max stack size", "bytes"}, |
616 | [RLIMIT_CORE] = {"Max core file size", "bytes"}, |
617 | [RLIMIT_RSS] = {"Max resident set", "bytes"}, |
618 | [RLIMIT_NPROC] = {"Max processes", "processes"}, |
619 | [RLIMIT_NOFILE] = {"Max open files", "files"}, |
620 | [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, |
621 | [RLIMIT_AS] = {"Max address space", "bytes"}, |
622 | [RLIMIT_LOCKS] = {"Max file locks", "locks"}, |
623 | [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, |
624 | [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, |
625 | [RLIMIT_NICE] = {"Max nice priority", NULL}, |
626 | [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, |
627 | [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, |
628 | }; |
629 | |
630 | /* Display limits for a process */ |
631 | static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, |
632 | struct pid *pid, struct task_struct *task) |
633 | { |
634 | unsigned int i; |
635 | unsigned long flags; |
636 | |
637 | struct rlimit rlim[RLIM_NLIMITS]; |
638 | |
639 | if (!lock_task_sighand(task, flags: &flags)) |
640 | return 0; |
641 | memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); |
642 | unlock_task_sighand(task, flags: &flags); |
643 | |
644 | /* |
645 | * print the file header |
646 | */ |
647 | seq_puts(m, s: "Limit " |
648 | "Soft Limit " |
649 | "Hard Limit " |
650 | "Units \n"); |
651 | |
652 | for (i = 0; i < RLIM_NLIMITS; i++) { |
653 | if (rlim[i].rlim_cur == RLIM_INFINITY) |
654 | seq_printf(m, fmt: "%-25s %-20s ", |
655 | lnames[i].name, "unlimited"); |
656 | else |
657 | seq_printf(m, fmt: "%-25s %-20lu ", |
658 | lnames[i].name, rlim[i].rlim_cur); |
659 | |
660 | if (rlim[i].rlim_max == RLIM_INFINITY) |
661 | seq_printf(m, fmt: "%-20s ", "unlimited"); |
662 | else |
663 | seq_printf(m, fmt: "%-20lu ", rlim[i].rlim_max); |
664 | |
665 | if (lnames[i].unit) |
666 | seq_printf(m, fmt: "%-10s\n", lnames[i].unit); |
667 | else |
668 | seq_putc(m, c: '\n'); |
669 | } |
670 | |
671 | return 0; |
672 | } |
673 | |
674 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
675 | static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, |
676 | struct pid *pid, struct task_struct *task) |
677 | { |
678 | struct syscall_info info; |
679 | u64 *args = &info.data.args[0]; |
680 | int res; |
681 | |
682 | res = lock_trace(task); |
683 | if (res) |
684 | return res; |
685 | |
686 | if (task_current_syscall(target: task, info: &info)) |
687 | seq_puts(m, s: "running\n"); |
688 | else if (info.data.nr < 0) |
689 | seq_printf(m, fmt: "%d 0x%llx 0x%llx\n", |
690 | info.data.nr, info.sp, info.data.instruction_pointer); |
691 | else |
692 | seq_printf(m, |
693 | fmt: "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n", |
694 | info.data.nr, |
695 | args[0], args[1], args[2], args[3], args[4], args[5], |
696 | info.sp, info.data.instruction_pointer); |
697 | unlock_trace(task); |
698 | |
699 | return 0; |
700 | } |
701 | #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ |
702 | |
703 | /************************************************************************/ |
704 | /* Here the fs part begins */ |
705 | /************************************************************************/ |
706 | |
707 | /* permission checks */ |
708 | static bool proc_fd_access_allowed(struct inode *inode) |
709 | { |
710 | struct task_struct *task; |
711 | bool allowed = false; |
712 | /* Allow access to a task's file descriptors if it is us or we |
713 | * may use ptrace attach to the process and find out that |
714 | * information. |
715 | */ |
716 | task = get_proc_task(inode); |
717 | if (task) { |
718 | allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); |
719 | put_task_struct(t: task); |
720 | } |
721 | return allowed; |
722 | } |
723 | |
724 | int proc_setattr(struct mnt_idmap *idmap, struct dentry *dentry, |
725 | struct iattr *attr) |
726 | { |
727 | int error; |
728 | struct inode *inode = d_inode(dentry); |
729 | |
730 | if (attr->ia_valid & ATTR_MODE) |
731 | return -EPERM; |
732 | |
733 | error = setattr_prepare(&nop_mnt_idmap, dentry, attr); |
734 | if (error) |
735 | return error; |
736 | |
737 | setattr_copy(&nop_mnt_idmap, inode, attr); |
738 | return 0; |
739 | } |
740 | |
741 | /* |
742 | * May current process learn task's sched/cmdline info (for hide_pid_min=1) |
743 | * or euid/egid (for hide_pid_min=2)? |
744 | */ |
745 | static bool has_pid_permissions(struct proc_fs_info *fs_info, |
746 | struct task_struct *task, |
747 | enum proc_hidepid hide_pid_min) |
748 | { |
749 | /* |
750 | * If 'hidpid' mount option is set force a ptrace check, |
751 | * we indicate that we are using a filesystem syscall |
752 | * by passing PTRACE_MODE_READ_FSCREDS |
753 | */ |
754 | if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) |
755 | return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); |
756 | |
757 | if (fs_info->hide_pid < hide_pid_min) |
758 | return true; |
759 | if (in_group_p(fs_info->pid_gid)) |
760 | return true; |
761 | return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); |
762 | } |
763 | |
764 | |
765 | static int proc_pid_permission(struct mnt_idmap *idmap, |
766 | struct inode *inode, int mask) |
767 | { |
768 | struct proc_fs_info *fs_info = proc_sb_info(sb: inode->i_sb); |
769 | struct task_struct *task; |
770 | bool has_perms; |
771 | |
772 | task = get_proc_task(inode); |
773 | if (!task) |
774 | return -ESRCH; |
775 | has_perms = has_pid_permissions(fs_info, task, hide_pid_min: HIDEPID_NO_ACCESS); |
776 | put_task_struct(t: task); |
777 | |
778 | if (!has_perms) { |
779 | if (fs_info->hide_pid == HIDEPID_INVISIBLE) { |
780 | /* |
781 | * Let's make getdents(), stat(), and open() |
782 | * consistent with each other. If a process |
783 | * may not stat() a file, it shouldn't be seen |
784 | * in procfs at all. |
785 | */ |
786 | return -ENOENT; |
787 | } |
788 | |
789 | return -EPERM; |
790 | } |
791 | return generic_permission(&nop_mnt_idmap, inode, mask); |
792 | } |
793 | |
794 | |
795 | |
796 | static const struct inode_operations proc_def_inode_operations = { |
797 | .setattr = proc_setattr, |
798 | }; |
799 | |
800 | static int proc_single_show(struct seq_file *m, void *v) |
801 | { |
802 | struct inode *inode = m->private; |
803 | struct pid_namespace *ns = proc_pid_ns(sb: inode->i_sb); |
804 | struct pid *pid = proc_pid(inode); |
805 | struct task_struct *task; |
806 | int ret; |
807 | |
808 | task = get_pid_task(pid, PIDTYPE_PID); |
809 | if (!task) |
810 | return -ESRCH; |
811 | |
812 | ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); |
813 | |
814 | put_task_struct(t: task); |
815 | return ret; |
816 | } |
817 | |
818 | static int proc_single_open(struct inode *inode, struct file *filp) |
819 | { |
820 | return single_open(filp, proc_single_show, inode); |
821 | } |
822 | |
823 | static const struct file_operations proc_single_file_operations = { |
824 | .open = proc_single_open, |
825 | .read = seq_read, |
826 | .llseek = seq_lseek, |
827 | .release = single_release, |
828 | }; |
829 | |
830 | /* |
831 | * proc_mem_open() can return errno, NULL or mm_struct*. |
832 | * |
833 | * - Returns NULL if the task has no mm (PF_KTHREAD or PF_EXITING) |
834 | * - Returns mm_struct* on success |
835 | * - Returns error code on failure |
836 | */ |
837 | struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) |
838 | { |
839 | struct task_struct *task = get_proc_task(inode); |
840 | struct mm_struct *mm; |
841 | |
842 | if (!task) |
843 | return ERR_PTR(error: -ESRCH); |
844 | |
845 | mm = mm_access(task, mode: mode | PTRACE_MODE_FSCREDS); |
846 | put_task_struct(t: task); |
847 | |
848 | if (IS_ERR(ptr: mm)) |
849 | return mm == ERR_PTR(error: -ESRCH) ? NULL : mm; |
850 | |
851 | /* ensure this mm_struct can't be freed */ |
852 | mmgrab(mm); |
853 | /* but do not pin its memory */ |
854 | mmput(mm); |
855 | |
856 | return mm; |
857 | } |
858 | |
859 | static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) |
860 | { |
861 | struct mm_struct *mm = proc_mem_open(inode, mode); |
862 | |
863 | if (IS_ERR_OR_NULL(ptr: mm)) |
864 | return mm ? PTR_ERR(ptr: mm) : -ESRCH; |
865 | |
866 | file->private_data = mm; |
867 | return 0; |
868 | } |
869 | |
870 | static int mem_open(struct inode *inode, struct file *file) |
871 | { |
872 | if (WARN_ON_ONCE(!(file->f_op->fop_flags & FOP_UNSIGNED_OFFSET))) |
873 | return -EINVAL; |
874 | return __mem_open(inode, file, PTRACE_MODE_ATTACH); |
875 | } |
876 | |
877 | static bool proc_mem_foll_force(struct file *file, struct mm_struct *mm) |
878 | { |
879 | struct task_struct *task; |
880 | bool ptrace_active = false; |
881 | |
882 | switch (proc_mem_force_override) { |
883 | case PROC_MEM_FORCE_NEVER: |
884 | return false; |
885 | case PROC_MEM_FORCE_PTRACE: |
886 | task = get_proc_task(inode: file_inode(f: file)); |
887 | if (task) { |
888 | ptrace_active = READ_ONCE(task->ptrace) && |
889 | READ_ONCE(task->mm) == mm && |
890 | READ_ONCE(task->parent) == current; |
891 | put_task_struct(t: task); |
892 | } |
893 | return ptrace_active; |
894 | default: |
895 | return true; |
896 | } |
897 | } |
898 | |
899 | static ssize_t mem_rw(struct file *file, char __user *buf, |
900 | size_t count, loff_t *ppos, int write) |
901 | { |
902 | struct mm_struct *mm = file->private_data; |
903 | unsigned long addr = *ppos; |
904 | ssize_t copied; |
905 | char *page; |
906 | unsigned int flags; |
907 | |
908 | if (!mm) |
909 | return 0; |
910 | |
911 | page = (char *)__get_free_page(GFP_KERNEL); |
912 | if (!page) |
913 | return -ENOMEM; |
914 | |
915 | copied = 0; |
916 | if (!mmget_not_zero(mm)) |
917 | goto free; |
918 | |
919 | flags = write ? FOLL_WRITE : 0; |
920 | if (proc_mem_foll_force(file, mm)) |
921 | flags |= FOLL_FORCE; |
922 | |
923 | while (count > 0) { |
924 | size_t this_len = min_t(size_t, count, PAGE_SIZE); |
925 | |
926 | if (write && copy_from_user(to: page, from: buf, n: this_len)) { |
927 | copied = -EFAULT; |
928 | break; |
929 | } |
930 | |
931 | this_len = access_remote_vm(mm, addr, buf: page, len: this_len, gup_flags: flags); |
932 | if (!this_len) { |
933 | if (!copied) |
934 | copied = -EIO; |
935 | break; |
936 | } |
937 | |
938 | if (!write && copy_to_user(to: buf, from: page, n: this_len)) { |
939 | copied = -EFAULT; |
940 | break; |
941 | } |
942 | |
943 | buf += this_len; |
944 | addr += this_len; |
945 | copied += this_len; |
946 | count -= this_len; |
947 | } |
948 | *ppos = addr; |
949 | |
950 | mmput(mm); |
951 | free: |
952 | free_page((unsigned long) page); |
953 | return copied; |
954 | } |
955 | |
956 | static ssize_t mem_read(struct file *file, char __user *buf, |
957 | size_t count, loff_t *ppos) |
958 | { |
959 | return mem_rw(file, buf, count, ppos, write: 0); |
960 | } |
961 | |
962 | static ssize_t mem_write(struct file *file, const char __user *buf, |
963 | size_t count, loff_t *ppos) |
964 | { |
965 | return mem_rw(file, buf: (char __user*)buf, count, ppos, write: 1); |
966 | } |
967 | |
968 | loff_t mem_lseek(struct file *file, loff_t offset, int orig) |
969 | { |
970 | switch (orig) { |
971 | case 0: |
972 | file->f_pos = offset; |
973 | break; |
974 | case 1: |
975 | file->f_pos += offset; |
976 | break; |
977 | default: |
978 | return -EINVAL; |
979 | } |
980 | force_successful_syscall_return(); |
981 | return file->f_pos; |
982 | } |
983 | |
984 | static int mem_release(struct inode *inode, struct file *file) |
985 | { |
986 | struct mm_struct *mm = file->private_data; |
987 | if (mm) |
988 | mmdrop(mm); |
989 | return 0; |
990 | } |
991 | |
992 | static const struct file_operations proc_mem_operations = { |
993 | .llseek = mem_lseek, |
994 | .read = mem_read, |
995 | .write = mem_write, |
996 | .open = mem_open, |
997 | .release = mem_release, |
998 | .fop_flags = FOP_UNSIGNED_OFFSET, |
999 | }; |
1000 | |
1001 | static int environ_open(struct inode *inode, struct file *file) |
1002 | { |
1003 | return __mem_open(inode, file, PTRACE_MODE_READ); |
1004 | } |
1005 | |
1006 | static ssize_t environ_read(struct file *file, char __user *buf, |
1007 | size_t count, loff_t *ppos) |
1008 | { |
1009 | char *page; |
1010 | unsigned long src = *ppos; |
1011 | int ret = 0; |
1012 | struct mm_struct *mm = file->private_data; |
1013 | unsigned long env_start, env_end; |
1014 | |
1015 | /* Ensure the process spawned far enough to have an environment. */ |
1016 | if (!mm || !mm->env_end) |
1017 | return 0; |
1018 | |
1019 | page = (char *)__get_free_page(GFP_KERNEL); |
1020 | if (!page) |
1021 | return -ENOMEM; |
1022 | |
1023 | ret = 0; |
1024 | if (!mmget_not_zero(mm)) |
1025 | goto free; |
1026 | |
1027 | spin_lock(lock: &mm->arg_lock); |
1028 | env_start = mm->env_start; |
1029 | env_end = mm->env_end; |
1030 | spin_unlock(lock: &mm->arg_lock); |
1031 | |
1032 | while (count > 0) { |
1033 | size_t this_len, max_len; |
1034 | int retval; |
1035 | |
1036 | if (src >= (env_end - env_start)) |
1037 | break; |
1038 | |
1039 | this_len = env_end - (env_start + src); |
1040 | |
1041 | max_len = min_t(size_t, PAGE_SIZE, count); |
1042 | this_len = min(max_len, this_len); |
1043 | |
1044 | retval = access_remote_vm(mm, addr: (env_start + src), buf: page, len: this_len, gup_flags: FOLL_ANON); |
1045 | |
1046 | if (retval <= 0) { |
1047 | ret = retval; |
1048 | break; |
1049 | } |
1050 | |
1051 | if (copy_to_user(to: buf, from: page, n: retval)) { |
1052 | ret = -EFAULT; |
1053 | break; |
1054 | } |
1055 | |
1056 | ret += retval; |
1057 | src += retval; |
1058 | buf += retval; |
1059 | count -= retval; |
1060 | } |
1061 | *ppos = src; |
1062 | mmput(mm); |
1063 | |
1064 | free: |
1065 | free_page((unsigned long) page); |
1066 | return ret; |
1067 | } |
1068 | |
1069 | static const struct file_operations proc_environ_operations = { |
1070 | .open = environ_open, |
1071 | .read = environ_read, |
1072 | .llseek = generic_file_llseek, |
1073 | .release = mem_release, |
1074 | }; |
1075 | |
1076 | static int auxv_open(struct inode *inode, struct file *file) |
1077 | { |
1078 | return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); |
1079 | } |
1080 | |
1081 | static ssize_t auxv_read(struct file *file, char __user *buf, |
1082 | size_t count, loff_t *ppos) |
1083 | { |
1084 | struct mm_struct *mm = file->private_data; |
1085 | unsigned int nwords = 0; |
1086 | |
1087 | if (!mm) |
1088 | return 0; |
1089 | do { |
1090 | nwords += 2; |
1091 | } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ |
1092 | return simple_read_from_buffer(to: buf, count, ppos, from: mm->saved_auxv, |
1093 | available: nwords * sizeof(mm->saved_auxv[0])); |
1094 | } |
1095 | |
1096 | static const struct file_operations proc_auxv_operations = { |
1097 | .open = auxv_open, |
1098 | .read = auxv_read, |
1099 | .llseek = generic_file_llseek, |
1100 | .release = mem_release, |
1101 | }; |
1102 | |
1103 | static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, |
1104 | loff_t *ppos) |
1105 | { |
1106 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
1107 | char buffer[PROC_NUMBUF]; |
1108 | int oom_adj = OOM_ADJUST_MIN; |
1109 | size_t len; |
1110 | |
1111 | if (!task) |
1112 | return -ESRCH; |
1113 | if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) |
1114 | oom_adj = OOM_ADJUST_MAX; |
1115 | else |
1116 | oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / |
1117 | OOM_SCORE_ADJ_MAX; |
1118 | put_task_struct(t: task); |
1119 | if (oom_adj > OOM_ADJUST_MAX) |
1120 | oom_adj = OOM_ADJUST_MAX; |
1121 | len = snprintf(buf: buffer, size: sizeof(buffer), fmt: "%d\n", oom_adj); |
1122 | return simple_read_from_buffer(to: buf, count, ppos, from: buffer, available: len); |
1123 | } |
1124 | |
1125 | static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) |
1126 | { |
1127 | struct mm_struct *mm = NULL; |
1128 | struct task_struct *task; |
1129 | int err = 0; |
1130 | |
1131 | task = get_proc_task(inode: file_inode(f: file)); |
1132 | if (!task) |
1133 | return -ESRCH; |
1134 | |
1135 | mutex_lock(&oom_adj_mutex); |
1136 | if (legacy) { |
1137 | if (oom_adj < task->signal->oom_score_adj && |
1138 | !capable(CAP_SYS_RESOURCE)) { |
1139 | err = -EACCES; |
1140 | goto err_unlock; |
1141 | } |
1142 | /* |
1143 | * /proc/pid/oom_adj is provided for legacy purposes, ask users to use |
1144 | * /proc/pid/oom_score_adj instead. |
1145 | */ |
1146 | pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", |
1147 | current->comm, task_pid_nr(current), task_pid_nr(task), |
1148 | task_pid_nr(task)); |
1149 | } else { |
1150 | if ((short)oom_adj < task->signal->oom_score_adj_min && |
1151 | !capable(CAP_SYS_RESOURCE)) { |
1152 | err = -EACCES; |
1153 | goto err_unlock; |
1154 | } |
1155 | } |
1156 | |
1157 | /* |
1158 | * Make sure we will check other processes sharing the mm if this is |
1159 | * not vfrok which wants its own oom_score_adj. |
1160 | * pin the mm so it doesn't go away and get reused after task_unlock |
1161 | */ |
1162 | if (!task->vfork_done) { |
1163 | struct task_struct *p = find_lock_task_mm(p: task); |
1164 | |
1165 | if (p) { |
1166 | if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) { |
1167 | mm = p->mm; |
1168 | mmgrab(mm); |
1169 | } |
1170 | task_unlock(p); |
1171 | } |
1172 | } |
1173 | |
1174 | task->signal->oom_score_adj = oom_adj; |
1175 | if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) |
1176 | task->signal->oom_score_adj_min = (short)oom_adj; |
1177 | trace_oom_score_adj_update(task); |
1178 | |
1179 | if (mm) { |
1180 | struct task_struct *p; |
1181 | |
1182 | rcu_read_lock(); |
1183 | for_each_process(p) { |
1184 | if (same_thread_group(p1: task, p2: p)) |
1185 | continue; |
1186 | |
1187 | /* do not touch kernel threads or the global init */ |
1188 | if (p->flags & PF_KTHREAD || is_global_init(tsk: p)) |
1189 | continue; |
1190 | |
1191 | task_lock(p); |
1192 | if (!p->vfork_done && process_shares_mm(p, mm)) { |
1193 | p->signal->oom_score_adj = oom_adj; |
1194 | if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) |
1195 | p->signal->oom_score_adj_min = (short)oom_adj; |
1196 | } |
1197 | task_unlock(p); |
1198 | } |
1199 | rcu_read_unlock(); |
1200 | mmdrop(mm); |
1201 | } |
1202 | err_unlock: |
1203 | mutex_unlock(lock: &oom_adj_mutex); |
1204 | put_task_struct(t: task); |
1205 | return err; |
1206 | } |
1207 | |
1208 | /* |
1209 | * /proc/pid/oom_adj exists solely for backwards compatibility with previous |
1210 | * kernels. The effective policy is defined by oom_score_adj, which has a |
1211 | * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. |
1212 | * Values written to oom_adj are simply mapped linearly to oom_score_adj. |
1213 | * Processes that become oom disabled via oom_adj will still be oom disabled |
1214 | * with this implementation. |
1215 | * |
1216 | * oom_adj cannot be removed since existing userspace binaries use it. |
1217 | */ |
1218 | static ssize_t oom_adj_write(struct file *file, const char __user *buf, |
1219 | size_t count, loff_t *ppos) |
1220 | { |
1221 | char buffer[PROC_NUMBUF] = {}; |
1222 | int oom_adj; |
1223 | int err; |
1224 | |
1225 | if (count > sizeof(buffer) - 1) |
1226 | count = sizeof(buffer) - 1; |
1227 | if (copy_from_user(to: buffer, from: buf, n: count)) { |
1228 | err = -EFAULT; |
1229 | goto out; |
1230 | } |
1231 | |
1232 | err = kstrtoint(s: strstrip(str: buffer), base: 0, res: &oom_adj); |
1233 | if (err) |
1234 | goto out; |
1235 | if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && |
1236 | oom_adj != OOM_DISABLE) { |
1237 | err = -EINVAL; |
1238 | goto out; |
1239 | } |
1240 | |
1241 | /* |
1242 | * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum |
1243 | * value is always attainable. |
1244 | */ |
1245 | if (oom_adj == OOM_ADJUST_MAX) |
1246 | oom_adj = OOM_SCORE_ADJ_MAX; |
1247 | else |
1248 | oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; |
1249 | |
1250 | err = __set_oom_adj(file, oom_adj, legacy: true); |
1251 | out: |
1252 | return err < 0 ? err : count; |
1253 | } |
1254 | |
1255 | static const struct file_operations proc_oom_adj_operations = { |
1256 | .read = oom_adj_read, |
1257 | .write = oom_adj_write, |
1258 | .llseek = generic_file_llseek, |
1259 | }; |
1260 | |
1261 | static ssize_t oom_score_adj_read(struct file *file, char __user *buf, |
1262 | size_t count, loff_t *ppos) |
1263 | { |
1264 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
1265 | char buffer[PROC_NUMBUF]; |
1266 | short oom_score_adj = OOM_SCORE_ADJ_MIN; |
1267 | size_t len; |
1268 | |
1269 | if (!task) |
1270 | return -ESRCH; |
1271 | oom_score_adj = task->signal->oom_score_adj; |
1272 | put_task_struct(t: task); |
1273 | len = snprintf(buf: buffer, size: sizeof(buffer), fmt: "%hd\n", oom_score_adj); |
1274 | return simple_read_from_buffer(to: buf, count, ppos, from: buffer, available: len); |
1275 | } |
1276 | |
1277 | static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, |
1278 | size_t count, loff_t *ppos) |
1279 | { |
1280 | char buffer[PROC_NUMBUF] = {}; |
1281 | int oom_score_adj; |
1282 | int err; |
1283 | |
1284 | if (count > sizeof(buffer) - 1) |
1285 | count = sizeof(buffer) - 1; |
1286 | if (copy_from_user(to: buffer, from: buf, n: count)) { |
1287 | err = -EFAULT; |
1288 | goto out; |
1289 | } |
1290 | |
1291 | err = kstrtoint(s: strstrip(str: buffer), base: 0, res: &oom_score_adj); |
1292 | if (err) |
1293 | goto out; |
1294 | if (oom_score_adj < OOM_SCORE_ADJ_MIN || |
1295 | oom_score_adj > OOM_SCORE_ADJ_MAX) { |
1296 | err = -EINVAL; |
1297 | goto out; |
1298 | } |
1299 | |
1300 | err = __set_oom_adj(file, oom_adj: oom_score_adj, legacy: false); |
1301 | out: |
1302 | return err < 0 ? err : count; |
1303 | } |
1304 | |
1305 | static const struct file_operations proc_oom_score_adj_operations = { |
1306 | .read = oom_score_adj_read, |
1307 | .write = oom_score_adj_write, |
1308 | .llseek = default_llseek, |
1309 | }; |
1310 | |
1311 | #ifdef CONFIG_AUDIT |
1312 | #define TMPBUFLEN 11 |
1313 | static ssize_t proc_loginuid_read(struct file * file, char __user * buf, |
1314 | size_t count, loff_t *ppos) |
1315 | { |
1316 | struct inode * inode = file_inode(f: file); |
1317 | struct task_struct *task = get_proc_task(inode); |
1318 | ssize_t length; |
1319 | char tmpbuf[TMPBUFLEN]; |
1320 | |
1321 | if (!task) |
1322 | return -ESRCH; |
1323 | length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u", |
1324 | from_kuid(to: file->f_cred->user_ns, |
1325 | uid: audit_get_loginuid(tsk: task))); |
1326 | put_task_struct(t: task); |
1327 | return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length); |
1328 | } |
1329 | |
1330 | static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, |
1331 | size_t count, loff_t *ppos) |
1332 | { |
1333 | struct inode * inode = file_inode(f: file); |
1334 | uid_t loginuid; |
1335 | kuid_t kloginuid; |
1336 | int rv; |
1337 | |
1338 | /* Don't let kthreads write their own loginuid */ |
1339 | if (current->flags & PF_KTHREAD) |
1340 | return -EPERM; |
1341 | |
1342 | rcu_read_lock(); |
1343 | if (current != pid_task(pid: proc_pid(inode), PIDTYPE_PID)) { |
1344 | rcu_read_unlock(); |
1345 | return -EPERM; |
1346 | } |
1347 | rcu_read_unlock(); |
1348 | |
1349 | if (*ppos != 0) { |
1350 | /* No partial writes. */ |
1351 | return -EINVAL; |
1352 | } |
1353 | |
1354 | rv = kstrtou32_from_user(s: buf, count, base: 10, res: &loginuid); |
1355 | if (rv < 0) |
1356 | return rv; |
1357 | |
1358 | /* is userspace tring to explicitly UNSET the loginuid? */ |
1359 | if (loginuid == AUDIT_UID_UNSET) { |
1360 | kloginuid = INVALID_UID; |
1361 | } else { |
1362 | kloginuid = make_kuid(from: file->f_cred->user_ns, uid: loginuid); |
1363 | if (!uid_valid(uid: kloginuid)) |
1364 | return -EINVAL; |
1365 | } |
1366 | |
1367 | rv = audit_set_loginuid(loginuid: kloginuid); |
1368 | if (rv < 0) |
1369 | return rv; |
1370 | return count; |
1371 | } |
1372 | |
1373 | static const struct file_operations proc_loginuid_operations = { |
1374 | .read = proc_loginuid_read, |
1375 | .write = proc_loginuid_write, |
1376 | .llseek = generic_file_llseek, |
1377 | }; |
1378 | |
1379 | static ssize_t proc_sessionid_read(struct file * file, char __user * buf, |
1380 | size_t count, loff_t *ppos) |
1381 | { |
1382 | struct inode * inode = file_inode(f: file); |
1383 | struct task_struct *task = get_proc_task(inode); |
1384 | ssize_t length; |
1385 | char tmpbuf[TMPBUFLEN]; |
1386 | |
1387 | if (!task) |
1388 | return -ESRCH; |
1389 | length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u", |
1390 | audit_get_sessionid(tsk: task)); |
1391 | put_task_struct(t: task); |
1392 | return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length); |
1393 | } |
1394 | |
1395 | static const struct file_operations proc_sessionid_operations = { |
1396 | .read = proc_sessionid_read, |
1397 | .llseek = generic_file_llseek, |
1398 | }; |
1399 | #endif |
1400 | |
1401 | #ifdef CONFIG_FAULT_INJECTION |
1402 | static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, |
1403 | size_t count, loff_t *ppos) |
1404 | { |
1405 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
1406 | char buffer[PROC_NUMBUF]; |
1407 | size_t len; |
1408 | int make_it_fail; |
1409 | |
1410 | if (!task) |
1411 | return -ESRCH; |
1412 | make_it_fail = task->make_it_fail; |
1413 | put_task_struct(t: task); |
1414 | |
1415 | len = snprintf(buf: buffer, size: sizeof(buffer), fmt: "%i\n", make_it_fail); |
1416 | |
1417 | return simple_read_from_buffer(to: buf, count, ppos, from: buffer, available: len); |
1418 | } |
1419 | |
1420 | static ssize_t proc_fault_inject_write(struct file * file, |
1421 | const char __user * buf, size_t count, loff_t *ppos) |
1422 | { |
1423 | struct task_struct *task; |
1424 | char buffer[PROC_NUMBUF] = {}; |
1425 | int make_it_fail; |
1426 | int rv; |
1427 | |
1428 | if (!capable(CAP_SYS_RESOURCE)) |
1429 | return -EPERM; |
1430 | |
1431 | if (count > sizeof(buffer) - 1) |
1432 | count = sizeof(buffer) - 1; |
1433 | if (copy_from_user(to: buffer, from: buf, n: count)) |
1434 | return -EFAULT; |
1435 | rv = kstrtoint(s: strstrip(str: buffer), base: 0, res: &make_it_fail); |
1436 | if (rv < 0) |
1437 | return rv; |
1438 | if (make_it_fail < 0 || make_it_fail > 1) |
1439 | return -EINVAL; |
1440 | |
1441 | task = get_proc_task(inode: file_inode(f: file)); |
1442 | if (!task) |
1443 | return -ESRCH; |
1444 | task->make_it_fail = make_it_fail; |
1445 | put_task_struct(t: task); |
1446 | |
1447 | return count; |
1448 | } |
1449 | |
1450 | static const struct file_operations proc_fault_inject_operations = { |
1451 | .read = proc_fault_inject_read, |
1452 | .write = proc_fault_inject_write, |
1453 | .llseek = generic_file_llseek, |
1454 | }; |
1455 | |
1456 | static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, |
1457 | size_t count, loff_t *ppos) |
1458 | { |
1459 | struct task_struct *task; |
1460 | int err; |
1461 | unsigned int n; |
1462 | |
1463 | err = kstrtouint_from_user(s: buf, count, base: 0, res: &n); |
1464 | if (err) |
1465 | return err; |
1466 | |
1467 | task = get_proc_task(inode: file_inode(f: file)); |
1468 | if (!task) |
1469 | return -ESRCH; |
1470 | task->fail_nth = n; |
1471 | put_task_struct(t: task); |
1472 | |
1473 | return count; |
1474 | } |
1475 | |
1476 | static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, |
1477 | size_t count, loff_t *ppos) |
1478 | { |
1479 | struct task_struct *task; |
1480 | char numbuf[PROC_NUMBUF]; |
1481 | ssize_t len; |
1482 | |
1483 | task = get_proc_task(inode: file_inode(f: file)); |
1484 | if (!task) |
1485 | return -ESRCH; |
1486 | len = snprintf(buf: numbuf, size: sizeof(numbuf), fmt: "%u\n", task->fail_nth); |
1487 | put_task_struct(t: task); |
1488 | return simple_read_from_buffer(to: buf, count, ppos, from: numbuf, available: len); |
1489 | } |
1490 | |
1491 | static const struct file_operations proc_fail_nth_operations = { |
1492 | .read = proc_fail_nth_read, |
1493 | .write = proc_fail_nth_write, |
1494 | }; |
1495 | #endif |
1496 | |
1497 | |
1498 | /* |
1499 | * Print out various scheduling related per-task fields: |
1500 | */ |
1501 | static int sched_show(struct seq_file *m, void *v) |
1502 | { |
1503 | struct inode *inode = m->private; |
1504 | struct pid_namespace *ns = proc_pid_ns(sb: inode->i_sb); |
1505 | struct task_struct *p; |
1506 | |
1507 | p = get_proc_task(inode); |
1508 | if (!p) |
1509 | return -ESRCH; |
1510 | proc_sched_show_task(p, ns, m); |
1511 | |
1512 | put_task_struct(t: p); |
1513 | |
1514 | return 0; |
1515 | } |
1516 | |
1517 | static ssize_t |
1518 | sched_write(struct file *file, const char __user *buf, |
1519 | size_t count, loff_t *offset) |
1520 | { |
1521 | struct inode *inode = file_inode(f: file); |
1522 | struct task_struct *p; |
1523 | |
1524 | p = get_proc_task(inode); |
1525 | if (!p) |
1526 | return -ESRCH; |
1527 | proc_sched_set_task(p); |
1528 | |
1529 | put_task_struct(t: p); |
1530 | |
1531 | return count; |
1532 | } |
1533 | |
1534 | static int sched_open(struct inode *inode, struct file *filp) |
1535 | { |
1536 | return single_open(filp, sched_show, inode); |
1537 | } |
1538 | |
1539 | static const struct file_operations proc_pid_sched_operations = { |
1540 | .open = sched_open, |
1541 | .read = seq_read, |
1542 | .write = sched_write, |
1543 | .llseek = seq_lseek, |
1544 | .release = single_release, |
1545 | }; |
1546 | |
1547 | #ifdef CONFIG_SCHED_AUTOGROUP |
1548 | /* |
1549 | * Print out autogroup related information: |
1550 | */ |
1551 | static int sched_autogroup_show(struct seq_file *m, void *v) |
1552 | { |
1553 | struct inode *inode = m->private; |
1554 | struct task_struct *p; |
1555 | |
1556 | p = get_proc_task(inode); |
1557 | if (!p) |
1558 | return -ESRCH; |
1559 | proc_sched_autogroup_show_task(p, m); |
1560 | |
1561 | put_task_struct(t: p); |
1562 | |
1563 | return 0; |
1564 | } |
1565 | |
1566 | static ssize_t |
1567 | sched_autogroup_write(struct file *file, const char __user *buf, |
1568 | size_t count, loff_t *offset) |
1569 | { |
1570 | struct inode *inode = file_inode(f: file); |
1571 | struct task_struct *p; |
1572 | char buffer[PROC_NUMBUF] = {}; |
1573 | int nice; |
1574 | int err; |
1575 | |
1576 | if (count > sizeof(buffer) - 1) |
1577 | count = sizeof(buffer) - 1; |
1578 | if (copy_from_user(to: buffer, from: buf, n: count)) |
1579 | return -EFAULT; |
1580 | |
1581 | err = kstrtoint(s: strstrip(str: buffer), base: 0, res: &nice); |
1582 | if (err < 0) |
1583 | return err; |
1584 | |
1585 | p = get_proc_task(inode); |
1586 | if (!p) |
1587 | return -ESRCH; |
1588 | |
1589 | err = proc_sched_autogroup_set_nice(p, nice); |
1590 | if (err) |
1591 | count = err; |
1592 | |
1593 | put_task_struct(t: p); |
1594 | |
1595 | return count; |
1596 | } |
1597 | |
1598 | static int sched_autogroup_open(struct inode *inode, struct file *filp) |
1599 | { |
1600 | int ret; |
1601 | |
1602 | ret = single_open(filp, sched_autogroup_show, NULL); |
1603 | if (!ret) { |
1604 | struct seq_file *m = filp->private_data; |
1605 | |
1606 | m->private = inode; |
1607 | } |
1608 | return ret; |
1609 | } |
1610 | |
1611 | static const struct file_operations proc_pid_sched_autogroup_operations = { |
1612 | .open = sched_autogroup_open, |
1613 | .read = seq_read, |
1614 | .write = sched_autogroup_write, |
1615 | .llseek = seq_lseek, |
1616 | .release = single_release, |
1617 | }; |
1618 | |
1619 | #endif /* CONFIG_SCHED_AUTOGROUP */ |
1620 | |
1621 | #ifdef CONFIG_TIME_NS |
1622 | static int timens_offsets_show(struct seq_file *m, void *v) |
1623 | { |
1624 | struct task_struct *p; |
1625 | |
1626 | p = get_proc_task(inode: file_inode(f: m->file)); |
1627 | if (!p) |
1628 | return -ESRCH; |
1629 | proc_timens_show_offsets(p, m); |
1630 | |
1631 | put_task_struct(t: p); |
1632 | |
1633 | return 0; |
1634 | } |
1635 | |
1636 | static ssize_t timens_offsets_write(struct file *file, const char __user *buf, |
1637 | size_t count, loff_t *ppos) |
1638 | { |
1639 | struct inode *inode = file_inode(f: file); |
1640 | struct proc_timens_offset offsets[2]; |
1641 | char *kbuf = NULL, *pos, *next_line; |
1642 | struct task_struct *p; |
1643 | int ret, noffsets; |
1644 | |
1645 | /* Only allow < page size writes at the beginning of the file */ |
1646 | if ((*ppos != 0) || (count >= PAGE_SIZE)) |
1647 | return -EINVAL; |
1648 | |
1649 | /* Slurp in the user data */ |
1650 | kbuf = memdup_user_nul(buf, count); |
1651 | if (IS_ERR(ptr: kbuf)) |
1652 | return PTR_ERR(ptr: kbuf); |
1653 | |
1654 | /* Parse the user data */ |
1655 | ret = -EINVAL; |
1656 | noffsets = 0; |
1657 | for (pos = kbuf; pos; pos = next_line) { |
1658 | struct proc_timens_offset *off = &offsets[noffsets]; |
1659 | char clock[10]; |
1660 | int err; |
1661 | |
1662 | /* Find the end of line and ensure we don't look past it */ |
1663 | next_line = strchr(pos, '\n'); |
1664 | if (next_line) { |
1665 | *next_line = '\0'; |
1666 | next_line++; |
1667 | if (*next_line == '\0') |
1668 | next_line = NULL; |
1669 | } |
1670 | |
1671 | err = sscanf(pos, "%9s %lld %lu", clock, |
1672 | &off->val.tv_sec, &off->val.tv_nsec); |
1673 | if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC) |
1674 | goto out; |
1675 | |
1676 | clock[sizeof(clock) - 1] = 0; |
1677 | if (strcmp(clock, "monotonic") == 0 || |
1678 | strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0) |
1679 | off->clockid = CLOCK_MONOTONIC; |
1680 | else if (strcmp(clock, "boottime") == 0 || |
1681 | strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0) |
1682 | off->clockid = CLOCK_BOOTTIME; |
1683 | else |
1684 | goto out; |
1685 | |
1686 | noffsets++; |
1687 | if (noffsets == ARRAY_SIZE(offsets)) { |
1688 | if (next_line) |
1689 | count = next_line - kbuf; |
1690 | break; |
1691 | } |
1692 | } |
1693 | |
1694 | ret = -ESRCH; |
1695 | p = get_proc_task(inode); |
1696 | if (!p) |
1697 | goto out; |
1698 | ret = proc_timens_set_offset(file, p, offsets, n: noffsets); |
1699 | put_task_struct(t: p); |
1700 | if (ret) |
1701 | goto out; |
1702 | |
1703 | ret = count; |
1704 | out: |
1705 | kfree(objp: kbuf); |
1706 | return ret; |
1707 | } |
1708 | |
1709 | static int timens_offsets_open(struct inode *inode, struct file *filp) |
1710 | { |
1711 | return single_open(filp, timens_offsets_show, inode); |
1712 | } |
1713 | |
1714 | static const struct file_operations proc_timens_offsets_operations = { |
1715 | .open = timens_offsets_open, |
1716 | .read = seq_read, |
1717 | .write = timens_offsets_write, |
1718 | .llseek = seq_lseek, |
1719 | .release = single_release, |
1720 | }; |
1721 | #endif /* CONFIG_TIME_NS */ |
1722 | |
1723 | static ssize_t comm_write(struct file *file, const char __user *buf, |
1724 | size_t count, loff_t *offset) |
1725 | { |
1726 | struct inode *inode = file_inode(f: file); |
1727 | struct task_struct *p; |
1728 | char buffer[TASK_COMM_LEN] = {}; |
1729 | const size_t maxlen = sizeof(buffer) - 1; |
1730 | |
1731 | if (copy_from_user(to: buffer, from: buf, n: count > maxlen ? maxlen : count)) |
1732 | return -EFAULT; |
1733 | |
1734 | p = get_proc_task(inode); |
1735 | if (!p) |
1736 | return -ESRCH; |
1737 | |
1738 | if (same_thread_group(current, p2: p)) { |
1739 | set_task_comm(p, buffer); |
1740 | proc_comm_connector(task: p); |
1741 | } |
1742 | else |
1743 | count = -EINVAL; |
1744 | |
1745 | put_task_struct(t: p); |
1746 | |
1747 | return count; |
1748 | } |
1749 | |
1750 | static int comm_show(struct seq_file *m, void *v) |
1751 | { |
1752 | struct inode *inode = m->private; |
1753 | struct task_struct *p; |
1754 | |
1755 | p = get_proc_task(inode); |
1756 | if (!p) |
1757 | return -ESRCH; |
1758 | |
1759 | proc_task_name(m, p, escape: false); |
1760 | seq_putc(m, c: '\n'); |
1761 | |
1762 | put_task_struct(t: p); |
1763 | |
1764 | return 0; |
1765 | } |
1766 | |
1767 | static int comm_open(struct inode *inode, struct file *filp) |
1768 | { |
1769 | return single_open(filp, comm_show, inode); |
1770 | } |
1771 | |
1772 | static const struct file_operations proc_pid_set_comm_operations = { |
1773 | .open = comm_open, |
1774 | .read = seq_read, |
1775 | .write = comm_write, |
1776 | .llseek = seq_lseek, |
1777 | .release = single_release, |
1778 | }; |
1779 | |
1780 | static int proc_exe_link(struct dentry *dentry, struct path *exe_path) |
1781 | { |
1782 | struct task_struct *task; |
1783 | struct file *exe_file; |
1784 | |
1785 | task = get_proc_task(inode: d_inode(dentry)); |
1786 | if (!task) |
1787 | return -ENOENT; |
1788 | exe_file = get_task_exe_file(task); |
1789 | put_task_struct(t: task); |
1790 | if (exe_file) { |
1791 | *exe_path = exe_file->f_path; |
1792 | path_get(&exe_file->f_path); |
1793 | fput(exe_file); |
1794 | return 0; |
1795 | } else |
1796 | return -ENOENT; |
1797 | } |
1798 | |
1799 | static const char *proc_pid_get_link(struct dentry *dentry, |
1800 | struct inode *inode, |
1801 | struct delayed_call *done) |
1802 | { |
1803 | struct path path; |
1804 | int error = -EACCES; |
1805 | |
1806 | if (!dentry) |
1807 | return ERR_PTR(error: -ECHILD); |
1808 | |
1809 | /* Are we allowed to snoop on the tasks file descriptors? */ |
1810 | if (!proc_fd_access_allowed(inode)) |
1811 | goto out; |
1812 | |
1813 | error = PROC_I(inode)->op.proc_get_link(dentry, &path); |
1814 | if (error) |
1815 | goto out; |
1816 | |
1817 | error = nd_jump_link(path: &path); |
1818 | out: |
1819 | return ERR_PTR(error); |
1820 | } |
1821 | |
1822 | static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen) |
1823 | { |
1824 | char *tmp = kmalloc(PATH_MAX, GFP_KERNEL); |
1825 | char *pathname; |
1826 | int len; |
1827 | |
1828 | if (!tmp) |
1829 | return -ENOMEM; |
1830 | |
1831 | pathname = d_path(path, tmp, PATH_MAX); |
1832 | len = PTR_ERR(ptr: pathname); |
1833 | if (IS_ERR(ptr: pathname)) |
1834 | goto out; |
1835 | len = tmp + PATH_MAX - 1 - pathname; |
1836 | |
1837 | if (len > buflen) |
1838 | len = buflen; |
1839 | if (copy_to_user(to: buffer, from: pathname, n: len)) |
1840 | len = -EFAULT; |
1841 | out: |
1842 | kfree(objp: tmp); |
1843 | return len; |
1844 | } |
1845 | |
1846 | static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) |
1847 | { |
1848 | int error = -EACCES; |
1849 | struct inode *inode = d_inode(dentry); |
1850 | struct path path; |
1851 | |
1852 | /* Are we allowed to snoop on the tasks file descriptors? */ |
1853 | if (!proc_fd_access_allowed(inode)) |
1854 | goto out; |
1855 | |
1856 | error = PROC_I(inode)->op.proc_get_link(dentry, &path); |
1857 | if (error) |
1858 | goto out; |
1859 | |
1860 | error = do_proc_readlink(path: &path, buffer, buflen); |
1861 | path_put(&path); |
1862 | out: |
1863 | return error; |
1864 | } |
1865 | |
1866 | const struct inode_operations proc_pid_link_inode_operations = { |
1867 | .readlink = proc_pid_readlink, |
1868 | .get_link = proc_pid_get_link, |
1869 | .setattr = proc_setattr, |
1870 | }; |
1871 | |
1872 | |
1873 | /* building an inode */ |
1874 | |
1875 | void task_dump_owner(struct task_struct *task, umode_t mode, |
1876 | kuid_t *ruid, kgid_t *rgid) |
1877 | { |
1878 | /* Depending on the state of dumpable compute who should own a |
1879 | * proc file for a task. |
1880 | */ |
1881 | const struct cred *cred; |
1882 | kuid_t uid; |
1883 | kgid_t gid; |
1884 | |
1885 | if (unlikely(task->flags & PF_KTHREAD)) { |
1886 | *ruid = GLOBAL_ROOT_UID; |
1887 | *rgid = GLOBAL_ROOT_GID; |
1888 | return; |
1889 | } |
1890 | |
1891 | /* Default to the tasks effective ownership */ |
1892 | rcu_read_lock(); |
1893 | cred = __task_cred(task); |
1894 | uid = cred->euid; |
1895 | gid = cred->egid; |
1896 | rcu_read_unlock(); |
1897 | |
1898 | /* |
1899 | * Before the /proc/pid/status file was created the only way to read |
1900 | * the effective uid of a /process was to stat /proc/pid. Reading |
1901 | * /proc/pid/status is slow enough that procps and other packages |
1902 | * kept stating /proc/pid. To keep the rules in /proc simple I have |
1903 | * made this apply to all per process world readable and executable |
1904 | * directories. |
1905 | */ |
1906 | if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { |
1907 | struct mm_struct *mm; |
1908 | task_lock(task); |
1909 | mm = task->mm; |
1910 | /* Make non-dumpable tasks owned by some root */ |
1911 | if (mm) { |
1912 | if (get_dumpable(mm) != SUID_DUMP_USER) { |
1913 | struct user_namespace *user_ns = mm->user_ns; |
1914 | |
1915 | uid = make_kuid(user_ns, 0); |
1916 | if (!uid_valid(uid)) |
1917 | uid = GLOBAL_ROOT_UID; |
1918 | |
1919 | gid = make_kgid(user_ns, 0); |
1920 | if (!gid_valid(gid)) |
1921 | gid = GLOBAL_ROOT_GID; |
1922 | } |
1923 | } else { |
1924 | uid = GLOBAL_ROOT_UID; |
1925 | gid = GLOBAL_ROOT_GID; |
1926 | } |
1927 | task_unlock(task); |
1928 | } |
1929 | *ruid = uid; |
1930 | *rgid = gid; |
1931 | } |
1932 | |
1933 | void proc_pid_evict_inode(struct proc_inode *ei) |
1934 | { |
1935 | struct pid *pid = ei->pid; |
1936 | |
1937 | if (S_ISDIR(ei->vfs_inode.i_mode)) { |
1938 | spin_lock(lock: &pid->lock); |
1939 | hlist_del_init_rcu(n: &ei->sibling_inodes); |
1940 | spin_unlock(lock: &pid->lock); |
1941 | } |
1942 | } |
1943 | |
1944 | struct inode *proc_pid_make_inode(struct super_block *sb, |
1945 | struct task_struct *task, umode_t mode) |
1946 | { |
1947 | struct inode * inode; |
1948 | struct proc_inode *ei; |
1949 | struct pid *pid; |
1950 | |
1951 | /* We need a new inode */ |
1952 | |
1953 | inode = new_inode(sb); |
1954 | if (!inode) |
1955 | goto out; |
1956 | |
1957 | /* Common stuff */ |
1958 | ei = PROC_I(inode); |
1959 | inode->i_mode = mode; |
1960 | inode->i_ino = get_next_ino(); |
1961 | simple_inode_init_ts(inode); |
1962 | inode->i_op = &proc_def_inode_operations; |
1963 | |
1964 | /* |
1965 | * grab the reference to task. |
1966 | */ |
1967 | pid = get_task_pid(task, type: PIDTYPE_PID); |
1968 | if (!pid) |
1969 | goto out_unlock; |
1970 | |
1971 | /* Let the pid remember us for quick removal */ |
1972 | ei->pid = pid; |
1973 | |
1974 | task_dump_owner(task, mode: 0, ruid: &inode->i_uid, rgid: &inode->i_gid); |
1975 | security_task_to_inode(p: task, inode); |
1976 | |
1977 | out: |
1978 | return inode; |
1979 | |
1980 | out_unlock: |
1981 | iput(inode); |
1982 | return NULL; |
1983 | } |
1984 | |
1985 | /* |
1986 | * Generating an inode and adding it into @pid->inodes, so that task will |
1987 | * invalidate inode's dentry before being released. |
1988 | * |
1989 | * This helper is used for creating dir-type entries under '/proc' and |
1990 | * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>' |
1991 | * can be released by invalidating '/proc/<tgid>' dentry. |
1992 | * In theory, dentries under '/proc/<tgid>/task' can also be released by |
1993 | * invalidating '/proc/<tgid>' dentry, we reserve it to handle single |
1994 | * thread exiting situation: Any one of threads should invalidate its |
1995 | * '/proc/<tgid>/task/<pid>' dentry before released. |
1996 | */ |
1997 | static struct inode *proc_pid_make_base_inode(struct super_block *sb, |
1998 | struct task_struct *task, umode_t mode) |
1999 | { |
2000 | struct inode *inode; |
2001 | struct proc_inode *ei; |
2002 | struct pid *pid; |
2003 | |
2004 | inode = proc_pid_make_inode(sb, task, mode); |
2005 | if (!inode) |
2006 | return NULL; |
2007 | |
2008 | /* Let proc_flush_pid find this directory inode */ |
2009 | ei = PROC_I(inode); |
2010 | pid = ei->pid; |
2011 | spin_lock(lock: &pid->lock); |
2012 | hlist_add_head_rcu(n: &ei->sibling_inodes, h: &pid->inodes); |
2013 | spin_unlock(lock: &pid->lock); |
2014 | |
2015 | return inode; |
2016 | } |
2017 | |
2018 | int pid_getattr(struct mnt_idmap *idmap, const struct path *path, |
2019 | struct kstat *stat, u32 request_mask, unsigned int query_flags) |
2020 | { |
2021 | struct inode *inode = d_inode(dentry: path->dentry); |
2022 | struct proc_fs_info *fs_info = proc_sb_info(sb: inode->i_sb); |
2023 | struct task_struct *task; |
2024 | |
2025 | generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); |
2026 | |
2027 | stat->uid = GLOBAL_ROOT_UID; |
2028 | stat->gid = GLOBAL_ROOT_GID; |
2029 | rcu_read_lock(); |
2030 | task = pid_task(proc_pid(inode), PIDTYPE_PID); |
2031 | if (task) { |
2032 | if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) { |
2033 | rcu_read_unlock(); |
2034 | /* |
2035 | * This doesn't prevent learning whether PID exists, |
2036 | * it only makes getattr() consistent with readdir(). |
2037 | */ |
2038 | return -ENOENT; |
2039 | } |
2040 | task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); |
2041 | } |
2042 | rcu_read_unlock(); |
2043 | return 0; |
2044 | } |
2045 | |
2046 | /* dentry stuff */ |
2047 | |
2048 | /* |
2049 | * Set <pid>/... inode ownership (can change due to setuid(), etc.) |
2050 | */ |
2051 | void pid_update_inode(struct task_struct *task, struct inode *inode) |
2052 | { |
2053 | task_dump_owner(task, mode: inode->i_mode, ruid: &inode->i_uid, rgid: &inode->i_gid); |
2054 | |
2055 | inode->i_mode &= ~(S_ISUID | S_ISGID); |
2056 | security_task_to_inode(p: task, inode); |
2057 | } |
2058 | |
2059 | /* |
2060 | * Rewrite the inode's ownerships here because the owning task may have |
2061 | * performed a setuid(), etc. |
2062 | * |
2063 | */ |
2064 | static int pid_revalidate(struct inode *dir, const struct qstr *name, |
2065 | struct dentry *dentry, unsigned int flags) |
2066 | { |
2067 | struct inode *inode; |
2068 | struct task_struct *task; |
2069 | int ret = 0; |
2070 | |
2071 | rcu_read_lock(); |
2072 | inode = d_inode_rcu(dentry); |
2073 | if (!inode) |
2074 | goto out; |
2075 | task = pid_task(pid: proc_pid(inode), PIDTYPE_PID); |
2076 | |
2077 | if (task) { |
2078 | pid_update_inode(task, inode); |
2079 | ret = 1; |
2080 | } |
2081 | out: |
2082 | rcu_read_unlock(); |
2083 | return ret; |
2084 | } |
2085 | |
2086 | static inline bool proc_inode_is_dead(struct inode *inode) |
2087 | { |
2088 | return !proc_pid(inode)->tasks[PIDTYPE_PID].first; |
2089 | } |
2090 | |
2091 | int pid_delete_dentry(const struct dentry *dentry) |
2092 | { |
2093 | /* Is the task we represent dead? |
2094 | * If so, then don't put the dentry on the lru list, |
2095 | * kill it immediately. |
2096 | */ |
2097 | return proc_inode_is_dead(inode: d_inode(dentry)); |
2098 | } |
2099 | |
2100 | const struct dentry_operations pid_dentry_operations = |
2101 | { |
2102 | .d_revalidate = pid_revalidate, |
2103 | .d_delete = pid_delete_dentry, |
2104 | }; |
2105 | |
2106 | /* Lookups */ |
2107 | |
2108 | /* |
2109 | * Fill a directory entry. |
2110 | * |
2111 | * If possible create the dcache entry and derive our inode number and |
2112 | * file type from dcache entry. |
2113 | * |
2114 | * Since all of the proc inode numbers are dynamically generated, the inode |
2115 | * numbers do not exist until the inode is cache. This means creating |
2116 | * the dcache entry in readdir is necessary to keep the inode numbers |
2117 | * reported by readdir in sync with the inode numbers reported |
2118 | * by stat. |
2119 | */ |
2120 | bool proc_fill_cache(struct file *file, struct dir_context *ctx, |
2121 | const char *name, unsigned int len, |
2122 | instantiate_t instantiate, struct task_struct *task, const void *ptr) |
2123 | { |
2124 | struct dentry *child, *dir = file->f_path.dentry; |
2125 | struct qstr qname = QSTR_INIT(name, len); |
2126 | struct inode *inode; |
2127 | unsigned type = DT_UNKNOWN; |
2128 | ino_t ino = 1; |
2129 | |
2130 | child = try_lookup_noperm(&qname, dir); |
2131 | if (!child) { |
2132 | DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); |
2133 | child = d_alloc_parallel(dir, &qname, &wq); |
2134 | if (IS_ERR(ptr: child)) |
2135 | goto end_instantiate; |
2136 | if (d_in_lookup(dentry: child)) { |
2137 | struct dentry *res; |
2138 | res = instantiate(child, task, ptr); |
2139 | d_lookup_done(dentry: child); |
2140 | if (unlikely(res)) { |
2141 | dput(child); |
2142 | child = res; |
2143 | if (IS_ERR(ptr: child)) |
2144 | goto end_instantiate; |
2145 | } |
2146 | } |
2147 | } |
2148 | inode = d_inode(dentry: child); |
2149 | ino = inode->i_ino; |
2150 | type = inode->i_mode >> 12; |
2151 | dput(child); |
2152 | end_instantiate: |
2153 | return dir_emit(ctx, name, namelen: len, ino, type); |
2154 | } |
2155 | |
2156 | /* |
2157 | * dname_to_vma_addr - maps a dentry name into two unsigned longs |
2158 | * which represent vma start and end addresses. |
2159 | */ |
2160 | static int dname_to_vma_addr(struct dentry *dentry, |
2161 | unsigned long *start, unsigned long *end) |
2162 | { |
2163 | const char *str = dentry->d_name.name; |
2164 | unsigned long long sval, eval; |
2165 | unsigned int len; |
2166 | |
2167 | if (str[0] == '0' && str[1] != '-') |
2168 | return -EINVAL; |
2169 | len = _parse_integer(s: str, base: 16, res: &sval); |
2170 | if (len & KSTRTOX_OVERFLOW) |
2171 | return -EINVAL; |
2172 | if (sval != (unsigned long)sval) |
2173 | return -EINVAL; |
2174 | str += len; |
2175 | |
2176 | if (*str != '-') |
2177 | return -EINVAL; |
2178 | str++; |
2179 | |
2180 | if (str[0] == '0' && str[1]) |
2181 | return -EINVAL; |
2182 | len = _parse_integer(s: str, base: 16, res: &eval); |
2183 | if (len & KSTRTOX_OVERFLOW) |
2184 | return -EINVAL; |
2185 | if (eval != (unsigned long)eval) |
2186 | return -EINVAL; |
2187 | str += len; |
2188 | |
2189 | if (*str != '\0') |
2190 | return -EINVAL; |
2191 | |
2192 | *start = sval; |
2193 | *end = eval; |
2194 | |
2195 | return 0; |
2196 | } |
2197 | |
2198 | static int map_files_d_revalidate(struct inode *dir, const struct qstr *name, |
2199 | struct dentry *dentry, unsigned int flags) |
2200 | { |
2201 | unsigned long vm_start, vm_end; |
2202 | bool exact_vma_exists = false; |
2203 | struct mm_struct *mm = NULL; |
2204 | struct task_struct *task; |
2205 | struct inode *inode; |
2206 | int status = 0; |
2207 | |
2208 | if (flags & LOOKUP_RCU) |
2209 | return -ECHILD; |
2210 | |
2211 | inode = d_inode(dentry); |
2212 | task = get_proc_task(inode); |
2213 | if (!task) |
2214 | goto out_notask; |
2215 | |
2216 | mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); |
2217 | if (IS_ERR(ptr: mm)) |
2218 | goto out; |
2219 | |
2220 | if (!dname_to_vma_addr(dentry, start: &vm_start, end: &vm_end)) { |
2221 | status = mmap_read_lock_killable(mm); |
2222 | if (!status) { |
2223 | exact_vma_exists = !!find_exact_vma(mm, vm_start, |
2224 | vm_end); |
2225 | mmap_read_unlock(mm); |
2226 | } |
2227 | } |
2228 | |
2229 | mmput(mm); |
2230 | |
2231 | if (exact_vma_exists) { |
2232 | task_dump_owner(task, mode: 0, ruid: &inode->i_uid, rgid: &inode->i_gid); |
2233 | |
2234 | security_task_to_inode(p: task, inode); |
2235 | status = 1; |
2236 | } |
2237 | |
2238 | out: |
2239 | put_task_struct(t: task); |
2240 | |
2241 | out_notask: |
2242 | return status; |
2243 | } |
2244 | |
2245 | static const struct dentry_operations tid_map_files_dentry_operations = { |
2246 | .d_revalidate = map_files_d_revalidate, |
2247 | .d_delete = pid_delete_dentry, |
2248 | }; |
2249 | |
2250 | static int map_files_get_link(struct dentry *dentry, struct path *path) |
2251 | { |
2252 | unsigned long vm_start, vm_end; |
2253 | struct vm_area_struct *vma; |
2254 | struct task_struct *task; |
2255 | struct mm_struct *mm; |
2256 | int rc; |
2257 | |
2258 | rc = -ENOENT; |
2259 | task = get_proc_task(inode: d_inode(dentry)); |
2260 | if (!task) |
2261 | goto out; |
2262 | |
2263 | mm = get_task_mm(task); |
2264 | put_task_struct(t: task); |
2265 | if (!mm) |
2266 | goto out; |
2267 | |
2268 | rc = dname_to_vma_addr(dentry, start: &vm_start, end: &vm_end); |
2269 | if (rc) |
2270 | goto out_mmput; |
2271 | |
2272 | rc = mmap_read_lock_killable(mm); |
2273 | if (rc) |
2274 | goto out_mmput; |
2275 | |
2276 | rc = -ENOENT; |
2277 | vma = find_exact_vma(mm, vm_start, vm_end); |
2278 | if (vma && vma->vm_file) { |
2279 | *path = *file_user_path(f: vma->vm_file); |
2280 | path_get(path); |
2281 | rc = 0; |
2282 | } |
2283 | mmap_read_unlock(mm); |
2284 | |
2285 | out_mmput: |
2286 | mmput(mm); |
2287 | out: |
2288 | return rc; |
2289 | } |
2290 | |
2291 | struct map_files_info { |
2292 | unsigned long start; |
2293 | unsigned long end; |
2294 | fmode_t mode; |
2295 | }; |
2296 | |
2297 | /* |
2298 | * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due |
2299 | * to concerns about how the symlinks may be used to bypass permissions on |
2300 | * ancestor directories in the path to the file in question. |
2301 | */ |
2302 | static const char * |
2303 | proc_map_files_get_link(struct dentry *dentry, |
2304 | struct inode *inode, |
2305 | struct delayed_call *done) |
2306 | { |
2307 | if (!checkpoint_restore_ns_capable(ns: &init_user_ns)) |
2308 | return ERR_PTR(error: -EPERM); |
2309 | |
2310 | return proc_pid_get_link(dentry, inode, done); |
2311 | } |
2312 | |
2313 | /* |
2314 | * Identical to proc_pid_link_inode_operations except for get_link() |
2315 | */ |
2316 | static const struct inode_operations proc_map_files_link_inode_operations = { |
2317 | .readlink = proc_pid_readlink, |
2318 | .get_link = proc_map_files_get_link, |
2319 | .setattr = proc_setattr, |
2320 | }; |
2321 | |
2322 | static struct dentry * |
2323 | proc_map_files_instantiate(struct dentry *dentry, |
2324 | struct task_struct *task, const void *ptr) |
2325 | { |
2326 | fmode_t mode = (fmode_t)(unsigned long)ptr; |
2327 | struct proc_inode *ei; |
2328 | struct inode *inode; |
2329 | |
2330 | inode = proc_pid_make_inode(sb: dentry->d_sb, task, S_IFLNK | |
2331 | ((mode & FMODE_READ ) ? S_IRUSR : 0) | |
2332 | ((mode & FMODE_WRITE) ? S_IWUSR : 0)); |
2333 | if (!inode) |
2334 | return ERR_PTR(error: -ENOENT); |
2335 | |
2336 | ei = PROC_I(inode); |
2337 | ei->op.proc_get_link = map_files_get_link; |
2338 | |
2339 | inode->i_op = &proc_map_files_link_inode_operations; |
2340 | inode->i_size = 64; |
2341 | |
2342 | return proc_splice_unmountable(inode, dentry, |
2343 | d_ops: &tid_map_files_dentry_operations); |
2344 | } |
2345 | |
2346 | static struct dentry *proc_map_files_lookup(struct inode *dir, |
2347 | struct dentry *dentry, unsigned int flags) |
2348 | { |
2349 | unsigned long vm_start, vm_end; |
2350 | struct vm_area_struct *vma; |
2351 | struct task_struct *task; |
2352 | struct dentry *result; |
2353 | struct mm_struct *mm; |
2354 | |
2355 | result = ERR_PTR(error: -ENOENT); |
2356 | task = get_proc_task(inode: dir); |
2357 | if (!task) |
2358 | goto out; |
2359 | |
2360 | result = ERR_PTR(error: -EACCES); |
2361 | if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
2362 | goto out_put_task; |
2363 | |
2364 | result = ERR_PTR(error: -ENOENT); |
2365 | if (dname_to_vma_addr(dentry, start: &vm_start, end: &vm_end)) |
2366 | goto out_put_task; |
2367 | |
2368 | mm = get_task_mm(task); |
2369 | if (!mm) |
2370 | goto out_put_task; |
2371 | |
2372 | result = ERR_PTR(error: -EINTR); |
2373 | if (mmap_read_lock_killable(mm)) |
2374 | goto out_put_mm; |
2375 | |
2376 | result = ERR_PTR(error: -ENOENT); |
2377 | vma = find_exact_vma(mm, vm_start, vm_end); |
2378 | if (!vma) |
2379 | goto out_no_vma; |
2380 | |
2381 | if (vma->vm_file) |
2382 | result = proc_map_files_instantiate(dentry, task, |
2383 | ptr: (void *)(unsigned long)vma->vm_file->f_mode); |
2384 | |
2385 | out_no_vma: |
2386 | mmap_read_unlock(mm); |
2387 | out_put_mm: |
2388 | mmput(mm); |
2389 | out_put_task: |
2390 | put_task_struct(t: task); |
2391 | out: |
2392 | return result; |
2393 | } |
2394 | |
2395 | static const struct inode_operations proc_map_files_inode_operations = { |
2396 | .lookup = proc_map_files_lookup, |
2397 | .permission = proc_fd_permission, |
2398 | .setattr = proc_setattr, |
2399 | }; |
2400 | |
2401 | static int |
2402 | proc_map_files_readdir(struct file *file, struct dir_context *ctx) |
2403 | { |
2404 | struct vm_area_struct *vma; |
2405 | struct task_struct *task; |
2406 | struct mm_struct *mm; |
2407 | unsigned long nr_files, pos, i; |
2408 | GENRADIX(struct map_files_info) fa; |
2409 | struct map_files_info *p; |
2410 | int ret; |
2411 | struct vma_iterator vmi; |
2412 | |
2413 | genradix_init(&fa); |
2414 | |
2415 | ret = -ENOENT; |
2416 | task = get_proc_task(inode: file_inode(f: file)); |
2417 | if (!task) |
2418 | goto out; |
2419 | |
2420 | ret = -EACCES; |
2421 | if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
2422 | goto out_put_task; |
2423 | |
2424 | ret = 0; |
2425 | if (!dir_emit_dots(file, ctx)) |
2426 | goto out_put_task; |
2427 | |
2428 | mm = get_task_mm(task); |
2429 | if (!mm) |
2430 | goto out_put_task; |
2431 | |
2432 | ret = mmap_read_lock_killable(mm); |
2433 | if (ret) { |
2434 | mmput(mm); |
2435 | goto out_put_task; |
2436 | } |
2437 | |
2438 | nr_files = 0; |
2439 | |
2440 | /* |
2441 | * We need two passes here: |
2442 | * |
2443 | * 1) Collect vmas of mapped files with mmap_lock taken |
2444 | * 2) Release mmap_lock and instantiate entries |
2445 | * |
2446 | * otherwise we get lockdep complained, since filldir() |
2447 | * routine might require mmap_lock taken in might_fault(). |
2448 | */ |
2449 | |
2450 | pos = 2; |
2451 | vma_iter_init(vmi: &vmi, mm, addr: 0); |
2452 | for_each_vma(vmi, vma) { |
2453 | if (!vma->vm_file) |
2454 | continue; |
2455 | if (++pos <= ctx->pos) |
2456 | continue; |
2457 | |
2458 | p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL); |
2459 | if (!p) { |
2460 | ret = -ENOMEM; |
2461 | mmap_read_unlock(mm); |
2462 | mmput(mm); |
2463 | goto out_put_task; |
2464 | } |
2465 | |
2466 | p->start = vma->vm_start; |
2467 | p->end = vma->vm_end; |
2468 | p->mode = vma->vm_file->f_mode; |
2469 | } |
2470 | mmap_read_unlock(mm); |
2471 | mmput(mm); |
2472 | |
2473 | for (i = 0; i < nr_files; i++) { |
2474 | char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */ |
2475 | unsigned int len; |
2476 | |
2477 | p = genradix_ptr(&fa, i); |
2478 | len = snprintf(buf, size: sizeof(buf), fmt: "%lx-%lx", p->start, p->end); |
2479 | if (!proc_fill_cache(file, ctx, |
2480 | name: buf, len, |
2481 | instantiate: proc_map_files_instantiate, |
2482 | task, |
2483 | ptr: (void *)(unsigned long)p->mode)) |
2484 | break; |
2485 | ctx->pos++; |
2486 | } |
2487 | |
2488 | out_put_task: |
2489 | put_task_struct(t: task); |
2490 | out: |
2491 | genradix_free(&fa); |
2492 | return ret; |
2493 | } |
2494 | |
2495 | static const struct file_operations proc_map_files_operations = { |
2496 | .read = generic_read_dir, |
2497 | .iterate_shared = proc_map_files_readdir, |
2498 | .llseek = generic_file_llseek, |
2499 | }; |
2500 | |
2501 | #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) |
2502 | struct timers_private { |
2503 | struct pid *pid; |
2504 | struct task_struct *task; |
2505 | struct pid_namespace *ns; |
2506 | }; |
2507 | |
2508 | static void *timers_start(struct seq_file *m, loff_t *pos) |
2509 | { |
2510 | struct timers_private *tp = m->private; |
2511 | |
2512 | tp->task = get_pid_task(pid: tp->pid, PIDTYPE_PID); |
2513 | if (!tp->task) |
2514 | return ERR_PTR(error: -ESRCH); |
2515 | |
2516 | rcu_read_lock(); |
2517 | return seq_hlist_start_rcu(head: &tp->task->signal->posix_timers, pos: *pos); |
2518 | } |
2519 | |
2520 | static void *timers_next(struct seq_file *m, void *v, loff_t *pos) |
2521 | { |
2522 | struct timers_private *tp = m->private; |
2523 | |
2524 | return seq_hlist_next_rcu(v, head: &tp->task->signal->posix_timers, ppos: pos); |
2525 | } |
2526 | |
2527 | static void timers_stop(struct seq_file *m, void *v) |
2528 | { |
2529 | struct timers_private *tp = m->private; |
2530 | |
2531 | if (tp->task) { |
2532 | put_task_struct(t: tp->task); |
2533 | tp->task = NULL; |
2534 | rcu_read_unlock(); |
2535 | } |
2536 | } |
2537 | |
2538 | static int show_timer(struct seq_file *m, void *v) |
2539 | { |
2540 | static const char * const nstr[] = { |
2541 | [SIGEV_SIGNAL] = "signal", |
2542 | [SIGEV_NONE] = "none", |
2543 | [SIGEV_THREAD] = "thread", |
2544 | }; |
2545 | |
2546 | struct k_itimer *timer = hlist_entry((struct hlist_node *)v, struct k_itimer, list); |
2547 | struct timers_private *tp = m->private; |
2548 | int notify = timer->it_sigev_notify; |
2549 | |
2550 | guard(spinlock_irq)(l: &timer->it_lock); |
2551 | if (!posixtimer_valid(timer)) |
2552 | return 0; |
2553 | |
2554 | seq_printf(m, fmt: "ID: %d\n", timer->it_id); |
2555 | seq_printf(m, fmt: "signal: %d/%px\n", timer->sigq.info.si_signo, |
2556 | timer->sigq.info.si_value.sival_ptr); |
2557 | seq_printf(m, fmt: "notify: %s/%s.%d\n", nstr[notify & ~SIGEV_THREAD_ID], |
2558 | (notify & SIGEV_THREAD_ID) ? "tid": "pid", |
2559 | pid_nr_ns(pid: timer->it_pid, ns: tp->ns)); |
2560 | seq_printf(m, fmt: "ClockID: %d\n", timer->it_clock); |
2561 | |
2562 | return 0; |
2563 | } |
2564 | |
2565 | static const struct seq_operations proc_timers_seq_ops = { |
2566 | .start = timers_start, |
2567 | .next = timers_next, |
2568 | .stop = timers_stop, |
2569 | .show = show_timer, |
2570 | }; |
2571 | |
2572 | static int proc_timers_open(struct inode *inode, struct file *file) |
2573 | { |
2574 | struct timers_private *tp; |
2575 | |
2576 | tp = __seq_open_private(file, &proc_timers_seq_ops, |
2577 | sizeof(struct timers_private)); |
2578 | if (!tp) |
2579 | return -ENOMEM; |
2580 | |
2581 | tp->pid = proc_pid(inode); |
2582 | tp->ns = proc_pid_ns(sb: inode->i_sb); |
2583 | return 0; |
2584 | } |
2585 | |
2586 | static const struct file_operations proc_timers_operations = { |
2587 | .open = proc_timers_open, |
2588 | .read = seq_read, |
2589 | .llseek = seq_lseek, |
2590 | .release = seq_release_private, |
2591 | }; |
2592 | #endif |
2593 | |
2594 | static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, |
2595 | size_t count, loff_t *offset) |
2596 | { |
2597 | struct inode *inode = file_inode(f: file); |
2598 | struct task_struct *p; |
2599 | u64 slack_ns; |
2600 | int err; |
2601 | |
2602 | err = kstrtoull_from_user(s: buf, count, base: 10, res: &slack_ns); |
2603 | if (err < 0) |
2604 | return err; |
2605 | |
2606 | p = get_proc_task(inode); |
2607 | if (!p) |
2608 | return -ESRCH; |
2609 | |
2610 | if (p != current) { |
2611 | rcu_read_lock(); |
2612 | if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { |
2613 | rcu_read_unlock(); |
2614 | count = -EPERM; |
2615 | goto out; |
2616 | } |
2617 | rcu_read_unlock(); |
2618 | |
2619 | err = security_task_setscheduler(p); |
2620 | if (err) { |
2621 | count = err; |
2622 | goto out; |
2623 | } |
2624 | } |
2625 | |
2626 | task_lock(p); |
2627 | if (rt_or_dl_task_policy(tsk: p)) |
2628 | slack_ns = 0; |
2629 | else if (slack_ns == 0) |
2630 | slack_ns = p->default_timer_slack_ns; |
2631 | p->timer_slack_ns = slack_ns; |
2632 | task_unlock(p); |
2633 | |
2634 | out: |
2635 | put_task_struct(t: p); |
2636 | |
2637 | return count; |
2638 | } |
2639 | |
2640 | static int timerslack_ns_show(struct seq_file *m, void *v) |
2641 | { |
2642 | struct inode *inode = m->private; |
2643 | struct task_struct *p; |
2644 | int err = 0; |
2645 | |
2646 | p = get_proc_task(inode); |
2647 | if (!p) |
2648 | return -ESRCH; |
2649 | |
2650 | if (p != current) { |
2651 | rcu_read_lock(); |
2652 | if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { |
2653 | rcu_read_unlock(); |
2654 | err = -EPERM; |
2655 | goto out; |
2656 | } |
2657 | rcu_read_unlock(); |
2658 | |
2659 | err = security_task_getscheduler(p); |
2660 | if (err) |
2661 | goto out; |
2662 | } |
2663 | |
2664 | task_lock(p); |
2665 | seq_printf(m, fmt: "%llu\n", p->timer_slack_ns); |
2666 | task_unlock(p); |
2667 | |
2668 | out: |
2669 | put_task_struct(t: p); |
2670 | |
2671 | return err; |
2672 | } |
2673 | |
2674 | static int timerslack_ns_open(struct inode *inode, struct file *filp) |
2675 | { |
2676 | return single_open(filp, timerslack_ns_show, inode); |
2677 | } |
2678 | |
2679 | static const struct file_operations proc_pid_set_timerslack_ns_operations = { |
2680 | .open = timerslack_ns_open, |
2681 | .read = seq_read, |
2682 | .write = timerslack_ns_write, |
2683 | .llseek = seq_lseek, |
2684 | .release = single_release, |
2685 | }; |
2686 | |
2687 | static struct dentry *proc_pident_instantiate(struct dentry *dentry, |
2688 | struct task_struct *task, const void *ptr) |
2689 | { |
2690 | const struct pid_entry *p = ptr; |
2691 | struct inode *inode; |
2692 | struct proc_inode *ei; |
2693 | |
2694 | inode = proc_pid_make_inode(sb: dentry->d_sb, task, mode: p->mode); |
2695 | if (!inode) |
2696 | return ERR_PTR(error: -ENOENT); |
2697 | |
2698 | ei = PROC_I(inode); |
2699 | if (S_ISDIR(inode->i_mode)) |
2700 | set_nlink(inode, nlink: 2); /* Use getattr to fix if necessary */ |
2701 | if (p->iop) |
2702 | inode->i_op = p->iop; |
2703 | if (p->fop) |
2704 | inode->i_fop = p->fop; |
2705 | ei->op = p->op; |
2706 | pid_update_inode(task, inode); |
2707 | d_set_d_op(dentry, op: &pid_dentry_operations); |
2708 | return d_splice_alias(inode, dentry); |
2709 | } |
2710 | |
2711 | static struct dentry *proc_pident_lookup(struct inode *dir, |
2712 | struct dentry *dentry, |
2713 | const struct pid_entry *p, |
2714 | const struct pid_entry *end) |
2715 | { |
2716 | struct task_struct *task = get_proc_task(inode: dir); |
2717 | struct dentry *res = ERR_PTR(error: -ENOENT); |
2718 | |
2719 | if (!task) |
2720 | goto out_no_task; |
2721 | |
2722 | /* |
2723 | * Yes, it does not scale. And it should not. Don't add |
2724 | * new entries into /proc/<tgid>/ without very good reasons. |
2725 | */ |
2726 | for (; p < end; p++) { |
2727 | if (p->len != dentry->d_name.len) |
2728 | continue; |
2729 | if (!memcmp(p: dentry->d_name.name, q: p->name, size: p->len)) { |
2730 | res = proc_pident_instantiate(dentry, task, ptr: p); |
2731 | break; |
2732 | } |
2733 | } |
2734 | put_task_struct(t: task); |
2735 | out_no_task: |
2736 | return res; |
2737 | } |
2738 | |
2739 | static int proc_pident_readdir(struct file *file, struct dir_context *ctx, |
2740 | const struct pid_entry *ents, unsigned int nents) |
2741 | { |
2742 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
2743 | const struct pid_entry *p; |
2744 | |
2745 | if (!task) |
2746 | return -ENOENT; |
2747 | |
2748 | if (!dir_emit_dots(file, ctx)) |
2749 | goto out; |
2750 | |
2751 | if (ctx->pos >= nents + 2) |
2752 | goto out; |
2753 | |
2754 | for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { |
2755 | if (!proc_fill_cache(file, ctx, name: p->name, len: p->len, |
2756 | instantiate: proc_pident_instantiate, task, ptr: p)) |
2757 | break; |
2758 | ctx->pos++; |
2759 | } |
2760 | out: |
2761 | put_task_struct(t: task); |
2762 | return 0; |
2763 | } |
2764 | |
2765 | #ifdef CONFIG_SECURITY |
2766 | static int proc_pid_attr_open(struct inode *inode, struct file *file) |
2767 | { |
2768 | file->private_data = NULL; |
2769 | __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); |
2770 | return 0; |
2771 | } |
2772 | |
2773 | static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, |
2774 | size_t count, loff_t *ppos) |
2775 | { |
2776 | struct inode * inode = file_inode(f: file); |
2777 | char *p = NULL; |
2778 | ssize_t length; |
2779 | struct task_struct *task = get_proc_task(inode); |
2780 | |
2781 | if (!task) |
2782 | return -ESRCH; |
2783 | |
2784 | length = security_getprocattr(p: task, lsmid: PROC_I(inode)->op.lsmid, |
2785 | name: file->f_path.dentry->d_name.name, |
2786 | value: &p); |
2787 | put_task_struct(t: task); |
2788 | if (length > 0) |
2789 | length = simple_read_from_buffer(to: buf, count, ppos, from: p, available: length); |
2790 | kfree(objp: p); |
2791 | return length; |
2792 | } |
2793 | |
2794 | static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, |
2795 | size_t count, loff_t *ppos) |
2796 | { |
2797 | struct inode * inode = file_inode(f: file); |
2798 | struct task_struct *task; |
2799 | void *page; |
2800 | int rv; |
2801 | |
2802 | /* A task may only write when it was the opener. */ |
2803 | if (file->private_data != current->mm) |
2804 | return -EPERM; |
2805 | |
2806 | rcu_read_lock(); |
2807 | task = pid_task(pid: proc_pid(inode), PIDTYPE_PID); |
2808 | if (!task) { |
2809 | rcu_read_unlock(); |
2810 | return -ESRCH; |
2811 | } |
2812 | /* A task may only write its own attributes. */ |
2813 | if (current != task) { |
2814 | rcu_read_unlock(); |
2815 | return -EACCES; |
2816 | } |
2817 | /* Prevent changes to overridden credentials. */ |
2818 | if (current_cred() != current_real_cred()) { |
2819 | rcu_read_unlock(); |
2820 | return -EBUSY; |
2821 | } |
2822 | rcu_read_unlock(); |
2823 | |
2824 | if (count > PAGE_SIZE) |
2825 | count = PAGE_SIZE; |
2826 | |
2827 | /* No partial writes. */ |
2828 | if (*ppos != 0) |
2829 | return -EINVAL; |
2830 | |
2831 | page = memdup_user(buf, count); |
2832 | if (IS_ERR(ptr: page)) { |
2833 | rv = PTR_ERR(ptr: page); |
2834 | goto out; |
2835 | } |
2836 | |
2837 | /* Guard against adverse ptrace interaction */ |
2838 | rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); |
2839 | if (rv < 0) |
2840 | goto out_free; |
2841 | |
2842 | rv = security_setprocattr(lsmid: PROC_I(inode)->op.lsmid, |
2843 | name: file->f_path.dentry->d_name.name, value: page, |
2844 | size: count); |
2845 | mutex_unlock(lock: ¤t->signal->cred_guard_mutex); |
2846 | out_free: |
2847 | kfree(objp: page); |
2848 | out: |
2849 | return rv; |
2850 | } |
2851 | |
2852 | static const struct file_operations proc_pid_attr_operations = { |
2853 | .open = proc_pid_attr_open, |
2854 | .read = proc_pid_attr_read, |
2855 | .write = proc_pid_attr_write, |
2856 | .llseek = generic_file_llseek, |
2857 | .release = mem_release, |
2858 | }; |
2859 | |
2860 | #define LSM_DIR_OPS(LSM) \ |
2861 | static int proc_##LSM##_attr_dir_iterate(struct file *filp, \ |
2862 | struct dir_context *ctx) \ |
2863 | { \ |
2864 | return proc_pident_readdir(filp, ctx, \ |
2865 | LSM##_attr_dir_stuff, \ |
2866 | ARRAY_SIZE(LSM##_attr_dir_stuff)); \ |
2867 | } \ |
2868 | \ |
2869 | static const struct file_operations proc_##LSM##_attr_dir_ops = { \ |
2870 | .read = generic_read_dir, \ |
2871 | .iterate_shared = proc_##LSM##_attr_dir_iterate, \ |
2872 | .llseek = default_llseek, \ |
2873 | }; \ |
2874 | \ |
2875 | static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \ |
2876 | struct dentry *dentry, unsigned int flags) \ |
2877 | { \ |
2878 | return proc_pident_lookup(dir, dentry, \ |
2879 | LSM##_attr_dir_stuff, \ |
2880 | LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \ |
2881 | } \ |
2882 | \ |
2883 | static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \ |
2884 | .lookup = proc_##LSM##_attr_dir_lookup, \ |
2885 | .getattr = pid_getattr, \ |
2886 | .setattr = proc_setattr, \ |
2887 | } |
2888 | |
2889 | #ifdef CONFIG_SECURITY_SMACK |
2890 | static const struct pid_entry smack_attr_dir_stuff[] = { |
2891 | ATTR(LSM_ID_SMACK, "current", 0666), |
2892 | }; |
2893 | LSM_DIR_OPS(smack); |
2894 | #endif |
2895 | |
2896 | #ifdef CONFIG_SECURITY_APPARMOR |
2897 | static const struct pid_entry apparmor_attr_dir_stuff[] = { |
2898 | ATTR(LSM_ID_APPARMOR, "current", 0666), |
2899 | ATTR(LSM_ID_APPARMOR, "prev", 0444), |
2900 | ATTR(LSM_ID_APPARMOR, "exec", 0666), |
2901 | }; |
2902 | LSM_DIR_OPS(apparmor); |
2903 | #endif |
2904 | |
2905 | static const struct pid_entry attr_dir_stuff[] = { |
2906 | ATTR(LSM_ID_UNDEF, "current", 0666), |
2907 | ATTR(LSM_ID_UNDEF, "prev", 0444), |
2908 | ATTR(LSM_ID_UNDEF, "exec", 0666), |
2909 | ATTR(LSM_ID_UNDEF, "fscreate", 0666), |
2910 | ATTR(LSM_ID_UNDEF, "keycreate", 0666), |
2911 | ATTR(LSM_ID_UNDEF, "sockcreate", 0666), |
2912 | #ifdef CONFIG_SECURITY_SMACK |
2913 | DIR("smack", 0555, |
2914 | proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops), |
2915 | #endif |
2916 | #ifdef CONFIG_SECURITY_APPARMOR |
2917 | DIR("apparmor", 0555, |
2918 | proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops), |
2919 | #endif |
2920 | }; |
2921 | |
2922 | static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) |
2923 | { |
2924 | return proc_pident_readdir(file, ctx, |
2925 | ents: attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); |
2926 | } |
2927 | |
2928 | static const struct file_operations proc_attr_dir_operations = { |
2929 | .read = generic_read_dir, |
2930 | .iterate_shared = proc_attr_dir_readdir, |
2931 | .llseek = generic_file_llseek, |
2932 | }; |
2933 | |
2934 | static struct dentry *proc_attr_dir_lookup(struct inode *dir, |
2935 | struct dentry *dentry, unsigned int flags) |
2936 | { |
2937 | return proc_pident_lookup(dir, dentry, |
2938 | p: attr_dir_stuff, |
2939 | end: attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff)); |
2940 | } |
2941 | |
2942 | static const struct inode_operations proc_attr_dir_inode_operations = { |
2943 | .lookup = proc_attr_dir_lookup, |
2944 | .getattr = pid_getattr, |
2945 | .setattr = proc_setattr, |
2946 | }; |
2947 | |
2948 | #endif |
2949 | |
2950 | #ifdef CONFIG_ELF_CORE |
2951 | static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, |
2952 | size_t count, loff_t *ppos) |
2953 | { |
2954 | struct task_struct *task = get_proc_task(inode: file_inode(f: file)); |
2955 | struct mm_struct *mm; |
2956 | char buffer[PROC_NUMBUF]; |
2957 | size_t len; |
2958 | int ret; |
2959 | |
2960 | if (!task) |
2961 | return -ESRCH; |
2962 | |
2963 | ret = 0; |
2964 | mm = get_task_mm(task); |
2965 | if (mm) { |
2966 | len = snprintf(buf: buffer, size: sizeof(buffer), fmt: "%08lx\n", |
2967 | ((mm->flags & MMF_DUMP_FILTER_MASK) >> |
2968 | MMF_DUMP_FILTER_SHIFT)); |
2969 | mmput(mm); |
2970 | ret = simple_read_from_buffer(to: buf, count, ppos, from: buffer, available: len); |
2971 | } |
2972 | |
2973 | put_task_struct(t: task); |
2974 | |
2975 | return ret; |
2976 | } |
2977 | |
2978 | static ssize_t proc_coredump_filter_write(struct file *file, |
2979 | const char __user *buf, |
2980 | size_t count, |
2981 | loff_t *ppos) |
2982 | { |
2983 | struct task_struct *task; |
2984 | struct mm_struct *mm; |
2985 | unsigned int val; |
2986 | int ret; |
2987 | int i; |
2988 | unsigned long mask; |
2989 | |
2990 | ret = kstrtouint_from_user(s: buf, count, base: 0, res: &val); |
2991 | if (ret < 0) |
2992 | return ret; |
2993 | |
2994 | ret = -ESRCH; |
2995 | task = get_proc_task(inode: file_inode(f: file)); |
2996 | if (!task) |
2997 | goto out_no_task; |
2998 | |
2999 | mm = get_task_mm(task); |
3000 | if (!mm) |
3001 | goto out_no_mm; |
3002 | ret = 0; |
3003 | |
3004 | for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { |
3005 | if (val & mask) |
3006 | set_bit(nr: i + MMF_DUMP_FILTER_SHIFT, addr: &mm->flags); |
3007 | else |
3008 | clear_bit(nr: i + MMF_DUMP_FILTER_SHIFT, addr: &mm->flags); |
3009 | } |
3010 | |
3011 | mmput(mm); |
3012 | out_no_mm: |
3013 | put_task_struct(t: task); |
3014 | out_no_task: |
3015 | if (ret < 0) |
3016 | return ret; |
3017 | return count; |
3018 | } |
3019 | |
3020 | static const struct file_operations proc_coredump_filter_operations = { |
3021 | .read = proc_coredump_filter_read, |
3022 | .write = proc_coredump_filter_write, |
3023 | .llseek = generic_file_llseek, |
3024 | }; |
3025 | #endif |
3026 | |
3027 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
3028 | static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) |
3029 | { |
3030 | struct task_io_accounting acct; |
3031 | int result; |
3032 | |
3033 | result = down_read_killable(sem: &task->signal->exec_update_lock); |
3034 | if (result) |
3035 | return result; |
3036 | |
3037 | if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { |
3038 | result = -EACCES; |
3039 | goto out_unlock; |
3040 | } |
3041 | |
3042 | if (whole) { |
3043 | struct signal_struct *sig = task->signal; |
3044 | struct task_struct *t; |
3045 | unsigned int seq = 1; |
3046 | unsigned long flags; |
3047 | |
3048 | rcu_read_lock(); |
3049 | do { |
3050 | seq++; /* 2 on the 1st/lockless path, otherwise odd */ |
3051 | flags = read_seqbegin_or_lock_irqsave(lock: &sig->stats_lock, seq: &seq); |
3052 | |
3053 | acct = sig->ioac; |
3054 | __for_each_thread(sig, t) |
3055 | task_io_accounting_add(dst: &acct, src: &t->ioac); |
3056 | |
3057 | } while (need_seqretry(lock: &sig->stats_lock, seq)); |
3058 | done_seqretry_irqrestore(lock: &sig->stats_lock, seq, flags); |
3059 | rcu_read_unlock(); |
3060 | } else { |
3061 | acct = task->ioac; |
3062 | } |
3063 | |
3064 | seq_printf(m, |
3065 | fmt: "rchar: %llu\n" |
3066 | "wchar: %llu\n" |
3067 | "syscr: %llu\n" |
3068 | "syscw: %llu\n" |
3069 | "read_bytes: %llu\n" |
3070 | "write_bytes: %llu\n" |
3071 | "cancelled_write_bytes: %llu\n", |
3072 | (unsigned long long)acct.rchar, |
3073 | (unsigned long long)acct.wchar, |
3074 | (unsigned long long)acct.syscr, |
3075 | (unsigned long long)acct.syscw, |
3076 | (unsigned long long)acct.read_bytes, |
3077 | (unsigned long long)acct.write_bytes, |
3078 | (unsigned long long)acct.cancelled_write_bytes); |
3079 | result = 0; |
3080 | |
3081 | out_unlock: |
3082 | up_read(sem: &task->signal->exec_update_lock); |
3083 | return result; |
3084 | } |
3085 | |
3086 | static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, |
3087 | struct pid *pid, struct task_struct *task) |
3088 | { |
3089 | return do_io_accounting(task, m, whole: 0); |
3090 | } |
3091 | |
3092 | static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, |
3093 | struct pid *pid, struct task_struct *task) |
3094 | { |
3095 | return do_io_accounting(task, m, whole: 1); |
3096 | } |
3097 | #endif /* CONFIG_TASK_IO_ACCOUNTING */ |
3098 | |
3099 | #ifdef CONFIG_USER_NS |
3100 | static int proc_id_map_open(struct inode *inode, struct file *file, |
3101 | const struct seq_operations *seq_ops) |
3102 | { |
3103 | struct user_namespace *ns = NULL; |
3104 | struct task_struct *task; |
3105 | struct seq_file *seq; |
3106 | int ret = -EINVAL; |
3107 | |
3108 | task = get_proc_task(inode); |
3109 | if (task) { |
3110 | rcu_read_lock(); |
3111 | ns = get_user_ns(task_cred_xxx(task, user_ns)); |
3112 | rcu_read_unlock(); |
3113 | put_task_struct(t: task); |
3114 | } |
3115 | if (!ns) |
3116 | goto err; |
3117 | |
3118 | ret = seq_open(file, seq_ops); |
3119 | if (ret) |
3120 | goto err_put_ns; |
3121 | |
3122 | seq = file->private_data; |
3123 | seq->private = ns; |
3124 | |
3125 | return 0; |
3126 | err_put_ns: |
3127 | put_user_ns(ns); |
3128 | err: |
3129 | return ret; |
3130 | } |
3131 | |
3132 | static int proc_id_map_release(struct inode *inode, struct file *file) |
3133 | { |
3134 | struct seq_file *seq = file->private_data; |
3135 | struct user_namespace *ns = seq->private; |
3136 | put_user_ns(ns); |
3137 | return seq_release(inode, file); |
3138 | } |
3139 | |
3140 | static int proc_uid_map_open(struct inode *inode, struct file *file) |
3141 | { |
3142 | return proc_id_map_open(inode, file, seq_ops: &proc_uid_seq_operations); |
3143 | } |
3144 | |
3145 | static int proc_gid_map_open(struct inode *inode, struct file *file) |
3146 | { |
3147 | return proc_id_map_open(inode, file, seq_ops: &proc_gid_seq_operations); |
3148 | } |
3149 | |
3150 | static int proc_projid_map_open(struct inode *inode, struct file *file) |
3151 | { |
3152 | return proc_id_map_open(inode, file, seq_ops: &proc_projid_seq_operations); |
3153 | } |
3154 | |
3155 | static const struct file_operations proc_uid_map_operations = { |
3156 | .open = proc_uid_map_open, |
3157 | .write = proc_uid_map_write, |
3158 | .read = seq_read, |
3159 | .llseek = seq_lseek, |
3160 | .release = proc_id_map_release, |
3161 | }; |
3162 | |
3163 | static const struct file_operations proc_gid_map_operations = { |
3164 | .open = proc_gid_map_open, |
3165 | .write = proc_gid_map_write, |
3166 | .read = seq_read, |
3167 | .llseek = seq_lseek, |
3168 | .release = proc_id_map_release, |
3169 | }; |
3170 | |
3171 | static const struct file_operations proc_projid_map_operations = { |
3172 | .open = proc_projid_map_open, |
3173 | .write = proc_projid_map_write, |
3174 | .read = seq_read, |
3175 | .llseek = seq_lseek, |
3176 | .release = proc_id_map_release, |
3177 | }; |
3178 | |
3179 | static int proc_setgroups_open(struct inode *inode, struct file *file) |
3180 | { |
3181 | struct user_namespace *ns = NULL; |
3182 | struct task_struct *task; |
3183 | int ret; |
3184 | |
3185 | ret = -ESRCH; |
3186 | task = get_proc_task(inode); |
3187 | if (task) { |
3188 | rcu_read_lock(); |
3189 | ns = get_user_ns(task_cred_xxx(task, user_ns)); |
3190 | rcu_read_unlock(); |
3191 | put_task_struct(t: task); |
3192 | } |
3193 | if (!ns) |
3194 | goto err; |
3195 | |
3196 | if (file->f_mode & FMODE_WRITE) { |
3197 | ret = -EACCES; |
3198 | if (!ns_capable(ns, CAP_SYS_ADMIN)) |
3199 | goto err_put_ns; |
3200 | } |
3201 | |
3202 | ret = single_open(file, &proc_setgroups_show, ns); |
3203 | if (ret) |
3204 | goto err_put_ns; |
3205 | |
3206 | return 0; |
3207 | err_put_ns: |
3208 | put_user_ns(ns); |
3209 | err: |
3210 | return ret; |
3211 | } |
3212 | |
3213 | static int proc_setgroups_release(struct inode *inode, struct file *file) |
3214 | { |
3215 | struct seq_file *seq = file->private_data; |
3216 | struct user_namespace *ns = seq->private; |
3217 | int ret = single_release(inode, file); |
3218 | put_user_ns(ns); |
3219 | return ret; |
3220 | } |
3221 | |
3222 | static const struct file_operations proc_setgroups_operations = { |
3223 | .open = proc_setgroups_open, |
3224 | .write = proc_setgroups_write, |
3225 | .read = seq_read, |
3226 | .llseek = seq_lseek, |
3227 | .release = proc_setgroups_release, |
3228 | }; |
3229 | #endif /* CONFIG_USER_NS */ |
3230 | |
3231 | static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, |
3232 | struct pid *pid, struct task_struct *task) |
3233 | { |
3234 | int err = lock_trace(task); |
3235 | if (!err) { |
3236 | seq_printf(m, fmt: "%08x\n", task->personality); |
3237 | unlock_trace(task); |
3238 | } |
3239 | return err; |
3240 | } |
3241 | |
3242 | #ifdef CONFIG_LIVEPATCH |
3243 | static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, |
3244 | struct pid *pid, struct task_struct *task) |
3245 | { |
3246 | seq_printf(m, "%d\n", task->patch_state); |
3247 | return 0; |
3248 | } |
3249 | #endif /* CONFIG_LIVEPATCH */ |
3250 | |
3251 | #ifdef CONFIG_KSM |
3252 | static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns, |
3253 | struct pid *pid, struct task_struct *task) |
3254 | { |
3255 | struct mm_struct *mm; |
3256 | |
3257 | mm = get_task_mm(task); |
3258 | if (mm) { |
3259 | seq_printf(m, fmt: "%lu\n", mm->ksm_merging_pages); |
3260 | mmput(mm); |
3261 | } |
3262 | |
3263 | return 0; |
3264 | } |
3265 | static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, |
3266 | struct pid *pid, struct task_struct *task) |
3267 | { |
3268 | struct mm_struct *mm; |
3269 | int ret = 0; |
3270 | |
3271 | mm = get_task_mm(task); |
3272 | if (mm) { |
3273 | seq_printf(m, fmt: "ksm_rmap_items %lu\n", mm->ksm_rmap_items); |
3274 | seq_printf(m, fmt: "ksm_zero_pages %ld\n", mm_ksm_zero_pages(mm)); |
3275 | seq_printf(m, fmt: "ksm_merging_pages %lu\n", mm->ksm_merging_pages); |
3276 | seq_printf(m, fmt: "ksm_process_profit %ld\n", ksm_process_profit(mm)); |
3277 | seq_printf(m, fmt: "ksm_merge_any: %s\n", |
3278 | test_bit(MMF_VM_MERGE_ANY, &mm->flags) ? "yes": "no"); |
3279 | ret = mmap_read_lock_killable(mm); |
3280 | if (ret) { |
3281 | mmput(mm); |
3282 | return ret; |
3283 | } |
3284 | seq_printf(m, fmt: "ksm_mergeable: %s\n", |
3285 | ksm_process_mergeable(mm) ? "yes": "no"); |
3286 | mmap_read_unlock(mm); |
3287 | mmput(mm); |
3288 | } |
3289 | |
3290 | return 0; |
3291 | } |
3292 | #endif /* CONFIG_KSM */ |
3293 | |
3294 | #ifdef CONFIG_STACKLEAK_METRICS |
3295 | static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns, |
3296 | struct pid *pid, struct task_struct *task) |
3297 | { |
3298 | unsigned long prev_depth = THREAD_SIZE - |
3299 | (task->prev_lowest_stack & (THREAD_SIZE - 1)); |
3300 | unsigned long depth = THREAD_SIZE - |
3301 | (task->lowest_stack & (THREAD_SIZE - 1)); |
3302 | |
3303 | seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n", |
3304 | prev_depth, depth); |
3305 | return 0; |
3306 | } |
3307 | #endif /* CONFIG_STACKLEAK_METRICS */ |
3308 | |
3309 | /* |
3310 | * Thread groups |
3311 | */ |
3312 | static const struct file_operations proc_task_operations; |
3313 | static const struct inode_operations proc_task_inode_operations; |
3314 | |
3315 | static const struct pid_entry tgid_base_stuff[] = { |
3316 | DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), |
3317 | DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), |
3318 | DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), |
3319 | DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations), |
3320 | DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), |
3321 | #ifdef CONFIG_NET |
3322 | DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), |
3323 | #endif |
3324 | REG("environ", S_IRUSR, proc_environ_operations), |
3325 | REG("auxv", S_IRUSR, proc_auxv_operations), |
3326 | ONE("status", S_IRUGO, proc_pid_status), |
3327 | ONE("personality", S_IRUSR, proc_pid_personality), |
3328 | ONE("limits", S_IRUGO, proc_pid_limits), |
3329 | REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), |
3330 | #ifdef CONFIG_SCHED_AUTOGROUP |
3331 | REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), |
3332 | #endif |
3333 | #ifdef CONFIG_TIME_NS |
3334 | REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations), |
3335 | #endif |
3336 | REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), |
3337 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
3338 | ONE("syscall", S_IRUSR, proc_pid_syscall), |
3339 | #endif |
3340 | REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), |
3341 | ONE("stat", S_IRUGO, proc_tgid_stat), |
3342 | ONE("statm", S_IRUGO, proc_pid_statm), |
3343 | REG("maps", S_IRUGO, proc_pid_maps_operations), |
3344 | #ifdef CONFIG_NUMA |
3345 | REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), |
3346 | #endif |
3347 | REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), |
3348 | LNK("cwd", proc_cwd_link), |
3349 | LNK("root", proc_root_link), |
3350 | LNK("exe", proc_exe_link), |
3351 | REG("mounts", S_IRUGO, proc_mounts_operations), |
3352 | REG("mountinfo", S_IRUGO, proc_mountinfo_operations), |
3353 | REG("mountstats", S_IRUSR, proc_mountstats_operations), |
3354 | #ifdef CONFIG_PROC_PAGE_MONITOR |
3355 | REG("clear_refs", S_IWUSR, proc_clear_refs_operations), |
3356 | REG("smaps", S_IRUGO, proc_pid_smaps_operations), |
3357 | REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), |
3358 | REG("pagemap", S_IRUSR, proc_pagemap_operations), |
3359 | #endif |
3360 | #ifdef CONFIG_SECURITY |
3361 | DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), |
3362 | #endif |
3363 | #ifdef CONFIG_KALLSYMS |
3364 | ONE("wchan", S_IRUGO, proc_pid_wchan), |
3365 | #endif |
3366 | #ifdef CONFIG_STACKTRACE |
3367 | ONE("stack", S_IRUSR, proc_pid_stack), |
3368 | #endif |
3369 | #ifdef CONFIG_SCHED_INFO |
3370 | ONE("schedstat", S_IRUGO, proc_pid_schedstat), |
3371 | #endif |
3372 | #ifdef CONFIG_LATENCYTOP |
3373 | REG("latency", S_IRUGO, proc_lstats_operations), |
3374 | #endif |
3375 | #ifdef CONFIG_PROC_PID_CPUSET |
3376 | ONE("cpuset", S_IRUGO, proc_cpuset_show), |
3377 | #endif |
3378 | #ifdef CONFIG_CGROUPS |
3379 | ONE("cgroup", S_IRUGO, proc_cgroup_show), |
3380 | #endif |
3381 | #ifdef CONFIG_PROC_CPU_RESCTRL |
3382 | ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show), |
3383 | #endif |
3384 | ONE("oom_score", S_IRUGO, proc_oom_score), |
3385 | REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), |
3386 | REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), |
3387 | #ifdef CONFIG_AUDIT |
3388 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), |
3389 | REG("sessionid", S_IRUGO, proc_sessionid_operations), |
3390 | #endif |
3391 | #ifdef CONFIG_FAULT_INJECTION |
3392 | REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), |
3393 | REG("fail-nth", 0644, proc_fail_nth_operations), |
3394 | #endif |
3395 | #ifdef CONFIG_ELF_CORE |
3396 | REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), |
3397 | #endif |
3398 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
3399 | ONE("io", S_IRUSR, proc_tgid_io_accounting), |
3400 | #endif |
3401 | #ifdef CONFIG_USER_NS |
3402 | REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), |
3403 | REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), |
3404 | REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), |
3405 | REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), |
3406 | #endif |
3407 | #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) |
3408 | REG("timers", S_IRUGO, proc_timers_operations), |
3409 | #endif |
3410 | REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), |
3411 | #ifdef CONFIG_LIVEPATCH |
3412 | ONE("patch_state", S_IRUSR, proc_pid_patch_state), |
3413 | #endif |
3414 | #ifdef CONFIG_STACKLEAK_METRICS |
3415 | ONE("stack_depth", S_IRUGO, proc_stack_depth), |
3416 | #endif |
3417 | #ifdef CONFIG_PROC_PID_ARCH_STATUS |
3418 | ONE("arch_status", S_IRUGO, proc_pid_arch_status), |
3419 | #endif |
3420 | #ifdef CONFIG_SECCOMP_CACHE_DEBUG |
3421 | ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), |
3422 | #endif |
3423 | #ifdef CONFIG_KSM |
3424 | ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages), |
3425 | ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat), |
3426 | #endif |
3427 | }; |
3428 | |
3429 | static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) |
3430 | { |
3431 | return proc_pident_readdir(file, ctx, |
3432 | ents: tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); |
3433 | } |
3434 | |
3435 | static const struct file_operations proc_tgid_base_operations = { |
3436 | .read = generic_read_dir, |
3437 | .iterate_shared = proc_tgid_base_readdir, |
3438 | .llseek = generic_file_llseek, |
3439 | }; |
3440 | |
3441 | struct pid *tgid_pidfd_to_pid(const struct file *file) |
3442 | { |
3443 | if (file->f_op != &proc_tgid_base_operations) |
3444 | return ERR_PTR(error: -EBADF); |
3445 | |
3446 | return proc_pid(inode: file_inode(f: file)); |
3447 | } |
3448 | |
3449 | static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
3450 | { |
3451 | return proc_pident_lookup(dir, dentry, |
3452 | p: tgid_base_stuff, |
3453 | end: tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff)); |
3454 | } |
3455 | |
3456 | static const struct inode_operations proc_tgid_base_inode_operations = { |
3457 | .lookup = proc_tgid_base_lookup, |
3458 | .getattr = pid_getattr, |
3459 | .setattr = proc_setattr, |
3460 | .permission = proc_pid_permission, |
3461 | }; |
3462 | |
3463 | /** |
3464 | * proc_flush_pid - Remove dcache entries for @pid from the /proc dcache. |
3465 | * @pid: pid that should be flushed. |
3466 | * |
3467 | * This function walks a list of inodes (that belong to any proc |
3468 | * filesystem) that are attached to the pid and flushes them from |
3469 | * the dentry cache. |
3470 | * |
3471 | * It is safe and reasonable to cache /proc entries for a task until |
3472 | * that task exits. After that they just clog up the dcache with |
3473 | * useless entries, possibly causing useful dcache entries to be |
3474 | * flushed instead. This routine is provided to flush those useless |
3475 | * dcache entries when a process is reaped. |
3476 | * |
3477 | * NOTE: This routine is just an optimization so it does not guarantee |
3478 | * that no dcache entries will exist after a process is reaped |
3479 | * it just makes it very unlikely that any will persist. |
3480 | */ |
3481 | |
3482 | void proc_flush_pid(struct pid *pid) |
3483 | { |
3484 | proc_invalidate_siblings_dcache(inodes: &pid->inodes, lock: &pid->lock); |
3485 | } |
3486 | |
3487 | static struct dentry *proc_pid_instantiate(struct dentry * dentry, |
3488 | struct task_struct *task, const void *ptr) |
3489 | { |
3490 | struct inode *inode; |
3491 | |
3492 | inode = proc_pid_make_base_inode(sb: dentry->d_sb, task, |
3493 | S_IFDIR | S_IRUGO | S_IXUGO); |
3494 | if (!inode) |
3495 | return ERR_PTR(error: -ENOENT); |
3496 | |
3497 | inode->i_op = &proc_tgid_base_inode_operations; |
3498 | inode->i_fop = &proc_tgid_base_operations; |
3499 | inode->i_flags|=S_IMMUTABLE; |
3500 | |
3501 | set_nlink(inode, nlink: nlink_tgid); |
3502 | pid_update_inode(task, inode); |
3503 | |
3504 | d_set_d_op(dentry, op: &pid_dentry_operations); |
3505 | return d_splice_alias(inode, dentry); |
3506 | } |
3507 | |
3508 | struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags) |
3509 | { |
3510 | struct task_struct *task; |
3511 | unsigned tgid; |
3512 | struct proc_fs_info *fs_info; |
3513 | struct pid_namespace *ns; |
3514 | struct dentry *result = ERR_PTR(error: -ENOENT); |
3515 | |
3516 | tgid = name_to_int(qstr: &dentry->d_name); |
3517 | if (tgid == ~0U) |
3518 | goto out; |
3519 | |
3520 | fs_info = proc_sb_info(sb: dentry->d_sb); |
3521 | ns = fs_info->pid_ns; |
3522 | rcu_read_lock(); |
3523 | task = find_task_by_pid_ns(nr: tgid, ns); |
3524 | if (task) |
3525 | get_task_struct(t: task); |
3526 | rcu_read_unlock(); |
3527 | if (!task) |
3528 | goto out; |
3529 | |
3530 | /* Limit procfs to only ptraceable tasks */ |
3531 | if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) { |
3532 | if (!has_pid_permissions(fs_info, task, hide_pid_min: HIDEPID_NO_ACCESS)) |
3533 | goto out_put_task; |
3534 | } |
3535 | |
3536 | result = proc_pid_instantiate(dentry, task, NULL); |
3537 | out_put_task: |
3538 | put_task_struct(t: task); |
3539 | out: |
3540 | return result; |
3541 | } |
3542 | |
3543 | /* |
3544 | * Find the first task with tgid >= tgid |
3545 | * |
3546 | */ |
3547 | struct tgid_iter { |
3548 | unsigned int tgid; |
3549 | struct task_struct *task; |
3550 | }; |
3551 | static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) |
3552 | { |
3553 | struct pid *pid; |
3554 | |
3555 | if (iter.task) |
3556 | put_task_struct(t: iter.task); |
3557 | rcu_read_lock(); |
3558 | retry: |
3559 | iter.task = NULL; |
3560 | pid = find_ge_pid(nr: iter.tgid, ns); |
3561 | if (pid) { |
3562 | iter.tgid = pid_nr_ns(pid, ns); |
3563 | iter.task = pid_task(pid, PIDTYPE_TGID); |
3564 | if (!iter.task) { |
3565 | iter.tgid += 1; |
3566 | goto retry; |
3567 | } |
3568 | get_task_struct(t: iter.task); |
3569 | } |
3570 | rcu_read_unlock(); |
3571 | return iter; |
3572 | } |
3573 | |
3574 | #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) |
3575 | |
3576 | /* for the /proc/ directory itself, after non-process stuff has been done */ |
3577 | int proc_pid_readdir(struct file *file, struct dir_context *ctx) |
3578 | { |
3579 | struct tgid_iter iter; |
3580 | struct proc_fs_info *fs_info = proc_sb_info(sb: file_inode(f: file)->i_sb); |
3581 | struct pid_namespace *ns = proc_pid_ns(sb: file_inode(f: file)->i_sb); |
3582 | loff_t pos = ctx->pos; |
3583 | |
3584 | if (pos >= PID_MAX_LIMIT + TGID_OFFSET) |
3585 | return 0; |
3586 | |
3587 | if (pos == TGID_OFFSET - 2) { |
3588 | struct inode *inode = d_inode(dentry: fs_info->proc_self); |
3589 | if (!dir_emit(ctx, name: "self", namelen: 4, ino: inode->i_ino, DT_LNK)) |
3590 | return 0; |
3591 | ctx->pos = pos = pos + 1; |
3592 | } |
3593 | if (pos == TGID_OFFSET - 1) { |
3594 | struct inode *inode = d_inode(dentry: fs_info->proc_thread_self); |
3595 | if (!dir_emit(ctx, name: "thread-self", namelen: 11, ino: inode->i_ino, DT_LNK)) |
3596 | return 0; |
3597 | ctx->pos = pos = pos + 1; |
3598 | } |
3599 | iter.tgid = pos - TGID_OFFSET; |
3600 | iter.task = NULL; |
3601 | for (iter = next_tgid(ns, iter); |
3602 | iter.task; |
3603 | iter.tgid += 1, iter = next_tgid(ns, iter)) { |
3604 | char name[10 + 1]; |
3605 | unsigned int len; |
3606 | |
3607 | cond_resched(); |
3608 | if (!has_pid_permissions(fs_info, task: iter.task, hide_pid_min: HIDEPID_INVISIBLE)) |
3609 | continue; |
3610 | |
3611 | len = snprintf(buf: name, size: sizeof(name), fmt: "%u", iter.tgid); |
3612 | ctx->pos = iter.tgid + TGID_OFFSET; |
3613 | if (!proc_fill_cache(file, ctx, name, len, |
3614 | instantiate: proc_pid_instantiate, task: iter.task, NULL)) { |
3615 | put_task_struct(t: iter.task); |
3616 | return 0; |
3617 | } |
3618 | } |
3619 | ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; |
3620 | return 0; |
3621 | } |
3622 | |
3623 | /* |
3624 | * proc_tid_comm_permission is a special permission function exclusively |
3625 | * used for the node /proc/<pid>/task/<tid>/comm. |
3626 | * It bypasses generic permission checks in the case where a task of the same |
3627 | * task group attempts to access the node. |
3628 | * The rationale behind this is that glibc and bionic access this node for |
3629 | * cross thread naming (pthread_set/getname_np(!self)). However, if |
3630 | * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, |
3631 | * which locks out the cross thread naming implementation. |
3632 | * This function makes sure that the node is always accessible for members of |
3633 | * same thread group. |
3634 | */ |
3635 | static int proc_tid_comm_permission(struct mnt_idmap *idmap, |
3636 | struct inode *inode, int mask) |
3637 | { |
3638 | bool is_same_tgroup; |
3639 | struct task_struct *task; |
3640 | |
3641 | task = get_proc_task(inode); |
3642 | if (!task) |
3643 | return -ESRCH; |
3644 | is_same_tgroup = same_thread_group(current, p2: task); |
3645 | put_task_struct(t: task); |
3646 | |
3647 | if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { |
3648 | /* This file (/proc/<pid>/task/<tid>/comm) can always be |
3649 | * read or written by the members of the corresponding |
3650 | * thread group. |
3651 | */ |
3652 | return 0; |
3653 | } |
3654 | |
3655 | return generic_permission(&nop_mnt_idmap, inode, mask); |
3656 | } |
3657 | |
3658 | static const struct inode_operations proc_tid_comm_inode_operations = { |
3659 | .setattr = proc_setattr, |
3660 | .permission = proc_tid_comm_permission, |
3661 | }; |
3662 | |
3663 | /* |
3664 | * Tasks |
3665 | */ |
3666 | static const struct pid_entry tid_base_stuff[] = { |
3667 | DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), |
3668 | DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations), |
3669 | DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), |
3670 | #ifdef CONFIG_NET |
3671 | DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), |
3672 | #endif |
3673 | REG("environ", S_IRUSR, proc_environ_operations), |
3674 | REG("auxv", S_IRUSR, proc_auxv_operations), |
3675 | ONE("status", S_IRUGO, proc_pid_status), |
3676 | ONE("personality", S_IRUSR, proc_pid_personality), |
3677 | ONE("limits", S_IRUGO, proc_pid_limits), |
3678 | REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), |
3679 | NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, |
3680 | &proc_tid_comm_inode_operations, |
3681 | &proc_pid_set_comm_operations, {}), |
3682 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
3683 | ONE("syscall", S_IRUSR, proc_pid_syscall), |
3684 | #endif |
3685 | REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), |
3686 | ONE("stat", S_IRUGO, proc_tid_stat), |
3687 | ONE("statm", S_IRUGO, proc_pid_statm), |
3688 | REG("maps", S_IRUGO, proc_pid_maps_operations), |
3689 | #ifdef CONFIG_PROC_CHILDREN |
3690 | REG("children", S_IRUGO, proc_tid_children_operations), |
3691 | #endif |
3692 | #ifdef CONFIG_NUMA |
3693 | REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), |
3694 | #endif |
3695 | REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), |
3696 | LNK("cwd", proc_cwd_link), |
3697 | LNK("root", proc_root_link), |
3698 | LNK("exe", proc_exe_link), |
3699 | REG("mounts", S_IRUGO, proc_mounts_operations), |
3700 | REG("mountinfo", S_IRUGO, proc_mountinfo_operations), |
3701 | #ifdef CONFIG_PROC_PAGE_MONITOR |
3702 | REG("clear_refs", S_IWUSR, proc_clear_refs_operations), |
3703 | REG("smaps", S_IRUGO, proc_pid_smaps_operations), |
3704 | REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), |
3705 | REG("pagemap", S_IRUSR, proc_pagemap_operations), |
3706 | #endif |
3707 | #ifdef CONFIG_SECURITY |
3708 | DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), |
3709 | #endif |
3710 | #ifdef CONFIG_KALLSYMS |
3711 | ONE("wchan", S_IRUGO, proc_pid_wchan), |
3712 | #endif |
3713 | #ifdef CONFIG_STACKTRACE |
3714 | ONE("stack", S_IRUSR, proc_pid_stack), |
3715 | #endif |
3716 | #ifdef CONFIG_SCHED_INFO |
3717 | ONE("schedstat", S_IRUGO, proc_pid_schedstat), |
3718 | #endif |
3719 | #ifdef CONFIG_LATENCYTOP |
3720 | REG("latency", S_IRUGO, proc_lstats_operations), |
3721 | #endif |
3722 | #ifdef CONFIG_PROC_PID_CPUSET |
3723 | ONE("cpuset", S_IRUGO, proc_cpuset_show), |
3724 | #endif |
3725 | #ifdef CONFIG_CGROUPS |
3726 | ONE("cgroup", S_IRUGO, proc_cgroup_show), |
3727 | #endif |
3728 | #ifdef CONFIG_PROC_CPU_RESCTRL |
3729 | ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show), |
3730 | #endif |
3731 | ONE("oom_score", S_IRUGO, proc_oom_score), |
3732 | REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), |
3733 | REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), |
3734 | #ifdef CONFIG_AUDIT |
3735 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), |
3736 | REG("sessionid", S_IRUGO, proc_sessionid_operations), |
3737 | #endif |
3738 | #ifdef CONFIG_FAULT_INJECTION |
3739 | REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), |
3740 | REG("fail-nth", 0644, proc_fail_nth_operations), |
3741 | #endif |
3742 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
3743 | ONE("io", S_IRUSR, proc_tid_io_accounting), |
3744 | #endif |
3745 | #ifdef CONFIG_USER_NS |
3746 | REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), |
3747 | REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), |
3748 | REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), |
3749 | REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), |
3750 | #endif |
3751 | #ifdef CONFIG_LIVEPATCH |
3752 | ONE("patch_state", S_IRUSR, proc_pid_patch_state), |
3753 | #endif |
3754 | #ifdef CONFIG_PROC_PID_ARCH_STATUS |
3755 | ONE("arch_status", S_IRUGO, proc_pid_arch_status), |
3756 | #endif |
3757 | #ifdef CONFIG_SECCOMP_CACHE_DEBUG |
3758 | ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), |
3759 | #endif |
3760 | #ifdef CONFIG_KSM |
3761 | ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages), |
3762 | ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat), |
3763 | #endif |
3764 | }; |
3765 | |
3766 | static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) |
3767 | { |
3768 | return proc_pident_readdir(file, ctx, |
3769 | ents: tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); |
3770 | } |
3771 | |
3772 | static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
3773 | { |
3774 | return proc_pident_lookup(dir, dentry, |
3775 | p: tid_base_stuff, |
3776 | end: tid_base_stuff + ARRAY_SIZE(tid_base_stuff)); |
3777 | } |
3778 | |
3779 | static const struct file_operations proc_tid_base_operations = { |
3780 | .read = generic_read_dir, |
3781 | .iterate_shared = proc_tid_base_readdir, |
3782 | .llseek = generic_file_llseek, |
3783 | }; |
3784 | |
3785 | static const struct inode_operations proc_tid_base_inode_operations = { |
3786 | .lookup = proc_tid_base_lookup, |
3787 | .getattr = pid_getattr, |
3788 | .setattr = proc_setattr, |
3789 | }; |
3790 | |
3791 | static struct dentry *proc_task_instantiate(struct dentry *dentry, |
3792 | struct task_struct *task, const void *ptr) |
3793 | { |
3794 | struct inode *inode; |
3795 | inode = proc_pid_make_base_inode(sb: dentry->d_sb, task, |
3796 | S_IFDIR | S_IRUGO | S_IXUGO); |
3797 | if (!inode) |
3798 | return ERR_PTR(error: -ENOENT); |
3799 | |
3800 | inode->i_op = &proc_tid_base_inode_operations; |
3801 | inode->i_fop = &proc_tid_base_operations; |
3802 | inode->i_flags |= S_IMMUTABLE; |
3803 | |
3804 | set_nlink(inode, nlink: nlink_tid); |
3805 | pid_update_inode(task, inode); |
3806 | |
3807 | d_set_d_op(dentry, op: &pid_dentry_operations); |
3808 | return d_splice_alias(inode, dentry); |
3809 | } |
3810 | |
3811 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) |
3812 | { |
3813 | struct task_struct *task; |
3814 | struct task_struct *leader = get_proc_task(inode: dir); |
3815 | unsigned tid; |
3816 | struct proc_fs_info *fs_info; |
3817 | struct pid_namespace *ns; |
3818 | struct dentry *result = ERR_PTR(error: -ENOENT); |
3819 | |
3820 | if (!leader) |
3821 | goto out_no_task; |
3822 | |
3823 | tid = name_to_int(qstr: &dentry->d_name); |
3824 | if (tid == ~0U) |
3825 | goto out; |
3826 | |
3827 | fs_info = proc_sb_info(sb: dentry->d_sb); |
3828 | ns = fs_info->pid_ns; |
3829 | rcu_read_lock(); |
3830 | task = find_task_by_pid_ns(nr: tid, ns); |
3831 | if (task) |
3832 | get_task_struct(t: task); |
3833 | rcu_read_unlock(); |
3834 | if (!task) |
3835 | goto out; |
3836 | if (!same_thread_group(p1: leader, p2: task)) |
3837 | goto out_drop_task; |
3838 | |
3839 | result = proc_task_instantiate(dentry, task, NULL); |
3840 | out_drop_task: |
3841 | put_task_struct(t: task); |
3842 | out: |
3843 | put_task_struct(t: leader); |
3844 | out_no_task: |
3845 | return result; |
3846 | } |
3847 | |
3848 | /* |
3849 | * Find the first tid of a thread group to return to user space. |
3850 | * |
3851 | * Usually this is just the thread group leader, but if the users |
3852 | * buffer was too small or there was a seek into the middle of the |
3853 | * directory we have more work todo. |
3854 | * |
3855 | * In the case of a short read we start with find_task_by_pid. |
3856 | * |
3857 | * In the case of a seek we start with the leader and walk nr |
3858 | * threads past it. |
3859 | */ |
3860 | static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, |
3861 | struct pid_namespace *ns) |
3862 | { |
3863 | struct task_struct *pos, *task; |
3864 | unsigned long nr = f_pos; |
3865 | |
3866 | if (nr != f_pos) /* 32bit overflow? */ |
3867 | return NULL; |
3868 | |
3869 | rcu_read_lock(); |
3870 | task = pid_task(pid, PIDTYPE_PID); |
3871 | if (!task) |
3872 | goto fail; |
3873 | |
3874 | /* Attempt to start with the tid of a thread */ |
3875 | if (tid && nr) { |
3876 | pos = find_task_by_pid_ns(nr: tid, ns); |
3877 | if (pos && same_thread_group(p1: pos, p2: task)) |
3878 | goto found; |
3879 | } |
3880 | |
3881 | /* If nr exceeds the number of threads there is nothing todo */ |
3882 | if (nr >= get_nr_threads(task)) |
3883 | goto fail; |
3884 | |
3885 | /* If we haven't found our starting place yet start |
3886 | * with the leader and walk nr threads forward. |
3887 | */ |
3888 | for_each_thread(task, pos) { |
3889 | if (!nr--) |
3890 | goto found; |
3891 | } |
3892 | fail: |
3893 | pos = NULL; |
3894 | goto out; |
3895 | found: |
3896 | get_task_struct(t: pos); |
3897 | out: |
3898 | rcu_read_unlock(); |
3899 | return pos; |
3900 | } |
3901 | |
3902 | /* |
3903 | * Find the next thread in the thread list. |
3904 | * Return NULL if there is an error or no next thread. |
3905 | * |
3906 | * The reference to the input task_struct is released. |
3907 | */ |
3908 | static struct task_struct *next_tid(struct task_struct *start) |
3909 | { |
3910 | struct task_struct *pos = NULL; |
3911 | rcu_read_lock(); |
3912 | if (pid_alive(p: start)) { |
3913 | pos = __next_thread(p: start); |
3914 | if (pos) |
3915 | get_task_struct(t: pos); |
3916 | } |
3917 | rcu_read_unlock(); |
3918 | put_task_struct(t: start); |
3919 | return pos; |
3920 | } |
3921 | |
3922 | /* for the /proc/TGID/task/ directories */ |
3923 | static int proc_task_readdir(struct file *file, struct dir_context *ctx) |
3924 | { |
3925 | struct inode *inode = file_inode(f: file); |
3926 | struct task_struct *task; |
3927 | struct pid_namespace *ns; |
3928 | int tid; |
3929 | |
3930 | if (proc_inode_is_dead(inode)) |
3931 | return -ENOENT; |
3932 | |
3933 | if (!dir_emit_dots(file, ctx)) |
3934 | return 0; |
3935 | |
3936 | /* We cache the tgid value that the last readdir call couldn't |
3937 | * return and lseek resets it to 0. |
3938 | */ |
3939 | ns = proc_pid_ns(sb: inode->i_sb); |
3940 | tid = (int)(intptr_t)file->private_data; |
3941 | file->private_data = NULL; |
3942 | for (task = first_tid(pid: proc_pid(inode), tid, f_pos: ctx->pos - 2, ns); |
3943 | task; |
3944 | task = next_tid(start: task), ctx->pos++) { |
3945 | char name[10 + 1]; |
3946 | unsigned int len; |
3947 | |
3948 | tid = task_pid_nr_ns(tsk: task, ns); |
3949 | if (!tid) |
3950 | continue; /* The task has just exited. */ |
3951 | len = snprintf(buf: name, size: sizeof(name), fmt: "%u", tid); |
3952 | if (!proc_fill_cache(file, ctx, name, len, |
3953 | instantiate: proc_task_instantiate, task, NULL)) { |
3954 | /* returning this tgid failed, save it as the first |
3955 | * pid for the next readir call */ |
3956 | file->private_data = (void *)(intptr_t)tid; |
3957 | put_task_struct(t: task); |
3958 | break; |
3959 | } |
3960 | } |
3961 | |
3962 | return 0; |
3963 | } |
3964 | |
3965 | static int proc_task_getattr(struct mnt_idmap *idmap, |
3966 | const struct path *path, struct kstat *stat, |
3967 | u32 request_mask, unsigned int query_flags) |
3968 | { |
3969 | struct inode *inode = d_inode(dentry: path->dentry); |
3970 | struct task_struct *p = get_proc_task(inode); |
3971 | generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); |
3972 | |
3973 | if (p) { |
3974 | stat->nlink += get_nr_threads(task: p); |
3975 | put_task_struct(t: p); |
3976 | } |
3977 | |
3978 | return 0; |
3979 | } |
3980 | |
3981 | /* |
3982 | * proc_task_readdir() set @file->private_data to a positive integer |
3983 | * value, so casting that to u64 is safe. generic_llseek_cookie() will |
3984 | * set @cookie to 0, so casting to an int is safe. The WARN_ON_ONCE() is |
3985 | * here to catch any unexpected change in behavior either in |
3986 | * proc_task_readdir() or generic_llseek_cookie(). |
3987 | */ |
3988 | static loff_t proc_dir_llseek(struct file *file, loff_t offset, int whence) |
3989 | { |
3990 | u64 cookie = (u64)(intptr_t)file->private_data; |
3991 | loff_t off; |
3992 | |
3993 | off = generic_llseek_cookie(file, offset, whence, cookie: &cookie); |
3994 | WARN_ON_ONCE(cookie > INT_MAX); |
3995 | file->private_data = (void *)(intptr_t)cookie; /* serialized by f_pos_lock */ |
3996 | return off; |
3997 | } |
3998 | |
3999 | static const struct inode_operations proc_task_inode_operations = { |
4000 | .lookup = proc_task_lookup, |
4001 | .getattr = proc_task_getattr, |
4002 | .setattr = proc_setattr, |
4003 | .permission = proc_pid_permission, |
4004 | }; |
4005 | |
4006 | static const struct file_operations proc_task_operations = { |
4007 | .read = generic_read_dir, |
4008 | .iterate_shared = proc_task_readdir, |
4009 | .llseek = proc_dir_llseek, |
4010 | }; |
4011 | |
4012 | void __init set_proc_pid_nlink(void) |
4013 | { |
4014 | nlink_tid = pid_entry_nlink(entries: tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); |
4015 | nlink_tgid = pid_entry_nlink(entries: tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); |
4016 | } |
4017 |
Definitions
- nlink_tid
- nlink_tgid
- proc_mem_force
- proc_mem_force_override
- proc_mem_force_table
- early_proc_mem_force_override
- pid_entry
- pid_entry_nlink
- get_task_root
- proc_cwd_link
- proc_root_link
- get_mm_proctitle
- get_mm_cmdline
- get_task_cmdline
- proc_pid_cmdline_read
- proc_pid_cmdline_ops
- proc_pid_wchan
- lock_trace
- unlock_trace
- proc_pid_stack
- proc_pid_schedstat
- lstats_show_proc
- lstats_open
- lstats_write
- proc_lstats_operations
- proc_oom_score
- limit_names
- lnames
- proc_pid_limits
- proc_pid_syscall
- proc_fd_access_allowed
- proc_setattr
- has_pid_permissions
- proc_pid_permission
- proc_def_inode_operations
- proc_single_show
- proc_single_open
- proc_single_file_operations
- proc_mem_open
- __mem_open
- mem_open
- proc_mem_foll_force
- mem_rw
- mem_read
- mem_write
- mem_lseek
- mem_release
- proc_mem_operations
- environ_open
- environ_read
- proc_environ_operations
- auxv_open
- auxv_read
- proc_auxv_operations
- oom_adj_read
- __set_oom_adj
- oom_adj_write
- proc_oom_adj_operations
- oom_score_adj_read
- oom_score_adj_write
- proc_oom_score_adj_operations
- proc_loginuid_read
- proc_loginuid_write
- proc_loginuid_operations
- proc_sessionid_read
- proc_sessionid_operations
- proc_fault_inject_read
- proc_fault_inject_write
- proc_fault_inject_operations
- proc_fail_nth_write
- proc_fail_nth_read
- proc_fail_nth_operations
- sched_show
- sched_write
- sched_open
- proc_pid_sched_operations
- sched_autogroup_show
- sched_autogroup_write
- sched_autogroup_open
- proc_pid_sched_autogroup_operations
- timens_offsets_show
- timens_offsets_write
- timens_offsets_open
- proc_timens_offsets_operations
- comm_write
- comm_show
- comm_open
- proc_pid_set_comm_operations
- proc_exe_link
- proc_pid_get_link
- do_proc_readlink
- proc_pid_readlink
- proc_pid_link_inode_operations
- task_dump_owner
- proc_pid_evict_inode
- proc_pid_make_inode
- proc_pid_make_base_inode
- pid_getattr
- pid_update_inode
- pid_revalidate
- proc_inode_is_dead
- pid_delete_dentry
- pid_dentry_operations
- proc_fill_cache
- dname_to_vma_addr
- map_files_d_revalidate
- tid_map_files_dentry_operations
- map_files_get_link
- map_files_info
- proc_map_files_get_link
- proc_map_files_link_inode_operations
- proc_map_files_instantiate
- proc_map_files_lookup
- proc_map_files_inode_operations
- proc_map_files_readdir
- proc_map_files_operations
- timers_private
- timers_start
- timers_next
- timers_stop
- show_timer
- proc_timers_seq_ops
- proc_timers_open
- proc_timers_operations
- timerslack_ns_write
- timerslack_ns_show
- timerslack_ns_open
- proc_pid_set_timerslack_ns_operations
- proc_pident_instantiate
- proc_pident_lookup
- proc_pident_readdir
- proc_pid_attr_open
- proc_pid_attr_read
- proc_pid_attr_write
- proc_pid_attr_operations
- smack_attr_dir_stuff
- apparmor_attr_dir_stuff
- attr_dir_stuff
- proc_attr_dir_readdir
- proc_attr_dir_operations
- proc_attr_dir_lookup
- proc_attr_dir_inode_operations
- proc_coredump_filter_read
- proc_coredump_filter_write
- proc_coredump_filter_operations
- do_io_accounting
- proc_tid_io_accounting
- proc_tgid_io_accounting
- proc_id_map_open
- proc_id_map_release
- proc_uid_map_open
- proc_gid_map_open
- proc_projid_map_open
- proc_uid_map_operations
- proc_gid_map_operations
- proc_projid_map_operations
- proc_setgroups_open
- proc_setgroups_release
- proc_setgroups_operations
- proc_pid_personality
- proc_pid_ksm_merging_pages
- proc_pid_ksm_stat
- proc_task_operations
- proc_task_inode_operations
- tgid_base_stuff
- proc_tgid_base_readdir
- proc_tgid_base_operations
- tgid_pidfd_to_pid
- proc_tgid_base_lookup
- proc_tgid_base_inode_operations
- proc_flush_pid
- proc_pid_instantiate
- proc_pid_lookup
- tgid_iter
- next_tgid
- proc_pid_readdir
- proc_tid_comm_permission
- proc_tid_comm_inode_operations
- tid_base_stuff
- proc_tid_base_readdir
- proc_tid_base_lookup
- proc_tid_base_operations
- proc_tid_base_inode_operations
- proc_task_instantiate
- proc_task_lookup
- first_tid
- next_tid
- proc_task_readdir
- proc_task_getattr
- proc_dir_llseek
- proc_task_inode_operations
- proc_task_operations
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