1 /* 2 * linux/fs/proc/base.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * proc base directory handling functions 7 * 8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. 9 * Instead of using magical inumbers to determine the kind of object 10 * we allocate and fill in-core inodes upon lookup. They don't even 11 * go into icache. We cache the reference to task_struct upon lookup too. 12 * Eventually it should become a filesystem in its own. We don't use the 13 * rest of procfs anymore. 14 * 15 * 16 * Changelog: 17 * 17-Jan-2005 18 * Allan Bezerra 19 * Bruna Moreira <bruna.moreira@indt.org.br> 20 * Edjard Mota <edjard.mota@indt.org.br> 21 * Ilias Biris <ilias.biris@indt.org.br> 22 * Mauricio Lin <mauricio.lin@indt.org.br> 23 * 24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 25 * 26 * A new process specific entry (smaps) included in /proc. It shows the 27 * size of rss for each memory area. The maps entry lacks information 28 * about physical memory size (rss) for each mapped file, i.e., 29 * rss information for executables and library files. 30 * This additional information is useful for any tools that need to know 31 * about physical memory consumption for a process specific library. 32 * 33 * Changelog: 34 * 21-Feb-2005 35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 36 * Pud inclusion in the page table walking. 37 * 38 * ChangeLog: 39 * 10-Mar-2005 40 * 10LE Instituto Nokia de Tecnologia - INdT: 41 * A better way to walks through the page table as suggested by Hugh Dickins. 42 * 43 * Simo Piiroinen <simo.piiroinen@nokia.com>: 44 * Smaps information related to shared, private, clean and dirty pages. 45 * 46 * Paul Mundt <paul.mundt@nokia.com>: 47 * Overall revision about smaps. 48 */ 49 50 #include <asm/uaccess.h> 51 52 #include <linux/errno.h> 53 #include <linux/time.h> 54 #include <linux/proc_fs.h> 55 #include <linux/stat.h> 56 #include <linux/task_io_accounting_ops.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/fdtable.h> 61 #include <linux/string.h> 62 #include <linux/seq_file.h> 63 #include <linux/namei.h> 64 #include <linux/mnt_namespace.h> 65 #include <linux/mm.h> 66 #include <linux/swap.h> 67 #include <linux/rcupdate.h> 68 #include <linux/kallsyms.h> 69 #include <linux/stacktrace.h> 70 #include <linux/resource.h> 71 #include <linux/module.h> 72 #include <linux/mount.h> 73 #include <linux/security.h> 74 #include <linux/ptrace.h> 75 #include <linux/tracehook.h> 76 #include <linux/printk.h> 77 #include <linux/cgroup.h> 78 #include <linux/cpuset.h> 79 #include <linux/audit.h> 80 #include <linux/poll.h> 81 #include <linux/nsproxy.h> 82 #include <linux/oom.h> 83 #include <linux/elf.h> 84 #include <linux/pid_namespace.h> 85 #include <linux/user_namespace.h> 86 #include <linux/fs_struct.h> 87 #include <linux/slab.h> 88 #include <linux/flex_array.h> 89 #include <linux/posix-timers.h> 90 #ifdef CONFIG_HARDWALL 91 #include <asm/hardwall.h> 92 #endif 93 #include <trace/events/oom.h> 94 #include "internal.h" 95 #include "fd.h" 96 97 /* NOTE: 98 * Implementing inode permission operations in /proc is almost 99 * certainly an error. Permission checks need to happen during 100 * each system call not at open time. The reason is that most of 101 * what we wish to check for permissions in /proc varies at runtime. 102 * 103 * The classic example of a problem is opening file descriptors 104 * in /proc for a task before it execs a suid executable. 105 */ 106 107 struct pid_entry { 108 const char *name; 109 int len; 110 umode_t mode; 111 const struct inode_operations *iop; 112 const struct file_operations *fop; 113 union proc_op op; 114 }; 115 116 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 117 .name = (NAME), \ 118 .len = sizeof(NAME) - 1, \ 119 .mode = MODE, \ 120 .iop = IOP, \ 121 .fop = FOP, \ 122 .op = OP, \ 123 } 124 125 #define DIR(NAME, MODE, iops, fops) \ 126 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 127 #define LNK(NAME, get_link) \ 128 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 129 &proc_pid_link_inode_operations, NULL, \ 130 { .proc_get_link = get_link } ) 131 #define REG(NAME, MODE, fops) \ 132 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 133 #define ONE(NAME, MODE, show) \ 134 NOD(NAME, (S_IFREG|(MODE)), \ 135 NULL, &proc_single_file_operations, \ 136 { .proc_show = show } ) 137 138 /* 139 * Count the number of hardlinks for the pid_entry table, excluding the . 140 * and .. links. 141 */ 142 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, 143 unsigned int n) 144 { 145 unsigned int i; 146 unsigned int count; 147 148 count = 0; 149 for (i = 0; i < n; ++i) { 150 if (S_ISDIR(entries[i].mode)) 151 ++count; 152 } 153 154 return count; 155 } 156 157 static int get_task_root(struct task_struct *task, struct path *root) 158 { 159 int result = -ENOENT; 160 161 task_lock(task); 162 if (task->fs) { 163 get_fs_root(task->fs, root); 164 result = 0; 165 } 166 task_unlock(task); 167 return result; 168 } 169 170 static int proc_cwd_link(struct dentry *dentry, struct path *path) 171 { 172 struct task_struct *task = get_proc_task(dentry->d_inode); 173 int result = -ENOENT; 174 175 if (task) { 176 task_lock(task); 177 if (task->fs) { 178 get_fs_pwd(task->fs, path); 179 result = 0; 180 } 181 task_unlock(task); 182 put_task_struct(task); 183 } 184 return result; 185 } 186 187 static int proc_root_link(struct dentry *dentry, struct path *path) 188 { 189 struct task_struct *task = get_proc_task(dentry->d_inode); 190 int result = -ENOENT; 191 192 if (task) { 193 result = get_task_root(task, path); 194 put_task_struct(task); 195 } 196 return result; 197 } 198 199 static int proc_pid_cmdline(struct seq_file *m, struct pid_namespace *ns, 200 struct pid *pid, struct task_struct *task) 201 { 202 /* 203 * Rely on struct seq_operations::show() being called once 204 * per internal buffer allocation. See single_open(), traverse(). 205 */ 206 BUG_ON(m->size < PAGE_SIZE); 207 m->count += get_cmdline(task, m->buf, PAGE_SIZE); 208 return 0; 209 } 210 211 static int proc_pid_auxv(struct seq_file *m, struct pid_namespace *ns, 212 struct pid *pid, struct task_struct *task) 213 { 214 struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ); 215 if (mm && !IS_ERR(mm)) { 216 unsigned int nwords = 0; 217 do { 218 nwords += 2; 219 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 220 seq_write(m, mm->saved_auxv, nwords * sizeof(mm->saved_auxv[0])); 221 mmput(mm); 222 return 0; 223 } else 224 return PTR_ERR(mm); 225 } 226 227 228 #ifdef CONFIG_KALLSYMS 229 /* 230 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 231 * Returns the resolved symbol. If that fails, simply return the address. 232 */ 233 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 234 struct pid *pid, struct task_struct *task) 235 { 236 unsigned long wchan; 237 char symname[KSYM_NAME_LEN]; 238 239 wchan = get_wchan(task); 240 241 if (lookup_symbol_name(wchan, symname) < 0) 242 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 243 return 0; 244 else 245 return seq_printf(m, "%lu", wchan); 246 else 247 return seq_printf(m, "%s", symname); 248 } 249 #endif /* CONFIG_KALLSYMS */ 250 251 static int lock_trace(struct task_struct *task) 252 { 253 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 254 if (err) 255 return err; 256 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) { 257 mutex_unlock(&task->signal->cred_guard_mutex); 258 return -EPERM; 259 } 260 return 0; 261 } 262 263 static void unlock_trace(struct task_struct *task) 264 { 265 mutex_unlock(&task->signal->cred_guard_mutex); 266 } 267 268 #ifdef CONFIG_STACKTRACE 269 270 #define MAX_STACK_TRACE_DEPTH 64 271 272 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 273 struct pid *pid, struct task_struct *task) 274 { 275 struct stack_trace trace; 276 unsigned long *entries; 277 int err; 278 int i; 279 280 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 281 if (!entries) 282 return -ENOMEM; 283 284 trace.nr_entries = 0; 285 trace.max_entries = MAX_STACK_TRACE_DEPTH; 286 trace.entries = entries; 287 trace.skip = 0; 288 289 err = lock_trace(task); 290 if (!err) { 291 save_stack_trace_tsk(task, &trace); 292 293 for (i = 0; i < trace.nr_entries; i++) { 294 seq_printf(m, "[<%pK>] %pS\n", 295 (void *)entries[i], (void *)entries[i]); 296 } 297 unlock_trace(task); 298 } 299 kfree(entries); 300 301 return err; 302 } 303 #endif 304 305 #ifdef CONFIG_SCHEDSTATS 306 /* 307 * Provides /proc/PID/schedstat 308 */ 309 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 310 struct pid *pid, struct task_struct *task) 311 { 312 return seq_printf(m, "%llu %llu %lu\n", 313 (unsigned long long)task->se.sum_exec_runtime, 314 (unsigned long long)task->sched_info.run_delay, 315 task->sched_info.pcount); 316 } 317 #endif 318 319 #ifdef CONFIG_LATENCYTOP 320 static int lstats_show_proc(struct seq_file *m, void *v) 321 { 322 int i; 323 struct inode *inode = m->private; 324 struct task_struct *task = get_proc_task(inode); 325 326 if (!task) 327 return -ESRCH; 328 seq_puts(m, "Latency Top version : v0.1\n"); 329 for (i = 0; i < 32; i++) { 330 struct latency_record *lr = &task->latency_record[i]; 331 if (lr->backtrace[0]) { 332 int q; 333 seq_printf(m, "%i %li %li", 334 lr->count, lr->time, lr->max); 335 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 336 unsigned long bt = lr->backtrace[q]; 337 if (!bt) 338 break; 339 if (bt == ULONG_MAX) 340 break; 341 seq_printf(m, " %ps", (void *)bt); 342 } 343 seq_putc(m, '\n'); 344 } 345 346 } 347 put_task_struct(task); 348 return 0; 349 } 350 351 static int lstats_open(struct inode *inode, struct file *file) 352 { 353 return single_open(file, lstats_show_proc, inode); 354 } 355 356 static ssize_t lstats_write(struct file *file, const char __user *buf, 357 size_t count, loff_t *offs) 358 { 359 struct task_struct *task = get_proc_task(file_inode(file)); 360 361 if (!task) 362 return -ESRCH; 363 clear_all_latency_tracing(task); 364 put_task_struct(task); 365 366 return count; 367 } 368 369 static const struct file_operations proc_lstats_operations = { 370 .open = lstats_open, 371 .read = seq_read, 372 .write = lstats_write, 373 .llseek = seq_lseek, 374 .release = single_release, 375 }; 376 377 #endif 378 379 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 380 struct pid *pid, struct task_struct *task) 381 { 382 unsigned long totalpages = totalram_pages + total_swap_pages; 383 unsigned long points = 0; 384 385 read_lock(&tasklist_lock); 386 if (pid_alive(task)) 387 points = oom_badness(task, NULL, NULL, totalpages) * 388 1000 / totalpages; 389 read_unlock(&tasklist_lock); 390 return seq_printf(m, "%lu\n", points); 391 } 392 393 struct limit_names { 394 const char *name; 395 const char *unit; 396 }; 397 398 static const struct limit_names lnames[RLIM_NLIMITS] = { 399 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 400 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 401 [RLIMIT_DATA] = {"Max data size", "bytes"}, 402 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 403 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 404 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 405 [RLIMIT_NPROC] = {"Max processes", "processes"}, 406 [RLIMIT_NOFILE] = {"Max open files", "files"}, 407 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 408 [RLIMIT_AS] = {"Max address space", "bytes"}, 409 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 410 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 411 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 412 [RLIMIT_NICE] = {"Max nice priority", NULL}, 413 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 414 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 415 }; 416 417 /* Display limits for a process */ 418 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 419 struct pid *pid, struct task_struct *task) 420 { 421 unsigned int i; 422 unsigned long flags; 423 424 struct rlimit rlim[RLIM_NLIMITS]; 425 426 if (!lock_task_sighand(task, &flags)) 427 return 0; 428 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 429 unlock_task_sighand(task, &flags); 430 431 /* 432 * print the file header 433 */ 434 seq_printf(m, "%-25s %-20s %-20s %-10s\n", 435 "Limit", "Soft Limit", "Hard Limit", "Units"); 436 437 for (i = 0; i < RLIM_NLIMITS; i++) { 438 if (rlim[i].rlim_cur == RLIM_INFINITY) 439 seq_printf(m, "%-25s %-20s ", 440 lnames[i].name, "unlimited"); 441 else 442 seq_printf(m, "%-25s %-20lu ", 443 lnames[i].name, rlim[i].rlim_cur); 444 445 if (rlim[i].rlim_max == RLIM_INFINITY) 446 seq_printf(m, "%-20s ", "unlimited"); 447 else 448 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 449 450 if (lnames[i].unit) 451 seq_printf(m, "%-10s\n", lnames[i].unit); 452 else 453 seq_putc(m, '\n'); 454 } 455 456 return 0; 457 } 458 459 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 460 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 461 struct pid *pid, struct task_struct *task) 462 { 463 long nr; 464 unsigned long args[6], sp, pc; 465 int res = lock_trace(task); 466 if (res) 467 return res; 468 469 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 470 seq_puts(m, "running\n"); 471 else if (nr < 0) 472 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 473 else 474 seq_printf(m, 475 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 476 nr, 477 args[0], args[1], args[2], args[3], args[4], args[5], 478 sp, pc); 479 unlock_trace(task); 480 return res; 481 } 482 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 483 484 /************************************************************************/ 485 /* Here the fs part begins */ 486 /************************************************************************/ 487 488 /* permission checks */ 489 static int proc_fd_access_allowed(struct inode *inode) 490 { 491 struct task_struct *task; 492 int allowed = 0; 493 /* Allow access to a task's file descriptors if it is us or we 494 * may use ptrace attach to the process and find out that 495 * information. 496 */ 497 task = get_proc_task(inode); 498 if (task) { 499 allowed = ptrace_may_access(task, PTRACE_MODE_READ); 500 put_task_struct(task); 501 } 502 return allowed; 503 } 504 505 int proc_setattr(struct dentry *dentry, struct iattr *attr) 506 { 507 int error; 508 struct inode *inode = dentry->d_inode; 509 510 if (attr->ia_valid & ATTR_MODE) 511 return -EPERM; 512 513 error = inode_change_ok(inode, attr); 514 if (error) 515 return error; 516 517 setattr_copy(inode, attr); 518 mark_inode_dirty(inode); 519 return 0; 520 } 521 522 /* 523 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 524 * or euid/egid (for hide_pid_min=2)? 525 */ 526 static bool has_pid_permissions(struct pid_namespace *pid, 527 struct task_struct *task, 528 int hide_pid_min) 529 { 530 if (pid->hide_pid < hide_pid_min) 531 return true; 532 if (in_group_p(pid->pid_gid)) 533 return true; 534 return ptrace_may_access(task, PTRACE_MODE_READ); 535 } 536 537 538 static int proc_pid_permission(struct inode *inode, int mask) 539 { 540 struct pid_namespace *pid = inode->i_sb->s_fs_info; 541 struct task_struct *task; 542 bool has_perms; 543 544 task = get_proc_task(inode); 545 if (!task) 546 return -ESRCH; 547 has_perms = has_pid_permissions(pid, task, 1); 548 put_task_struct(task); 549 550 if (!has_perms) { 551 if (pid->hide_pid == 2) { 552 /* 553 * Let's make getdents(), stat(), and open() 554 * consistent with each other. If a process 555 * may not stat() a file, it shouldn't be seen 556 * in procfs at all. 557 */ 558 return -ENOENT; 559 } 560 561 return -EPERM; 562 } 563 return generic_permission(inode, mask); 564 } 565 566 567 568 static const struct inode_operations proc_def_inode_operations = { 569 .setattr = proc_setattr, 570 }; 571 572 static int proc_single_show(struct seq_file *m, void *v) 573 { 574 struct inode *inode = m->private; 575 struct pid_namespace *ns; 576 struct pid *pid; 577 struct task_struct *task; 578 int ret; 579 580 ns = inode->i_sb->s_fs_info; 581 pid = proc_pid(inode); 582 task = get_pid_task(pid, PIDTYPE_PID); 583 if (!task) 584 return -ESRCH; 585 586 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 587 588 put_task_struct(task); 589 return ret; 590 } 591 592 static int proc_single_open(struct inode *inode, struct file *filp) 593 { 594 return single_open(filp, proc_single_show, inode); 595 } 596 597 static const struct file_operations proc_single_file_operations = { 598 .open = proc_single_open, 599 .read = seq_read, 600 .llseek = seq_lseek, 601 .release = single_release, 602 }; 603 604 605 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 606 { 607 struct task_struct *task = get_proc_task(inode); 608 struct mm_struct *mm = ERR_PTR(-ESRCH); 609 610 if (task) { 611 mm = mm_access(task, mode); 612 put_task_struct(task); 613 614 if (!IS_ERR_OR_NULL(mm)) { 615 /* ensure this mm_struct can't be freed */ 616 atomic_inc(&mm->mm_count); 617 /* but do not pin its memory */ 618 mmput(mm); 619 } 620 } 621 622 return mm; 623 } 624 625 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 626 { 627 struct mm_struct *mm = proc_mem_open(inode, mode); 628 629 if (IS_ERR(mm)) 630 return PTR_ERR(mm); 631 632 file->private_data = mm; 633 return 0; 634 } 635 636 static int mem_open(struct inode *inode, struct file *file) 637 { 638 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 639 640 /* OK to pass negative loff_t, we can catch out-of-range */ 641 file->f_mode |= FMODE_UNSIGNED_OFFSET; 642 643 return ret; 644 } 645 646 static ssize_t mem_rw(struct file *file, char __user *buf, 647 size_t count, loff_t *ppos, int write) 648 { 649 struct mm_struct *mm = file->private_data; 650 unsigned long addr = *ppos; 651 ssize_t copied; 652 char *page; 653 654 if (!mm) 655 return 0; 656 657 page = (char *)__get_free_page(GFP_TEMPORARY); 658 if (!page) 659 return -ENOMEM; 660 661 copied = 0; 662 if (!atomic_inc_not_zero(&mm->mm_users)) 663 goto free; 664 665 while (count > 0) { 666 int this_len = min_t(int, count, PAGE_SIZE); 667 668 if (write && copy_from_user(page, buf, this_len)) { 669 copied = -EFAULT; 670 break; 671 } 672 673 this_len = access_remote_vm(mm, addr, page, this_len, write); 674 if (!this_len) { 675 if (!copied) 676 copied = -EIO; 677 break; 678 } 679 680 if (!write && copy_to_user(buf, page, this_len)) { 681 copied = -EFAULT; 682 break; 683 } 684 685 buf += this_len; 686 addr += this_len; 687 copied += this_len; 688 count -= this_len; 689 } 690 *ppos = addr; 691 692 mmput(mm); 693 free: 694 free_page((unsigned long) page); 695 return copied; 696 } 697 698 static ssize_t mem_read(struct file *file, char __user *buf, 699 size_t count, loff_t *ppos) 700 { 701 return mem_rw(file, buf, count, ppos, 0); 702 } 703 704 static ssize_t mem_write(struct file *file, const char __user *buf, 705 size_t count, loff_t *ppos) 706 { 707 return mem_rw(file, (char __user*)buf, count, ppos, 1); 708 } 709 710 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 711 { 712 switch (orig) { 713 case 0: 714 file->f_pos = offset; 715 break; 716 case 1: 717 file->f_pos += offset; 718 break; 719 default: 720 return -EINVAL; 721 } 722 force_successful_syscall_return(); 723 return file->f_pos; 724 } 725 726 static int mem_release(struct inode *inode, struct file *file) 727 { 728 struct mm_struct *mm = file->private_data; 729 if (mm) 730 mmdrop(mm); 731 return 0; 732 } 733 734 static const struct file_operations proc_mem_operations = { 735 .llseek = mem_lseek, 736 .read = mem_read, 737 .write = mem_write, 738 .open = mem_open, 739 .release = mem_release, 740 }; 741 742 static int environ_open(struct inode *inode, struct file *file) 743 { 744 return __mem_open(inode, file, PTRACE_MODE_READ); 745 } 746 747 static ssize_t environ_read(struct file *file, char __user *buf, 748 size_t count, loff_t *ppos) 749 { 750 char *page; 751 unsigned long src = *ppos; 752 int ret = 0; 753 struct mm_struct *mm = file->private_data; 754 755 if (!mm) 756 return 0; 757 758 page = (char *)__get_free_page(GFP_TEMPORARY); 759 if (!page) 760 return -ENOMEM; 761 762 ret = 0; 763 if (!atomic_inc_not_zero(&mm->mm_users)) 764 goto free; 765 while (count > 0) { 766 size_t this_len, max_len; 767 int retval; 768 769 if (src >= (mm->env_end - mm->env_start)) 770 break; 771 772 this_len = mm->env_end - (mm->env_start + src); 773 774 max_len = min_t(size_t, PAGE_SIZE, count); 775 this_len = min(max_len, this_len); 776 777 retval = access_remote_vm(mm, (mm->env_start + src), 778 page, this_len, 0); 779 780 if (retval <= 0) { 781 ret = retval; 782 break; 783 } 784 785 if (copy_to_user(buf, page, retval)) { 786 ret = -EFAULT; 787 break; 788 } 789 790 ret += retval; 791 src += retval; 792 buf += retval; 793 count -= retval; 794 } 795 *ppos = src; 796 mmput(mm); 797 798 free: 799 free_page((unsigned long) page); 800 return ret; 801 } 802 803 static const struct file_operations proc_environ_operations = { 804 .open = environ_open, 805 .read = environ_read, 806 .llseek = generic_file_llseek, 807 .release = mem_release, 808 }; 809 810 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 811 loff_t *ppos) 812 { 813 struct task_struct *task = get_proc_task(file_inode(file)); 814 char buffer[PROC_NUMBUF]; 815 int oom_adj = OOM_ADJUST_MIN; 816 size_t len; 817 unsigned long flags; 818 819 if (!task) 820 return -ESRCH; 821 if (lock_task_sighand(task, &flags)) { 822 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 823 oom_adj = OOM_ADJUST_MAX; 824 else 825 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 826 OOM_SCORE_ADJ_MAX; 827 unlock_task_sighand(task, &flags); 828 } 829 put_task_struct(task); 830 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 831 return simple_read_from_buffer(buf, count, ppos, buffer, len); 832 } 833 834 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 835 size_t count, loff_t *ppos) 836 { 837 struct task_struct *task; 838 char buffer[PROC_NUMBUF]; 839 int oom_adj; 840 unsigned long flags; 841 int err; 842 843 memset(buffer, 0, sizeof(buffer)); 844 if (count > sizeof(buffer) - 1) 845 count = sizeof(buffer) - 1; 846 if (copy_from_user(buffer, buf, count)) { 847 err = -EFAULT; 848 goto out; 849 } 850 851 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 852 if (err) 853 goto out; 854 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 855 oom_adj != OOM_DISABLE) { 856 err = -EINVAL; 857 goto out; 858 } 859 860 task = get_proc_task(file_inode(file)); 861 if (!task) { 862 err = -ESRCH; 863 goto out; 864 } 865 866 task_lock(task); 867 if (!task->mm) { 868 err = -EINVAL; 869 goto err_task_lock; 870 } 871 872 if (!lock_task_sighand(task, &flags)) { 873 err = -ESRCH; 874 goto err_task_lock; 875 } 876 877 /* 878 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 879 * value is always attainable. 880 */ 881 if (oom_adj == OOM_ADJUST_MAX) 882 oom_adj = OOM_SCORE_ADJ_MAX; 883 else 884 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 885 886 if (oom_adj < task->signal->oom_score_adj && 887 !capable(CAP_SYS_RESOURCE)) { 888 err = -EACCES; 889 goto err_sighand; 890 } 891 892 /* 893 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 894 * /proc/pid/oom_score_adj instead. 895 */ 896 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 897 current->comm, task_pid_nr(current), task_pid_nr(task), 898 task_pid_nr(task)); 899 900 task->signal->oom_score_adj = oom_adj; 901 trace_oom_score_adj_update(task); 902 err_sighand: 903 unlock_task_sighand(task, &flags); 904 err_task_lock: 905 task_unlock(task); 906 put_task_struct(task); 907 out: 908 return err < 0 ? err : count; 909 } 910 911 static const struct file_operations proc_oom_adj_operations = { 912 .read = oom_adj_read, 913 .write = oom_adj_write, 914 .llseek = generic_file_llseek, 915 }; 916 917 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 918 size_t count, loff_t *ppos) 919 { 920 struct task_struct *task = get_proc_task(file_inode(file)); 921 char buffer[PROC_NUMBUF]; 922 short oom_score_adj = OOM_SCORE_ADJ_MIN; 923 unsigned long flags; 924 size_t len; 925 926 if (!task) 927 return -ESRCH; 928 if (lock_task_sighand(task, &flags)) { 929 oom_score_adj = task->signal->oom_score_adj; 930 unlock_task_sighand(task, &flags); 931 } 932 put_task_struct(task); 933 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 934 return simple_read_from_buffer(buf, count, ppos, buffer, len); 935 } 936 937 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 938 size_t count, loff_t *ppos) 939 { 940 struct task_struct *task; 941 char buffer[PROC_NUMBUF]; 942 unsigned long flags; 943 int oom_score_adj; 944 int err; 945 946 memset(buffer, 0, sizeof(buffer)); 947 if (count > sizeof(buffer) - 1) 948 count = sizeof(buffer) - 1; 949 if (copy_from_user(buffer, buf, count)) { 950 err = -EFAULT; 951 goto out; 952 } 953 954 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 955 if (err) 956 goto out; 957 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 958 oom_score_adj > OOM_SCORE_ADJ_MAX) { 959 err = -EINVAL; 960 goto out; 961 } 962 963 task = get_proc_task(file_inode(file)); 964 if (!task) { 965 err = -ESRCH; 966 goto out; 967 } 968 969 task_lock(task); 970 if (!task->mm) { 971 err = -EINVAL; 972 goto err_task_lock; 973 } 974 975 if (!lock_task_sighand(task, &flags)) { 976 err = -ESRCH; 977 goto err_task_lock; 978 } 979 980 if ((short)oom_score_adj < task->signal->oom_score_adj_min && 981 !capable(CAP_SYS_RESOURCE)) { 982 err = -EACCES; 983 goto err_sighand; 984 } 985 986 task->signal->oom_score_adj = (short)oom_score_adj; 987 if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) 988 task->signal->oom_score_adj_min = (short)oom_score_adj; 989 trace_oom_score_adj_update(task); 990 991 err_sighand: 992 unlock_task_sighand(task, &flags); 993 err_task_lock: 994 task_unlock(task); 995 put_task_struct(task); 996 out: 997 return err < 0 ? err : count; 998 } 999 1000 static const struct file_operations proc_oom_score_adj_operations = { 1001 .read = oom_score_adj_read, 1002 .write = oom_score_adj_write, 1003 .llseek = default_llseek, 1004 }; 1005 1006 #ifdef CONFIG_AUDITSYSCALL 1007 #define TMPBUFLEN 21 1008 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1009 size_t count, loff_t *ppos) 1010 { 1011 struct inode * inode = file_inode(file); 1012 struct task_struct *task = get_proc_task(inode); 1013 ssize_t length; 1014 char tmpbuf[TMPBUFLEN]; 1015 1016 if (!task) 1017 return -ESRCH; 1018 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1019 from_kuid(file->f_cred->user_ns, 1020 audit_get_loginuid(task))); 1021 put_task_struct(task); 1022 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1023 } 1024 1025 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1026 size_t count, loff_t *ppos) 1027 { 1028 struct inode * inode = file_inode(file); 1029 char *page, *tmp; 1030 ssize_t length; 1031 uid_t loginuid; 1032 kuid_t kloginuid; 1033 1034 rcu_read_lock(); 1035 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1036 rcu_read_unlock(); 1037 return -EPERM; 1038 } 1039 rcu_read_unlock(); 1040 1041 if (count >= PAGE_SIZE) 1042 count = PAGE_SIZE - 1; 1043 1044 if (*ppos != 0) { 1045 /* No partial writes. */ 1046 return -EINVAL; 1047 } 1048 page = (char*)__get_free_page(GFP_TEMPORARY); 1049 if (!page) 1050 return -ENOMEM; 1051 length = -EFAULT; 1052 if (copy_from_user(page, buf, count)) 1053 goto out_free_page; 1054 1055 page[count] = '\0'; 1056 loginuid = simple_strtoul(page, &tmp, 10); 1057 if (tmp == page) { 1058 length = -EINVAL; 1059 goto out_free_page; 1060 1061 } 1062 1063 /* is userspace tring to explicitly UNSET the loginuid? */ 1064 if (loginuid == AUDIT_UID_UNSET) { 1065 kloginuid = INVALID_UID; 1066 } else { 1067 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1068 if (!uid_valid(kloginuid)) { 1069 length = -EINVAL; 1070 goto out_free_page; 1071 } 1072 } 1073 1074 length = audit_set_loginuid(kloginuid); 1075 if (likely(length == 0)) 1076 length = count; 1077 1078 out_free_page: 1079 free_page((unsigned long) page); 1080 return length; 1081 } 1082 1083 static const struct file_operations proc_loginuid_operations = { 1084 .read = proc_loginuid_read, 1085 .write = proc_loginuid_write, 1086 .llseek = generic_file_llseek, 1087 }; 1088 1089 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1090 size_t count, loff_t *ppos) 1091 { 1092 struct inode * inode = file_inode(file); 1093 struct task_struct *task = get_proc_task(inode); 1094 ssize_t length; 1095 char tmpbuf[TMPBUFLEN]; 1096 1097 if (!task) 1098 return -ESRCH; 1099 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1100 audit_get_sessionid(task)); 1101 put_task_struct(task); 1102 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1103 } 1104 1105 static const struct file_operations proc_sessionid_operations = { 1106 .read = proc_sessionid_read, 1107 .llseek = generic_file_llseek, 1108 }; 1109 #endif 1110 1111 #ifdef CONFIG_FAULT_INJECTION 1112 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1113 size_t count, loff_t *ppos) 1114 { 1115 struct task_struct *task = get_proc_task(file_inode(file)); 1116 char buffer[PROC_NUMBUF]; 1117 size_t len; 1118 int make_it_fail; 1119 1120 if (!task) 1121 return -ESRCH; 1122 make_it_fail = task->make_it_fail; 1123 put_task_struct(task); 1124 1125 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1126 1127 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1128 } 1129 1130 static ssize_t proc_fault_inject_write(struct file * file, 1131 const char __user * buf, size_t count, loff_t *ppos) 1132 { 1133 struct task_struct *task; 1134 char buffer[PROC_NUMBUF], *end; 1135 int make_it_fail; 1136 1137 if (!capable(CAP_SYS_RESOURCE)) 1138 return -EPERM; 1139 memset(buffer, 0, sizeof(buffer)); 1140 if (count > sizeof(buffer) - 1) 1141 count = sizeof(buffer) - 1; 1142 if (copy_from_user(buffer, buf, count)) 1143 return -EFAULT; 1144 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1145 if (*end) 1146 return -EINVAL; 1147 if (make_it_fail < 0 || make_it_fail > 1) 1148 return -EINVAL; 1149 1150 task = get_proc_task(file_inode(file)); 1151 if (!task) 1152 return -ESRCH; 1153 task->make_it_fail = make_it_fail; 1154 put_task_struct(task); 1155 1156 return count; 1157 } 1158 1159 static const struct file_operations proc_fault_inject_operations = { 1160 .read = proc_fault_inject_read, 1161 .write = proc_fault_inject_write, 1162 .llseek = generic_file_llseek, 1163 }; 1164 #endif 1165 1166 1167 #ifdef CONFIG_SCHED_DEBUG 1168 /* 1169 * Print out various scheduling related per-task fields: 1170 */ 1171 static int sched_show(struct seq_file *m, void *v) 1172 { 1173 struct inode *inode = m->private; 1174 struct task_struct *p; 1175 1176 p = get_proc_task(inode); 1177 if (!p) 1178 return -ESRCH; 1179 proc_sched_show_task(p, m); 1180 1181 put_task_struct(p); 1182 1183 return 0; 1184 } 1185 1186 static ssize_t 1187 sched_write(struct file *file, const char __user *buf, 1188 size_t count, loff_t *offset) 1189 { 1190 struct inode *inode = file_inode(file); 1191 struct task_struct *p; 1192 1193 p = get_proc_task(inode); 1194 if (!p) 1195 return -ESRCH; 1196 proc_sched_set_task(p); 1197 1198 put_task_struct(p); 1199 1200 return count; 1201 } 1202 1203 static int sched_open(struct inode *inode, struct file *filp) 1204 { 1205 return single_open(filp, sched_show, inode); 1206 } 1207 1208 static const struct file_operations proc_pid_sched_operations = { 1209 .open = sched_open, 1210 .read = seq_read, 1211 .write = sched_write, 1212 .llseek = seq_lseek, 1213 .release = single_release, 1214 }; 1215 1216 #endif 1217 1218 #ifdef CONFIG_SCHED_AUTOGROUP 1219 /* 1220 * Print out autogroup related information: 1221 */ 1222 static int sched_autogroup_show(struct seq_file *m, void *v) 1223 { 1224 struct inode *inode = m->private; 1225 struct task_struct *p; 1226 1227 p = get_proc_task(inode); 1228 if (!p) 1229 return -ESRCH; 1230 proc_sched_autogroup_show_task(p, m); 1231 1232 put_task_struct(p); 1233 1234 return 0; 1235 } 1236 1237 static ssize_t 1238 sched_autogroup_write(struct file *file, const char __user *buf, 1239 size_t count, loff_t *offset) 1240 { 1241 struct inode *inode = file_inode(file); 1242 struct task_struct *p; 1243 char buffer[PROC_NUMBUF]; 1244 int nice; 1245 int err; 1246 1247 memset(buffer, 0, sizeof(buffer)); 1248 if (count > sizeof(buffer) - 1) 1249 count = sizeof(buffer) - 1; 1250 if (copy_from_user(buffer, buf, count)) 1251 return -EFAULT; 1252 1253 err = kstrtoint(strstrip(buffer), 0, &nice); 1254 if (err < 0) 1255 return err; 1256 1257 p = get_proc_task(inode); 1258 if (!p) 1259 return -ESRCH; 1260 1261 err = proc_sched_autogroup_set_nice(p, nice); 1262 if (err) 1263 count = err; 1264 1265 put_task_struct(p); 1266 1267 return count; 1268 } 1269 1270 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1271 { 1272 int ret; 1273 1274 ret = single_open(filp, sched_autogroup_show, NULL); 1275 if (!ret) { 1276 struct seq_file *m = filp->private_data; 1277 1278 m->private = inode; 1279 } 1280 return ret; 1281 } 1282 1283 static const struct file_operations proc_pid_sched_autogroup_operations = { 1284 .open = sched_autogroup_open, 1285 .read = seq_read, 1286 .write = sched_autogroup_write, 1287 .llseek = seq_lseek, 1288 .release = single_release, 1289 }; 1290 1291 #endif /* CONFIG_SCHED_AUTOGROUP */ 1292 1293 static ssize_t comm_write(struct file *file, const char __user *buf, 1294 size_t count, loff_t *offset) 1295 { 1296 struct inode *inode = file_inode(file); 1297 struct task_struct *p; 1298 char buffer[TASK_COMM_LEN]; 1299 const size_t maxlen = sizeof(buffer) - 1; 1300 1301 memset(buffer, 0, sizeof(buffer)); 1302 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1303 return -EFAULT; 1304 1305 p = get_proc_task(inode); 1306 if (!p) 1307 return -ESRCH; 1308 1309 if (same_thread_group(current, p)) 1310 set_task_comm(p, buffer); 1311 else 1312 count = -EINVAL; 1313 1314 put_task_struct(p); 1315 1316 return count; 1317 } 1318 1319 static int comm_show(struct seq_file *m, void *v) 1320 { 1321 struct inode *inode = m->private; 1322 struct task_struct *p; 1323 1324 p = get_proc_task(inode); 1325 if (!p) 1326 return -ESRCH; 1327 1328 task_lock(p); 1329 seq_printf(m, "%s\n", p->comm); 1330 task_unlock(p); 1331 1332 put_task_struct(p); 1333 1334 return 0; 1335 } 1336 1337 static int comm_open(struct inode *inode, struct file *filp) 1338 { 1339 return single_open(filp, comm_show, inode); 1340 } 1341 1342 static const struct file_operations proc_pid_set_comm_operations = { 1343 .open = comm_open, 1344 .read = seq_read, 1345 .write = comm_write, 1346 .llseek = seq_lseek, 1347 .release = single_release, 1348 }; 1349 1350 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1351 { 1352 struct task_struct *task; 1353 struct mm_struct *mm; 1354 struct file *exe_file; 1355 1356 task = get_proc_task(dentry->d_inode); 1357 if (!task) 1358 return -ENOENT; 1359 mm = get_task_mm(task); 1360 put_task_struct(task); 1361 if (!mm) 1362 return -ENOENT; 1363 exe_file = get_mm_exe_file(mm); 1364 mmput(mm); 1365 if (exe_file) { 1366 *exe_path = exe_file->f_path; 1367 path_get(&exe_file->f_path); 1368 fput(exe_file); 1369 return 0; 1370 } else 1371 return -ENOENT; 1372 } 1373 1374 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1375 { 1376 struct inode *inode = dentry->d_inode; 1377 struct path path; 1378 int error = -EACCES; 1379 1380 /* Are we allowed to snoop on the tasks file descriptors? */ 1381 if (!proc_fd_access_allowed(inode)) 1382 goto out; 1383 1384 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1385 if (error) 1386 goto out; 1387 1388 nd_jump_link(nd, &path); 1389 return NULL; 1390 out: 1391 return ERR_PTR(error); 1392 } 1393 1394 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1395 { 1396 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1397 char *pathname; 1398 int len; 1399 1400 if (!tmp) 1401 return -ENOMEM; 1402 1403 pathname = d_path(path, tmp, PAGE_SIZE); 1404 len = PTR_ERR(pathname); 1405 if (IS_ERR(pathname)) 1406 goto out; 1407 len = tmp + PAGE_SIZE - 1 - pathname; 1408 1409 if (len > buflen) 1410 len = buflen; 1411 if (copy_to_user(buffer, pathname, len)) 1412 len = -EFAULT; 1413 out: 1414 free_page((unsigned long)tmp); 1415 return len; 1416 } 1417 1418 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1419 { 1420 int error = -EACCES; 1421 struct inode *inode = dentry->d_inode; 1422 struct path path; 1423 1424 /* Are we allowed to snoop on the tasks file descriptors? */ 1425 if (!proc_fd_access_allowed(inode)) 1426 goto out; 1427 1428 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1429 if (error) 1430 goto out; 1431 1432 error = do_proc_readlink(&path, buffer, buflen); 1433 path_put(&path); 1434 out: 1435 return error; 1436 } 1437 1438 const struct inode_operations proc_pid_link_inode_operations = { 1439 .readlink = proc_pid_readlink, 1440 .follow_link = proc_pid_follow_link, 1441 .setattr = proc_setattr, 1442 }; 1443 1444 1445 /* building an inode */ 1446 1447 struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1448 { 1449 struct inode * inode; 1450 struct proc_inode *ei; 1451 const struct cred *cred; 1452 1453 /* We need a new inode */ 1454 1455 inode = new_inode(sb); 1456 if (!inode) 1457 goto out; 1458 1459 /* Common stuff */ 1460 ei = PROC_I(inode); 1461 inode->i_ino = get_next_ino(); 1462 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1463 inode->i_op = &proc_def_inode_operations; 1464 1465 /* 1466 * grab the reference to task. 1467 */ 1468 ei->pid = get_task_pid(task, PIDTYPE_PID); 1469 if (!ei->pid) 1470 goto out_unlock; 1471 1472 if (task_dumpable(task)) { 1473 rcu_read_lock(); 1474 cred = __task_cred(task); 1475 inode->i_uid = cred->euid; 1476 inode->i_gid = cred->egid; 1477 rcu_read_unlock(); 1478 } 1479 security_task_to_inode(task, inode); 1480 1481 out: 1482 return inode; 1483 1484 out_unlock: 1485 iput(inode); 1486 return NULL; 1487 } 1488 1489 int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1490 { 1491 struct inode *inode = dentry->d_inode; 1492 struct task_struct *task; 1493 const struct cred *cred; 1494 struct pid_namespace *pid = dentry->d_sb->s_fs_info; 1495 1496 generic_fillattr(inode, stat); 1497 1498 rcu_read_lock(); 1499 stat->uid = GLOBAL_ROOT_UID; 1500 stat->gid = GLOBAL_ROOT_GID; 1501 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1502 if (task) { 1503 if (!has_pid_permissions(pid, task, 2)) { 1504 rcu_read_unlock(); 1505 /* 1506 * This doesn't prevent learning whether PID exists, 1507 * it only makes getattr() consistent with readdir(). 1508 */ 1509 return -ENOENT; 1510 } 1511 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1512 task_dumpable(task)) { 1513 cred = __task_cred(task); 1514 stat->uid = cred->euid; 1515 stat->gid = cred->egid; 1516 } 1517 } 1518 rcu_read_unlock(); 1519 return 0; 1520 } 1521 1522 /* dentry stuff */ 1523 1524 /* 1525 * Exceptional case: normally we are not allowed to unhash a busy 1526 * directory. In this case, however, we can do it - no aliasing problems 1527 * due to the way we treat inodes. 1528 * 1529 * Rewrite the inode's ownerships here because the owning task may have 1530 * performed a setuid(), etc. 1531 * 1532 * Before the /proc/pid/status file was created the only way to read 1533 * the effective uid of a /process was to stat /proc/pid. Reading 1534 * /proc/pid/status is slow enough that procps and other packages 1535 * kept stating /proc/pid. To keep the rules in /proc simple I have 1536 * made this apply to all per process world readable and executable 1537 * directories. 1538 */ 1539 int pid_revalidate(struct dentry *dentry, unsigned int flags) 1540 { 1541 struct inode *inode; 1542 struct task_struct *task; 1543 const struct cred *cred; 1544 1545 if (flags & LOOKUP_RCU) 1546 return -ECHILD; 1547 1548 inode = dentry->d_inode; 1549 task = get_proc_task(inode); 1550 1551 if (task) { 1552 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1553 task_dumpable(task)) { 1554 rcu_read_lock(); 1555 cred = __task_cred(task); 1556 inode->i_uid = cred->euid; 1557 inode->i_gid = cred->egid; 1558 rcu_read_unlock(); 1559 } else { 1560 inode->i_uid = GLOBAL_ROOT_UID; 1561 inode->i_gid = GLOBAL_ROOT_GID; 1562 } 1563 inode->i_mode &= ~(S_ISUID | S_ISGID); 1564 security_task_to_inode(task, inode); 1565 put_task_struct(task); 1566 return 1; 1567 } 1568 return 0; 1569 } 1570 1571 static inline bool proc_inode_is_dead(struct inode *inode) 1572 { 1573 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1574 } 1575 1576 int pid_delete_dentry(const struct dentry *dentry) 1577 { 1578 /* Is the task we represent dead? 1579 * If so, then don't put the dentry on the lru list, 1580 * kill it immediately. 1581 */ 1582 return proc_inode_is_dead(dentry->d_inode); 1583 } 1584 1585 const struct dentry_operations pid_dentry_operations = 1586 { 1587 .d_revalidate = pid_revalidate, 1588 .d_delete = pid_delete_dentry, 1589 }; 1590 1591 /* Lookups */ 1592 1593 /* 1594 * Fill a directory entry. 1595 * 1596 * If possible create the dcache entry and derive our inode number and 1597 * file type from dcache entry. 1598 * 1599 * Since all of the proc inode numbers are dynamically generated, the inode 1600 * numbers do not exist until the inode is cache. This means creating the 1601 * the dcache entry in readdir is necessary to keep the inode numbers 1602 * reported by readdir in sync with the inode numbers reported 1603 * by stat. 1604 */ 1605 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1606 const char *name, int len, 1607 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1608 { 1609 struct dentry *child, *dir = file->f_path.dentry; 1610 struct qstr qname = QSTR_INIT(name, len); 1611 struct inode *inode; 1612 unsigned type; 1613 ino_t ino; 1614 1615 child = d_hash_and_lookup(dir, &qname); 1616 if (!child) { 1617 child = d_alloc(dir, &qname); 1618 if (!child) 1619 goto end_instantiate; 1620 if (instantiate(dir->d_inode, child, task, ptr) < 0) { 1621 dput(child); 1622 goto end_instantiate; 1623 } 1624 } 1625 inode = child->d_inode; 1626 ino = inode->i_ino; 1627 type = inode->i_mode >> 12; 1628 dput(child); 1629 return dir_emit(ctx, name, len, ino, type); 1630 1631 end_instantiate: 1632 return dir_emit(ctx, name, len, 1, DT_UNKNOWN); 1633 } 1634 1635 #ifdef CONFIG_CHECKPOINT_RESTORE 1636 1637 /* 1638 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1639 * which represent vma start and end addresses. 1640 */ 1641 static int dname_to_vma_addr(struct dentry *dentry, 1642 unsigned long *start, unsigned long *end) 1643 { 1644 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) 1645 return -EINVAL; 1646 1647 return 0; 1648 } 1649 1650 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1651 { 1652 unsigned long vm_start, vm_end; 1653 bool exact_vma_exists = false; 1654 struct mm_struct *mm = NULL; 1655 struct task_struct *task; 1656 const struct cred *cred; 1657 struct inode *inode; 1658 int status = 0; 1659 1660 if (flags & LOOKUP_RCU) 1661 return -ECHILD; 1662 1663 if (!capable(CAP_SYS_ADMIN)) { 1664 status = -EPERM; 1665 goto out_notask; 1666 } 1667 1668 inode = dentry->d_inode; 1669 task = get_proc_task(inode); 1670 if (!task) 1671 goto out_notask; 1672 1673 mm = mm_access(task, PTRACE_MODE_READ); 1674 if (IS_ERR_OR_NULL(mm)) 1675 goto out; 1676 1677 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1678 down_read(&mm->mmap_sem); 1679 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1680 up_read(&mm->mmap_sem); 1681 } 1682 1683 mmput(mm); 1684 1685 if (exact_vma_exists) { 1686 if (task_dumpable(task)) { 1687 rcu_read_lock(); 1688 cred = __task_cred(task); 1689 inode->i_uid = cred->euid; 1690 inode->i_gid = cred->egid; 1691 rcu_read_unlock(); 1692 } else { 1693 inode->i_uid = GLOBAL_ROOT_UID; 1694 inode->i_gid = GLOBAL_ROOT_GID; 1695 } 1696 security_task_to_inode(task, inode); 1697 status = 1; 1698 } 1699 1700 out: 1701 put_task_struct(task); 1702 1703 out_notask: 1704 return status; 1705 } 1706 1707 static const struct dentry_operations tid_map_files_dentry_operations = { 1708 .d_revalidate = map_files_d_revalidate, 1709 .d_delete = pid_delete_dentry, 1710 }; 1711 1712 static int proc_map_files_get_link(struct dentry *dentry, struct path *path) 1713 { 1714 unsigned long vm_start, vm_end; 1715 struct vm_area_struct *vma; 1716 struct task_struct *task; 1717 struct mm_struct *mm; 1718 int rc; 1719 1720 rc = -ENOENT; 1721 task = get_proc_task(dentry->d_inode); 1722 if (!task) 1723 goto out; 1724 1725 mm = get_task_mm(task); 1726 put_task_struct(task); 1727 if (!mm) 1728 goto out; 1729 1730 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1731 if (rc) 1732 goto out_mmput; 1733 1734 rc = -ENOENT; 1735 down_read(&mm->mmap_sem); 1736 vma = find_exact_vma(mm, vm_start, vm_end); 1737 if (vma && vma->vm_file) { 1738 *path = vma->vm_file->f_path; 1739 path_get(path); 1740 rc = 0; 1741 } 1742 up_read(&mm->mmap_sem); 1743 1744 out_mmput: 1745 mmput(mm); 1746 out: 1747 return rc; 1748 } 1749 1750 struct map_files_info { 1751 fmode_t mode; 1752 unsigned long len; 1753 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ 1754 }; 1755 1756 static int 1757 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, 1758 struct task_struct *task, const void *ptr) 1759 { 1760 fmode_t mode = (fmode_t)(unsigned long)ptr; 1761 struct proc_inode *ei; 1762 struct inode *inode; 1763 1764 inode = proc_pid_make_inode(dir->i_sb, task); 1765 if (!inode) 1766 return -ENOENT; 1767 1768 ei = PROC_I(inode); 1769 ei->op.proc_get_link = proc_map_files_get_link; 1770 1771 inode->i_op = &proc_pid_link_inode_operations; 1772 inode->i_size = 64; 1773 inode->i_mode = S_IFLNK; 1774 1775 if (mode & FMODE_READ) 1776 inode->i_mode |= S_IRUSR; 1777 if (mode & FMODE_WRITE) 1778 inode->i_mode |= S_IWUSR; 1779 1780 d_set_d_op(dentry, &tid_map_files_dentry_operations); 1781 d_add(dentry, inode); 1782 1783 return 0; 1784 } 1785 1786 static struct dentry *proc_map_files_lookup(struct inode *dir, 1787 struct dentry *dentry, unsigned int flags) 1788 { 1789 unsigned long vm_start, vm_end; 1790 struct vm_area_struct *vma; 1791 struct task_struct *task; 1792 int result; 1793 struct mm_struct *mm; 1794 1795 result = -EPERM; 1796 if (!capable(CAP_SYS_ADMIN)) 1797 goto out; 1798 1799 result = -ENOENT; 1800 task = get_proc_task(dir); 1801 if (!task) 1802 goto out; 1803 1804 result = -EACCES; 1805 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 1806 goto out_put_task; 1807 1808 result = -ENOENT; 1809 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 1810 goto out_put_task; 1811 1812 mm = get_task_mm(task); 1813 if (!mm) 1814 goto out_put_task; 1815 1816 down_read(&mm->mmap_sem); 1817 vma = find_exact_vma(mm, vm_start, vm_end); 1818 if (!vma) 1819 goto out_no_vma; 1820 1821 if (vma->vm_file) 1822 result = proc_map_files_instantiate(dir, dentry, task, 1823 (void *)(unsigned long)vma->vm_file->f_mode); 1824 1825 out_no_vma: 1826 up_read(&mm->mmap_sem); 1827 mmput(mm); 1828 out_put_task: 1829 put_task_struct(task); 1830 out: 1831 return ERR_PTR(result); 1832 } 1833 1834 static const struct inode_operations proc_map_files_inode_operations = { 1835 .lookup = proc_map_files_lookup, 1836 .permission = proc_fd_permission, 1837 .setattr = proc_setattr, 1838 }; 1839 1840 static int 1841 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 1842 { 1843 struct vm_area_struct *vma; 1844 struct task_struct *task; 1845 struct mm_struct *mm; 1846 unsigned long nr_files, pos, i; 1847 struct flex_array *fa = NULL; 1848 struct map_files_info info; 1849 struct map_files_info *p; 1850 int ret; 1851 1852 ret = -EPERM; 1853 if (!capable(CAP_SYS_ADMIN)) 1854 goto out; 1855 1856 ret = -ENOENT; 1857 task = get_proc_task(file_inode(file)); 1858 if (!task) 1859 goto out; 1860 1861 ret = -EACCES; 1862 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 1863 goto out_put_task; 1864 1865 ret = 0; 1866 if (!dir_emit_dots(file, ctx)) 1867 goto out_put_task; 1868 1869 mm = get_task_mm(task); 1870 if (!mm) 1871 goto out_put_task; 1872 down_read(&mm->mmap_sem); 1873 1874 nr_files = 0; 1875 1876 /* 1877 * We need two passes here: 1878 * 1879 * 1) Collect vmas of mapped files with mmap_sem taken 1880 * 2) Release mmap_sem and instantiate entries 1881 * 1882 * otherwise we get lockdep complained, since filldir() 1883 * routine might require mmap_sem taken in might_fault(). 1884 */ 1885 1886 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 1887 if (vma->vm_file && ++pos > ctx->pos) 1888 nr_files++; 1889 } 1890 1891 if (nr_files) { 1892 fa = flex_array_alloc(sizeof(info), nr_files, 1893 GFP_KERNEL); 1894 if (!fa || flex_array_prealloc(fa, 0, nr_files, 1895 GFP_KERNEL)) { 1896 ret = -ENOMEM; 1897 if (fa) 1898 flex_array_free(fa); 1899 up_read(&mm->mmap_sem); 1900 mmput(mm); 1901 goto out_put_task; 1902 } 1903 for (i = 0, vma = mm->mmap, pos = 2; vma; 1904 vma = vma->vm_next) { 1905 if (!vma->vm_file) 1906 continue; 1907 if (++pos <= ctx->pos) 1908 continue; 1909 1910 info.mode = vma->vm_file->f_mode; 1911 info.len = snprintf(info.name, 1912 sizeof(info.name), "%lx-%lx", 1913 vma->vm_start, vma->vm_end); 1914 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 1915 BUG(); 1916 } 1917 } 1918 up_read(&mm->mmap_sem); 1919 1920 for (i = 0; i < nr_files; i++) { 1921 p = flex_array_get(fa, i); 1922 if (!proc_fill_cache(file, ctx, 1923 p->name, p->len, 1924 proc_map_files_instantiate, 1925 task, 1926 (void *)(unsigned long)p->mode)) 1927 break; 1928 ctx->pos++; 1929 } 1930 if (fa) 1931 flex_array_free(fa); 1932 mmput(mm); 1933 1934 out_put_task: 1935 put_task_struct(task); 1936 out: 1937 return ret; 1938 } 1939 1940 static const struct file_operations proc_map_files_operations = { 1941 .read = generic_read_dir, 1942 .iterate = proc_map_files_readdir, 1943 .llseek = default_llseek, 1944 }; 1945 1946 struct timers_private { 1947 struct pid *pid; 1948 struct task_struct *task; 1949 struct sighand_struct *sighand; 1950 struct pid_namespace *ns; 1951 unsigned long flags; 1952 }; 1953 1954 static void *timers_start(struct seq_file *m, loff_t *pos) 1955 { 1956 struct timers_private *tp = m->private; 1957 1958 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 1959 if (!tp->task) 1960 return ERR_PTR(-ESRCH); 1961 1962 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 1963 if (!tp->sighand) 1964 return ERR_PTR(-ESRCH); 1965 1966 return seq_list_start(&tp->task->signal->posix_timers, *pos); 1967 } 1968 1969 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 1970 { 1971 struct timers_private *tp = m->private; 1972 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 1973 } 1974 1975 static void timers_stop(struct seq_file *m, void *v) 1976 { 1977 struct timers_private *tp = m->private; 1978 1979 if (tp->sighand) { 1980 unlock_task_sighand(tp->task, &tp->flags); 1981 tp->sighand = NULL; 1982 } 1983 1984 if (tp->task) { 1985 put_task_struct(tp->task); 1986 tp->task = NULL; 1987 } 1988 } 1989 1990 static int show_timer(struct seq_file *m, void *v) 1991 { 1992 struct k_itimer *timer; 1993 struct timers_private *tp = m->private; 1994 int notify; 1995 static const char * const nstr[] = { 1996 [SIGEV_SIGNAL] = "signal", 1997 [SIGEV_NONE] = "none", 1998 [SIGEV_THREAD] = "thread", 1999 }; 2000 2001 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2002 notify = timer->it_sigev_notify; 2003 2004 seq_printf(m, "ID: %d\n", timer->it_id); 2005 seq_printf(m, "signal: %d/%p\n", timer->sigq->info.si_signo, 2006 timer->sigq->info.si_value.sival_ptr); 2007 seq_printf(m, "notify: %s/%s.%d\n", 2008 nstr[notify & ~SIGEV_THREAD_ID], 2009 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2010 pid_nr_ns(timer->it_pid, tp->ns)); 2011 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2012 2013 return 0; 2014 } 2015 2016 static const struct seq_operations proc_timers_seq_ops = { 2017 .start = timers_start, 2018 .next = timers_next, 2019 .stop = timers_stop, 2020 .show = show_timer, 2021 }; 2022 2023 static int proc_timers_open(struct inode *inode, struct file *file) 2024 { 2025 struct timers_private *tp; 2026 2027 tp = __seq_open_private(file, &proc_timers_seq_ops, 2028 sizeof(struct timers_private)); 2029 if (!tp) 2030 return -ENOMEM; 2031 2032 tp->pid = proc_pid(inode); 2033 tp->ns = inode->i_sb->s_fs_info; 2034 return 0; 2035 } 2036 2037 static const struct file_operations proc_timers_operations = { 2038 .open = proc_timers_open, 2039 .read = seq_read, 2040 .llseek = seq_lseek, 2041 .release = seq_release_private, 2042 }; 2043 #endif /* CONFIG_CHECKPOINT_RESTORE */ 2044 2045 static int proc_pident_instantiate(struct inode *dir, 2046 struct dentry *dentry, struct task_struct *task, const void *ptr) 2047 { 2048 const struct pid_entry *p = ptr; 2049 struct inode *inode; 2050 struct proc_inode *ei; 2051 2052 inode = proc_pid_make_inode(dir->i_sb, task); 2053 if (!inode) 2054 goto out; 2055 2056 ei = PROC_I(inode); 2057 inode->i_mode = p->mode; 2058 if (S_ISDIR(inode->i_mode)) 2059 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2060 if (p->iop) 2061 inode->i_op = p->iop; 2062 if (p->fop) 2063 inode->i_fop = p->fop; 2064 ei->op = p->op; 2065 d_set_d_op(dentry, &pid_dentry_operations); 2066 d_add(dentry, inode); 2067 /* Close the race of the process dying before we return the dentry */ 2068 if (pid_revalidate(dentry, 0)) 2069 return 0; 2070 out: 2071 return -ENOENT; 2072 } 2073 2074 static struct dentry *proc_pident_lookup(struct inode *dir, 2075 struct dentry *dentry, 2076 const struct pid_entry *ents, 2077 unsigned int nents) 2078 { 2079 int error; 2080 struct task_struct *task = get_proc_task(dir); 2081 const struct pid_entry *p, *last; 2082 2083 error = -ENOENT; 2084 2085 if (!task) 2086 goto out_no_task; 2087 2088 /* 2089 * Yes, it does not scale. And it should not. Don't add 2090 * new entries into /proc/<tgid>/ without very good reasons. 2091 */ 2092 last = &ents[nents - 1]; 2093 for (p = ents; p <= last; p++) { 2094 if (p->len != dentry->d_name.len) 2095 continue; 2096 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2097 break; 2098 } 2099 if (p > last) 2100 goto out; 2101 2102 error = proc_pident_instantiate(dir, dentry, task, p); 2103 out: 2104 put_task_struct(task); 2105 out_no_task: 2106 return ERR_PTR(error); 2107 } 2108 2109 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2110 const struct pid_entry *ents, unsigned int nents) 2111 { 2112 struct task_struct *task = get_proc_task(file_inode(file)); 2113 const struct pid_entry *p; 2114 2115 if (!task) 2116 return -ENOENT; 2117 2118 if (!dir_emit_dots(file, ctx)) 2119 goto out; 2120 2121 if (ctx->pos >= nents + 2) 2122 goto out; 2123 2124 for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) { 2125 if (!proc_fill_cache(file, ctx, p->name, p->len, 2126 proc_pident_instantiate, task, p)) 2127 break; 2128 ctx->pos++; 2129 } 2130 out: 2131 put_task_struct(task); 2132 return 0; 2133 } 2134 2135 #ifdef CONFIG_SECURITY 2136 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2137 size_t count, loff_t *ppos) 2138 { 2139 struct inode * inode = file_inode(file); 2140 char *p = NULL; 2141 ssize_t length; 2142 struct task_struct *task = get_proc_task(inode); 2143 2144 if (!task) 2145 return -ESRCH; 2146 2147 length = security_getprocattr(task, 2148 (char*)file->f_path.dentry->d_name.name, 2149 &p); 2150 put_task_struct(task); 2151 if (length > 0) 2152 length = simple_read_from_buffer(buf, count, ppos, p, length); 2153 kfree(p); 2154 return length; 2155 } 2156 2157 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2158 size_t count, loff_t *ppos) 2159 { 2160 struct inode * inode = file_inode(file); 2161 char *page; 2162 ssize_t length; 2163 struct task_struct *task = get_proc_task(inode); 2164 2165 length = -ESRCH; 2166 if (!task) 2167 goto out_no_task; 2168 if (count > PAGE_SIZE) 2169 count = PAGE_SIZE; 2170 2171 /* No partial writes. */ 2172 length = -EINVAL; 2173 if (*ppos != 0) 2174 goto out; 2175 2176 length = -ENOMEM; 2177 page = (char*)__get_free_page(GFP_TEMPORARY); 2178 if (!page) 2179 goto out; 2180 2181 length = -EFAULT; 2182 if (copy_from_user(page, buf, count)) 2183 goto out_free; 2184 2185 /* Guard against adverse ptrace interaction */ 2186 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex); 2187 if (length < 0) 2188 goto out_free; 2189 2190 length = security_setprocattr(task, 2191 (char*)file->f_path.dentry->d_name.name, 2192 (void*)page, count); 2193 mutex_unlock(&task->signal->cred_guard_mutex); 2194 out_free: 2195 free_page((unsigned long) page); 2196 out: 2197 put_task_struct(task); 2198 out_no_task: 2199 return length; 2200 } 2201 2202 static const struct file_operations proc_pid_attr_operations = { 2203 .read = proc_pid_attr_read, 2204 .write = proc_pid_attr_write, 2205 .llseek = generic_file_llseek, 2206 }; 2207 2208 static const struct pid_entry attr_dir_stuff[] = { 2209 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2210 REG("prev", S_IRUGO, proc_pid_attr_operations), 2211 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2212 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2213 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2214 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2215 }; 2216 2217 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2218 { 2219 return proc_pident_readdir(file, ctx, 2220 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2221 } 2222 2223 static const struct file_operations proc_attr_dir_operations = { 2224 .read = generic_read_dir, 2225 .iterate = proc_attr_dir_readdir, 2226 .llseek = default_llseek, 2227 }; 2228 2229 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2230 struct dentry *dentry, unsigned int flags) 2231 { 2232 return proc_pident_lookup(dir, dentry, 2233 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2234 } 2235 2236 static const struct inode_operations proc_attr_dir_inode_operations = { 2237 .lookup = proc_attr_dir_lookup, 2238 .getattr = pid_getattr, 2239 .setattr = proc_setattr, 2240 }; 2241 2242 #endif 2243 2244 #ifdef CONFIG_ELF_CORE 2245 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2246 size_t count, loff_t *ppos) 2247 { 2248 struct task_struct *task = get_proc_task(file_inode(file)); 2249 struct mm_struct *mm; 2250 char buffer[PROC_NUMBUF]; 2251 size_t len; 2252 int ret; 2253 2254 if (!task) 2255 return -ESRCH; 2256 2257 ret = 0; 2258 mm = get_task_mm(task); 2259 if (mm) { 2260 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2261 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2262 MMF_DUMP_FILTER_SHIFT)); 2263 mmput(mm); 2264 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2265 } 2266 2267 put_task_struct(task); 2268 2269 return ret; 2270 } 2271 2272 static ssize_t proc_coredump_filter_write(struct file *file, 2273 const char __user *buf, 2274 size_t count, 2275 loff_t *ppos) 2276 { 2277 struct task_struct *task; 2278 struct mm_struct *mm; 2279 char buffer[PROC_NUMBUF], *end; 2280 unsigned int val; 2281 int ret; 2282 int i; 2283 unsigned long mask; 2284 2285 ret = -EFAULT; 2286 memset(buffer, 0, sizeof(buffer)); 2287 if (count > sizeof(buffer) - 1) 2288 count = sizeof(buffer) - 1; 2289 if (copy_from_user(buffer, buf, count)) 2290 goto out_no_task; 2291 2292 ret = -EINVAL; 2293 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2294 if (*end == '\n') 2295 end++; 2296 if (end - buffer == 0) 2297 goto out_no_task; 2298 2299 ret = -ESRCH; 2300 task = get_proc_task(file_inode(file)); 2301 if (!task) 2302 goto out_no_task; 2303 2304 ret = end - buffer; 2305 mm = get_task_mm(task); 2306 if (!mm) 2307 goto out_no_mm; 2308 2309 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2310 if (val & mask) 2311 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2312 else 2313 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2314 } 2315 2316 mmput(mm); 2317 out_no_mm: 2318 put_task_struct(task); 2319 out_no_task: 2320 return ret; 2321 } 2322 2323 static const struct file_operations proc_coredump_filter_operations = { 2324 .read = proc_coredump_filter_read, 2325 .write = proc_coredump_filter_write, 2326 .llseek = generic_file_llseek, 2327 }; 2328 #endif 2329 2330 #ifdef CONFIG_TASK_IO_ACCOUNTING 2331 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2332 { 2333 struct task_io_accounting acct = task->ioac; 2334 unsigned long flags; 2335 int result; 2336 2337 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2338 if (result) 2339 return result; 2340 2341 if (!ptrace_may_access(task, PTRACE_MODE_READ)) { 2342 result = -EACCES; 2343 goto out_unlock; 2344 } 2345 2346 if (whole && lock_task_sighand(task, &flags)) { 2347 struct task_struct *t = task; 2348 2349 task_io_accounting_add(&acct, &task->signal->ioac); 2350 while_each_thread(task, t) 2351 task_io_accounting_add(&acct, &t->ioac); 2352 2353 unlock_task_sighand(task, &flags); 2354 } 2355 result = seq_printf(m, 2356 "rchar: %llu\n" 2357 "wchar: %llu\n" 2358 "syscr: %llu\n" 2359 "syscw: %llu\n" 2360 "read_bytes: %llu\n" 2361 "write_bytes: %llu\n" 2362 "cancelled_write_bytes: %llu\n", 2363 (unsigned long long)acct.rchar, 2364 (unsigned long long)acct.wchar, 2365 (unsigned long long)acct.syscr, 2366 (unsigned long long)acct.syscw, 2367 (unsigned long long)acct.read_bytes, 2368 (unsigned long long)acct.write_bytes, 2369 (unsigned long long)acct.cancelled_write_bytes); 2370 out_unlock: 2371 mutex_unlock(&task->signal->cred_guard_mutex); 2372 return result; 2373 } 2374 2375 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2376 struct pid *pid, struct task_struct *task) 2377 { 2378 return do_io_accounting(task, m, 0); 2379 } 2380 2381 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2382 struct pid *pid, struct task_struct *task) 2383 { 2384 return do_io_accounting(task, m, 1); 2385 } 2386 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2387 2388 #ifdef CONFIG_USER_NS 2389 static int proc_id_map_open(struct inode *inode, struct file *file, 2390 const struct seq_operations *seq_ops) 2391 { 2392 struct user_namespace *ns = NULL; 2393 struct task_struct *task; 2394 struct seq_file *seq; 2395 int ret = -EINVAL; 2396 2397 task = get_proc_task(inode); 2398 if (task) { 2399 rcu_read_lock(); 2400 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2401 rcu_read_unlock(); 2402 put_task_struct(task); 2403 } 2404 if (!ns) 2405 goto err; 2406 2407 ret = seq_open(file, seq_ops); 2408 if (ret) 2409 goto err_put_ns; 2410 2411 seq = file->private_data; 2412 seq->private = ns; 2413 2414 return 0; 2415 err_put_ns: 2416 put_user_ns(ns); 2417 err: 2418 return ret; 2419 } 2420 2421 static int proc_id_map_release(struct inode *inode, struct file *file) 2422 { 2423 struct seq_file *seq = file->private_data; 2424 struct user_namespace *ns = seq->private; 2425 put_user_ns(ns); 2426 return seq_release(inode, file); 2427 } 2428 2429 static int proc_uid_map_open(struct inode *inode, struct file *file) 2430 { 2431 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2432 } 2433 2434 static int proc_gid_map_open(struct inode *inode, struct file *file) 2435 { 2436 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2437 } 2438 2439 static int proc_projid_map_open(struct inode *inode, struct file *file) 2440 { 2441 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2442 } 2443 2444 static const struct file_operations proc_uid_map_operations = { 2445 .open = proc_uid_map_open, 2446 .write = proc_uid_map_write, 2447 .read = seq_read, 2448 .llseek = seq_lseek, 2449 .release = proc_id_map_release, 2450 }; 2451 2452 static const struct file_operations proc_gid_map_operations = { 2453 .open = proc_gid_map_open, 2454 .write = proc_gid_map_write, 2455 .read = seq_read, 2456 .llseek = seq_lseek, 2457 .release = proc_id_map_release, 2458 }; 2459 2460 static const struct file_operations proc_projid_map_operations = { 2461 .open = proc_projid_map_open, 2462 .write = proc_projid_map_write, 2463 .read = seq_read, 2464 .llseek = seq_lseek, 2465 .release = proc_id_map_release, 2466 }; 2467 2468 static int proc_setgroups_open(struct inode *inode, struct file *file) 2469 { 2470 struct user_namespace *ns = NULL; 2471 struct task_struct *task; 2472 int ret; 2473 2474 ret = -ESRCH; 2475 task = get_proc_task(inode); 2476 if (task) { 2477 rcu_read_lock(); 2478 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2479 rcu_read_unlock(); 2480 put_task_struct(task); 2481 } 2482 if (!ns) 2483 goto err; 2484 2485 if (file->f_mode & FMODE_WRITE) { 2486 ret = -EACCES; 2487 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2488 goto err_put_ns; 2489 } 2490 2491 ret = single_open(file, &proc_setgroups_show, ns); 2492 if (ret) 2493 goto err_put_ns; 2494 2495 return 0; 2496 err_put_ns: 2497 put_user_ns(ns); 2498 err: 2499 return ret; 2500 } 2501 2502 static int proc_setgroups_release(struct inode *inode, struct file *file) 2503 { 2504 struct seq_file *seq = file->private_data; 2505 struct user_namespace *ns = seq->private; 2506 int ret = single_release(inode, file); 2507 put_user_ns(ns); 2508 return ret; 2509 } 2510 2511 static const struct file_operations proc_setgroups_operations = { 2512 .open = proc_setgroups_open, 2513 .write = proc_setgroups_write, 2514 .read = seq_read, 2515 .llseek = seq_lseek, 2516 .release = proc_setgroups_release, 2517 }; 2518 #endif /* CONFIG_USER_NS */ 2519 2520 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2521 struct pid *pid, struct task_struct *task) 2522 { 2523 int err = lock_trace(task); 2524 if (!err) { 2525 seq_printf(m, "%08x\n", task->personality); 2526 unlock_trace(task); 2527 } 2528 return err; 2529 } 2530 2531 /* 2532 * Thread groups 2533 */ 2534 static const struct file_operations proc_task_operations; 2535 static const struct inode_operations proc_task_inode_operations; 2536 2537 static const struct pid_entry tgid_base_stuff[] = { 2538 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2539 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2540 #ifdef CONFIG_CHECKPOINT_RESTORE 2541 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2542 #endif 2543 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2544 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2545 #ifdef CONFIG_NET 2546 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2547 #endif 2548 REG("environ", S_IRUSR, proc_environ_operations), 2549 ONE("auxv", S_IRUSR, proc_pid_auxv), 2550 ONE("status", S_IRUGO, proc_pid_status), 2551 ONE("personality", S_IRUSR, proc_pid_personality), 2552 ONE("limits", S_IRUGO, proc_pid_limits), 2553 #ifdef CONFIG_SCHED_DEBUG 2554 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2555 #endif 2556 #ifdef CONFIG_SCHED_AUTOGROUP 2557 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2558 #endif 2559 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2560 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2561 ONE("syscall", S_IRUSR, proc_pid_syscall), 2562 #endif 2563 ONE("cmdline", S_IRUGO, proc_pid_cmdline), 2564 ONE("stat", S_IRUGO, proc_tgid_stat), 2565 ONE("statm", S_IRUGO, proc_pid_statm), 2566 REG("maps", S_IRUGO, proc_pid_maps_operations), 2567 #ifdef CONFIG_NUMA 2568 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2569 #endif 2570 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2571 LNK("cwd", proc_cwd_link), 2572 LNK("root", proc_root_link), 2573 LNK("exe", proc_exe_link), 2574 REG("mounts", S_IRUGO, proc_mounts_operations), 2575 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2576 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2577 #ifdef CONFIG_PROC_PAGE_MONITOR 2578 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2579 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2580 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2581 #endif 2582 #ifdef CONFIG_SECURITY 2583 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2584 #endif 2585 #ifdef CONFIG_KALLSYMS 2586 ONE("wchan", S_IRUGO, proc_pid_wchan), 2587 #endif 2588 #ifdef CONFIG_STACKTRACE 2589 ONE("stack", S_IRUSR, proc_pid_stack), 2590 #endif 2591 #ifdef CONFIG_SCHEDSTATS 2592 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2593 #endif 2594 #ifdef CONFIG_LATENCYTOP 2595 REG("latency", S_IRUGO, proc_lstats_operations), 2596 #endif 2597 #ifdef CONFIG_PROC_PID_CPUSET 2598 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2599 #endif 2600 #ifdef CONFIG_CGROUPS 2601 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2602 #endif 2603 ONE("oom_score", S_IRUGO, proc_oom_score), 2604 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2605 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2606 #ifdef CONFIG_AUDITSYSCALL 2607 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2608 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2609 #endif 2610 #ifdef CONFIG_FAULT_INJECTION 2611 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2612 #endif 2613 #ifdef CONFIG_ELF_CORE 2614 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2615 #endif 2616 #ifdef CONFIG_TASK_IO_ACCOUNTING 2617 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2618 #endif 2619 #ifdef CONFIG_HARDWALL 2620 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 2621 #endif 2622 #ifdef CONFIG_USER_NS 2623 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2624 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2625 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2626 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2627 #endif 2628 #ifdef CONFIG_CHECKPOINT_RESTORE 2629 REG("timers", S_IRUGO, proc_timers_operations), 2630 #endif 2631 }; 2632 2633 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 2634 { 2635 return proc_pident_readdir(file, ctx, 2636 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2637 } 2638 2639 static const struct file_operations proc_tgid_base_operations = { 2640 .read = generic_read_dir, 2641 .iterate = proc_tgid_base_readdir, 2642 .llseek = default_llseek, 2643 }; 2644 2645 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 2646 { 2647 return proc_pident_lookup(dir, dentry, 2648 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2649 } 2650 2651 static const struct inode_operations proc_tgid_base_inode_operations = { 2652 .lookup = proc_tgid_base_lookup, 2653 .getattr = pid_getattr, 2654 .setattr = proc_setattr, 2655 .permission = proc_pid_permission, 2656 }; 2657 2658 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2659 { 2660 struct dentry *dentry, *leader, *dir; 2661 char buf[PROC_NUMBUF]; 2662 struct qstr name; 2663 2664 name.name = buf; 2665 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2666 /* no ->d_hash() rejects on procfs */ 2667 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2668 if (dentry) { 2669 d_invalidate(dentry); 2670 dput(dentry); 2671 } 2672 2673 if (pid == tgid) 2674 return; 2675 2676 name.name = buf; 2677 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2678 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2679 if (!leader) 2680 goto out; 2681 2682 name.name = "task"; 2683 name.len = strlen(name.name); 2684 dir = d_hash_and_lookup(leader, &name); 2685 if (!dir) 2686 goto out_put_leader; 2687 2688 name.name = buf; 2689 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2690 dentry = d_hash_and_lookup(dir, &name); 2691 if (dentry) { 2692 d_invalidate(dentry); 2693 dput(dentry); 2694 } 2695 2696 dput(dir); 2697 out_put_leader: 2698 dput(leader); 2699 out: 2700 return; 2701 } 2702 2703 /** 2704 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2705 * @task: task that should be flushed. 2706 * 2707 * When flushing dentries from proc, one needs to flush them from global 2708 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2709 * in. This call is supposed to do all of this job. 2710 * 2711 * Looks in the dcache for 2712 * /proc/@pid 2713 * /proc/@tgid/task/@pid 2714 * if either directory is present flushes it and all of it'ts children 2715 * from the dcache. 2716 * 2717 * It is safe and reasonable to cache /proc entries for a task until 2718 * that task exits. After that they just clog up the dcache with 2719 * useless entries, possibly causing useful dcache entries to be 2720 * flushed instead. This routine is proved to flush those useless 2721 * dcache entries at process exit time. 2722 * 2723 * NOTE: This routine is just an optimization so it does not guarantee 2724 * that no dcache entries will exist at process exit time it 2725 * just makes it very unlikely that any will persist. 2726 */ 2727 2728 void proc_flush_task(struct task_struct *task) 2729 { 2730 int i; 2731 struct pid *pid, *tgid; 2732 struct upid *upid; 2733 2734 pid = task_pid(task); 2735 tgid = task_tgid(task); 2736 2737 for (i = 0; i <= pid->level; i++) { 2738 upid = &pid->numbers[i]; 2739 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2740 tgid->numbers[i].nr); 2741 } 2742 } 2743 2744 static int proc_pid_instantiate(struct inode *dir, 2745 struct dentry * dentry, 2746 struct task_struct *task, const void *ptr) 2747 { 2748 struct inode *inode; 2749 2750 inode = proc_pid_make_inode(dir->i_sb, task); 2751 if (!inode) 2752 goto out; 2753 2754 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2755 inode->i_op = &proc_tgid_base_inode_operations; 2756 inode->i_fop = &proc_tgid_base_operations; 2757 inode->i_flags|=S_IMMUTABLE; 2758 2759 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff, 2760 ARRAY_SIZE(tgid_base_stuff))); 2761 2762 d_set_d_op(dentry, &pid_dentry_operations); 2763 2764 d_add(dentry, inode); 2765 /* Close the race of the process dying before we return the dentry */ 2766 if (pid_revalidate(dentry, 0)) 2767 return 0; 2768 out: 2769 return -ENOENT; 2770 } 2771 2772 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 2773 { 2774 int result = -ENOENT; 2775 struct task_struct *task; 2776 unsigned tgid; 2777 struct pid_namespace *ns; 2778 2779 tgid = name_to_int(&dentry->d_name); 2780 if (tgid == ~0U) 2781 goto out; 2782 2783 ns = dentry->d_sb->s_fs_info; 2784 rcu_read_lock(); 2785 task = find_task_by_pid_ns(tgid, ns); 2786 if (task) 2787 get_task_struct(task); 2788 rcu_read_unlock(); 2789 if (!task) 2790 goto out; 2791 2792 result = proc_pid_instantiate(dir, dentry, task, NULL); 2793 put_task_struct(task); 2794 out: 2795 return ERR_PTR(result); 2796 } 2797 2798 /* 2799 * Find the first task with tgid >= tgid 2800 * 2801 */ 2802 struct tgid_iter { 2803 unsigned int tgid; 2804 struct task_struct *task; 2805 }; 2806 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 2807 { 2808 struct pid *pid; 2809 2810 if (iter.task) 2811 put_task_struct(iter.task); 2812 rcu_read_lock(); 2813 retry: 2814 iter.task = NULL; 2815 pid = find_ge_pid(iter.tgid, ns); 2816 if (pid) { 2817 iter.tgid = pid_nr_ns(pid, ns); 2818 iter.task = pid_task(pid, PIDTYPE_PID); 2819 /* What we to know is if the pid we have find is the 2820 * pid of a thread_group_leader. Testing for task 2821 * being a thread_group_leader is the obvious thing 2822 * todo but there is a window when it fails, due to 2823 * the pid transfer logic in de_thread. 2824 * 2825 * So we perform the straight forward test of seeing 2826 * if the pid we have found is the pid of a thread 2827 * group leader, and don't worry if the task we have 2828 * found doesn't happen to be a thread group leader. 2829 * As we don't care in the case of readdir. 2830 */ 2831 if (!iter.task || !has_group_leader_pid(iter.task)) { 2832 iter.tgid += 1; 2833 goto retry; 2834 } 2835 get_task_struct(iter.task); 2836 } 2837 rcu_read_unlock(); 2838 return iter; 2839 } 2840 2841 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 2842 2843 /* for the /proc/ directory itself, after non-process stuff has been done */ 2844 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 2845 { 2846 struct tgid_iter iter; 2847 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info; 2848 loff_t pos = ctx->pos; 2849 2850 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 2851 return 0; 2852 2853 if (pos == TGID_OFFSET - 2) { 2854 struct inode *inode = ns->proc_self->d_inode; 2855 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 2856 return 0; 2857 ctx->pos = pos = pos + 1; 2858 } 2859 if (pos == TGID_OFFSET - 1) { 2860 struct inode *inode = ns->proc_thread_self->d_inode; 2861 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 2862 return 0; 2863 ctx->pos = pos = pos + 1; 2864 } 2865 iter.tgid = pos - TGID_OFFSET; 2866 iter.task = NULL; 2867 for (iter = next_tgid(ns, iter); 2868 iter.task; 2869 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2870 char name[PROC_NUMBUF]; 2871 int len; 2872 if (!has_pid_permissions(ns, iter.task, 2)) 2873 continue; 2874 2875 len = snprintf(name, sizeof(name), "%d", iter.tgid); 2876 ctx->pos = iter.tgid + TGID_OFFSET; 2877 if (!proc_fill_cache(file, ctx, name, len, 2878 proc_pid_instantiate, iter.task, NULL)) { 2879 put_task_struct(iter.task); 2880 return 0; 2881 } 2882 } 2883 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 2884 return 0; 2885 } 2886 2887 /* 2888 * Tasks 2889 */ 2890 static const struct pid_entry tid_base_stuff[] = { 2891 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2892 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2893 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2894 #ifdef CONFIG_NET 2895 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2896 #endif 2897 REG("environ", S_IRUSR, proc_environ_operations), 2898 ONE("auxv", S_IRUSR, proc_pid_auxv), 2899 ONE("status", S_IRUGO, proc_pid_status), 2900 ONE("personality", S_IRUSR, proc_pid_personality), 2901 ONE("limits", S_IRUGO, proc_pid_limits), 2902 #ifdef CONFIG_SCHED_DEBUG 2903 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2904 #endif 2905 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2906 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2907 ONE("syscall", S_IRUSR, proc_pid_syscall), 2908 #endif 2909 ONE("cmdline", S_IRUGO, proc_pid_cmdline), 2910 ONE("stat", S_IRUGO, proc_tid_stat), 2911 ONE("statm", S_IRUGO, proc_pid_statm), 2912 REG("maps", S_IRUGO, proc_tid_maps_operations), 2913 #ifdef CONFIG_CHECKPOINT_RESTORE 2914 REG("children", S_IRUGO, proc_tid_children_operations), 2915 #endif 2916 #ifdef CONFIG_NUMA 2917 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 2918 #endif 2919 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2920 LNK("cwd", proc_cwd_link), 2921 LNK("root", proc_root_link), 2922 LNK("exe", proc_exe_link), 2923 REG("mounts", S_IRUGO, proc_mounts_operations), 2924 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2925 #ifdef CONFIG_PROC_PAGE_MONITOR 2926 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2927 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 2928 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2929 #endif 2930 #ifdef CONFIG_SECURITY 2931 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2932 #endif 2933 #ifdef CONFIG_KALLSYMS 2934 ONE("wchan", S_IRUGO, proc_pid_wchan), 2935 #endif 2936 #ifdef CONFIG_STACKTRACE 2937 ONE("stack", S_IRUSR, proc_pid_stack), 2938 #endif 2939 #ifdef CONFIG_SCHEDSTATS 2940 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2941 #endif 2942 #ifdef CONFIG_LATENCYTOP 2943 REG("latency", S_IRUGO, proc_lstats_operations), 2944 #endif 2945 #ifdef CONFIG_PROC_PID_CPUSET 2946 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2947 #endif 2948 #ifdef CONFIG_CGROUPS 2949 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2950 #endif 2951 ONE("oom_score", S_IRUGO, proc_oom_score), 2952 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2953 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2954 #ifdef CONFIG_AUDITSYSCALL 2955 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2956 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2957 #endif 2958 #ifdef CONFIG_FAULT_INJECTION 2959 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2960 #endif 2961 #ifdef CONFIG_TASK_IO_ACCOUNTING 2962 ONE("io", S_IRUSR, proc_tid_io_accounting), 2963 #endif 2964 #ifdef CONFIG_HARDWALL 2965 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 2966 #endif 2967 #ifdef CONFIG_USER_NS 2968 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2969 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2970 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2971 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2972 #endif 2973 }; 2974 2975 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 2976 { 2977 return proc_pident_readdir(file, ctx, 2978 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2979 } 2980 2981 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 2982 { 2983 return proc_pident_lookup(dir, dentry, 2984 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2985 } 2986 2987 static const struct file_operations proc_tid_base_operations = { 2988 .read = generic_read_dir, 2989 .iterate = proc_tid_base_readdir, 2990 .llseek = default_llseek, 2991 }; 2992 2993 static const struct inode_operations proc_tid_base_inode_operations = { 2994 .lookup = proc_tid_base_lookup, 2995 .getattr = pid_getattr, 2996 .setattr = proc_setattr, 2997 }; 2998 2999 static int proc_task_instantiate(struct inode *dir, 3000 struct dentry *dentry, struct task_struct *task, const void *ptr) 3001 { 3002 struct inode *inode; 3003 inode = proc_pid_make_inode(dir->i_sb, task); 3004 3005 if (!inode) 3006 goto out; 3007 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 3008 inode->i_op = &proc_tid_base_inode_operations; 3009 inode->i_fop = &proc_tid_base_operations; 3010 inode->i_flags|=S_IMMUTABLE; 3011 3012 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff, 3013 ARRAY_SIZE(tid_base_stuff))); 3014 3015 d_set_d_op(dentry, &pid_dentry_operations); 3016 3017 d_add(dentry, inode); 3018 /* Close the race of the process dying before we return the dentry */ 3019 if (pid_revalidate(dentry, 0)) 3020 return 0; 3021 out: 3022 return -ENOENT; 3023 } 3024 3025 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3026 { 3027 int result = -ENOENT; 3028 struct task_struct *task; 3029 struct task_struct *leader = get_proc_task(dir); 3030 unsigned tid; 3031 struct pid_namespace *ns; 3032 3033 if (!leader) 3034 goto out_no_task; 3035 3036 tid = name_to_int(&dentry->d_name); 3037 if (tid == ~0U) 3038 goto out; 3039 3040 ns = dentry->d_sb->s_fs_info; 3041 rcu_read_lock(); 3042 task = find_task_by_pid_ns(tid, ns); 3043 if (task) 3044 get_task_struct(task); 3045 rcu_read_unlock(); 3046 if (!task) 3047 goto out; 3048 if (!same_thread_group(leader, task)) 3049 goto out_drop_task; 3050 3051 result = proc_task_instantiate(dir, dentry, task, NULL); 3052 out_drop_task: 3053 put_task_struct(task); 3054 out: 3055 put_task_struct(leader); 3056 out_no_task: 3057 return ERR_PTR(result); 3058 } 3059 3060 /* 3061 * Find the first tid of a thread group to return to user space. 3062 * 3063 * Usually this is just the thread group leader, but if the users 3064 * buffer was too small or there was a seek into the middle of the 3065 * directory we have more work todo. 3066 * 3067 * In the case of a short read we start with find_task_by_pid. 3068 * 3069 * In the case of a seek we start with the leader and walk nr 3070 * threads past it. 3071 */ 3072 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3073 struct pid_namespace *ns) 3074 { 3075 struct task_struct *pos, *task; 3076 unsigned long nr = f_pos; 3077 3078 if (nr != f_pos) /* 32bit overflow? */ 3079 return NULL; 3080 3081 rcu_read_lock(); 3082 task = pid_task(pid, PIDTYPE_PID); 3083 if (!task) 3084 goto fail; 3085 3086 /* Attempt to start with the tid of a thread */ 3087 if (tid && nr) { 3088 pos = find_task_by_pid_ns(tid, ns); 3089 if (pos && same_thread_group(pos, task)) 3090 goto found; 3091 } 3092 3093 /* If nr exceeds the number of threads there is nothing todo */ 3094 if (nr >= get_nr_threads(task)) 3095 goto fail; 3096 3097 /* If we haven't found our starting place yet start 3098 * with the leader and walk nr threads forward. 3099 */ 3100 pos = task = task->group_leader; 3101 do { 3102 if (!nr--) 3103 goto found; 3104 } while_each_thread(task, pos); 3105 fail: 3106 pos = NULL; 3107 goto out; 3108 found: 3109 get_task_struct(pos); 3110 out: 3111 rcu_read_unlock(); 3112 return pos; 3113 } 3114 3115 /* 3116 * Find the next thread in the thread list. 3117 * Return NULL if there is an error or no next thread. 3118 * 3119 * The reference to the input task_struct is released. 3120 */ 3121 static struct task_struct *next_tid(struct task_struct *start) 3122 { 3123 struct task_struct *pos = NULL; 3124 rcu_read_lock(); 3125 if (pid_alive(start)) { 3126 pos = next_thread(start); 3127 if (thread_group_leader(pos)) 3128 pos = NULL; 3129 else 3130 get_task_struct(pos); 3131 } 3132 rcu_read_unlock(); 3133 put_task_struct(start); 3134 return pos; 3135 } 3136 3137 /* for the /proc/TGID/task/ directories */ 3138 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3139 { 3140 struct inode *inode = file_inode(file); 3141 struct task_struct *task; 3142 struct pid_namespace *ns; 3143 int tid; 3144 3145 if (proc_inode_is_dead(inode)) 3146 return -ENOENT; 3147 3148 if (!dir_emit_dots(file, ctx)) 3149 return 0; 3150 3151 /* f_version caches the tgid value that the last readdir call couldn't 3152 * return. lseek aka telldir automagically resets f_version to 0. 3153 */ 3154 ns = inode->i_sb->s_fs_info; 3155 tid = (int)file->f_version; 3156 file->f_version = 0; 3157 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3158 task; 3159 task = next_tid(task), ctx->pos++) { 3160 char name[PROC_NUMBUF]; 3161 int len; 3162 tid = task_pid_nr_ns(task, ns); 3163 len = snprintf(name, sizeof(name), "%d", tid); 3164 if (!proc_fill_cache(file, ctx, name, len, 3165 proc_task_instantiate, task, NULL)) { 3166 /* returning this tgid failed, save it as the first 3167 * pid for the next readir call */ 3168 file->f_version = (u64)tid; 3169 put_task_struct(task); 3170 break; 3171 } 3172 } 3173 3174 return 0; 3175 } 3176 3177 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 3178 { 3179 struct inode *inode = dentry->d_inode; 3180 struct task_struct *p = get_proc_task(inode); 3181 generic_fillattr(inode, stat); 3182 3183 if (p) { 3184 stat->nlink += get_nr_threads(p); 3185 put_task_struct(p); 3186 } 3187 3188 return 0; 3189 } 3190 3191 static const struct inode_operations proc_task_inode_operations = { 3192 .lookup = proc_task_lookup, 3193 .getattr = proc_task_getattr, 3194 .setattr = proc_setattr, 3195 .permission = proc_pid_permission, 3196 }; 3197 3198 static const struct file_operations proc_task_operations = { 3199 .read = generic_read_dir, 3200 .iterate = proc_task_readdir, 3201 .llseek = default_llseek, 3202 }; 3203