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