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/cgroup.h> 77 #include <linux/cpuset.h> 78 #include <linux/audit.h> 79 #include <linux/poll.h> 80 #include <linux/nsproxy.h> 81 #include <linux/oom.h> 82 #include <linux/elf.h> 83 #include <linux/pid_namespace.h> 84 #include <linux/user_namespace.h> 85 #include <linux/fs_struct.h> 86 #include <linux/slab.h> 87 #include <linux/flex_array.h> 88 #ifdef CONFIG_HARDWALL 89 #include <asm/hardwall.h> 90 #endif 91 #include <trace/events/oom.h> 92 #include "internal.h" 93 #include "fd.h" 94 95 /* NOTE: 96 * Implementing inode permission operations in /proc is almost 97 * certainly an error. Permission checks need to happen during 98 * each system call not at open time. The reason is that most of 99 * what we wish to check for permissions in /proc varies at runtime. 100 * 101 * The classic example of a problem is opening file descriptors 102 * in /proc for a task before it execs a suid executable. 103 */ 104 105 struct pid_entry { 106 char *name; 107 int len; 108 umode_t mode; 109 const struct inode_operations *iop; 110 const struct file_operations *fop; 111 union proc_op op; 112 }; 113 114 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 115 .name = (NAME), \ 116 .len = sizeof(NAME) - 1, \ 117 .mode = MODE, \ 118 .iop = IOP, \ 119 .fop = FOP, \ 120 .op = OP, \ 121 } 122 123 #define DIR(NAME, MODE, iops, fops) \ 124 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 125 #define LNK(NAME, get_link) \ 126 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 127 &proc_pid_link_inode_operations, NULL, \ 128 { .proc_get_link = get_link } ) 129 #define REG(NAME, MODE, fops) \ 130 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 131 #define INF(NAME, MODE, read) \ 132 NOD(NAME, (S_IFREG|(MODE)), \ 133 NULL, &proc_info_file_operations, \ 134 { .proc_read = read } ) 135 #define ONE(NAME, MODE, show) \ 136 NOD(NAME, (S_IFREG|(MODE)), \ 137 NULL, &proc_single_file_operations, \ 138 { .proc_show = show } ) 139 140 /* 141 * Count the number of hardlinks for the pid_entry table, excluding the . 142 * and .. links. 143 */ 144 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, 145 unsigned int n) 146 { 147 unsigned int i; 148 unsigned int count; 149 150 count = 0; 151 for (i = 0; i < n; ++i) { 152 if (S_ISDIR(entries[i].mode)) 153 ++count; 154 } 155 156 return count; 157 } 158 159 static int get_task_root(struct task_struct *task, struct path *root) 160 { 161 int result = -ENOENT; 162 163 task_lock(task); 164 if (task->fs) { 165 get_fs_root(task->fs, root); 166 result = 0; 167 } 168 task_unlock(task); 169 return result; 170 } 171 172 static int proc_cwd_link(struct dentry *dentry, struct path *path) 173 { 174 struct task_struct *task = get_proc_task(dentry->d_inode); 175 int result = -ENOENT; 176 177 if (task) { 178 task_lock(task); 179 if (task->fs) { 180 get_fs_pwd(task->fs, path); 181 result = 0; 182 } 183 task_unlock(task); 184 put_task_struct(task); 185 } 186 return result; 187 } 188 189 static int proc_root_link(struct dentry *dentry, struct path *path) 190 { 191 struct task_struct *task = get_proc_task(dentry->d_inode); 192 int result = -ENOENT; 193 194 if (task) { 195 result = get_task_root(task, path); 196 put_task_struct(task); 197 } 198 return result; 199 } 200 201 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 202 { 203 int res = 0; 204 unsigned int len; 205 struct mm_struct *mm = get_task_mm(task); 206 if (!mm) 207 goto out; 208 if (!mm->arg_end) 209 goto out_mm; /* Shh! No looking before we're done */ 210 211 len = mm->arg_end - mm->arg_start; 212 213 if (len > PAGE_SIZE) 214 len = PAGE_SIZE; 215 216 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 217 218 // If the nul at the end of args has been overwritten, then 219 // assume application is using setproctitle(3). 220 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 221 len = strnlen(buffer, res); 222 if (len < res) { 223 res = len; 224 } else { 225 len = mm->env_end - mm->env_start; 226 if (len > PAGE_SIZE - res) 227 len = PAGE_SIZE - res; 228 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 229 res = strnlen(buffer, res); 230 } 231 } 232 out_mm: 233 mmput(mm); 234 out: 235 return res; 236 } 237 238 static int proc_pid_auxv(struct task_struct *task, char *buffer) 239 { 240 struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ); 241 int res = PTR_ERR(mm); 242 if (mm && !IS_ERR(mm)) { 243 unsigned int nwords = 0; 244 do { 245 nwords += 2; 246 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 247 res = nwords * sizeof(mm->saved_auxv[0]); 248 if (res > PAGE_SIZE) 249 res = PAGE_SIZE; 250 memcpy(buffer, mm->saved_auxv, res); 251 mmput(mm); 252 } 253 return res; 254 } 255 256 257 #ifdef CONFIG_KALLSYMS 258 /* 259 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 260 * Returns the resolved symbol. If that fails, simply return the address. 261 */ 262 static int proc_pid_wchan(struct task_struct *task, char *buffer) 263 { 264 unsigned long wchan; 265 char symname[KSYM_NAME_LEN]; 266 267 wchan = get_wchan(task); 268 269 if (lookup_symbol_name(wchan, symname) < 0) 270 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 271 return 0; 272 else 273 return sprintf(buffer, "%lu", wchan); 274 else 275 return sprintf(buffer, "%s", symname); 276 } 277 #endif /* CONFIG_KALLSYMS */ 278 279 static int lock_trace(struct task_struct *task) 280 { 281 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 282 if (err) 283 return err; 284 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) { 285 mutex_unlock(&task->signal->cred_guard_mutex); 286 return -EPERM; 287 } 288 return 0; 289 } 290 291 static void unlock_trace(struct task_struct *task) 292 { 293 mutex_unlock(&task->signal->cred_guard_mutex); 294 } 295 296 #ifdef CONFIG_STACKTRACE 297 298 #define MAX_STACK_TRACE_DEPTH 64 299 300 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 301 struct pid *pid, struct task_struct *task) 302 { 303 struct stack_trace trace; 304 unsigned long *entries; 305 int err; 306 int i; 307 308 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 309 if (!entries) 310 return -ENOMEM; 311 312 trace.nr_entries = 0; 313 trace.max_entries = MAX_STACK_TRACE_DEPTH; 314 trace.entries = entries; 315 trace.skip = 0; 316 317 err = lock_trace(task); 318 if (!err) { 319 save_stack_trace_tsk(task, &trace); 320 321 for (i = 0; i < trace.nr_entries; i++) { 322 seq_printf(m, "[<%pK>] %pS\n", 323 (void *)entries[i], (void *)entries[i]); 324 } 325 unlock_trace(task); 326 } 327 kfree(entries); 328 329 return err; 330 } 331 #endif 332 333 #ifdef CONFIG_SCHEDSTATS 334 /* 335 * Provides /proc/PID/schedstat 336 */ 337 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 338 { 339 return sprintf(buffer, "%llu %llu %lu\n", 340 (unsigned long long)task->se.sum_exec_runtime, 341 (unsigned long long)task->sched_info.run_delay, 342 task->sched_info.pcount); 343 } 344 #endif 345 346 #ifdef CONFIG_LATENCYTOP 347 static int lstats_show_proc(struct seq_file *m, void *v) 348 { 349 int i; 350 struct inode *inode = m->private; 351 struct task_struct *task = get_proc_task(inode); 352 353 if (!task) 354 return -ESRCH; 355 seq_puts(m, "Latency Top version : v0.1\n"); 356 for (i = 0; i < 32; i++) { 357 struct latency_record *lr = &task->latency_record[i]; 358 if (lr->backtrace[0]) { 359 int q; 360 seq_printf(m, "%i %li %li", 361 lr->count, lr->time, lr->max); 362 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 363 unsigned long bt = lr->backtrace[q]; 364 if (!bt) 365 break; 366 if (bt == ULONG_MAX) 367 break; 368 seq_printf(m, " %ps", (void *)bt); 369 } 370 seq_putc(m, '\n'); 371 } 372 373 } 374 put_task_struct(task); 375 return 0; 376 } 377 378 static int lstats_open(struct inode *inode, struct file *file) 379 { 380 return single_open(file, lstats_show_proc, inode); 381 } 382 383 static ssize_t lstats_write(struct file *file, const char __user *buf, 384 size_t count, loff_t *offs) 385 { 386 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 387 388 if (!task) 389 return -ESRCH; 390 clear_all_latency_tracing(task); 391 put_task_struct(task); 392 393 return count; 394 } 395 396 static const struct file_operations proc_lstats_operations = { 397 .open = lstats_open, 398 .read = seq_read, 399 .write = lstats_write, 400 .llseek = seq_lseek, 401 .release = single_release, 402 }; 403 404 #endif 405 406 static int proc_oom_score(struct task_struct *task, char *buffer) 407 { 408 unsigned long totalpages = totalram_pages + total_swap_pages; 409 unsigned long points = 0; 410 411 read_lock(&tasklist_lock); 412 if (pid_alive(task)) 413 points = oom_badness(task, NULL, NULL, totalpages) * 414 1000 / totalpages; 415 read_unlock(&tasklist_lock); 416 return sprintf(buffer, "%lu\n", points); 417 } 418 419 struct limit_names { 420 char *name; 421 char *unit; 422 }; 423 424 static const struct limit_names lnames[RLIM_NLIMITS] = { 425 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 426 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 427 [RLIMIT_DATA] = {"Max data size", "bytes"}, 428 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 429 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 430 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 431 [RLIMIT_NPROC] = {"Max processes", "processes"}, 432 [RLIMIT_NOFILE] = {"Max open files", "files"}, 433 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 434 [RLIMIT_AS] = {"Max address space", "bytes"}, 435 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 436 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 437 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 438 [RLIMIT_NICE] = {"Max nice priority", NULL}, 439 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 440 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 441 }; 442 443 /* Display limits for a process */ 444 static int proc_pid_limits(struct task_struct *task, char *buffer) 445 { 446 unsigned int i; 447 int count = 0; 448 unsigned long flags; 449 char *bufptr = buffer; 450 451 struct rlimit rlim[RLIM_NLIMITS]; 452 453 if (!lock_task_sighand(task, &flags)) 454 return 0; 455 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 456 unlock_task_sighand(task, &flags); 457 458 /* 459 * print the file header 460 */ 461 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n", 462 "Limit", "Soft Limit", "Hard Limit", "Units"); 463 464 for (i = 0; i < RLIM_NLIMITS; i++) { 465 if (rlim[i].rlim_cur == RLIM_INFINITY) 466 count += sprintf(&bufptr[count], "%-25s %-20s ", 467 lnames[i].name, "unlimited"); 468 else 469 count += sprintf(&bufptr[count], "%-25s %-20lu ", 470 lnames[i].name, rlim[i].rlim_cur); 471 472 if (rlim[i].rlim_max == RLIM_INFINITY) 473 count += sprintf(&bufptr[count], "%-20s ", "unlimited"); 474 else 475 count += sprintf(&bufptr[count], "%-20lu ", 476 rlim[i].rlim_max); 477 478 if (lnames[i].unit) 479 count += sprintf(&bufptr[count], "%-10s\n", 480 lnames[i].unit); 481 else 482 count += sprintf(&bufptr[count], "\n"); 483 } 484 485 return count; 486 } 487 488 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 489 static int proc_pid_syscall(struct task_struct *task, char *buffer) 490 { 491 long nr; 492 unsigned long args[6], sp, pc; 493 int res = lock_trace(task); 494 if (res) 495 return res; 496 497 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 498 res = sprintf(buffer, "running\n"); 499 else if (nr < 0) 500 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 501 else 502 res = sprintf(buffer, 503 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 504 nr, 505 args[0], args[1], args[2], args[3], args[4], args[5], 506 sp, pc); 507 unlock_trace(task); 508 return res; 509 } 510 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 511 512 /************************************************************************/ 513 /* Here the fs part begins */ 514 /************************************************************************/ 515 516 /* permission checks */ 517 static int proc_fd_access_allowed(struct inode *inode) 518 { 519 struct task_struct *task; 520 int allowed = 0; 521 /* Allow access to a task's file descriptors if it is us or we 522 * may use ptrace attach to the process and find out that 523 * information. 524 */ 525 task = get_proc_task(inode); 526 if (task) { 527 allowed = ptrace_may_access(task, PTRACE_MODE_READ); 528 put_task_struct(task); 529 } 530 return allowed; 531 } 532 533 int proc_setattr(struct dentry *dentry, struct iattr *attr) 534 { 535 int error; 536 struct inode *inode = dentry->d_inode; 537 538 if (attr->ia_valid & ATTR_MODE) 539 return -EPERM; 540 541 error = inode_change_ok(inode, attr); 542 if (error) 543 return error; 544 545 if ((attr->ia_valid & ATTR_SIZE) && 546 attr->ia_size != i_size_read(inode)) { 547 error = vmtruncate(inode, attr->ia_size); 548 if (error) 549 return error; 550 } 551 552 setattr_copy(inode, attr); 553 mark_inode_dirty(inode); 554 return 0; 555 } 556 557 /* 558 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 559 * or euid/egid (for hide_pid_min=2)? 560 */ 561 static bool has_pid_permissions(struct pid_namespace *pid, 562 struct task_struct *task, 563 int hide_pid_min) 564 { 565 if (pid->hide_pid < hide_pid_min) 566 return true; 567 if (in_group_p(pid->pid_gid)) 568 return true; 569 return ptrace_may_access(task, PTRACE_MODE_READ); 570 } 571 572 573 static int proc_pid_permission(struct inode *inode, int mask) 574 { 575 struct pid_namespace *pid = inode->i_sb->s_fs_info; 576 struct task_struct *task; 577 bool has_perms; 578 579 task = get_proc_task(inode); 580 if (!task) 581 return -ESRCH; 582 has_perms = has_pid_permissions(pid, task, 1); 583 put_task_struct(task); 584 585 if (!has_perms) { 586 if (pid->hide_pid == 2) { 587 /* 588 * Let's make getdents(), stat(), and open() 589 * consistent with each other. If a process 590 * may not stat() a file, it shouldn't be seen 591 * in procfs at all. 592 */ 593 return -ENOENT; 594 } 595 596 return -EPERM; 597 } 598 return generic_permission(inode, mask); 599 } 600 601 602 603 static const struct inode_operations proc_def_inode_operations = { 604 .setattr = proc_setattr, 605 }; 606 607 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 608 609 static ssize_t proc_info_read(struct file * file, char __user * buf, 610 size_t count, loff_t *ppos) 611 { 612 struct inode * inode = file->f_path.dentry->d_inode; 613 unsigned long page; 614 ssize_t length; 615 struct task_struct *task = get_proc_task(inode); 616 617 length = -ESRCH; 618 if (!task) 619 goto out_no_task; 620 621 if (count > PROC_BLOCK_SIZE) 622 count = PROC_BLOCK_SIZE; 623 624 length = -ENOMEM; 625 if (!(page = __get_free_page(GFP_TEMPORARY))) 626 goto out; 627 628 length = PROC_I(inode)->op.proc_read(task, (char*)page); 629 630 if (length >= 0) 631 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 632 free_page(page); 633 out: 634 put_task_struct(task); 635 out_no_task: 636 return length; 637 } 638 639 static const struct file_operations proc_info_file_operations = { 640 .read = proc_info_read, 641 .llseek = generic_file_llseek, 642 }; 643 644 static int proc_single_show(struct seq_file *m, void *v) 645 { 646 struct inode *inode = m->private; 647 struct pid_namespace *ns; 648 struct pid *pid; 649 struct task_struct *task; 650 int ret; 651 652 ns = inode->i_sb->s_fs_info; 653 pid = proc_pid(inode); 654 task = get_pid_task(pid, PIDTYPE_PID); 655 if (!task) 656 return -ESRCH; 657 658 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 659 660 put_task_struct(task); 661 return ret; 662 } 663 664 static int proc_single_open(struct inode *inode, struct file *filp) 665 { 666 return single_open(filp, proc_single_show, inode); 667 } 668 669 static const struct file_operations proc_single_file_operations = { 670 .open = proc_single_open, 671 .read = seq_read, 672 .llseek = seq_lseek, 673 .release = single_release, 674 }; 675 676 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 677 { 678 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 679 struct mm_struct *mm; 680 681 if (!task) 682 return -ESRCH; 683 684 mm = mm_access(task, mode); 685 put_task_struct(task); 686 687 if (IS_ERR(mm)) 688 return PTR_ERR(mm); 689 690 if (mm) { 691 /* ensure this mm_struct can't be freed */ 692 atomic_inc(&mm->mm_count); 693 /* but do not pin its memory */ 694 mmput(mm); 695 } 696 697 file->private_data = mm; 698 699 return 0; 700 } 701 702 static int mem_open(struct inode *inode, struct file *file) 703 { 704 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 705 706 /* OK to pass negative loff_t, we can catch out-of-range */ 707 file->f_mode |= FMODE_UNSIGNED_OFFSET; 708 709 return ret; 710 } 711 712 static ssize_t mem_rw(struct file *file, char __user *buf, 713 size_t count, loff_t *ppos, int write) 714 { 715 struct mm_struct *mm = file->private_data; 716 unsigned long addr = *ppos; 717 ssize_t copied; 718 char *page; 719 720 if (!mm) 721 return 0; 722 723 page = (char *)__get_free_page(GFP_TEMPORARY); 724 if (!page) 725 return -ENOMEM; 726 727 copied = 0; 728 if (!atomic_inc_not_zero(&mm->mm_users)) 729 goto free; 730 731 while (count > 0) { 732 int this_len = min_t(int, count, PAGE_SIZE); 733 734 if (write && copy_from_user(page, buf, this_len)) { 735 copied = -EFAULT; 736 break; 737 } 738 739 this_len = access_remote_vm(mm, addr, page, this_len, write); 740 if (!this_len) { 741 if (!copied) 742 copied = -EIO; 743 break; 744 } 745 746 if (!write && copy_to_user(buf, page, this_len)) { 747 copied = -EFAULT; 748 break; 749 } 750 751 buf += this_len; 752 addr += this_len; 753 copied += this_len; 754 count -= this_len; 755 } 756 *ppos = addr; 757 758 mmput(mm); 759 free: 760 free_page((unsigned long) page); 761 return copied; 762 } 763 764 static ssize_t mem_read(struct file *file, char __user *buf, 765 size_t count, loff_t *ppos) 766 { 767 return mem_rw(file, buf, count, ppos, 0); 768 } 769 770 static ssize_t mem_write(struct file *file, const char __user *buf, 771 size_t count, loff_t *ppos) 772 { 773 return mem_rw(file, (char __user*)buf, count, ppos, 1); 774 } 775 776 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 777 { 778 switch (orig) { 779 case 0: 780 file->f_pos = offset; 781 break; 782 case 1: 783 file->f_pos += offset; 784 break; 785 default: 786 return -EINVAL; 787 } 788 force_successful_syscall_return(); 789 return file->f_pos; 790 } 791 792 static int mem_release(struct inode *inode, struct file *file) 793 { 794 struct mm_struct *mm = file->private_data; 795 if (mm) 796 mmdrop(mm); 797 return 0; 798 } 799 800 static const struct file_operations proc_mem_operations = { 801 .llseek = mem_lseek, 802 .read = mem_read, 803 .write = mem_write, 804 .open = mem_open, 805 .release = mem_release, 806 }; 807 808 static int environ_open(struct inode *inode, struct file *file) 809 { 810 return __mem_open(inode, file, PTRACE_MODE_READ); 811 } 812 813 static ssize_t environ_read(struct file *file, char __user *buf, 814 size_t count, loff_t *ppos) 815 { 816 char *page; 817 unsigned long src = *ppos; 818 int ret = 0; 819 struct mm_struct *mm = file->private_data; 820 821 if (!mm) 822 return 0; 823 824 page = (char *)__get_free_page(GFP_TEMPORARY); 825 if (!page) 826 return -ENOMEM; 827 828 ret = 0; 829 if (!atomic_inc_not_zero(&mm->mm_users)) 830 goto free; 831 while (count > 0) { 832 size_t this_len, max_len; 833 int retval; 834 835 if (src >= (mm->env_end - mm->env_start)) 836 break; 837 838 this_len = mm->env_end - (mm->env_start + src); 839 840 max_len = min_t(size_t, PAGE_SIZE, count); 841 this_len = min(max_len, this_len); 842 843 retval = access_remote_vm(mm, (mm->env_start + src), 844 page, this_len, 0); 845 846 if (retval <= 0) { 847 ret = retval; 848 break; 849 } 850 851 if (copy_to_user(buf, page, retval)) { 852 ret = -EFAULT; 853 break; 854 } 855 856 ret += retval; 857 src += retval; 858 buf += retval; 859 count -= retval; 860 } 861 *ppos = src; 862 mmput(mm); 863 864 free: 865 free_page((unsigned long) page); 866 return ret; 867 } 868 869 static const struct file_operations proc_environ_operations = { 870 .open = environ_open, 871 .read = environ_read, 872 .llseek = generic_file_llseek, 873 .release = mem_release, 874 }; 875 876 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 877 size_t count, loff_t *ppos) 878 { 879 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 880 char buffer[PROC_NUMBUF]; 881 int oom_score_adj = OOM_SCORE_ADJ_MIN; 882 unsigned long flags; 883 size_t len; 884 885 if (!task) 886 return -ESRCH; 887 if (lock_task_sighand(task, &flags)) { 888 oom_score_adj = task->signal->oom_score_adj; 889 unlock_task_sighand(task, &flags); 890 } 891 put_task_struct(task); 892 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj); 893 return simple_read_from_buffer(buf, count, ppos, buffer, len); 894 } 895 896 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 897 size_t count, loff_t *ppos) 898 { 899 struct task_struct *task; 900 char buffer[PROC_NUMBUF]; 901 unsigned long flags; 902 int oom_score_adj; 903 int err; 904 905 memset(buffer, 0, sizeof(buffer)); 906 if (count > sizeof(buffer) - 1) 907 count = sizeof(buffer) - 1; 908 if (copy_from_user(buffer, buf, count)) { 909 err = -EFAULT; 910 goto out; 911 } 912 913 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 914 if (err) 915 goto out; 916 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 917 oom_score_adj > OOM_SCORE_ADJ_MAX) { 918 err = -EINVAL; 919 goto out; 920 } 921 922 task = get_proc_task(file->f_path.dentry->d_inode); 923 if (!task) { 924 err = -ESRCH; 925 goto out; 926 } 927 928 task_lock(task); 929 if (!task->mm) { 930 err = -EINVAL; 931 goto err_task_lock; 932 } 933 934 if (!lock_task_sighand(task, &flags)) { 935 err = -ESRCH; 936 goto err_task_lock; 937 } 938 939 if (oom_score_adj < task->signal->oom_score_adj_min && 940 !capable(CAP_SYS_RESOURCE)) { 941 err = -EACCES; 942 goto err_sighand; 943 } 944 945 task->signal->oom_score_adj = oom_score_adj; 946 if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) 947 task->signal->oom_score_adj_min = oom_score_adj; 948 trace_oom_score_adj_update(task); 949 950 err_sighand: 951 unlock_task_sighand(task, &flags); 952 err_task_lock: 953 task_unlock(task); 954 put_task_struct(task); 955 out: 956 return err < 0 ? err : count; 957 } 958 959 static const struct file_operations proc_oom_score_adj_operations = { 960 .read = oom_score_adj_read, 961 .write = oom_score_adj_write, 962 .llseek = default_llseek, 963 }; 964 965 #ifdef CONFIG_AUDITSYSCALL 966 #define TMPBUFLEN 21 967 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 968 size_t count, loff_t *ppos) 969 { 970 struct inode * inode = file->f_path.dentry->d_inode; 971 struct task_struct *task = get_proc_task(inode); 972 ssize_t length; 973 char tmpbuf[TMPBUFLEN]; 974 975 if (!task) 976 return -ESRCH; 977 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 978 from_kuid(file->f_cred->user_ns, 979 audit_get_loginuid(task))); 980 put_task_struct(task); 981 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 982 } 983 984 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 985 size_t count, loff_t *ppos) 986 { 987 struct inode * inode = file->f_path.dentry->d_inode; 988 char *page, *tmp; 989 ssize_t length; 990 uid_t loginuid; 991 kuid_t kloginuid; 992 993 rcu_read_lock(); 994 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 995 rcu_read_unlock(); 996 return -EPERM; 997 } 998 rcu_read_unlock(); 999 1000 if (count >= PAGE_SIZE) 1001 count = PAGE_SIZE - 1; 1002 1003 if (*ppos != 0) { 1004 /* No partial writes. */ 1005 return -EINVAL; 1006 } 1007 page = (char*)__get_free_page(GFP_TEMPORARY); 1008 if (!page) 1009 return -ENOMEM; 1010 length = -EFAULT; 1011 if (copy_from_user(page, buf, count)) 1012 goto out_free_page; 1013 1014 page[count] = '\0'; 1015 loginuid = simple_strtoul(page, &tmp, 10); 1016 if (tmp == page) { 1017 length = -EINVAL; 1018 goto out_free_page; 1019 1020 } 1021 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1022 if (!uid_valid(kloginuid)) { 1023 length = -EINVAL; 1024 goto out_free_page; 1025 } 1026 1027 length = audit_set_loginuid(kloginuid); 1028 if (likely(length == 0)) 1029 length = count; 1030 1031 out_free_page: 1032 free_page((unsigned long) page); 1033 return length; 1034 } 1035 1036 static const struct file_operations proc_loginuid_operations = { 1037 .read = proc_loginuid_read, 1038 .write = proc_loginuid_write, 1039 .llseek = generic_file_llseek, 1040 }; 1041 1042 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1043 size_t count, loff_t *ppos) 1044 { 1045 struct inode * inode = file->f_path.dentry->d_inode; 1046 struct task_struct *task = get_proc_task(inode); 1047 ssize_t length; 1048 char tmpbuf[TMPBUFLEN]; 1049 1050 if (!task) 1051 return -ESRCH; 1052 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1053 audit_get_sessionid(task)); 1054 put_task_struct(task); 1055 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1056 } 1057 1058 static const struct file_operations proc_sessionid_operations = { 1059 .read = proc_sessionid_read, 1060 .llseek = generic_file_llseek, 1061 }; 1062 #endif 1063 1064 #ifdef CONFIG_FAULT_INJECTION 1065 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1066 size_t count, loff_t *ppos) 1067 { 1068 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 1069 char buffer[PROC_NUMBUF]; 1070 size_t len; 1071 int make_it_fail; 1072 1073 if (!task) 1074 return -ESRCH; 1075 make_it_fail = task->make_it_fail; 1076 put_task_struct(task); 1077 1078 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1079 1080 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1081 } 1082 1083 static ssize_t proc_fault_inject_write(struct file * file, 1084 const char __user * buf, size_t count, loff_t *ppos) 1085 { 1086 struct task_struct *task; 1087 char buffer[PROC_NUMBUF], *end; 1088 int make_it_fail; 1089 1090 if (!capable(CAP_SYS_RESOURCE)) 1091 return -EPERM; 1092 memset(buffer, 0, sizeof(buffer)); 1093 if (count > sizeof(buffer) - 1) 1094 count = sizeof(buffer) - 1; 1095 if (copy_from_user(buffer, buf, count)) 1096 return -EFAULT; 1097 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1098 if (*end) 1099 return -EINVAL; 1100 task = get_proc_task(file->f_dentry->d_inode); 1101 if (!task) 1102 return -ESRCH; 1103 task->make_it_fail = make_it_fail; 1104 put_task_struct(task); 1105 1106 return count; 1107 } 1108 1109 static const struct file_operations proc_fault_inject_operations = { 1110 .read = proc_fault_inject_read, 1111 .write = proc_fault_inject_write, 1112 .llseek = generic_file_llseek, 1113 }; 1114 #endif 1115 1116 1117 #ifdef CONFIG_SCHED_DEBUG 1118 /* 1119 * Print out various scheduling related per-task fields: 1120 */ 1121 static int sched_show(struct seq_file *m, void *v) 1122 { 1123 struct inode *inode = m->private; 1124 struct task_struct *p; 1125 1126 p = get_proc_task(inode); 1127 if (!p) 1128 return -ESRCH; 1129 proc_sched_show_task(p, m); 1130 1131 put_task_struct(p); 1132 1133 return 0; 1134 } 1135 1136 static ssize_t 1137 sched_write(struct file *file, const char __user *buf, 1138 size_t count, loff_t *offset) 1139 { 1140 struct inode *inode = file->f_path.dentry->d_inode; 1141 struct task_struct *p; 1142 1143 p = get_proc_task(inode); 1144 if (!p) 1145 return -ESRCH; 1146 proc_sched_set_task(p); 1147 1148 put_task_struct(p); 1149 1150 return count; 1151 } 1152 1153 static int sched_open(struct inode *inode, struct file *filp) 1154 { 1155 return single_open(filp, sched_show, inode); 1156 } 1157 1158 static const struct file_operations proc_pid_sched_operations = { 1159 .open = sched_open, 1160 .read = seq_read, 1161 .write = sched_write, 1162 .llseek = seq_lseek, 1163 .release = single_release, 1164 }; 1165 1166 #endif 1167 1168 #ifdef CONFIG_SCHED_AUTOGROUP 1169 /* 1170 * Print out autogroup related information: 1171 */ 1172 static int sched_autogroup_show(struct seq_file *m, void *v) 1173 { 1174 struct inode *inode = m->private; 1175 struct task_struct *p; 1176 1177 p = get_proc_task(inode); 1178 if (!p) 1179 return -ESRCH; 1180 proc_sched_autogroup_show_task(p, m); 1181 1182 put_task_struct(p); 1183 1184 return 0; 1185 } 1186 1187 static ssize_t 1188 sched_autogroup_write(struct file *file, const char __user *buf, 1189 size_t count, loff_t *offset) 1190 { 1191 struct inode *inode = file->f_path.dentry->d_inode; 1192 struct task_struct *p; 1193 char buffer[PROC_NUMBUF]; 1194 int nice; 1195 int err; 1196 1197 memset(buffer, 0, sizeof(buffer)); 1198 if (count > sizeof(buffer) - 1) 1199 count = sizeof(buffer) - 1; 1200 if (copy_from_user(buffer, buf, count)) 1201 return -EFAULT; 1202 1203 err = kstrtoint(strstrip(buffer), 0, &nice); 1204 if (err < 0) 1205 return err; 1206 1207 p = get_proc_task(inode); 1208 if (!p) 1209 return -ESRCH; 1210 1211 err = proc_sched_autogroup_set_nice(p, nice); 1212 if (err) 1213 count = err; 1214 1215 put_task_struct(p); 1216 1217 return count; 1218 } 1219 1220 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1221 { 1222 int ret; 1223 1224 ret = single_open(filp, sched_autogroup_show, NULL); 1225 if (!ret) { 1226 struct seq_file *m = filp->private_data; 1227 1228 m->private = inode; 1229 } 1230 return ret; 1231 } 1232 1233 static const struct file_operations proc_pid_sched_autogroup_operations = { 1234 .open = sched_autogroup_open, 1235 .read = seq_read, 1236 .write = sched_autogroup_write, 1237 .llseek = seq_lseek, 1238 .release = single_release, 1239 }; 1240 1241 #endif /* CONFIG_SCHED_AUTOGROUP */ 1242 1243 static ssize_t comm_write(struct file *file, const char __user *buf, 1244 size_t count, loff_t *offset) 1245 { 1246 struct inode *inode = file->f_path.dentry->d_inode; 1247 struct task_struct *p; 1248 char buffer[TASK_COMM_LEN]; 1249 1250 memset(buffer, 0, sizeof(buffer)); 1251 if (count > sizeof(buffer) - 1) 1252 count = sizeof(buffer) - 1; 1253 if (copy_from_user(buffer, buf, count)) 1254 return -EFAULT; 1255 1256 p = get_proc_task(inode); 1257 if (!p) 1258 return -ESRCH; 1259 1260 if (same_thread_group(current, p)) 1261 set_task_comm(p, buffer); 1262 else 1263 count = -EINVAL; 1264 1265 put_task_struct(p); 1266 1267 return count; 1268 } 1269 1270 static int comm_show(struct seq_file *m, void *v) 1271 { 1272 struct inode *inode = m->private; 1273 struct task_struct *p; 1274 1275 p = get_proc_task(inode); 1276 if (!p) 1277 return -ESRCH; 1278 1279 task_lock(p); 1280 seq_printf(m, "%s\n", p->comm); 1281 task_unlock(p); 1282 1283 put_task_struct(p); 1284 1285 return 0; 1286 } 1287 1288 static int comm_open(struct inode *inode, struct file *filp) 1289 { 1290 return single_open(filp, comm_show, inode); 1291 } 1292 1293 static const struct file_operations proc_pid_set_comm_operations = { 1294 .open = comm_open, 1295 .read = seq_read, 1296 .write = comm_write, 1297 .llseek = seq_lseek, 1298 .release = single_release, 1299 }; 1300 1301 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1302 { 1303 struct task_struct *task; 1304 struct mm_struct *mm; 1305 struct file *exe_file; 1306 1307 task = get_proc_task(dentry->d_inode); 1308 if (!task) 1309 return -ENOENT; 1310 mm = get_task_mm(task); 1311 put_task_struct(task); 1312 if (!mm) 1313 return -ENOENT; 1314 exe_file = get_mm_exe_file(mm); 1315 mmput(mm); 1316 if (exe_file) { 1317 *exe_path = exe_file->f_path; 1318 path_get(&exe_file->f_path); 1319 fput(exe_file); 1320 return 0; 1321 } else 1322 return -ENOENT; 1323 } 1324 1325 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1326 { 1327 struct inode *inode = dentry->d_inode; 1328 struct path path; 1329 int error = -EACCES; 1330 1331 /* Are we allowed to snoop on the tasks file descriptors? */ 1332 if (!proc_fd_access_allowed(inode)) 1333 goto out; 1334 1335 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1336 if (error) 1337 goto out; 1338 1339 nd_jump_link(nd, &path); 1340 return NULL; 1341 out: 1342 return ERR_PTR(error); 1343 } 1344 1345 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1346 { 1347 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1348 char *pathname; 1349 int len; 1350 1351 if (!tmp) 1352 return -ENOMEM; 1353 1354 pathname = d_path(path, tmp, PAGE_SIZE); 1355 len = PTR_ERR(pathname); 1356 if (IS_ERR(pathname)) 1357 goto out; 1358 len = tmp + PAGE_SIZE - 1 - pathname; 1359 1360 if (len > buflen) 1361 len = buflen; 1362 if (copy_to_user(buffer, pathname, len)) 1363 len = -EFAULT; 1364 out: 1365 free_page((unsigned long)tmp); 1366 return len; 1367 } 1368 1369 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1370 { 1371 int error = -EACCES; 1372 struct inode *inode = dentry->d_inode; 1373 struct path path; 1374 1375 /* Are we allowed to snoop on the tasks file descriptors? */ 1376 if (!proc_fd_access_allowed(inode)) 1377 goto out; 1378 1379 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1380 if (error) 1381 goto out; 1382 1383 error = do_proc_readlink(&path, buffer, buflen); 1384 path_put(&path); 1385 out: 1386 return error; 1387 } 1388 1389 const struct inode_operations proc_pid_link_inode_operations = { 1390 .readlink = proc_pid_readlink, 1391 .follow_link = proc_pid_follow_link, 1392 .setattr = proc_setattr, 1393 }; 1394 1395 1396 /* building an inode */ 1397 1398 struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1399 { 1400 struct inode * inode; 1401 struct proc_inode *ei; 1402 const struct cred *cred; 1403 1404 /* We need a new inode */ 1405 1406 inode = new_inode(sb); 1407 if (!inode) 1408 goto out; 1409 1410 /* Common stuff */ 1411 ei = PROC_I(inode); 1412 inode->i_ino = get_next_ino(); 1413 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1414 inode->i_op = &proc_def_inode_operations; 1415 1416 /* 1417 * grab the reference to task. 1418 */ 1419 ei->pid = get_task_pid(task, PIDTYPE_PID); 1420 if (!ei->pid) 1421 goto out_unlock; 1422 1423 if (task_dumpable(task)) { 1424 rcu_read_lock(); 1425 cred = __task_cred(task); 1426 inode->i_uid = cred->euid; 1427 inode->i_gid = cred->egid; 1428 rcu_read_unlock(); 1429 } 1430 security_task_to_inode(task, inode); 1431 1432 out: 1433 return inode; 1434 1435 out_unlock: 1436 iput(inode); 1437 return NULL; 1438 } 1439 1440 int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1441 { 1442 struct inode *inode = dentry->d_inode; 1443 struct task_struct *task; 1444 const struct cred *cred; 1445 struct pid_namespace *pid = dentry->d_sb->s_fs_info; 1446 1447 generic_fillattr(inode, stat); 1448 1449 rcu_read_lock(); 1450 stat->uid = GLOBAL_ROOT_UID; 1451 stat->gid = GLOBAL_ROOT_GID; 1452 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1453 if (task) { 1454 if (!has_pid_permissions(pid, task, 2)) { 1455 rcu_read_unlock(); 1456 /* 1457 * This doesn't prevent learning whether PID exists, 1458 * it only makes getattr() consistent with readdir(). 1459 */ 1460 return -ENOENT; 1461 } 1462 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1463 task_dumpable(task)) { 1464 cred = __task_cred(task); 1465 stat->uid = cred->euid; 1466 stat->gid = cred->egid; 1467 } 1468 } 1469 rcu_read_unlock(); 1470 return 0; 1471 } 1472 1473 /* dentry stuff */ 1474 1475 /* 1476 * Exceptional case: normally we are not allowed to unhash a busy 1477 * directory. In this case, however, we can do it - no aliasing problems 1478 * due to the way we treat inodes. 1479 * 1480 * Rewrite the inode's ownerships here because the owning task may have 1481 * performed a setuid(), etc. 1482 * 1483 * Before the /proc/pid/status file was created the only way to read 1484 * the effective uid of a /process was to stat /proc/pid. Reading 1485 * /proc/pid/status is slow enough that procps and other packages 1486 * kept stating /proc/pid. To keep the rules in /proc simple I have 1487 * made this apply to all per process world readable and executable 1488 * directories. 1489 */ 1490 int pid_revalidate(struct dentry *dentry, unsigned int flags) 1491 { 1492 struct inode *inode; 1493 struct task_struct *task; 1494 const struct cred *cred; 1495 1496 if (flags & LOOKUP_RCU) 1497 return -ECHILD; 1498 1499 inode = dentry->d_inode; 1500 task = get_proc_task(inode); 1501 1502 if (task) { 1503 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1504 task_dumpable(task)) { 1505 rcu_read_lock(); 1506 cred = __task_cred(task); 1507 inode->i_uid = cred->euid; 1508 inode->i_gid = cred->egid; 1509 rcu_read_unlock(); 1510 } else { 1511 inode->i_uid = GLOBAL_ROOT_UID; 1512 inode->i_gid = GLOBAL_ROOT_GID; 1513 } 1514 inode->i_mode &= ~(S_ISUID | S_ISGID); 1515 security_task_to_inode(task, inode); 1516 put_task_struct(task); 1517 return 1; 1518 } 1519 d_drop(dentry); 1520 return 0; 1521 } 1522 1523 const struct dentry_operations pid_dentry_operations = 1524 { 1525 .d_revalidate = pid_revalidate, 1526 .d_delete = pid_delete_dentry, 1527 }; 1528 1529 /* Lookups */ 1530 1531 /* 1532 * Fill a directory entry. 1533 * 1534 * If possible create the dcache entry and derive our inode number and 1535 * file type from dcache entry. 1536 * 1537 * Since all of the proc inode numbers are dynamically generated, the inode 1538 * numbers do not exist until the inode is cache. This means creating the 1539 * the dcache entry in readdir is necessary to keep the inode numbers 1540 * reported by readdir in sync with the inode numbers reported 1541 * by stat. 1542 */ 1543 int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 1544 const char *name, int len, 1545 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1546 { 1547 struct dentry *child, *dir = filp->f_path.dentry; 1548 struct inode *inode; 1549 struct qstr qname; 1550 ino_t ino = 0; 1551 unsigned type = DT_UNKNOWN; 1552 1553 qname.name = name; 1554 qname.len = len; 1555 qname.hash = full_name_hash(name, len); 1556 1557 child = d_lookup(dir, &qname); 1558 if (!child) { 1559 struct dentry *new; 1560 new = d_alloc(dir, &qname); 1561 if (new) { 1562 child = instantiate(dir->d_inode, new, task, ptr); 1563 if (child) 1564 dput(new); 1565 else 1566 child = new; 1567 } 1568 } 1569 if (!child || IS_ERR(child) || !child->d_inode) 1570 goto end_instantiate; 1571 inode = child->d_inode; 1572 if (inode) { 1573 ino = inode->i_ino; 1574 type = inode->i_mode >> 12; 1575 } 1576 dput(child); 1577 end_instantiate: 1578 if (!ino) 1579 ino = find_inode_number(dir, &qname); 1580 if (!ino) 1581 ino = 1; 1582 return filldir(dirent, name, len, filp->f_pos, ino, type); 1583 } 1584 1585 #ifdef CONFIG_CHECKPOINT_RESTORE 1586 1587 /* 1588 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1589 * which represent vma start and end addresses. 1590 */ 1591 static int dname_to_vma_addr(struct dentry *dentry, 1592 unsigned long *start, unsigned long *end) 1593 { 1594 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) 1595 return -EINVAL; 1596 1597 return 0; 1598 } 1599 1600 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1601 { 1602 unsigned long vm_start, vm_end; 1603 bool exact_vma_exists = false; 1604 struct mm_struct *mm = NULL; 1605 struct task_struct *task; 1606 const struct cred *cred; 1607 struct inode *inode; 1608 int status = 0; 1609 1610 if (flags & LOOKUP_RCU) 1611 return -ECHILD; 1612 1613 if (!capable(CAP_SYS_ADMIN)) { 1614 status = -EACCES; 1615 goto out_notask; 1616 } 1617 1618 inode = dentry->d_inode; 1619 task = get_proc_task(inode); 1620 if (!task) 1621 goto out_notask; 1622 1623 mm = mm_access(task, PTRACE_MODE_READ); 1624 if (IS_ERR_OR_NULL(mm)) 1625 goto out; 1626 1627 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1628 down_read(&mm->mmap_sem); 1629 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1630 up_read(&mm->mmap_sem); 1631 } 1632 1633 mmput(mm); 1634 1635 if (exact_vma_exists) { 1636 if (task_dumpable(task)) { 1637 rcu_read_lock(); 1638 cred = __task_cred(task); 1639 inode->i_uid = cred->euid; 1640 inode->i_gid = cred->egid; 1641 rcu_read_unlock(); 1642 } else { 1643 inode->i_uid = GLOBAL_ROOT_UID; 1644 inode->i_gid = GLOBAL_ROOT_GID; 1645 } 1646 security_task_to_inode(task, inode); 1647 status = 1; 1648 } 1649 1650 out: 1651 put_task_struct(task); 1652 1653 out_notask: 1654 if (status <= 0) 1655 d_drop(dentry); 1656 1657 return status; 1658 } 1659 1660 static const struct dentry_operations tid_map_files_dentry_operations = { 1661 .d_revalidate = map_files_d_revalidate, 1662 .d_delete = pid_delete_dentry, 1663 }; 1664 1665 static int proc_map_files_get_link(struct dentry *dentry, struct path *path) 1666 { 1667 unsigned long vm_start, vm_end; 1668 struct vm_area_struct *vma; 1669 struct task_struct *task; 1670 struct mm_struct *mm; 1671 int rc; 1672 1673 rc = -ENOENT; 1674 task = get_proc_task(dentry->d_inode); 1675 if (!task) 1676 goto out; 1677 1678 mm = get_task_mm(task); 1679 put_task_struct(task); 1680 if (!mm) 1681 goto out; 1682 1683 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1684 if (rc) 1685 goto out_mmput; 1686 1687 down_read(&mm->mmap_sem); 1688 vma = find_exact_vma(mm, vm_start, vm_end); 1689 if (vma && vma->vm_file) { 1690 *path = vma->vm_file->f_path; 1691 path_get(path); 1692 rc = 0; 1693 } 1694 up_read(&mm->mmap_sem); 1695 1696 out_mmput: 1697 mmput(mm); 1698 out: 1699 return rc; 1700 } 1701 1702 struct map_files_info { 1703 fmode_t mode; 1704 unsigned long len; 1705 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ 1706 }; 1707 1708 static struct dentry * 1709 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, 1710 struct task_struct *task, const void *ptr) 1711 { 1712 fmode_t mode = (fmode_t)(unsigned long)ptr; 1713 struct proc_inode *ei; 1714 struct inode *inode; 1715 1716 inode = proc_pid_make_inode(dir->i_sb, task); 1717 if (!inode) 1718 return ERR_PTR(-ENOENT); 1719 1720 ei = PROC_I(inode); 1721 ei->op.proc_get_link = proc_map_files_get_link; 1722 1723 inode->i_op = &proc_pid_link_inode_operations; 1724 inode->i_size = 64; 1725 inode->i_mode = S_IFLNK; 1726 1727 if (mode & FMODE_READ) 1728 inode->i_mode |= S_IRUSR; 1729 if (mode & FMODE_WRITE) 1730 inode->i_mode |= S_IWUSR; 1731 1732 d_set_d_op(dentry, &tid_map_files_dentry_operations); 1733 d_add(dentry, inode); 1734 1735 return NULL; 1736 } 1737 1738 static struct dentry *proc_map_files_lookup(struct inode *dir, 1739 struct dentry *dentry, unsigned int flags) 1740 { 1741 unsigned long vm_start, vm_end; 1742 struct vm_area_struct *vma; 1743 struct task_struct *task; 1744 struct dentry *result; 1745 struct mm_struct *mm; 1746 1747 result = ERR_PTR(-EACCES); 1748 if (!capable(CAP_SYS_ADMIN)) 1749 goto out; 1750 1751 result = ERR_PTR(-ENOENT); 1752 task = get_proc_task(dir); 1753 if (!task) 1754 goto out; 1755 1756 result = ERR_PTR(-EACCES); 1757 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 1758 goto out_put_task; 1759 1760 result = ERR_PTR(-ENOENT); 1761 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 1762 goto out_put_task; 1763 1764 mm = get_task_mm(task); 1765 if (!mm) 1766 goto out_put_task; 1767 1768 down_read(&mm->mmap_sem); 1769 vma = find_exact_vma(mm, vm_start, vm_end); 1770 if (!vma) 1771 goto out_no_vma; 1772 1773 result = proc_map_files_instantiate(dir, dentry, task, 1774 (void *)(unsigned long)vma->vm_file->f_mode); 1775 1776 out_no_vma: 1777 up_read(&mm->mmap_sem); 1778 mmput(mm); 1779 out_put_task: 1780 put_task_struct(task); 1781 out: 1782 return result; 1783 } 1784 1785 static const struct inode_operations proc_map_files_inode_operations = { 1786 .lookup = proc_map_files_lookup, 1787 .permission = proc_fd_permission, 1788 .setattr = proc_setattr, 1789 }; 1790 1791 static int 1792 proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir) 1793 { 1794 struct dentry *dentry = filp->f_path.dentry; 1795 struct inode *inode = dentry->d_inode; 1796 struct vm_area_struct *vma; 1797 struct task_struct *task; 1798 struct mm_struct *mm; 1799 ino_t ino; 1800 int ret; 1801 1802 ret = -EACCES; 1803 if (!capable(CAP_SYS_ADMIN)) 1804 goto out; 1805 1806 ret = -ENOENT; 1807 task = get_proc_task(inode); 1808 if (!task) 1809 goto out; 1810 1811 ret = -EACCES; 1812 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 1813 goto out_put_task; 1814 1815 ret = 0; 1816 switch (filp->f_pos) { 1817 case 0: 1818 ino = inode->i_ino; 1819 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0) 1820 goto out_put_task; 1821 filp->f_pos++; 1822 case 1: 1823 ino = parent_ino(dentry); 1824 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1825 goto out_put_task; 1826 filp->f_pos++; 1827 default: 1828 { 1829 unsigned long nr_files, pos, i; 1830 struct flex_array *fa = NULL; 1831 struct map_files_info info; 1832 struct map_files_info *p; 1833 1834 mm = get_task_mm(task); 1835 if (!mm) 1836 goto out_put_task; 1837 down_read(&mm->mmap_sem); 1838 1839 nr_files = 0; 1840 1841 /* 1842 * We need two passes here: 1843 * 1844 * 1) Collect vmas of mapped files with mmap_sem taken 1845 * 2) Release mmap_sem and instantiate entries 1846 * 1847 * otherwise we get lockdep complained, since filldir() 1848 * routine might require mmap_sem taken in might_fault(). 1849 */ 1850 1851 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 1852 if (vma->vm_file && ++pos > filp->f_pos) 1853 nr_files++; 1854 } 1855 1856 if (nr_files) { 1857 fa = flex_array_alloc(sizeof(info), nr_files, 1858 GFP_KERNEL); 1859 if (!fa || flex_array_prealloc(fa, 0, nr_files, 1860 GFP_KERNEL)) { 1861 ret = -ENOMEM; 1862 if (fa) 1863 flex_array_free(fa); 1864 up_read(&mm->mmap_sem); 1865 mmput(mm); 1866 goto out_put_task; 1867 } 1868 for (i = 0, vma = mm->mmap, pos = 2; vma; 1869 vma = vma->vm_next) { 1870 if (!vma->vm_file) 1871 continue; 1872 if (++pos <= filp->f_pos) 1873 continue; 1874 1875 info.mode = vma->vm_file->f_mode; 1876 info.len = snprintf(info.name, 1877 sizeof(info.name), "%lx-%lx", 1878 vma->vm_start, vma->vm_end); 1879 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 1880 BUG(); 1881 } 1882 } 1883 up_read(&mm->mmap_sem); 1884 1885 for (i = 0; i < nr_files; i++) { 1886 p = flex_array_get(fa, i); 1887 ret = proc_fill_cache(filp, dirent, filldir, 1888 p->name, p->len, 1889 proc_map_files_instantiate, 1890 task, 1891 (void *)(unsigned long)p->mode); 1892 if (ret) 1893 break; 1894 filp->f_pos++; 1895 } 1896 if (fa) 1897 flex_array_free(fa); 1898 mmput(mm); 1899 } 1900 } 1901 1902 out_put_task: 1903 put_task_struct(task); 1904 out: 1905 return ret; 1906 } 1907 1908 static const struct file_operations proc_map_files_operations = { 1909 .read = generic_read_dir, 1910 .readdir = proc_map_files_readdir, 1911 .llseek = default_llseek, 1912 }; 1913 1914 #endif /* CONFIG_CHECKPOINT_RESTORE */ 1915 1916 static struct dentry *proc_pident_instantiate(struct inode *dir, 1917 struct dentry *dentry, struct task_struct *task, const void *ptr) 1918 { 1919 const struct pid_entry *p = ptr; 1920 struct inode *inode; 1921 struct proc_inode *ei; 1922 struct dentry *error = ERR_PTR(-ENOENT); 1923 1924 inode = proc_pid_make_inode(dir->i_sb, task); 1925 if (!inode) 1926 goto out; 1927 1928 ei = PROC_I(inode); 1929 inode->i_mode = p->mode; 1930 if (S_ISDIR(inode->i_mode)) 1931 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 1932 if (p->iop) 1933 inode->i_op = p->iop; 1934 if (p->fop) 1935 inode->i_fop = p->fop; 1936 ei->op = p->op; 1937 d_set_d_op(dentry, &pid_dentry_operations); 1938 d_add(dentry, inode); 1939 /* Close the race of the process dying before we return the dentry */ 1940 if (pid_revalidate(dentry, 0)) 1941 error = NULL; 1942 out: 1943 return error; 1944 } 1945 1946 static struct dentry *proc_pident_lookup(struct inode *dir, 1947 struct dentry *dentry, 1948 const struct pid_entry *ents, 1949 unsigned int nents) 1950 { 1951 struct dentry *error; 1952 struct task_struct *task = get_proc_task(dir); 1953 const struct pid_entry *p, *last; 1954 1955 error = ERR_PTR(-ENOENT); 1956 1957 if (!task) 1958 goto out_no_task; 1959 1960 /* 1961 * Yes, it does not scale. And it should not. Don't add 1962 * new entries into /proc/<tgid>/ without very good reasons. 1963 */ 1964 last = &ents[nents - 1]; 1965 for (p = ents; p <= last; p++) { 1966 if (p->len != dentry->d_name.len) 1967 continue; 1968 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1969 break; 1970 } 1971 if (p > last) 1972 goto out; 1973 1974 error = proc_pident_instantiate(dir, dentry, task, p); 1975 out: 1976 put_task_struct(task); 1977 out_no_task: 1978 return error; 1979 } 1980 1981 static int proc_pident_fill_cache(struct file *filp, void *dirent, 1982 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 1983 { 1984 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 1985 proc_pident_instantiate, task, p); 1986 } 1987 1988 static int proc_pident_readdir(struct file *filp, 1989 void *dirent, filldir_t filldir, 1990 const struct pid_entry *ents, unsigned int nents) 1991 { 1992 int i; 1993 struct dentry *dentry = filp->f_path.dentry; 1994 struct inode *inode = dentry->d_inode; 1995 struct task_struct *task = get_proc_task(inode); 1996 const struct pid_entry *p, *last; 1997 ino_t ino; 1998 int ret; 1999 2000 ret = -ENOENT; 2001 if (!task) 2002 goto out_no_task; 2003 2004 ret = 0; 2005 i = filp->f_pos; 2006 switch (i) { 2007 case 0: 2008 ino = inode->i_ino; 2009 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 2010 goto out; 2011 i++; 2012 filp->f_pos++; 2013 /* fall through */ 2014 case 1: 2015 ino = parent_ino(dentry); 2016 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 2017 goto out; 2018 i++; 2019 filp->f_pos++; 2020 /* fall through */ 2021 default: 2022 i -= 2; 2023 if (i >= nents) { 2024 ret = 1; 2025 goto out; 2026 } 2027 p = ents + i; 2028 last = &ents[nents - 1]; 2029 while (p <= last) { 2030 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) 2031 goto out; 2032 filp->f_pos++; 2033 p++; 2034 } 2035 } 2036 2037 ret = 1; 2038 out: 2039 put_task_struct(task); 2040 out_no_task: 2041 return ret; 2042 } 2043 2044 #ifdef CONFIG_SECURITY 2045 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2046 size_t count, loff_t *ppos) 2047 { 2048 struct inode * inode = file->f_path.dentry->d_inode; 2049 char *p = NULL; 2050 ssize_t length; 2051 struct task_struct *task = get_proc_task(inode); 2052 2053 if (!task) 2054 return -ESRCH; 2055 2056 length = security_getprocattr(task, 2057 (char*)file->f_path.dentry->d_name.name, 2058 &p); 2059 put_task_struct(task); 2060 if (length > 0) 2061 length = simple_read_from_buffer(buf, count, ppos, p, length); 2062 kfree(p); 2063 return length; 2064 } 2065 2066 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2067 size_t count, loff_t *ppos) 2068 { 2069 struct inode * inode = file->f_path.dentry->d_inode; 2070 char *page; 2071 ssize_t length; 2072 struct task_struct *task = get_proc_task(inode); 2073 2074 length = -ESRCH; 2075 if (!task) 2076 goto out_no_task; 2077 if (count > PAGE_SIZE) 2078 count = PAGE_SIZE; 2079 2080 /* No partial writes. */ 2081 length = -EINVAL; 2082 if (*ppos != 0) 2083 goto out; 2084 2085 length = -ENOMEM; 2086 page = (char*)__get_free_page(GFP_TEMPORARY); 2087 if (!page) 2088 goto out; 2089 2090 length = -EFAULT; 2091 if (copy_from_user(page, buf, count)) 2092 goto out_free; 2093 2094 /* Guard against adverse ptrace interaction */ 2095 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex); 2096 if (length < 0) 2097 goto out_free; 2098 2099 length = security_setprocattr(task, 2100 (char*)file->f_path.dentry->d_name.name, 2101 (void*)page, count); 2102 mutex_unlock(&task->signal->cred_guard_mutex); 2103 out_free: 2104 free_page((unsigned long) page); 2105 out: 2106 put_task_struct(task); 2107 out_no_task: 2108 return length; 2109 } 2110 2111 static const struct file_operations proc_pid_attr_operations = { 2112 .read = proc_pid_attr_read, 2113 .write = proc_pid_attr_write, 2114 .llseek = generic_file_llseek, 2115 }; 2116 2117 static const struct pid_entry attr_dir_stuff[] = { 2118 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2119 REG("prev", S_IRUGO, proc_pid_attr_operations), 2120 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2121 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2122 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2123 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2124 }; 2125 2126 static int proc_attr_dir_readdir(struct file * filp, 2127 void * dirent, filldir_t filldir) 2128 { 2129 return proc_pident_readdir(filp,dirent,filldir, 2130 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); 2131 } 2132 2133 static const struct file_operations proc_attr_dir_operations = { 2134 .read = generic_read_dir, 2135 .readdir = proc_attr_dir_readdir, 2136 .llseek = default_llseek, 2137 }; 2138 2139 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2140 struct dentry *dentry, unsigned int flags) 2141 { 2142 return proc_pident_lookup(dir, dentry, 2143 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2144 } 2145 2146 static const struct inode_operations proc_attr_dir_inode_operations = { 2147 .lookup = proc_attr_dir_lookup, 2148 .getattr = pid_getattr, 2149 .setattr = proc_setattr, 2150 }; 2151 2152 #endif 2153 2154 #ifdef CONFIG_ELF_CORE 2155 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2156 size_t count, loff_t *ppos) 2157 { 2158 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 2159 struct mm_struct *mm; 2160 char buffer[PROC_NUMBUF]; 2161 size_t len; 2162 int ret; 2163 2164 if (!task) 2165 return -ESRCH; 2166 2167 ret = 0; 2168 mm = get_task_mm(task); 2169 if (mm) { 2170 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2171 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2172 MMF_DUMP_FILTER_SHIFT)); 2173 mmput(mm); 2174 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2175 } 2176 2177 put_task_struct(task); 2178 2179 return ret; 2180 } 2181 2182 static ssize_t proc_coredump_filter_write(struct file *file, 2183 const char __user *buf, 2184 size_t count, 2185 loff_t *ppos) 2186 { 2187 struct task_struct *task; 2188 struct mm_struct *mm; 2189 char buffer[PROC_NUMBUF], *end; 2190 unsigned int val; 2191 int ret; 2192 int i; 2193 unsigned long mask; 2194 2195 ret = -EFAULT; 2196 memset(buffer, 0, sizeof(buffer)); 2197 if (count > sizeof(buffer) - 1) 2198 count = sizeof(buffer) - 1; 2199 if (copy_from_user(buffer, buf, count)) 2200 goto out_no_task; 2201 2202 ret = -EINVAL; 2203 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2204 if (*end == '\n') 2205 end++; 2206 if (end - buffer == 0) 2207 goto out_no_task; 2208 2209 ret = -ESRCH; 2210 task = get_proc_task(file->f_dentry->d_inode); 2211 if (!task) 2212 goto out_no_task; 2213 2214 ret = end - buffer; 2215 mm = get_task_mm(task); 2216 if (!mm) 2217 goto out_no_mm; 2218 2219 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2220 if (val & mask) 2221 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2222 else 2223 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2224 } 2225 2226 mmput(mm); 2227 out_no_mm: 2228 put_task_struct(task); 2229 out_no_task: 2230 return ret; 2231 } 2232 2233 static const struct file_operations proc_coredump_filter_operations = { 2234 .read = proc_coredump_filter_read, 2235 .write = proc_coredump_filter_write, 2236 .llseek = generic_file_llseek, 2237 }; 2238 #endif 2239 2240 /* 2241 * /proc/self: 2242 */ 2243 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 2244 int buflen) 2245 { 2246 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2247 pid_t tgid = task_tgid_nr_ns(current, ns); 2248 char tmp[PROC_NUMBUF]; 2249 if (!tgid) 2250 return -ENOENT; 2251 sprintf(tmp, "%d", tgid); 2252 return vfs_readlink(dentry,buffer,buflen,tmp); 2253 } 2254 2255 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 2256 { 2257 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2258 pid_t tgid = task_tgid_nr_ns(current, ns); 2259 char *name = ERR_PTR(-ENOENT); 2260 if (tgid) { 2261 /* 11 for max length of signed int in decimal + NULL term */ 2262 name = kmalloc(12, GFP_KERNEL); 2263 if (!name) 2264 name = ERR_PTR(-ENOMEM); 2265 else 2266 sprintf(name, "%d", tgid); 2267 } 2268 nd_set_link(nd, name); 2269 return NULL; 2270 } 2271 2272 static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd, 2273 void *cookie) 2274 { 2275 char *s = nd_get_link(nd); 2276 if (!IS_ERR(s)) 2277 kfree(s); 2278 } 2279 2280 static const struct inode_operations proc_self_inode_operations = { 2281 .readlink = proc_self_readlink, 2282 .follow_link = proc_self_follow_link, 2283 .put_link = proc_self_put_link, 2284 }; 2285 2286 /* 2287 * proc base 2288 * 2289 * These are the directory entries in the root directory of /proc 2290 * that properly belong to the /proc filesystem, as they describe 2291 * describe something that is process related. 2292 */ 2293 static const struct pid_entry proc_base_stuff[] = { 2294 NOD("self", S_IFLNK|S_IRWXUGO, 2295 &proc_self_inode_operations, NULL, {}), 2296 }; 2297 2298 static struct dentry *proc_base_instantiate(struct inode *dir, 2299 struct dentry *dentry, struct task_struct *task, const void *ptr) 2300 { 2301 const struct pid_entry *p = ptr; 2302 struct inode *inode; 2303 struct proc_inode *ei; 2304 struct dentry *error; 2305 2306 /* Allocate the inode */ 2307 error = ERR_PTR(-ENOMEM); 2308 inode = new_inode(dir->i_sb); 2309 if (!inode) 2310 goto out; 2311 2312 /* Initialize the inode */ 2313 ei = PROC_I(inode); 2314 inode->i_ino = get_next_ino(); 2315 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2316 2317 /* 2318 * grab the reference to the task. 2319 */ 2320 ei->pid = get_task_pid(task, PIDTYPE_PID); 2321 if (!ei->pid) 2322 goto out_iput; 2323 2324 inode->i_mode = p->mode; 2325 if (S_ISDIR(inode->i_mode)) 2326 set_nlink(inode, 2); 2327 if (S_ISLNK(inode->i_mode)) 2328 inode->i_size = 64; 2329 if (p->iop) 2330 inode->i_op = p->iop; 2331 if (p->fop) 2332 inode->i_fop = p->fop; 2333 ei->op = p->op; 2334 d_add(dentry, inode); 2335 error = NULL; 2336 out: 2337 return error; 2338 out_iput: 2339 iput(inode); 2340 goto out; 2341 } 2342 2343 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 2344 { 2345 struct dentry *error; 2346 struct task_struct *task = get_proc_task(dir); 2347 const struct pid_entry *p, *last; 2348 2349 error = ERR_PTR(-ENOENT); 2350 2351 if (!task) 2352 goto out_no_task; 2353 2354 /* Lookup the directory entry */ 2355 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; 2356 for (p = proc_base_stuff; p <= last; p++) { 2357 if (p->len != dentry->d_name.len) 2358 continue; 2359 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2360 break; 2361 } 2362 if (p > last) 2363 goto out; 2364 2365 error = proc_base_instantiate(dir, dentry, task, p); 2366 2367 out: 2368 put_task_struct(task); 2369 out_no_task: 2370 return error; 2371 } 2372 2373 static int proc_base_fill_cache(struct file *filp, void *dirent, 2374 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2375 { 2376 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2377 proc_base_instantiate, task, p); 2378 } 2379 2380 #ifdef CONFIG_TASK_IO_ACCOUNTING 2381 static int do_io_accounting(struct task_struct *task, char *buffer, int whole) 2382 { 2383 struct task_io_accounting acct = task->ioac; 2384 unsigned long flags; 2385 int result; 2386 2387 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2388 if (result) 2389 return result; 2390 2391 if (!ptrace_may_access(task, PTRACE_MODE_READ)) { 2392 result = -EACCES; 2393 goto out_unlock; 2394 } 2395 2396 if (whole && lock_task_sighand(task, &flags)) { 2397 struct task_struct *t = task; 2398 2399 task_io_accounting_add(&acct, &task->signal->ioac); 2400 while_each_thread(task, t) 2401 task_io_accounting_add(&acct, &t->ioac); 2402 2403 unlock_task_sighand(task, &flags); 2404 } 2405 result = sprintf(buffer, 2406 "rchar: %llu\n" 2407 "wchar: %llu\n" 2408 "syscr: %llu\n" 2409 "syscw: %llu\n" 2410 "read_bytes: %llu\n" 2411 "write_bytes: %llu\n" 2412 "cancelled_write_bytes: %llu\n", 2413 (unsigned long long)acct.rchar, 2414 (unsigned long long)acct.wchar, 2415 (unsigned long long)acct.syscr, 2416 (unsigned long long)acct.syscw, 2417 (unsigned long long)acct.read_bytes, 2418 (unsigned long long)acct.write_bytes, 2419 (unsigned long long)acct.cancelled_write_bytes); 2420 out_unlock: 2421 mutex_unlock(&task->signal->cred_guard_mutex); 2422 return result; 2423 } 2424 2425 static int proc_tid_io_accounting(struct task_struct *task, char *buffer) 2426 { 2427 return do_io_accounting(task, buffer, 0); 2428 } 2429 2430 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer) 2431 { 2432 return do_io_accounting(task, buffer, 1); 2433 } 2434 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2435 2436 #ifdef CONFIG_USER_NS 2437 static int proc_id_map_open(struct inode *inode, struct file *file, 2438 struct seq_operations *seq_ops) 2439 { 2440 struct user_namespace *ns = NULL; 2441 struct task_struct *task; 2442 struct seq_file *seq; 2443 int ret = -EINVAL; 2444 2445 task = get_proc_task(inode); 2446 if (task) { 2447 rcu_read_lock(); 2448 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2449 rcu_read_unlock(); 2450 put_task_struct(task); 2451 } 2452 if (!ns) 2453 goto err; 2454 2455 ret = seq_open(file, seq_ops); 2456 if (ret) 2457 goto err_put_ns; 2458 2459 seq = file->private_data; 2460 seq->private = ns; 2461 2462 return 0; 2463 err_put_ns: 2464 put_user_ns(ns); 2465 err: 2466 return ret; 2467 } 2468 2469 static int proc_id_map_release(struct inode *inode, struct file *file) 2470 { 2471 struct seq_file *seq = file->private_data; 2472 struct user_namespace *ns = seq->private; 2473 put_user_ns(ns); 2474 return seq_release(inode, file); 2475 } 2476 2477 static int proc_uid_map_open(struct inode *inode, struct file *file) 2478 { 2479 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2480 } 2481 2482 static int proc_gid_map_open(struct inode *inode, struct file *file) 2483 { 2484 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2485 } 2486 2487 static int proc_projid_map_open(struct inode *inode, struct file *file) 2488 { 2489 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2490 } 2491 2492 static const struct file_operations proc_uid_map_operations = { 2493 .open = proc_uid_map_open, 2494 .write = proc_uid_map_write, 2495 .read = seq_read, 2496 .llseek = seq_lseek, 2497 .release = proc_id_map_release, 2498 }; 2499 2500 static const struct file_operations proc_gid_map_operations = { 2501 .open = proc_gid_map_open, 2502 .write = proc_gid_map_write, 2503 .read = seq_read, 2504 .llseek = seq_lseek, 2505 .release = proc_id_map_release, 2506 }; 2507 2508 static const struct file_operations proc_projid_map_operations = { 2509 .open = proc_projid_map_open, 2510 .write = proc_projid_map_write, 2511 .read = seq_read, 2512 .llseek = seq_lseek, 2513 .release = proc_id_map_release, 2514 }; 2515 #endif /* CONFIG_USER_NS */ 2516 2517 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2518 struct pid *pid, struct task_struct *task) 2519 { 2520 int err = lock_trace(task); 2521 if (!err) { 2522 seq_printf(m, "%08x\n", task->personality); 2523 unlock_trace(task); 2524 } 2525 return err; 2526 } 2527 2528 /* 2529 * Thread groups 2530 */ 2531 static const struct file_operations proc_task_operations; 2532 static const struct inode_operations proc_task_inode_operations; 2533 2534 static const struct pid_entry tgid_base_stuff[] = { 2535 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2536 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2537 #ifdef CONFIG_CHECKPOINT_RESTORE 2538 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2539 #endif 2540 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2541 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2542 #ifdef CONFIG_NET 2543 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2544 #endif 2545 REG("environ", S_IRUSR, proc_environ_operations), 2546 INF("auxv", S_IRUSR, proc_pid_auxv), 2547 ONE("status", S_IRUGO, proc_pid_status), 2548 ONE("personality", S_IRUGO, proc_pid_personality), 2549 INF("limits", S_IRUGO, proc_pid_limits), 2550 #ifdef CONFIG_SCHED_DEBUG 2551 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2552 #endif 2553 #ifdef CONFIG_SCHED_AUTOGROUP 2554 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2555 #endif 2556 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2557 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2558 INF("syscall", S_IRUGO, proc_pid_syscall), 2559 #endif 2560 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2561 ONE("stat", S_IRUGO, proc_tgid_stat), 2562 ONE("statm", S_IRUGO, proc_pid_statm), 2563 REG("maps", S_IRUGO, proc_pid_maps_operations), 2564 #ifdef CONFIG_NUMA 2565 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2566 #endif 2567 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2568 LNK("cwd", proc_cwd_link), 2569 LNK("root", proc_root_link), 2570 LNK("exe", proc_exe_link), 2571 REG("mounts", S_IRUGO, proc_mounts_operations), 2572 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2573 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2574 #ifdef CONFIG_PROC_PAGE_MONITOR 2575 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2576 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2577 REG("pagemap", S_IRUGO, proc_pagemap_operations), 2578 #endif 2579 #ifdef CONFIG_SECURITY 2580 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2581 #endif 2582 #ifdef CONFIG_KALLSYMS 2583 INF("wchan", S_IRUGO, proc_pid_wchan), 2584 #endif 2585 #ifdef CONFIG_STACKTRACE 2586 ONE("stack", S_IRUGO, proc_pid_stack), 2587 #endif 2588 #ifdef CONFIG_SCHEDSTATS 2589 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2590 #endif 2591 #ifdef CONFIG_LATENCYTOP 2592 REG("latency", S_IRUGO, proc_lstats_operations), 2593 #endif 2594 #ifdef CONFIG_PROC_PID_CPUSET 2595 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2596 #endif 2597 #ifdef CONFIG_CGROUPS 2598 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2599 #endif 2600 INF("oom_score", S_IRUGO, proc_oom_score), 2601 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2602 #ifdef CONFIG_AUDITSYSCALL 2603 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2604 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2605 #endif 2606 #ifdef CONFIG_FAULT_INJECTION 2607 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2608 #endif 2609 #ifdef CONFIG_ELF_CORE 2610 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2611 #endif 2612 #ifdef CONFIG_TASK_IO_ACCOUNTING 2613 INF("io", S_IRUSR, proc_tgid_io_accounting), 2614 #endif 2615 #ifdef CONFIG_HARDWALL 2616 INF("hardwall", S_IRUGO, proc_pid_hardwall), 2617 #endif 2618 #ifdef CONFIG_USER_NS 2619 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2620 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2621 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2622 #endif 2623 }; 2624 2625 static int proc_tgid_base_readdir(struct file * filp, 2626 void * dirent, filldir_t filldir) 2627 { 2628 return proc_pident_readdir(filp,dirent,filldir, 2629 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 2630 } 2631 2632 static const struct file_operations proc_tgid_base_operations = { 2633 .read = generic_read_dir, 2634 .readdir = proc_tgid_base_readdir, 2635 .llseek = default_llseek, 2636 }; 2637 2638 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 2639 { 2640 return proc_pident_lookup(dir, dentry, 2641 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2642 } 2643 2644 static const struct inode_operations proc_tgid_base_inode_operations = { 2645 .lookup = proc_tgid_base_lookup, 2646 .getattr = pid_getattr, 2647 .setattr = proc_setattr, 2648 .permission = proc_pid_permission, 2649 }; 2650 2651 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2652 { 2653 struct dentry *dentry, *leader, *dir; 2654 char buf[PROC_NUMBUF]; 2655 struct qstr name; 2656 2657 name.name = buf; 2658 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2659 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2660 if (dentry) { 2661 shrink_dcache_parent(dentry); 2662 d_drop(dentry); 2663 dput(dentry); 2664 } 2665 2666 name.name = buf; 2667 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2668 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2669 if (!leader) 2670 goto out; 2671 2672 name.name = "task"; 2673 name.len = strlen(name.name); 2674 dir = d_hash_and_lookup(leader, &name); 2675 if (!dir) 2676 goto out_put_leader; 2677 2678 name.name = buf; 2679 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2680 dentry = d_hash_and_lookup(dir, &name); 2681 if (dentry) { 2682 shrink_dcache_parent(dentry); 2683 d_drop(dentry); 2684 dput(dentry); 2685 } 2686 2687 dput(dir); 2688 out_put_leader: 2689 dput(leader); 2690 out: 2691 return; 2692 } 2693 2694 /** 2695 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2696 * @task: task that should be flushed. 2697 * 2698 * When flushing dentries from proc, one needs to flush them from global 2699 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2700 * in. This call is supposed to do all of this job. 2701 * 2702 * Looks in the dcache for 2703 * /proc/@pid 2704 * /proc/@tgid/task/@pid 2705 * if either directory is present flushes it and all of it'ts children 2706 * from the dcache. 2707 * 2708 * It is safe and reasonable to cache /proc entries for a task until 2709 * that task exits. After that they just clog up the dcache with 2710 * useless entries, possibly causing useful dcache entries to be 2711 * flushed instead. This routine is proved to flush those useless 2712 * dcache entries at process exit time. 2713 * 2714 * NOTE: This routine is just an optimization so it does not guarantee 2715 * that no dcache entries will exist at process exit time it 2716 * just makes it very unlikely that any will persist. 2717 */ 2718 2719 void proc_flush_task(struct task_struct *task) 2720 { 2721 int i; 2722 struct pid *pid, *tgid; 2723 struct upid *upid; 2724 2725 pid = task_pid(task); 2726 tgid = task_tgid(task); 2727 2728 for (i = 0; i <= pid->level; i++) { 2729 upid = &pid->numbers[i]; 2730 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2731 tgid->numbers[i].nr); 2732 } 2733 2734 upid = &pid->numbers[pid->level]; 2735 if (upid->nr == 1) 2736 pid_ns_release_proc(upid->ns); 2737 } 2738 2739 static struct dentry *proc_pid_instantiate(struct inode *dir, 2740 struct dentry * dentry, 2741 struct task_struct *task, const void *ptr) 2742 { 2743 struct dentry *error = ERR_PTR(-ENOENT); 2744 struct inode *inode; 2745 2746 inode = proc_pid_make_inode(dir->i_sb, task); 2747 if (!inode) 2748 goto out; 2749 2750 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2751 inode->i_op = &proc_tgid_base_inode_operations; 2752 inode->i_fop = &proc_tgid_base_operations; 2753 inode->i_flags|=S_IMMUTABLE; 2754 2755 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff, 2756 ARRAY_SIZE(tgid_base_stuff))); 2757 2758 d_set_d_op(dentry, &pid_dentry_operations); 2759 2760 d_add(dentry, inode); 2761 /* Close the race of the process dying before we return the dentry */ 2762 if (pid_revalidate(dentry, 0)) 2763 error = NULL; 2764 out: 2765 return error; 2766 } 2767 2768 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 2769 { 2770 struct dentry *result; 2771 struct task_struct *task; 2772 unsigned tgid; 2773 struct pid_namespace *ns; 2774 2775 result = proc_base_lookup(dir, dentry); 2776 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) 2777 goto out; 2778 2779 tgid = name_to_int(dentry); 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 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 + ARRAY_SIZE(proc_base_stuff)) 2842 2843 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2844 struct tgid_iter iter) 2845 { 2846 char name[PROC_NUMBUF]; 2847 int len = snprintf(name, sizeof(name), "%d", iter.tgid); 2848 return proc_fill_cache(filp, dirent, filldir, name, len, 2849 proc_pid_instantiate, iter.task, NULL); 2850 } 2851 2852 static int fake_filldir(void *buf, const char *name, int namelen, 2853 loff_t offset, u64 ino, unsigned d_type) 2854 { 2855 return 0; 2856 } 2857 2858 /* for the /proc/ directory itself, after non-process stuff has been done */ 2859 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2860 { 2861 unsigned int nr; 2862 struct task_struct *reaper; 2863 struct tgid_iter iter; 2864 struct pid_namespace *ns; 2865 filldir_t __filldir; 2866 2867 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET) 2868 goto out_no_task; 2869 nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2870 2871 reaper = get_proc_task(filp->f_path.dentry->d_inode); 2872 if (!reaper) 2873 goto out_no_task; 2874 2875 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { 2876 const struct pid_entry *p = &proc_base_stuff[nr]; 2877 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) 2878 goto out; 2879 } 2880 2881 ns = filp->f_dentry->d_sb->s_fs_info; 2882 iter.task = NULL; 2883 iter.tgid = filp->f_pos - TGID_OFFSET; 2884 for (iter = next_tgid(ns, iter); 2885 iter.task; 2886 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2887 if (has_pid_permissions(ns, iter.task, 2)) 2888 __filldir = filldir; 2889 else 2890 __filldir = fake_filldir; 2891 2892 filp->f_pos = iter.tgid + TGID_OFFSET; 2893 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) { 2894 put_task_struct(iter.task); 2895 goto out; 2896 } 2897 } 2898 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; 2899 out: 2900 put_task_struct(reaper); 2901 out_no_task: 2902 return 0; 2903 } 2904 2905 /* 2906 * Tasks 2907 */ 2908 static const struct pid_entry tid_base_stuff[] = { 2909 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2910 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2911 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2912 REG("environ", S_IRUSR, proc_environ_operations), 2913 INF("auxv", S_IRUSR, proc_pid_auxv), 2914 ONE("status", S_IRUGO, proc_pid_status), 2915 ONE("personality", S_IRUGO, proc_pid_personality), 2916 INF("limits", S_IRUGO, proc_pid_limits), 2917 #ifdef CONFIG_SCHED_DEBUG 2918 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2919 #endif 2920 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2921 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2922 INF("syscall", S_IRUGO, proc_pid_syscall), 2923 #endif 2924 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2925 ONE("stat", S_IRUGO, proc_tid_stat), 2926 ONE("statm", S_IRUGO, proc_pid_statm), 2927 REG("maps", S_IRUGO, proc_tid_maps_operations), 2928 #ifdef CONFIG_CHECKPOINT_RESTORE 2929 REG("children", S_IRUGO, proc_tid_children_operations), 2930 #endif 2931 #ifdef CONFIG_NUMA 2932 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 2933 #endif 2934 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2935 LNK("cwd", proc_cwd_link), 2936 LNK("root", proc_root_link), 2937 LNK("exe", proc_exe_link), 2938 REG("mounts", S_IRUGO, proc_mounts_operations), 2939 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2940 #ifdef CONFIG_PROC_PAGE_MONITOR 2941 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2942 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 2943 REG("pagemap", S_IRUGO, proc_pagemap_operations), 2944 #endif 2945 #ifdef CONFIG_SECURITY 2946 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2947 #endif 2948 #ifdef CONFIG_KALLSYMS 2949 INF("wchan", S_IRUGO, proc_pid_wchan), 2950 #endif 2951 #ifdef CONFIG_STACKTRACE 2952 ONE("stack", S_IRUGO, proc_pid_stack), 2953 #endif 2954 #ifdef CONFIG_SCHEDSTATS 2955 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2956 #endif 2957 #ifdef CONFIG_LATENCYTOP 2958 REG("latency", S_IRUGO, proc_lstats_operations), 2959 #endif 2960 #ifdef CONFIG_PROC_PID_CPUSET 2961 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2962 #endif 2963 #ifdef CONFIG_CGROUPS 2964 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2965 #endif 2966 INF("oom_score", S_IRUGO, proc_oom_score), 2967 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2968 #ifdef CONFIG_AUDITSYSCALL 2969 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2970 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2971 #endif 2972 #ifdef CONFIG_FAULT_INJECTION 2973 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2974 #endif 2975 #ifdef CONFIG_TASK_IO_ACCOUNTING 2976 INF("io", S_IRUSR, proc_tid_io_accounting), 2977 #endif 2978 #ifdef CONFIG_HARDWALL 2979 INF("hardwall", S_IRUGO, proc_pid_hardwall), 2980 #endif 2981 #ifdef CONFIG_USER_NS 2982 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2983 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2984 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2985 #endif 2986 }; 2987 2988 static int proc_tid_base_readdir(struct file * filp, 2989 void * dirent, filldir_t filldir) 2990 { 2991 return proc_pident_readdir(filp,dirent,filldir, 2992 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 2993 } 2994 2995 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 2996 { 2997 return proc_pident_lookup(dir, dentry, 2998 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2999 } 3000 3001 static const struct file_operations proc_tid_base_operations = { 3002 .read = generic_read_dir, 3003 .readdir = proc_tid_base_readdir, 3004 .llseek = default_llseek, 3005 }; 3006 3007 static const struct inode_operations proc_tid_base_inode_operations = { 3008 .lookup = proc_tid_base_lookup, 3009 .getattr = pid_getattr, 3010 .setattr = proc_setattr, 3011 }; 3012 3013 static struct dentry *proc_task_instantiate(struct inode *dir, 3014 struct dentry *dentry, struct task_struct *task, const void *ptr) 3015 { 3016 struct dentry *error = ERR_PTR(-ENOENT); 3017 struct inode *inode; 3018 inode = proc_pid_make_inode(dir->i_sb, task); 3019 3020 if (!inode) 3021 goto out; 3022 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 3023 inode->i_op = &proc_tid_base_inode_operations; 3024 inode->i_fop = &proc_tid_base_operations; 3025 inode->i_flags|=S_IMMUTABLE; 3026 3027 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff, 3028 ARRAY_SIZE(tid_base_stuff))); 3029 3030 d_set_d_op(dentry, &pid_dentry_operations); 3031 3032 d_add(dentry, inode); 3033 /* Close the race of the process dying before we return the dentry */ 3034 if (pid_revalidate(dentry, 0)) 3035 error = NULL; 3036 out: 3037 return error; 3038 } 3039 3040 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3041 { 3042 struct dentry *result = ERR_PTR(-ENOENT); 3043 struct task_struct *task; 3044 struct task_struct *leader = get_proc_task(dir); 3045 unsigned tid; 3046 struct pid_namespace *ns; 3047 3048 if (!leader) 3049 goto out_no_task; 3050 3051 tid = name_to_int(dentry); 3052 if (tid == ~0U) 3053 goto out; 3054 3055 ns = dentry->d_sb->s_fs_info; 3056 rcu_read_lock(); 3057 task = find_task_by_pid_ns(tid, ns); 3058 if (task) 3059 get_task_struct(task); 3060 rcu_read_unlock(); 3061 if (!task) 3062 goto out; 3063 if (!same_thread_group(leader, task)) 3064 goto out_drop_task; 3065 3066 result = proc_task_instantiate(dir, dentry, task, NULL); 3067 out_drop_task: 3068 put_task_struct(task); 3069 out: 3070 put_task_struct(leader); 3071 out_no_task: 3072 return result; 3073 } 3074 3075 /* 3076 * Find the first tid of a thread group to return to user space. 3077 * 3078 * Usually this is just the thread group leader, but if the users 3079 * buffer was too small or there was a seek into the middle of the 3080 * directory we have more work todo. 3081 * 3082 * In the case of a short read we start with find_task_by_pid. 3083 * 3084 * In the case of a seek we start with the leader and walk nr 3085 * threads past it. 3086 */ 3087 static struct task_struct *first_tid(struct task_struct *leader, 3088 int tid, int nr, struct pid_namespace *ns) 3089 { 3090 struct task_struct *pos; 3091 3092 rcu_read_lock(); 3093 /* Attempt to start with the pid of a thread */ 3094 if (tid && (nr > 0)) { 3095 pos = find_task_by_pid_ns(tid, ns); 3096 if (pos && (pos->group_leader == leader)) 3097 goto found; 3098 } 3099 3100 /* If nr exceeds the number of threads there is nothing todo */ 3101 pos = NULL; 3102 if (nr && nr >= get_nr_threads(leader)) 3103 goto out; 3104 3105 /* If we haven't found our starting place yet start 3106 * with the leader and walk nr threads forward. 3107 */ 3108 for (pos = leader; nr > 0; --nr) { 3109 pos = next_thread(pos); 3110 if (pos == leader) { 3111 pos = NULL; 3112 goto out; 3113 } 3114 } 3115 found: 3116 get_task_struct(pos); 3117 out: 3118 rcu_read_unlock(); 3119 return pos; 3120 } 3121 3122 /* 3123 * Find the next thread in the thread list. 3124 * Return NULL if there is an error or no next thread. 3125 * 3126 * The reference to the input task_struct is released. 3127 */ 3128 static struct task_struct *next_tid(struct task_struct *start) 3129 { 3130 struct task_struct *pos = NULL; 3131 rcu_read_lock(); 3132 if (pid_alive(start)) { 3133 pos = next_thread(start); 3134 if (thread_group_leader(pos)) 3135 pos = NULL; 3136 else 3137 get_task_struct(pos); 3138 } 3139 rcu_read_unlock(); 3140 put_task_struct(start); 3141 return pos; 3142 } 3143 3144 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 3145 struct task_struct *task, int tid) 3146 { 3147 char name[PROC_NUMBUF]; 3148 int len = snprintf(name, sizeof(name), "%d", tid); 3149 return proc_fill_cache(filp, dirent, filldir, name, len, 3150 proc_task_instantiate, task, NULL); 3151 } 3152 3153 /* for the /proc/TGID/task/ directories */ 3154 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 3155 { 3156 struct dentry *dentry = filp->f_path.dentry; 3157 struct inode *inode = dentry->d_inode; 3158 struct task_struct *leader = NULL; 3159 struct task_struct *task; 3160 int retval = -ENOENT; 3161 ino_t ino; 3162 int tid; 3163 struct pid_namespace *ns; 3164 3165 task = get_proc_task(inode); 3166 if (!task) 3167 goto out_no_task; 3168 rcu_read_lock(); 3169 if (pid_alive(task)) { 3170 leader = task->group_leader; 3171 get_task_struct(leader); 3172 } 3173 rcu_read_unlock(); 3174 put_task_struct(task); 3175 if (!leader) 3176 goto out_no_task; 3177 retval = 0; 3178 3179 switch ((unsigned long)filp->f_pos) { 3180 case 0: 3181 ino = inode->i_ino; 3182 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) 3183 goto out; 3184 filp->f_pos++; 3185 /* fall through */ 3186 case 1: 3187 ino = parent_ino(dentry); 3188 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) 3189 goto out; 3190 filp->f_pos++; 3191 /* fall through */ 3192 } 3193 3194 /* f_version caches the tgid value that the last readdir call couldn't 3195 * return. lseek aka telldir automagically resets f_version to 0. 3196 */ 3197 ns = filp->f_dentry->d_sb->s_fs_info; 3198 tid = (int)filp->f_version; 3199 filp->f_version = 0; 3200 for (task = first_tid(leader, tid, filp->f_pos - 2, ns); 3201 task; 3202 task = next_tid(task), filp->f_pos++) { 3203 tid = task_pid_nr_ns(task, ns); 3204 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { 3205 /* returning this tgid failed, save it as the first 3206 * pid for the next readir call */ 3207 filp->f_version = (u64)tid; 3208 put_task_struct(task); 3209 break; 3210 } 3211 } 3212 out: 3213 put_task_struct(leader); 3214 out_no_task: 3215 return retval; 3216 } 3217 3218 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 3219 { 3220 struct inode *inode = dentry->d_inode; 3221 struct task_struct *p = get_proc_task(inode); 3222 generic_fillattr(inode, stat); 3223 3224 if (p) { 3225 stat->nlink += get_nr_threads(p); 3226 put_task_struct(p); 3227 } 3228 3229 return 0; 3230 } 3231 3232 static const struct inode_operations proc_task_inode_operations = { 3233 .lookup = proc_task_lookup, 3234 .getattr = proc_task_getattr, 3235 .setattr = proc_setattr, 3236 .permission = proc_pid_permission, 3237 }; 3238 3239 static const struct file_operations proc_task_operations = { 3240 .read = generic_read_dir, 3241 .readdir = proc_task_readdir, 3242 .llseek = default_llseek, 3243 }; 3244