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/config.h> 53 #include <linux/errno.h> 54 #include <linux/time.h> 55 #include <linux/proc_fs.h> 56 #include <linux/stat.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/string.h> 61 #include <linux/seq_file.h> 62 #include <linux/namei.h> 63 #include <linux/namespace.h> 64 #include <linux/mm.h> 65 #include <linux/smp_lock.h> 66 #include <linux/rcupdate.h> 67 #include <linux/kallsyms.h> 68 #include <linux/mount.h> 69 #include <linux/security.h> 70 #include <linux/ptrace.h> 71 #include <linux/seccomp.h> 72 #include <linux/cpuset.h> 73 #include <linux/audit.h> 74 #include <linux/poll.h> 75 #include "internal.h" 76 77 /* 78 * For hysterical raisins we keep the same inumbers as in the old procfs. 79 * Feel free to change the macro below - just keep the range distinct from 80 * inumbers of the rest of procfs (currently those are in 0x0000--0xffff). 81 * As soon as we'll get a separate superblock we will be able to forget 82 * about magical ranges too. 83 */ 84 85 #define fake_ino(pid,ino) (((pid)<<16)|(ino)) 86 87 enum pid_directory_inos { 88 PROC_TGID_INO = 2, 89 PROC_TGID_TASK, 90 PROC_TGID_STATUS, 91 PROC_TGID_MEM, 92 #ifdef CONFIG_SECCOMP 93 PROC_TGID_SECCOMP, 94 #endif 95 PROC_TGID_CWD, 96 PROC_TGID_ROOT, 97 PROC_TGID_EXE, 98 PROC_TGID_FD, 99 PROC_TGID_ENVIRON, 100 PROC_TGID_AUXV, 101 PROC_TGID_CMDLINE, 102 PROC_TGID_STAT, 103 PROC_TGID_STATM, 104 PROC_TGID_MAPS, 105 PROC_TGID_NUMA_MAPS, 106 PROC_TGID_MOUNTS, 107 PROC_TGID_MOUNTSTATS, 108 PROC_TGID_WCHAN, 109 #ifdef CONFIG_MMU 110 PROC_TGID_SMAPS, 111 #endif 112 #ifdef CONFIG_SCHEDSTATS 113 PROC_TGID_SCHEDSTAT, 114 #endif 115 #ifdef CONFIG_CPUSETS 116 PROC_TGID_CPUSET, 117 #endif 118 #ifdef CONFIG_SECURITY 119 PROC_TGID_ATTR, 120 PROC_TGID_ATTR_CURRENT, 121 PROC_TGID_ATTR_PREV, 122 PROC_TGID_ATTR_EXEC, 123 PROC_TGID_ATTR_FSCREATE, 124 #endif 125 #ifdef CONFIG_AUDITSYSCALL 126 PROC_TGID_LOGINUID, 127 #endif 128 PROC_TGID_OOM_SCORE, 129 PROC_TGID_OOM_ADJUST, 130 PROC_TID_INO, 131 PROC_TID_STATUS, 132 PROC_TID_MEM, 133 #ifdef CONFIG_SECCOMP 134 PROC_TID_SECCOMP, 135 #endif 136 PROC_TID_CWD, 137 PROC_TID_ROOT, 138 PROC_TID_EXE, 139 PROC_TID_FD, 140 PROC_TID_ENVIRON, 141 PROC_TID_AUXV, 142 PROC_TID_CMDLINE, 143 PROC_TID_STAT, 144 PROC_TID_STATM, 145 PROC_TID_MAPS, 146 PROC_TID_NUMA_MAPS, 147 PROC_TID_MOUNTS, 148 PROC_TID_MOUNTSTATS, 149 PROC_TID_WCHAN, 150 #ifdef CONFIG_MMU 151 PROC_TID_SMAPS, 152 #endif 153 #ifdef CONFIG_SCHEDSTATS 154 PROC_TID_SCHEDSTAT, 155 #endif 156 #ifdef CONFIG_CPUSETS 157 PROC_TID_CPUSET, 158 #endif 159 #ifdef CONFIG_SECURITY 160 PROC_TID_ATTR, 161 PROC_TID_ATTR_CURRENT, 162 PROC_TID_ATTR_PREV, 163 PROC_TID_ATTR_EXEC, 164 PROC_TID_ATTR_FSCREATE, 165 #endif 166 #ifdef CONFIG_AUDITSYSCALL 167 PROC_TID_LOGINUID, 168 #endif 169 PROC_TID_OOM_SCORE, 170 PROC_TID_OOM_ADJUST, 171 172 /* Add new entries before this */ 173 PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */ 174 }; 175 176 struct pid_entry { 177 int type; 178 int len; 179 char *name; 180 mode_t mode; 181 }; 182 183 #define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)} 184 185 static struct pid_entry tgid_base_stuff[] = { 186 E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO), 187 E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 188 E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR), 189 E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR), 190 E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO), 191 E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 192 E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO), 193 E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO), 194 E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO), 195 #ifdef CONFIG_NUMA 196 E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 197 #endif 198 E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 199 #ifdef CONFIG_SECCOMP 200 E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 201 #endif 202 E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 203 E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO), 204 E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO), 205 E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 206 E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR), 207 #ifdef CONFIG_MMU 208 E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO), 209 #endif 210 #ifdef CONFIG_SECURITY 211 E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 212 #endif 213 #ifdef CONFIG_KALLSYMS 214 E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO), 215 #endif 216 #ifdef CONFIG_SCHEDSTATS 217 E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO), 218 #endif 219 #ifdef CONFIG_CPUSETS 220 E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 221 #endif 222 E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 223 E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 224 #ifdef CONFIG_AUDITSYSCALL 225 E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 226 #endif 227 {0,0,NULL,0} 228 }; 229 static struct pid_entry tid_base_stuff[] = { 230 E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 231 E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR), 232 E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR), 233 E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO), 234 E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 235 E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO), 236 E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO), 237 E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO), 238 #ifdef CONFIG_NUMA 239 E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 240 #endif 241 E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 242 #ifdef CONFIG_SECCOMP 243 E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 244 #endif 245 E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 246 E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO), 247 E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO), 248 E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 249 #ifdef CONFIG_MMU 250 E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO), 251 #endif 252 #ifdef CONFIG_SECURITY 253 E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 254 #endif 255 #ifdef CONFIG_KALLSYMS 256 E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO), 257 #endif 258 #ifdef CONFIG_SCHEDSTATS 259 E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO), 260 #endif 261 #ifdef CONFIG_CPUSETS 262 E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 263 #endif 264 E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 265 E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 266 #ifdef CONFIG_AUDITSYSCALL 267 E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 268 #endif 269 {0,0,NULL,0} 270 }; 271 272 #ifdef CONFIG_SECURITY 273 static struct pid_entry tgid_attr_stuff[] = { 274 E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 275 E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 276 E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 277 E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 278 {0,0,NULL,0} 279 }; 280 static struct pid_entry tid_attr_stuff[] = { 281 E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 282 E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 283 E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 284 E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 285 {0,0,NULL,0} 286 }; 287 #endif 288 289 #undef E 290 291 static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 292 { 293 struct task_struct *task = proc_task(inode); 294 struct files_struct *files; 295 struct file *file; 296 int fd = proc_type(inode) - PROC_TID_FD_DIR; 297 298 files = get_files_struct(task); 299 if (files) { 300 /* 301 * We are not taking a ref to the file structure, so we must 302 * hold ->file_lock. 303 */ 304 spin_lock(&files->file_lock); 305 file = fcheck_files(files, fd); 306 if (file) { 307 *mnt = mntget(file->f_vfsmnt); 308 *dentry = dget(file->f_dentry); 309 spin_unlock(&files->file_lock); 310 put_files_struct(files); 311 return 0; 312 } 313 spin_unlock(&files->file_lock); 314 put_files_struct(files); 315 } 316 return -ENOENT; 317 } 318 319 static struct fs_struct *get_fs_struct(struct task_struct *task) 320 { 321 struct fs_struct *fs; 322 task_lock(task); 323 fs = task->fs; 324 if(fs) 325 atomic_inc(&fs->count); 326 task_unlock(task); 327 return fs; 328 } 329 330 static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 331 { 332 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 333 int result = -ENOENT; 334 if (fs) { 335 read_lock(&fs->lock); 336 *mnt = mntget(fs->pwdmnt); 337 *dentry = dget(fs->pwd); 338 read_unlock(&fs->lock); 339 result = 0; 340 put_fs_struct(fs); 341 } 342 return result; 343 } 344 345 static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 346 { 347 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 348 int result = -ENOENT; 349 if (fs) { 350 read_lock(&fs->lock); 351 *mnt = mntget(fs->rootmnt); 352 *dentry = dget(fs->root); 353 read_unlock(&fs->lock); 354 result = 0; 355 put_fs_struct(fs); 356 } 357 return result; 358 } 359 360 361 /* Same as proc_root_link, but this addionally tries to get fs from other 362 * threads in the group */ 363 static int proc_task_root_link(struct inode *inode, struct dentry **dentry, 364 struct vfsmount **mnt) 365 { 366 struct fs_struct *fs; 367 int result = -ENOENT; 368 struct task_struct *leader = proc_task(inode); 369 370 task_lock(leader); 371 fs = leader->fs; 372 if (fs) { 373 atomic_inc(&fs->count); 374 task_unlock(leader); 375 } else { 376 /* Try to get fs from other threads */ 377 task_unlock(leader); 378 read_lock(&tasklist_lock); 379 if (pid_alive(leader)) { 380 struct task_struct *task = leader; 381 382 while ((task = next_thread(task)) != leader) { 383 task_lock(task); 384 fs = task->fs; 385 if (fs) { 386 atomic_inc(&fs->count); 387 task_unlock(task); 388 break; 389 } 390 task_unlock(task); 391 } 392 } 393 read_unlock(&tasklist_lock); 394 } 395 396 if (fs) { 397 read_lock(&fs->lock); 398 *mnt = mntget(fs->rootmnt); 399 *dentry = dget(fs->root); 400 read_unlock(&fs->lock); 401 result = 0; 402 put_fs_struct(fs); 403 } 404 return result; 405 } 406 407 408 #define MAY_PTRACE(task) \ 409 (task == current || \ 410 (task->parent == current && \ 411 (task->ptrace & PT_PTRACED) && \ 412 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ 413 security_ptrace(current,task) == 0)) 414 415 static int proc_pid_environ(struct task_struct *task, char * buffer) 416 { 417 int res = 0; 418 struct mm_struct *mm = get_task_mm(task); 419 if (mm) { 420 unsigned int len = mm->env_end - mm->env_start; 421 if (len > PAGE_SIZE) 422 len = PAGE_SIZE; 423 res = access_process_vm(task, mm->env_start, buffer, len, 0); 424 if (!ptrace_may_attach(task)) 425 res = -ESRCH; 426 mmput(mm); 427 } 428 return res; 429 } 430 431 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 432 { 433 int res = 0; 434 unsigned int len; 435 struct mm_struct *mm = get_task_mm(task); 436 if (!mm) 437 goto out; 438 if (!mm->arg_end) 439 goto out_mm; /* Shh! No looking before we're done */ 440 441 len = mm->arg_end - mm->arg_start; 442 443 if (len > PAGE_SIZE) 444 len = PAGE_SIZE; 445 446 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 447 448 // If the nul at the end of args has been overwritten, then 449 // assume application is using setproctitle(3). 450 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 451 len = strnlen(buffer, res); 452 if (len < res) { 453 res = len; 454 } else { 455 len = mm->env_end - mm->env_start; 456 if (len > PAGE_SIZE - res) 457 len = PAGE_SIZE - res; 458 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 459 res = strnlen(buffer, res); 460 } 461 } 462 out_mm: 463 mmput(mm); 464 out: 465 return res; 466 } 467 468 static int proc_pid_auxv(struct task_struct *task, char *buffer) 469 { 470 int res = 0; 471 struct mm_struct *mm = get_task_mm(task); 472 if (mm) { 473 unsigned int nwords = 0; 474 do 475 nwords += 2; 476 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 477 res = nwords * sizeof(mm->saved_auxv[0]); 478 if (res > PAGE_SIZE) 479 res = PAGE_SIZE; 480 memcpy(buffer, mm->saved_auxv, res); 481 mmput(mm); 482 } 483 return res; 484 } 485 486 487 #ifdef CONFIG_KALLSYMS 488 /* 489 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 490 * Returns the resolved symbol. If that fails, simply return the address. 491 */ 492 static int proc_pid_wchan(struct task_struct *task, char *buffer) 493 { 494 char *modname; 495 const char *sym_name; 496 unsigned long wchan, size, offset; 497 char namebuf[KSYM_NAME_LEN+1]; 498 499 wchan = get_wchan(task); 500 501 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); 502 if (sym_name) 503 return sprintf(buffer, "%s", sym_name); 504 return sprintf(buffer, "%lu", wchan); 505 } 506 #endif /* CONFIG_KALLSYMS */ 507 508 #ifdef CONFIG_SCHEDSTATS 509 /* 510 * Provides /proc/PID/schedstat 511 */ 512 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 513 { 514 return sprintf(buffer, "%lu %lu %lu\n", 515 task->sched_info.cpu_time, 516 task->sched_info.run_delay, 517 task->sched_info.pcnt); 518 } 519 #endif 520 521 /* The badness from the OOM killer */ 522 unsigned long badness(struct task_struct *p, unsigned long uptime); 523 static int proc_oom_score(struct task_struct *task, char *buffer) 524 { 525 unsigned long points; 526 struct timespec uptime; 527 528 do_posix_clock_monotonic_gettime(&uptime); 529 points = badness(task, uptime.tv_sec); 530 return sprintf(buffer, "%lu\n", points); 531 } 532 533 /************************************************************************/ 534 /* Here the fs part begins */ 535 /************************************************************************/ 536 537 /* permission checks */ 538 539 /* If the process being read is separated by chroot from the reading process, 540 * don't let the reader access the threads. 541 * 542 * note: this does dput(root) and mntput(vfsmnt) on exit. 543 */ 544 static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt) 545 { 546 struct dentry *de, *base; 547 struct vfsmount *our_vfsmnt, *mnt; 548 int res = 0; 549 550 read_lock(¤t->fs->lock); 551 our_vfsmnt = mntget(current->fs->rootmnt); 552 base = dget(current->fs->root); 553 read_unlock(¤t->fs->lock); 554 555 spin_lock(&vfsmount_lock); 556 de = root; 557 mnt = vfsmnt; 558 559 while (mnt != our_vfsmnt) { 560 if (mnt == mnt->mnt_parent) 561 goto out; 562 de = mnt->mnt_mountpoint; 563 mnt = mnt->mnt_parent; 564 } 565 566 if (!is_subdir(de, base)) 567 goto out; 568 spin_unlock(&vfsmount_lock); 569 570 exit: 571 dput(base); 572 mntput(our_vfsmnt); 573 dput(root); 574 mntput(vfsmnt); 575 return res; 576 out: 577 spin_unlock(&vfsmount_lock); 578 res = -EACCES; 579 goto exit; 580 } 581 582 static int proc_check_root(struct inode *inode) 583 { 584 struct dentry *root; 585 struct vfsmount *vfsmnt; 586 587 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */ 588 return -ENOENT; 589 return proc_check_chroot(root, vfsmnt); 590 } 591 592 static int proc_permission(struct inode *inode, int mask, struct nameidata *nd) 593 { 594 if (generic_permission(inode, mask, NULL) != 0) 595 return -EACCES; 596 return proc_check_root(inode); 597 } 598 599 static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd) 600 { 601 struct dentry *root; 602 struct vfsmount *vfsmnt; 603 604 if (generic_permission(inode, mask, NULL) != 0) 605 return -EACCES; 606 607 if (proc_task_root_link(inode, &root, &vfsmnt)) 608 return -ENOENT; 609 610 return proc_check_chroot(root, vfsmnt); 611 } 612 613 extern struct seq_operations proc_pid_maps_op; 614 static int maps_open(struct inode *inode, struct file *file) 615 { 616 struct task_struct *task = proc_task(inode); 617 int ret = seq_open(file, &proc_pid_maps_op); 618 if (!ret) { 619 struct seq_file *m = file->private_data; 620 m->private = task; 621 } 622 return ret; 623 } 624 625 static struct file_operations proc_maps_operations = { 626 .open = maps_open, 627 .read = seq_read, 628 .llseek = seq_lseek, 629 .release = seq_release, 630 }; 631 632 #ifdef CONFIG_NUMA 633 extern struct seq_operations proc_pid_numa_maps_op; 634 static int numa_maps_open(struct inode *inode, struct file *file) 635 { 636 struct task_struct *task = proc_task(inode); 637 int ret = seq_open(file, &proc_pid_numa_maps_op); 638 if (!ret) { 639 struct seq_file *m = file->private_data; 640 m->private = task; 641 } 642 return ret; 643 } 644 645 static struct file_operations proc_numa_maps_operations = { 646 .open = numa_maps_open, 647 .read = seq_read, 648 .llseek = seq_lseek, 649 .release = seq_release, 650 }; 651 #endif 652 653 #ifdef CONFIG_MMU 654 extern struct seq_operations proc_pid_smaps_op; 655 static int smaps_open(struct inode *inode, struct file *file) 656 { 657 struct task_struct *task = proc_task(inode); 658 int ret = seq_open(file, &proc_pid_smaps_op); 659 if (!ret) { 660 struct seq_file *m = file->private_data; 661 m->private = task; 662 } 663 return ret; 664 } 665 666 static struct file_operations proc_smaps_operations = { 667 .open = smaps_open, 668 .read = seq_read, 669 .llseek = seq_lseek, 670 .release = seq_release, 671 }; 672 #endif 673 674 extern struct seq_operations mounts_op; 675 struct proc_mounts { 676 struct seq_file m; 677 int event; 678 }; 679 680 static int mounts_open(struct inode *inode, struct file *file) 681 { 682 struct task_struct *task = proc_task(inode); 683 struct namespace *namespace; 684 struct proc_mounts *p; 685 int ret = -EINVAL; 686 687 task_lock(task); 688 namespace = task->namespace; 689 if (namespace) 690 get_namespace(namespace); 691 task_unlock(task); 692 693 if (namespace) { 694 ret = -ENOMEM; 695 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 696 if (p) { 697 file->private_data = &p->m; 698 ret = seq_open(file, &mounts_op); 699 if (!ret) { 700 p->m.private = namespace; 701 p->event = namespace->event; 702 return 0; 703 } 704 kfree(p); 705 } 706 put_namespace(namespace); 707 } 708 return ret; 709 } 710 711 static int mounts_release(struct inode *inode, struct file *file) 712 { 713 struct seq_file *m = file->private_data; 714 struct namespace *namespace = m->private; 715 put_namespace(namespace); 716 return seq_release(inode, file); 717 } 718 719 static unsigned mounts_poll(struct file *file, poll_table *wait) 720 { 721 struct proc_mounts *p = file->private_data; 722 struct namespace *ns = p->m.private; 723 unsigned res = 0; 724 725 poll_wait(file, &ns->poll, wait); 726 727 spin_lock(&vfsmount_lock); 728 if (p->event != ns->event) { 729 p->event = ns->event; 730 res = POLLERR; 731 } 732 spin_unlock(&vfsmount_lock); 733 734 return res; 735 } 736 737 static struct file_operations proc_mounts_operations = { 738 .open = mounts_open, 739 .read = seq_read, 740 .llseek = seq_lseek, 741 .release = mounts_release, 742 .poll = mounts_poll, 743 }; 744 745 extern struct seq_operations mountstats_op; 746 static int mountstats_open(struct inode *inode, struct file *file) 747 { 748 struct task_struct *task = proc_task(inode); 749 int ret = seq_open(file, &mountstats_op); 750 751 if (!ret) { 752 struct seq_file *m = file->private_data; 753 struct namespace *namespace; 754 task_lock(task); 755 namespace = task->namespace; 756 if (namespace) 757 get_namespace(namespace); 758 task_unlock(task); 759 760 if (namespace) 761 m->private = namespace; 762 else { 763 seq_release(inode, file); 764 ret = -EINVAL; 765 } 766 } 767 return ret; 768 } 769 770 static struct file_operations proc_mountstats_operations = { 771 .open = mountstats_open, 772 .read = seq_read, 773 .llseek = seq_lseek, 774 .release = mounts_release, 775 }; 776 777 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 778 779 static ssize_t proc_info_read(struct file * file, char __user * buf, 780 size_t count, loff_t *ppos) 781 { 782 struct inode * inode = file->f_dentry->d_inode; 783 unsigned long page; 784 ssize_t length; 785 struct task_struct *task = proc_task(inode); 786 787 if (count > PROC_BLOCK_SIZE) 788 count = PROC_BLOCK_SIZE; 789 if (!(page = __get_free_page(GFP_KERNEL))) 790 return -ENOMEM; 791 792 length = PROC_I(inode)->op.proc_read(task, (char*)page); 793 794 if (length >= 0) 795 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 796 free_page(page); 797 return length; 798 } 799 800 static struct file_operations proc_info_file_operations = { 801 .read = proc_info_read, 802 }; 803 804 static int mem_open(struct inode* inode, struct file* file) 805 { 806 file->private_data = (void*)((long)current->self_exec_id); 807 return 0; 808 } 809 810 static ssize_t mem_read(struct file * file, char __user * buf, 811 size_t count, loff_t *ppos) 812 { 813 struct task_struct *task = proc_task(file->f_dentry->d_inode); 814 char *page; 815 unsigned long src = *ppos; 816 int ret = -ESRCH; 817 struct mm_struct *mm; 818 819 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 820 goto out; 821 822 ret = -ENOMEM; 823 page = (char *)__get_free_page(GFP_USER); 824 if (!page) 825 goto out; 826 827 ret = 0; 828 829 mm = get_task_mm(task); 830 if (!mm) 831 goto out_free; 832 833 ret = -EIO; 834 835 if (file->private_data != (void*)((long)current->self_exec_id)) 836 goto out_put; 837 838 ret = 0; 839 840 while (count > 0) { 841 int this_len, retval; 842 843 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 844 retval = access_process_vm(task, src, page, this_len, 0); 845 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { 846 if (!ret) 847 ret = -EIO; 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; 862 863 out_put: 864 mmput(mm); 865 out_free: 866 free_page((unsigned long) page); 867 out: 868 return ret; 869 } 870 871 #define mem_write NULL 872 873 #ifndef mem_write 874 /* This is a security hazard */ 875 static ssize_t mem_write(struct file * file, const char * buf, 876 size_t count, loff_t *ppos) 877 { 878 int copied = 0; 879 char *page; 880 struct task_struct *task = proc_task(file->f_dentry->d_inode); 881 unsigned long dst = *ppos; 882 883 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 884 return -ESRCH; 885 886 page = (char *)__get_free_page(GFP_USER); 887 if (!page) 888 return -ENOMEM; 889 890 while (count > 0) { 891 int this_len, retval; 892 893 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 894 if (copy_from_user(page, buf, this_len)) { 895 copied = -EFAULT; 896 break; 897 } 898 retval = access_process_vm(task, dst, page, this_len, 1); 899 if (!retval) { 900 if (!copied) 901 copied = -EIO; 902 break; 903 } 904 copied += retval; 905 buf += retval; 906 dst += retval; 907 count -= retval; 908 } 909 *ppos = dst; 910 free_page((unsigned long) page); 911 return copied; 912 } 913 #endif 914 915 static loff_t mem_lseek(struct file * file, loff_t offset, int orig) 916 { 917 switch (orig) { 918 case 0: 919 file->f_pos = offset; 920 break; 921 case 1: 922 file->f_pos += offset; 923 break; 924 default: 925 return -EINVAL; 926 } 927 force_successful_syscall_return(); 928 return file->f_pos; 929 } 930 931 static struct file_operations proc_mem_operations = { 932 .llseek = mem_lseek, 933 .read = mem_read, 934 .write = mem_write, 935 .open = mem_open, 936 }; 937 938 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 939 size_t count, loff_t *ppos) 940 { 941 struct task_struct *task = proc_task(file->f_dentry->d_inode); 942 char buffer[8]; 943 size_t len; 944 int oom_adjust = task->oomkilladj; 945 loff_t __ppos = *ppos; 946 947 len = sprintf(buffer, "%i\n", oom_adjust); 948 if (__ppos >= len) 949 return 0; 950 if (count > len-__ppos) 951 count = len-__ppos; 952 if (copy_to_user(buf, buffer + __ppos, count)) 953 return -EFAULT; 954 *ppos = __ppos + count; 955 return count; 956 } 957 958 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 959 size_t count, loff_t *ppos) 960 { 961 struct task_struct *task = proc_task(file->f_dentry->d_inode); 962 char buffer[8], *end; 963 int oom_adjust; 964 965 if (!capable(CAP_SYS_RESOURCE)) 966 return -EPERM; 967 memset(buffer, 0, 8); 968 if (count > 6) 969 count = 6; 970 if (copy_from_user(buffer, buf, count)) 971 return -EFAULT; 972 oom_adjust = simple_strtol(buffer, &end, 0); 973 if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE) 974 return -EINVAL; 975 if (*end == '\n') 976 end++; 977 task->oomkilladj = oom_adjust; 978 if (end - buffer == 0) 979 return -EIO; 980 return end - buffer; 981 } 982 983 static struct file_operations proc_oom_adjust_operations = { 984 .read = oom_adjust_read, 985 .write = oom_adjust_write, 986 }; 987 988 static struct inode_operations proc_mem_inode_operations = { 989 .permission = proc_permission, 990 }; 991 992 #ifdef CONFIG_AUDITSYSCALL 993 #define TMPBUFLEN 21 994 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 995 size_t count, loff_t *ppos) 996 { 997 struct inode * inode = file->f_dentry->d_inode; 998 struct task_struct *task = proc_task(inode); 999 ssize_t length; 1000 char tmpbuf[TMPBUFLEN]; 1001 1002 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1003 audit_get_loginuid(task->audit_context)); 1004 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1005 } 1006 1007 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1008 size_t count, loff_t *ppos) 1009 { 1010 struct inode * inode = file->f_dentry->d_inode; 1011 char *page, *tmp; 1012 ssize_t length; 1013 struct task_struct *task = proc_task(inode); 1014 uid_t loginuid; 1015 1016 if (!capable(CAP_AUDIT_CONTROL)) 1017 return -EPERM; 1018 1019 if (current != task) 1020 return -EPERM; 1021 1022 if (count > PAGE_SIZE) 1023 count = PAGE_SIZE; 1024 1025 if (*ppos != 0) { 1026 /* No partial writes. */ 1027 return -EINVAL; 1028 } 1029 page = (char*)__get_free_page(GFP_USER); 1030 if (!page) 1031 return -ENOMEM; 1032 length = -EFAULT; 1033 if (copy_from_user(page, buf, count)) 1034 goto out_free_page; 1035 1036 loginuid = simple_strtoul(page, &tmp, 10); 1037 if (tmp == page) { 1038 length = -EINVAL; 1039 goto out_free_page; 1040 1041 } 1042 length = audit_set_loginuid(task, loginuid); 1043 if (likely(length == 0)) 1044 length = count; 1045 1046 out_free_page: 1047 free_page((unsigned long) page); 1048 return length; 1049 } 1050 1051 static struct file_operations proc_loginuid_operations = { 1052 .read = proc_loginuid_read, 1053 .write = proc_loginuid_write, 1054 }; 1055 #endif 1056 1057 #ifdef CONFIG_SECCOMP 1058 static ssize_t seccomp_read(struct file *file, char __user *buf, 1059 size_t count, loff_t *ppos) 1060 { 1061 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1062 char __buf[20]; 1063 loff_t __ppos = *ppos; 1064 size_t len; 1065 1066 /* no need to print the trailing zero, so use only len */ 1067 len = sprintf(__buf, "%u\n", tsk->seccomp.mode); 1068 if (__ppos >= len) 1069 return 0; 1070 if (count > len - __ppos) 1071 count = len - __ppos; 1072 if (copy_to_user(buf, __buf + __ppos, count)) 1073 return -EFAULT; 1074 *ppos = __ppos + count; 1075 return count; 1076 } 1077 1078 static ssize_t seccomp_write(struct file *file, const char __user *buf, 1079 size_t count, loff_t *ppos) 1080 { 1081 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1082 char __buf[20], *end; 1083 unsigned int seccomp_mode; 1084 1085 /* can set it only once to be even more secure */ 1086 if (unlikely(tsk->seccomp.mode)) 1087 return -EPERM; 1088 1089 memset(__buf, 0, sizeof(__buf)); 1090 count = min(count, sizeof(__buf) - 1); 1091 if (copy_from_user(__buf, buf, count)) 1092 return -EFAULT; 1093 seccomp_mode = simple_strtoul(__buf, &end, 0); 1094 if (*end == '\n') 1095 end++; 1096 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { 1097 tsk->seccomp.mode = seccomp_mode; 1098 set_tsk_thread_flag(tsk, TIF_SECCOMP); 1099 } else 1100 return -EINVAL; 1101 if (unlikely(!(end - __buf))) 1102 return -EIO; 1103 return end - __buf; 1104 } 1105 1106 static struct file_operations proc_seccomp_operations = { 1107 .read = seccomp_read, 1108 .write = seccomp_write, 1109 }; 1110 #endif /* CONFIG_SECCOMP */ 1111 1112 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1113 { 1114 struct inode *inode = dentry->d_inode; 1115 int error = -EACCES; 1116 1117 /* We don't need a base pointer in the /proc filesystem */ 1118 path_release(nd); 1119 1120 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1121 goto out; 1122 error = proc_check_root(inode); 1123 if (error) 1124 goto out; 1125 1126 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); 1127 nd->last_type = LAST_BIND; 1128 out: 1129 return ERR_PTR(error); 1130 } 1131 1132 static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, 1133 char __user *buffer, int buflen) 1134 { 1135 struct inode * inode; 1136 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; 1137 int len; 1138 1139 if (!tmp) 1140 return -ENOMEM; 1141 1142 inode = dentry->d_inode; 1143 path = d_path(dentry, mnt, tmp, PAGE_SIZE); 1144 len = PTR_ERR(path); 1145 if (IS_ERR(path)) 1146 goto out; 1147 len = tmp + PAGE_SIZE - 1 - path; 1148 1149 if (len > buflen) 1150 len = buflen; 1151 if (copy_to_user(buffer, path, len)) 1152 len = -EFAULT; 1153 out: 1154 free_page((unsigned long)tmp); 1155 return len; 1156 } 1157 1158 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1159 { 1160 int error = -EACCES; 1161 struct inode *inode = dentry->d_inode; 1162 struct dentry *de; 1163 struct vfsmount *mnt = NULL; 1164 1165 lock_kernel(); 1166 1167 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1168 goto out; 1169 error = proc_check_root(inode); 1170 if (error) 1171 goto out; 1172 1173 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); 1174 if (error) 1175 goto out; 1176 1177 error = do_proc_readlink(de, mnt, buffer, buflen); 1178 dput(de); 1179 mntput(mnt); 1180 out: 1181 unlock_kernel(); 1182 return error; 1183 } 1184 1185 static struct inode_operations proc_pid_link_inode_operations = { 1186 .readlink = proc_pid_readlink, 1187 .follow_link = proc_pid_follow_link 1188 }; 1189 1190 #define NUMBUF 10 1191 1192 static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) 1193 { 1194 struct inode *inode = filp->f_dentry->d_inode; 1195 struct task_struct *p = proc_task(inode); 1196 unsigned int fd, tid, ino; 1197 int retval; 1198 char buf[NUMBUF]; 1199 struct files_struct * files; 1200 struct fdtable *fdt; 1201 1202 retval = -ENOENT; 1203 if (!pid_alive(p)) 1204 goto out; 1205 retval = 0; 1206 tid = p->pid; 1207 1208 fd = filp->f_pos; 1209 switch (fd) { 1210 case 0: 1211 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1212 goto out; 1213 filp->f_pos++; 1214 case 1: 1215 ino = fake_ino(tid, PROC_TID_INO); 1216 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1217 goto out; 1218 filp->f_pos++; 1219 default: 1220 files = get_files_struct(p); 1221 if (!files) 1222 goto out; 1223 rcu_read_lock(); 1224 fdt = files_fdtable(files); 1225 for (fd = filp->f_pos-2; 1226 fd < fdt->max_fds; 1227 fd++, filp->f_pos++) { 1228 unsigned int i,j; 1229 1230 if (!fcheck_files(files, fd)) 1231 continue; 1232 rcu_read_unlock(); 1233 1234 j = NUMBUF; 1235 i = fd; 1236 do { 1237 j--; 1238 buf[j] = '0' + (i % 10); 1239 i /= 10; 1240 } while (i); 1241 1242 ino = fake_ino(tid, PROC_TID_FD_DIR + fd); 1243 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) { 1244 rcu_read_lock(); 1245 break; 1246 } 1247 rcu_read_lock(); 1248 } 1249 rcu_read_unlock(); 1250 put_files_struct(files); 1251 } 1252 out: 1253 return retval; 1254 } 1255 1256 static int proc_pident_readdir(struct file *filp, 1257 void *dirent, filldir_t filldir, 1258 struct pid_entry *ents, unsigned int nents) 1259 { 1260 int i; 1261 int pid; 1262 struct dentry *dentry = filp->f_dentry; 1263 struct inode *inode = dentry->d_inode; 1264 struct pid_entry *p; 1265 ino_t ino; 1266 int ret; 1267 1268 ret = -ENOENT; 1269 if (!pid_alive(proc_task(inode))) 1270 goto out; 1271 1272 ret = 0; 1273 pid = proc_task(inode)->pid; 1274 i = filp->f_pos; 1275 switch (i) { 1276 case 0: 1277 ino = inode->i_ino; 1278 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 1279 goto out; 1280 i++; 1281 filp->f_pos++; 1282 /* fall through */ 1283 case 1: 1284 ino = parent_ino(dentry); 1285 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1286 goto out; 1287 i++; 1288 filp->f_pos++; 1289 /* fall through */ 1290 default: 1291 i -= 2; 1292 if (i >= nents) { 1293 ret = 1; 1294 goto out; 1295 } 1296 p = ents + i; 1297 while (p->name) { 1298 if (filldir(dirent, p->name, p->len, filp->f_pos, 1299 fake_ino(pid, p->type), p->mode >> 12) < 0) 1300 goto out; 1301 filp->f_pos++; 1302 p++; 1303 } 1304 } 1305 1306 ret = 1; 1307 out: 1308 return ret; 1309 } 1310 1311 static int proc_tgid_base_readdir(struct file * filp, 1312 void * dirent, filldir_t filldir) 1313 { 1314 return proc_pident_readdir(filp,dirent,filldir, 1315 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 1316 } 1317 1318 static int proc_tid_base_readdir(struct file * filp, 1319 void * dirent, filldir_t filldir) 1320 { 1321 return proc_pident_readdir(filp,dirent,filldir, 1322 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 1323 } 1324 1325 /* building an inode */ 1326 1327 static int task_dumpable(struct task_struct *task) 1328 { 1329 int dumpable = 0; 1330 struct mm_struct *mm; 1331 1332 task_lock(task); 1333 mm = task->mm; 1334 if (mm) 1335 dumpable = mm->dumpable; 1336 task_unlock(task); 1337 if(dumpable == 1) 1338 return 1; 1339 return 0; 1340 } 1341 1342 1343 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino) 1344 { 1345 struct inode * inode; 1346 struct proc_inode *ei; 1347 1348 /* We need a new inode */ 1349 1350 inode = new_inode(sb); 1351 if (!inode) 1352 goto out; 1353 1354 /* Common stuff */ 1355 ei = PROC_I(inode); 1356 ei->task = NULL; 1357 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1358 inode->i_ino = fake_ino(task->pid, ino); 1359 1360 if (!pid_alive(task)) 1361 goto out_unlock; 1362 1363 /* 1364 * grab the reference to task. 1365 */ 1366 get_task_struct(task); 1367 ei->task = task; 1368 ei->type = ino; 1369 inode->i_uid = 0; 1370 inode->i_gid = 0; 1371 if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) { 1372 inode->i_uid = task->euid; 1373 inode->i_gid = task->egid; 1374 } 1375 security_task_to_inode(task, inode); 1376 1377 out: 1378 return inode; 1379 1380 out_unlock: 1381 ei->pde = NULL; 1382 iput(inode); 1383 return NULL; 1384 } 1385 1386 /* dentry stuff */ 1387 1388 /* 1389 * Exceptional case: normally we are not allowed to unhash a busy 1390 * directory. In this case, however, we can do it - no aliasing problems 1391 * due to the way we treat inodes. 1392 * 1393 * Rewrite the inode's ownerships here because the owning task may have 1394 * performed a setuid(), etc. 1395 */ 1396 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1397 { 1398 struct inode *inode = dentry->d_inode; 1399 struct task_struct *task = proc_task(inode); 1400 if (pid_alive(task)) { 1401 if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) { 1402 inode->i_uid = task->euid; 1403 inode->i_gid = task->egid; 1404 } else { 1405 inode->i_uid = 0; 1406 inode->i_gid = 0; 1407 } 1408 security_task_to_inode(task, inode); 1409 return 1; 1410 } 1411 d_drop(dentry); 1412 return 0; 1413 } 1414 1415 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1416 { 1417 struct inode *inode = dentry->d_inode; 1418 struct task_struct *task = proc_task(inode); 1419 int fd = proc_type(inode) - PROC_TID_FD_DIR; 1420 struct files_struct *files; 1421 1422 files = get_files_struct(task); 1423 if (files) { 1424 rcu_read_lock(); 1425 if (fcheck_files(files, fd)) { 1426 rcu_read_unlock(); 1427 put_files_struct(files); 1428 if (task_dumpable(task)) { 1429 inode->i_uid = task->euid; 1430 inode->i_gid = task->egid; 1431 } else { 1432 inode->i_uid = 0; 1433 inode->i_gid = 0; 1434 } 1435 security_task_to_inode(task, inode); 1436 return 1; 1437 } 1438 rcu_read_unlock(); 1439 put_files_struct(files); 1440 } 1441 d_drop(dentry); 1442 return 0; 1443 } 1444 1445 static void pid_base_iput(struct dentry *dentry, struct inode *inode) 1446 { 1447 struct task_struct *task = proc_task(inode); 1448 spin_lock(&task->proc_lock); 1449 if (task->proc_dentry == dentry) 1450 task->proc_dentry = NULL; 1451 spin_unlock(&task->proc_lock); 1452 iput(inode); 1453 } 1454 1455 static int pid_delete_dentry(struct dentry * dentry) 1456 { 1457 /* Is the task we represent dead? 1458 * If so, then don't put the dentry on the lru list, 1459 * kill it immediately. 1460 */ 1461 return !pid_alive(proc_task(dentry->d_inode)); 1462 } 1463 1464 static struct dentry_operations tid_fd_dentry_operations = 1465 { 1466 .d_revalidate = tid_fd_revalidate, 1467 .d_delete = pid_delete_dentry, 1468 }; 1469 1470 static struct dentry_operations pid_dentry_operations = 1471 { 1472 .d_revalidate = pid_revalidate, 1473 .d_delete = pid_delete_dentry, 1474 }; 1475 1476 static struct dentry_operations pid_base_dentry_operations = 1477 { 1478 .d_revalidate = pid_revalidate, 1479 .d_iput = pid_base_iput, 1480 .d_delete = pid_delete_dentry, 1481 }; 1482 1483 /* Lookups */ 1484 1485 static unsigned name_to_int(struct dentry *dentry) 1486 { 1487 const char *name = dentry->d_name.name; 1488 int len = dentry->d_name.len; 1489 unsigned n = 0; 1490 1491 if (len > 1 && *name == '0') 1492 goto out; 1493 while (len-- > 0) { 1494 unsigned c = *name++ - '0'; 1495 if (c > 9) 1496 goto out; 1497 if (n >= (~0U-9)/10) 1498 goto out; 1499 n *= 10; 1500 n += c; 1501 } 1502 return n; 1503 out: 1504 return ~0U; 1505 } 1506 1507 /* SMP-safe */ 1508 static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) 1509 { 1510 struct task_struct *task = proc_task(dir); 1511 unsigned fd = name_to_int(dentry); 1512 struct file * file; 1513 struct files_struct * files; 1514 struct inode *inode; 1515 struct proc_inode *ei; 1516 1517 if (fd == ~0U) 1518 goto out; 1519 if (!pid_alive(task)) 1520 goto out; 1521 1522 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd); 1523 if (!inode) 1524 goto out; 1525 ei = PROC_I(inode); 1526 files = get_files_struct(task); 1527 if (!files) 1528 goto out_unlock; 1529 inode->i_mode = S_IFLNK; 1530 1531 /* 1532 * We are not taking a ref to the file structure, so we must 1533 * hold ->file_lock. 1534 */ 1535 spin_lock(&files->file_lock); 1536 file = fcheck_files(files, fd); 1537 if (!file) 1538 goto out_unlock2; 1539 if (file->f_mode & 1) 1540 inode->i_mode |= S_IRUSR | S_IXUSR; 1541 if (file->f_mode & 2) 1542 inode->i_mode |= S_IWUSR | S_IXUSR; 1543 spin_unlock(&files->file_lock); 1544 put_files_struct(files); 1545 inode->i_op = &proc_pid_link_inode_operations; 1546 inode->i_size = 64; 1547 ei->op.proc_get_link = proc_fd_link; 1548 dentry->d_op = &tid_fd_dentry_operations; 1549 d_add(dentry, inode); 1550 return NULL; 1551 1552 out_unlock2: 1553 spin_unlock(&files->file_lock); 1554 put_files_struct(files); 1555 out_unlock: 1556 iput(inode); 1557 out: 1558 return ERR_PTR(-ENOENT); 1559 } 1560 1561 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); 1562 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); 1563 1564 static struct file_operations proc_fd_operations = { 1565 .read = generic_read_dir, 1566 .readdir = proc_readfd, 1567 }; 1568 1569 static struct file_operations proc_task_operations = { 1570 .read = generic_read_dir, 1571 .readdir = proc_task_readdir, 1572 }; 1573 1574 /* 1575 * proc directories can do almost nothing.. 1576 */ 1577 static struct inode_operations proc_fd_inode_operations = { 1578 .lookup = proc_lookupfd, 1579 .permission = proc_permission, 1580 }; 1581 1582 static struct inode_operations proc_task_inode_operations = { 1583 .lookup = proc_task_lookup, 1584 .permission = proc_task_permission, 1585 }; 1586 1587 #ifdef CONFIG_SECURITY 1588 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 1589 size_t count, loff_t *ppos) 1590 { 1591 struct inode * inode = file->f_dentry->d_inode; 1592 unsigned long page; 1593 ssize_t length; 1594 struct task_struct *task = proc_task(inode); 1595 1596 if (count > PAGE_SIZE) 1597 count = PAGE_SIZE; 1598 if (!(page = __get_free_page(GFP_KERNEL))) 1599 return -ENOMEM; 1600 1601 length = security_getprocattr(task, 1602 (char*)file->f_dentry->d_name.name, 1603 (void*)page, count); 1604 if (length >= 0) 1605 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 1606 free_page(page); 1607 return length; 1608 } 1609 1610 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 1611 size_t count, loff_t *ppos) 1612 { 1613 struct inode * inode = file->f_dentry->d_inode; 1614 char *page; 1615 ssize_t length; 1616 struct task_struct *task = proc_task(inode); 1617 1618 if (count > PAGE_SIZE) 1619 count = PAGE_SIZE; 1620 if (*ppos != 0) { 1621 /* No partial writes. */ 1622 return -EINVAL; 1623 } 1624 page = (char*)__get_free_page(GFP_USER); 1625 if (!page) 1626 return -ENOMEM; 1627 length = -EFAULT; 1628 if (copy_from_user(page, buf, count)) 1629 goto out; 1630 1631 length = security_setprocattr(task, 1632 (char*)file->f_dentry->d_name.name, 1633 (void*)page, count); 1634 out: 1635 free_page((unsigned long) page); 1636 return length; 1637 } 1638 1639 static struct file_operations proc_pid_attr_operations = { 1640 .read = proc_pid_attr_read, 1641 .write = proc_pid_attr_write, 1642 }; 1643 1644 static struct file_operations proc_tid_attr_operations; 1645 static struct inode_operations proc_tid_attr_inode_operations; 1646 static struct file_operations proc_tgid_attr_operations; 1647 static struct inode_operations proc_tgid_attr_inode_operations; 1648 #endif 1649 1650 static int get_tid_list(int index, unsigned int *tids, struct inode *dir); 1651 1652 /* SMP-safe */ 1653 static struct dentry *proc_pident_lookup(struct inode *dir, 1654 struct dentry *dentry, 1655 struct pid_entry *ents) 1656 { 1657 struct inode *inode; 1658 int error; 1659 struct task_struct *task = proc_task(dir); 1660 struct pid_entry *p; 1661 struct proc_inode *ei; 1662 1663 error = -ENOENT; 1664 inode = NULL; 1665 1666 if (!pid_alive(task)) 1667 goto out; 1668 1669 for (p = ents; p->name; p++) { 1670 if (p->len != dentry->d_name.len) 1671 continue; 1672 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1673 break; 1674 } 1675 if (!p->name) 1676 goto out; 1677 1678 error = -EINVAL; 1679 inode = proc_pid_make_inode(dir->i_sb, task, p->type); 1680 if (!inode) 1681 goto out; 1682 1683 ei = PROC_I(inode); 1684 inode->i_mode = p->mode; 1685 /* 1686 * Yes, it does not scale. And it should not. Don't add 1687 * new entries into /proc/<tgid>/ without very good reasons. 1688 */ 1689 switch(p->type) { 1690 case PROC_TGID_TASK: 1691 inode->i_nlink = 2 + get_tid_list(2, NULL, dir); 1692 inode->i_op = &proc_task_inode_operations; 1693 inode->i_fop = &proc_task_operations; 1694 break; 1695 case PROC_TID_FD: 1696 case PROC_TGID_FD: 1697 inode->i_nlink = 2; 1698 inode->i_op = &proc_fd_inode_operations; 1699 inode->i_fop = &proc_fd_operations; 1700 break; 1701 case PROC_TID_EXE: 1702 case PROC_TGID_EXE: 1703 inode->i_op = &proc_pid_link_inode_operations; 1704 ei->op.proc_get_link = proc_exe_link; 1705 break; 1706 case PROC_TID_CWD: 1707 case PROC_TGID_CWD: 1708 inode->i_op = &proc_pid_link_inode_operations; 1709 ei->op.proc_get_link = proc_cwd_link; 1710 break; 1711 case PROC_TID_ROOT: 1712 case PROC_TGID_ROOT: 1713 inode->i_op = &proc_pid_link_inode_operations; 1714 ei->op.proc_get_link = proc_root_link; 1715 break; 1716 case PROC_TID_ENVIRON: 1717 case PROC_TGID_ENVIRON: 1718 inode->i_fop = &proc_info_file_operations; 1719 ei->op.proc_read = proc_pid_environ; 1720 break; 1721 case PROC_TID_AUXV: 1722 case PROC_TGID_AUXV: 1723 inode->i_fop = &proc_info_file_operations; 1724 ei->op.proc_read = proc_pid_auxv; 1725 break; 1726 case PROC_TID_STATUS: 1727 case PROC_TGID_STATUS: 1728 inode->i_fop = &proc_info_file_operations; 1729 ei->op.proc_read = proc_pid_status; 1730 break; 1731 case PROC_TID_STAT: 1732 inode->i_fop = &proc_info_file_operations; 1733 ei->op.proc_read = proc_tid_stat; 1734 break; 1735 case PROC_TGID_STAT: 1736 inode->i_fop = &proc_info_file_operations; 1737 ei->op.proc_read = proc_tgid_stat; 1738 break; 1739 case PROC_TID_CMDLINE: 1740 case PROC_TGID_CMDLINE: 1741 inode->i_fop = &proc_info_file_operations; 1742 ei->op.proc_read = proc_pid_cmdline; 1743 break; 1744 case PROC_TID_STATM: 1745 case PROC_TGID_STATM: 1746 inode->i_fop = &proc_info_file_operations; 1747 ei->op.proc_read = proc_pid_statm; 1748 break; 1749 case PROC_TID_MAPS: 1750 case PROC_TGID_MAPS: 1751 inode->i_fop = &proc_maps_operations; 1752 break; 1753 #ifdef CONFIG_NUMA 1754 case PROC_TID_NUMA_MAPS: 1755 case PROC_TGID_NUMA_MAPS: 1756 inode->i_fop = &proc_numa_maps_operations; 1757 break; 1758 #endif 1759 case PROC_TID_MEM: 1760 case PROC_TGID_MEM: 1761 inode->i_op = &proc_mem_inode_operations; 1762 inode->i_fop = &proc_mem_operations; 1763 break; 1764 #ifdef CONFIG_SECCOMP 1765 case PROC_TID_SECCOMP: 1766 case PROC_TGID_SECCOMP: 1767 inode->i_fop = &proc_seccomp_operations; 1768 break; 1769 #endif /* CONFIG_SECCOMP */ 1770 case PROC_TID_MOUNTS: 1771 case PROC_TGID_MOUNTS: 1772 inode->i_fop = &proc_mounts_operations; 1773 break; 1774 #ifdef CONFIG_MMU 1775 case PROC_TID_SMAPS: 1776 case PROC_TGID_SMAPS: 1777 inode->i_fop = &proc_smaps_operations; 1778 break; 1779 #endif 1780 case PROC_TID_MOUNTSTATS: 1781 case PROC_TGID_MOUNTSTATS: 1782 inode->i_fop = &proc_mountstats_operations; 1783 break; 1784 #ifdef CONFIG_SECURITY 1785 case PROC_TID_ATTR: 1786 inode->i_nlink = 2; 1787 inode->i_op = &proc_tid_attr_inode_operations; 1788 inode->i_fop = &proc_tid_attr_operations; 1789 break; 1790 case PROC_TGID_ATTR: 1791 inode->i_nlink = 2; 1792 inode->i_op = &proc_tgid_attr_inode_operations; 1793 inode->i_fop = &proc_tgid_attr_operations; 1794 break; 1795 case PROC_TID_ATTR_CURRENT: 1796 case PROC_TGID_ATTR_CURRENT: 1797 case PROC_TID_ATTR_PREV: 1798 case PROC_TGID_ATTR_PREV: 1799 case PROC_TID_ATTR_EXEC: 1800 case PROC_TGID_ATTR_EXEC: 1801 case PROC_TID_ATTR_FSCREATE: 1802 case PROC_TGID_ATTR_FSCREATE: 1803 inode->i_fop = &proc_pid_attr_operations; 1804 break; 1805 #endif 1806 #ifdef CONFIG_KALLSYMS 1807 case PROC_TID_WCHAN: 1808 case PROC_TGID_WCHAN: 1809 inode->i_fop = &proc_info_file_operations; 1810 ei->op.proc_read = proc_pid_wchan; 1811 break; 1812 #endif 1813 #ifdef CONFIG_SCHEDSTATS 1814 case PROC_TID_SCHEDSTAT: 1815 case PROC_TGID_SCHEDSTAT: 1816 inode->i_fop = &proc_info_file_operations; 1817 ei->op.proc_read = proc_pid_schedstat; 1818 break; 1819 #endif 1820 #ifdef CONFIG_CPUSETS 1821 case PROC_TID_CPUSET: 1822 case PROC_TGID_CPUSET: 1823 inode->i_fop = &proc_cpuset_operations; 1824 break; 1825 #endif 1826 case PROC_TID_OOM_SCORE: 1827 case PROC_TGID_OOM_SCORE: 1828 inode->i_fop = &proc_info_file_operations; 1829 ei->op.proc_read = proc_oom_score; 1830 break; 1831 case PROC_TID_OOM_ADJUST: 1832 case PROC_TGID_OOM_ADJUST: 1833 inode->i_fop = &proc_oom_adjust_operations; 1834 break; 1835 #ifdef CONFIG_AUDITSYSCALL 1836 case PROC_TID_LOGINUID: 1837 case PROC_TGID_LOGINUID: 1838 inode->i_fop = &proc_loginuid_operations; 1839 break; 1840 #endif 1841 default: 1842 printk("procfs: impossible type (%d)",p->type); 1843 iput(inode); 1844 return ERR_PTR(-EINVAL); 1845 } 1846 dentry->d_op = &pid_dentry_operations; 1847 d_add(dentry, inode); 1848 return NULL; 1849 1850 out: 1851 return ERR_PTR(error); 1852 } 1853 1854 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1855 return proc_pident_lookup(dir, dentry, tgid_base_stuff); 1856 } 1857 1858 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1859 return proc_pident_lookup(dir, dentry, tid_base_stuff); 1860 } 1861 1862 static struct file_operations proc_tgid_base_operations = { 1863 .read = generic_read_dir, 1864 .readdir = proc_tgid_base_readdir, 1865 }; 1866 1867 static struct file_operations proc_tid_base_operations = { 1868 .read = generic_read_dir, 1869 .readdir = proc_tid_base_readdir, 1870 }; 1871 1872 static struct inode_operations proc_tgid_base_inode_operations = { 1873 .lookup = proc_tgid_base_lookup, 1874 }; 1875 1876 static struct inode_operations proc_tid_base_inode_operations = { 1877 .lookup = proc_tid_base_lookup, 1878 }; 1879 1880 #ifdef CONFIG_SECURITY 1881 static int proc_tgid_attr_readdir(struct file * filp, 1882 void * dirent, filldir_t filldir) 1883 { 1884 return proc_pident_readdir(filp,dirent,filldir, 1885 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff)); 1886 } 1887 1888 static int proc_tid_attr_readdir(struct file * filp, 1889 void * dirent, filldir_t filldir) 1890 { 1891 return proc_pident_readdir(filp,dirent,filldir, 1892 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff)); 1893 } 1894 1895 static struct file_operations proc_tgid_attr_operations = { 1896 .read = generic_read_dir, 1897 .readdir = proc_tgid_attr_readdir, 1898 }; 1899 1900 static struct file_operations proc_tid_attr_operations = { 1901 .read = generic_read_dir, 1902 .readdir = proc_tid_attr_readdir, 1903 }; 1904 1905 static struct dentry *proc_tgid_attr_lookup(struct inode *dir, 1906 struct dentry *dentry, struct nameidata *nd) 1907 { 1908 return proc_pident_lookup(dir, dentry, tgid_attr_stuff); 1909 } 1910 1911 static struct dentry *proc_tid_attr_lookup(struct inode *dir, 1912 struct dentry *dentry, struct nameidata *nd) 1913 { 1914 return proc_pident_lookup(dir, dentry, tid_attr_stuff); 1915 } 1916 1917 static struct inode_operations proc_tgid_attr_inode_operations = { 1918 .lookup = proc_tgid_attr_lookup, 1919 }; 1920 1921 static struct inode_operations proc_tid_attr_inode_operations = { 1922 .lookup = proc_tid_attr_lookup, 1923 }; 1924 #endif 1925 1926 /* 1927 * /proc/self: 1928 */ 1929 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 1930 int buflen) 1931 { 1932 char tmp[30]; 1933 sprintf(tmp, "%d", current->tgid); 1934 return vfs_readlink(dentry,buffer,buflen,tmp); 1935 } 1936 1937 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 1938 { 1939 char tmp[30]; 1940 sprintf(tmp, "%d", current->tgid); 1941 return ERR_PTR(vfs_follow_link(nd,tmp)); 1942 } 1943 1944 static struct inode_operations proc_self_inode_operations = { 1945 .readlink = proc_self_readlink, 1946 .follow_link = proc_self_follow_link, 1947 }; 1948 1949 /** 1950 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache. 1951 * @p: task that should be flushed. 1952 * 1953 * Drops the /proc/@pid dcache entry from the hash chains. 1954 * 1955 * Dropping /proc/@pid entries and detach_pid must be synchroneous, 1956 * otherwise e.g. /proc/@pid/exe might point to the wrong executable, 1957 * if the pid value is immediately reused. This is enforced by 1958 * - caller must acquire spin_lock(p->proc_lock) 1959 * - must be called before detach_pid() 1960 * - proc_pid_lookup acquires proc_lock, and checks that 1961 * the target is not dead by looking at the attach count 1962 * of PIDTYPE_PID. 1963 */ 1964 1965 struct dentry *proc_pid_unhash(struct task_struct *p) 1966 { 1967 struct dentry *proc_dentry; 1968 1969 proc_dentry = p->proc_dentry; 1970 if (proc_dentry != NULL) { 1971 1972 spin_lock(&dcache_lock); 1973 spin_lock(&proc_dentry->d_lock); 1974 if (!d_unhashed(proc_dentry)) { 1975 dget_locked(proc_dentry); 1976 __d_drop(proc_dentry); 1977 spin_unlock(&proc_dentry->d_lock); 1978 } else { 1979 spin_unlock(&proc_dentry->d_lock); 1980 proc_dentry = NULL; 1981 } 1982 spin_unlock(&dcache_lock); 1983 } 1984 return proc_dentry; 1985 } 1986 1987 /** 1988 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries 1989 * @proc_dentry: directoy to prune. 1990 * 1991 * Shrink the /proc directory that was used by the just killed thread. 1992 */ 1993 1994 void proc_pid_flush(struct dentry *proc_dentry) 1995 { 1996 might_sleep(); 1997 if(proc_dentry != NULL) { 1998 shrink_dcache_parent(proc_dentry); 1999 dput(proc_dentry); 2000 } 2001 } 2002 2003 /* SMP-safe */ 2004 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2005 { 2006 struct task_struct *task; 2007 struct inode *inode; 2008 struct proc_inode *ei; 2009 unsigned tgid; 2010 int died; 2011 2012 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) { 2013 inode = new_inode(dir->i_sb); 2014 if (!inode) 2015 return ERR_PTR(-ENOMEM); 2016 ei = PROC_I(inode); 2017 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2018 inode->i_ino = fake_ino(0, PROC_TGID_INO); 2019 ei->pde = NULL; 2020 inode->i_mode = S_IFLNK|S_IRWXUGO; 2021 inode->i_uid = inode->i_gid = 0; 2022 inode->i_size = 64; 2023 inode->i_op = &proc_self_inode_operations; 2024 d_add(dentry, inode); 2025 return NULL; 2026 } 2027 tgid = name_to_int(dentry); 2028 if (tgid == ~0U) 2029 goto out; 2030 2031 read_lock(&tasklist_lock); 2032 task = find_task_by_pid(tgid); 2033 if (task) 2034 get_task_struct(task); 2035 read_unlock(&tasklist_lock); 2036 if (!task) 2037 goto out; 2038 2039 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO); 2040 2041 2042 if (!inode) { 2043 put_task_struct(task); 2044 goto out; 2045 } 2046 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2047 inode->i_op = &proc_tgid_base_inode_operations; 2048 inode->i_fop = &proc_tgid_base_operations; 2049 inode->i_flags|=S_IMMUTABLE; 2050 #ifdef CONFIG_SECURITY 2051 inode->i_nlink = 5; 2052 #else 2053 inode->i_nlink = 4; 2054 #endif 2055 2056 dentry->d_op = &pid_base_dentry_operations; 2057 2058 died = 0; 2059 d_add(dentry, inode); 2060 spin_lock(&task->proc_lock); 2061 task->proc_dentry = dentry; 2062 if (!pid_alive(task)) { 2063 dentry = proc_pid_unhash(task); 2064 died = 1; 2065 } 2066 spin_unlock(&task->proc_lock); 2067 2068 put_task_struct(task); 2069 if (died) { 2070 proc_pid_flush(dentry); 2071 goto out; 2072 } 2073 return NULL; 2074 out: 2075 return ERR_PTR(-ENOENT); 2076 } 2077 2078 /* SMP-safe */ 2079 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2080 { 2081 struct task_struct *task; 2082 struct task_struct *leader = proc_task(dir); 2083 struct inode *inode; 2084 unsigned tid; 2085 2086 tid = name_to_int(dentry); 2087 if (tid == ~0U) 2088 goto out; 2089 2090 read_lock(&tasklist_lock); 2091 task = find_task_by_pid(tid); 2092 if (task) 2093 get_task_struct(task); 2094 read_unlock(&tasklist_lock); 2095 if (!task) 2096 goto out; 2097 if (leader->tgid != task->tgid) 2098 goto out_drop_task; 2099 2100 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO); 2101 2102 2103 if (!inode) 2104 goto out_drop_task; 2105 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2106 inode->i_op = &proc_tid_base_inode_operations; 2107 inode->i_fop = &proc_tid_base_operations; 2108 inode->i_flags|=S_IMMUTABLE; 2109 #ifdef CONFIG_SECURITY 2110 inode->i_nlink = 4; 2111 #else 2112 inode->i_nlink = 3; 2113 #endif 2114 2115 dentry->d_op = &pid_base_dentry_operations; 2116 2117 d_add(dentry, inode); 2118 2119 put_task_struct(task); 2120 return NULL; 2121 out_drop_task: 2122 put_task_struct(task); 2123 out: 2124 return ERR_PTR(-ENOENT); 2125 } 2126 2127 #define PROC_NUMBUF 10 2128 #define PROC_MAXPIDS 20 2129 2130 /* 2131 * Get a few tgid's to return for filldir - we need to hold the 2132 * tasklist lock while doing this, and we must release it before 2133 * we actually do the filldir itself, so we use a temp buffer.. 2134 */ 2135 static int get_tgid_list(int index, unsigned long version, unsigned int *tgids) 2136 { 2137 struct task_struct *p; 2138 int nr_tgids = 0; 2139 2140 index--; 2141 read_lock(&tasklist_lock); 2142 p = NULL; 2143 if (version) { 2144 p = find_task_by_pid(version); 2145 if (p && !thread_group_leader(p)) 2146 p = NULL; 2147 } 2148 2149 if (p) 2150 index = 0; 2151 else 2152 p = next_task(&init_task); 2153 2154 for ( ; p != &init_task; p = next_task(p)) { 2155 int tgid = p->pid; 2156 if (!pid_alive(p)) 2157 continue; 2158 if (--index >= 0) 2159 continue; 2160 tgids[nr_tgids] = tgid; 2161 nr_tgids++; 2162 if (nr_tgids >= PROC_MAXPIDS) 2163 break; 2164 } 2165 read_unlock(&tasklist_lock); 2166 return nr_tgids; 2167 } 2168 2169 /* 2170 * Get a few tid's to return for filldir - we need to hold the 2171 * tasklist lock while doing this, and we must release it before 2172 * we actually do the filldir itself, so we use a temp buffer.. 2173 */ 2174 static int get_tid_list(int index, unsigned int *tids, struct inode *dir) 2175 { 2176 struct task_struct *leader_task = proc_task(dir); 2177 struct task_struct *task = leader_task; 2178 int nr_tids = 0; 2179 2180 index -= 2; 2181 read_lock(&tasklist_lock); 2182 /* 2183 * The starting point task (leader_task) might be an already 2184 * unlinked task, which cannot be used to access the task-list 2185 * via next_thread(). 2186 */ 2187 if (pid_alive(task)) do { 2188 int tid = task->pid; 2189 2190 if (--index >= 0) 2191 continue; 2192 if (tids != NULL) 2193 tids[nr_tids] = tid; 2194 nr_tids++; 2195 if (nr_tids >= PROC_MAXPIDS) 2196 break; 2197 } while ((task = next_thread(task)) != leader_task); 2198 read_unlock(&tasklist_lock); 2199 return nr_tids; 2200 } 2201 2202 /* for the /proc/ directory itself, after non-process stuff has been done */ 2203 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2204 { 2205 unsigned int tgid_array[PROC_MAXPIDS]; 2206 char buf[PROC_NUMBUF]; 2207 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2208 unsigned int nr_tgids, i; 2209 int next_tgid; 2210 2211 if (!nr) { 2212 ino_t ino = fake_ino(0,PROC_TGID_INO); 2213 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0) 2214 return 0; 2215 filp->f_pos++; 2216 nr++; 2217 } 2218 2219 /* f_version caches the tgid value that the last readdir call couldn't 2220 * return. lseek aka telldir automagically resets f_version to 0. 2221 */ 2222 next_tgid = filp->f_version; 2223 filp->f_version = 0; 2224 for (;;) { 2225 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array); 2226 if (!nr_tgids) { 2227 /* no more entries ! */ 2228 break; 2229 } 2230 next_tgid = 0; 2231 2232 /* do not use the last found pid, reserve it for next_tgid */ 2233 if (nr_tgids == PROC_MAXPIDS) { 2234 nr_tgids--; 2235 next_tgid = tgid_array[nr_tgids]; 2236 } 2237 2238 for (i=0;i<nr_tgids;i++) { 2239 int tgid = tgid_array[i]; 2240 ino_t ino = fake_ino(tgid,PROC_TGID_INO); 2241 unsigned long j = PROC_NUMBUF; 2242 2243 do 2244 buf[--j] = '0' + (tgid % 10); 2245 while ((tgid /= 10) != 0); 2246 2247 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) { 2248 /* returning this tgid failed, save it as the first 2249 * pid for the next readir call */ 2250 filp->f_version = tgid_array[i]; 2251 goto out; 2252 } 2253 filp->f_pos++; 2254 nr++; 2255 } 2256 } 2257 out: 2258 return 0; 2259 } 2260 2261 /* for the /proc/TGID/task/ directories */ 2262 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 2263 { 2264 unsigned int tid_array[PROC_MAXPIDS]; 2265 char buf[PROC_NUMBUF]; 2266 unsigned int nr_tids, i; 2267 struct dentry *dentry = filp->f_dentry; 2268 struct inode *inode = dentry->d_inode; 2269 int retval = -ENOENT; 2270 ino_t ino; 2271 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ 2272 2273 if (!pid_alive(proc_task(inode))) 2274 goto out; 2275 retval = 0; 2276 2277 switch (pos) { 2278 case 0: 2279 ino = inode->i_ino; 2280 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) 2281 goto out; 2282 pos++; 2283 /* fall through */ 2284 case 1: 2285 ino = parent_ino(dentry); 2286 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) 2287 goto out; 2288 pos++; 2289 /* fall through */ 2290 } 2291 2292 nr_tids = get_tid_list(pos, tid_array, inode); 2293 inode->i_nlink = pos + nr_tids; 2294 2295 for (i = 0; i < nr_tids; i++) { 2296 unsigned long j = PROC_NUMBUF; 2297 int tid = tid_array[i]; 2298 2299 ino = fake_ino(tid,PROC_TID_INO); 2300 2301 do 2302 buf[--j] = '0' + (tid % 10); 2303 while ((tid /= 10) != 0); 2304 2305 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0) 2306 break; 2307 pos++; 2308 } 2309 out: 2310 filp->f_pos = pos; 2311 return retval; 2312 } 2313