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 rcu_read_lock(); 301 file = fcheck_files(files, fd); 302 if (file) { 303 *mnt = mntget(file->f_vfsmnt); 304 *dentry = dget(file->f_dentry); 305 rcu_read_unlock(); 306 put_files_struct(files); 307 return 0; 308 } 309 rcu_read_unlock(); 310 put_files_struct(files); 311 } 312 return -ENOENT; 313 } 314 315 static struct fs_struct *get_fs_struct(struct task_struct *task) 316 { 317 struct fs_struct *fs; 318 task_lock(task); 319 fs = task->fs; 320 if(fs) 321 atomic_inc(&fs->count); 322 task_unlock(task); 323 return fs; 324 } 325 326 static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 327 { 328 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 329 int result = -ENOENT; 330 if (fs) { 331 read_lock(&fs->lock); 332 *mnt = mntget(fs->pwdmnt); 333 *dentry = dget(fs->pwd); 334 read_unlock(&fs->lock); 335 result = 0; 336 put_fs_struct(fs); 337 } 338 return result; 339 } 340 341 static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 342 { 343 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 344 int result = -ENOENT; 345 if (fs) { 346 read_lock(&fs->lock); 347 *mnt = mntget(fs->rootmnt); 348 *dentry = dget(fs->root); 349 read_unlock(&fs->lock); 350 result = 0; 351 put_fs_struct(fs); 352 } 353 return result; 354 } 355 356 357 /* Same as proc_root_link, but this addionally tries to get fs from other 358 * threads in the group */ 359 static int proc_task_root_link(struct inode *inode, struct dentry **dentry, 360 struct vfsmount **mnt) 361 { 362 struct fs_struct *fs; 363 int result = -ENOENT; 364 struct task_struct *leader = proc_task(inode); 365 366 task_lock(leader); 367 fs = leader->fs; 368 if (fs) { 369 atomic_inc(&fs->count); 370 task_unlock(leader); 371 } else { 372 /* Try to get fs from other threads */ 373 task_unlock(leader); 374 read_lock(&tasklist_lock); 375 if (pid_alive(leader)) { 376 struct task_struct *task = leader; 377 378 while ((task = next_thread(task)) != leader) { 379 task_lock(task); 380 fs = task->fs; 381 if (fs) { 382 atomic_inc(&fs->count); 383 task_unlock(task); 384 break; 385 } 386 task_unlock(task); 387 } 388 } 389 read_unlock(&tasklist_lock); 390 } 391 392 if (fs) { 393 read_lock(&fs->lock); 394 *mnt = mntget(fs->rootmnt); 395 *dentry = dget(fs->root); 396 read_unlock(&fs->lock); 397 result = 0; 398 put_fs_struct(fs); 399 } 400 return result; 401 } 402 403 404 #define MAY_PTRACE(task) \ 405 (task == current || \ 406 (task->parent == current && \ 407 (task->ptrace & PT_PTRACED) && \ 408 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ 409 security_ptrace(current,task) == 0)) 410 411 static int proc_pid_environ(struct task_struct *task, char * buffer) 412 { 413 int res = 0; 414 struct mm_struct *mm = get_task_mm(task); 415 if (mm) { 416 unsigned int len = mm->env_end - mm->env_start; 417 if (len > PAGE_SIZE) 418 len = PAGE_SIZE; 419 res = access_process_vm(task, mm->env_start, buffer, len, 0); 420 if (!ptrace_may_attach(task)) 421 res = -ESRCH; 422 mmput(mm); 423 } 424 return res; 425 } 426 427 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 428 { 429 int res = 0; 430 unsigned int len; 431 struct mm_struct *mm = get_task_mm(task); 432 if (!mm) 433 goto out; 434 if (!mm->arg_end) 435 goto out_mm; /* Shh! No looking before we're done */ 436 437 len = mm->arg_end - mm->arg_start; 438 439 if (len > PAGE_SIZE) 440 len = PAGE_SIZE; 441 442 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 443 444 // If the nul at the end of args has been overwritten, then 445 // assume application is using setproctitle(3). 446 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 447 len = strnlen(buffer, res); 448 if (len < res) { 449 res = len; 450 } else { 451 len = mm->env_end - mm->env_start; 452 if (len > PAGE_SIZE - res) 453 len = PAGE_SIZE - res; 454 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 455 res = strnlen(buffer, res); 456 } 457 } 458 out_mm: 459 mmput(mm); 460 out: 461 return res; 462 } 463 464 static int proc_pid_auxv(struct task_struct *task, char *buffer) 465 { 466 int res = 0; 467 struct mm_struct *mm = get_task_mm(task); 468 if (mm) { 469 unsigned int nwords = 0; 470 do 471 nwords += 2; 472 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 473 res = nwords * sizeof(mm->saved_auxv[0]); 474 if (res > PAGE_SIZE) 475 res = PAGE_SIZE; 476 memcpy(buffer, mm->saved_auxv, res); 477 mmput(mm); 478 } 479 return res; 480 } 481 482 483 #ifdef CONFIG_KALLSYMS 484 /* 485 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 486 * Returns the resolved symbol. If that fails, simply return the address. 487 */ 488 static int proc_pid_wchan(struct task_struct *task, char *buffer) 489 { 490 char *modname; 491 const char *sym_name; 492 unsigned long wchan, size, offset; 493 char namebuf[KSYM_NAME_LEN+1]; 494 495 wchan = get_wchan(task); 496 497 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); 498 if (sym_name) 499 return sprintf(buffer, "%s", sym_name); 500 return sprintf(buffer, "%lu", wchan); 501 } 502 #endif /* CONFIG_KALLSYMS */ 503 504 #ifdef CONFIG_SCHEDSTATS 505 /* 506 * Provides /proc/PID/schedstat 507 */ 508 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 509 { 510 return sprintf(buffer, "%lu %lu %lu\n", 511 task->sched_info.cpu_time, 512 task->sched_info.run_delay, 513 task->sched_info.pcnt); 514 } 515 #endif 516 517 /* The badness from the OOM killer */ 518 unsigned long badness(struct task_struct *p, unsigned long uptime); 519 static int proc_oom_score(struct task_struct *task, char *buffer) 520 { 521 unsigned long points; 522 struct timespec uptime; 523 524 do_posix_clock_monotonic_gettime(&uptime); 525 points = badness(task, uptime.tv_sec); 526 return sprintf(buffer, "%lu\n", points); 527 } 528 529 /************************************************************************/ 530 /* Here the fs part begins */ 531 /************************************************************************/ 532 533 /* permission checks */ 534 535 /* If the process being read is separated by chroot from the reading process, 536 * don't let the reader access the threads. 537 * 538 * note: this does dput(root) and mntput(vfsmnt) on exit. 539 */ 540 static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt) 541 { 542 struct dentry *de, *base; 543 struct vfsmount *our_vfsmnt, *mnt; 544 int res = 0; 545 546 read_lock(¤t->fs->lock); 547 our_vfsmnt = mntget(current->fs->rootmnt); 548 base = dget(current->fs->root); 549 read_unlock(¤t->fs->lock); 550 551 spin_lock(&vfsmount_lock); 552 de = root; 553 mnt = vfsmnt; 554 555 while (mnt != our_vfsmnt) { 556 if (mnt == mnt->mnt_parent) 557 goto out; 558 de = mnt->mnt_mountpoint; 559 mnt = mnt->mnt_parent; 560 } 561 562 if (!is_subdir(de, base)) 563 goto out; 564 spin_unlock(&vfsmount_lock); 565 566 exit: 567 dput(base); 568 mntput(our_vfsmnt); 569 dput(root); 570 mntput(vfsmnt); 571 return res; 572 out: 573 spin_unlock(&vfsmount_lock); 574 res = -EACCES; 575 goto exit; 576 } 577 578 static int proc_check_root(struct inode *inode) 579 { 580 struct dentry *root; 581 struct vfsmount *vfsmnt; 582 583 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */ 584 return -ENOENT; 585 return proc_check_chroot(root, vfsmnt); 586 } 587 588 static int proc_permission(struct inode *inode, int mask, struct nameidata *nd) 589 { 590 if (generic_permission(inode, mask, NULL) != 0) 591 return -EACCES; 592 return proc_check_root(inode); 593 } 594 595 static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd) 596 { 597 struct dentry *root; 598 struct vfsmount *vfsmnt; 599 600 if (generic_permission(inode, mask, NULL) != 0) 601 return -EACCES; 602 603 if (proc_task_root_link(inode, &root, &vfsmnt)) 604 return -ENOENT; 605 606 return proc_check_chroot(root, vfsmnt); 607 } 608 609 extern struct seq_operations proc_pid_maps_op; 610 static int maps_open(struct inode *inode, struct file *file) 611 { 612 struct task_struct *task = proc_task(inode); 613 int ret = seq_open(file, &proc_pid_maps_op); 614 if (!ret) { 615 struct seq_file *m = file->private_data; 616 m->private = task; 617 } 618 return ret; 619 } 620 621 static struct file_operations proc_maps_operations = { 622 .open = maps_open, 623 .read = seq_read, 624 .llseek = seq_lseek, 625 .release = seq_release, 626 }; 627 628 #ifdef CONFIG_NUMA 629 extern struct seq_operations proc_pid_numa_maps_op; 630 static int numa_maps_open(struct inode *inode, struct file *file) 631 { 632 struct task_struct *task = proc_task(inode); 633 int ret = seq_open(file, &proc_pid_numa_maps_op); 634 if (!ret) { 635 struct seq_file *m = file->private_data; 636 m->private = task; 637 } 638 return ret; 639 } 640 641 static struct file_operations proc_numa_maps_operations = { 642 .open = numa_maps_open, 643 .read = seq_read, 644 .llseek = seq_lseek, 645 .release = seq_release, 646 }; 647 #endif 648 649 #ifdef CONFIG_MMU 650 extern struct seq_operations proc_pid_smaps_op; 651 static int smaps_open(struct inode *inode, struct file *file) 652 { 653 struct task_struct *task = proc_task(inode); 654 int ret = seq_open(file, &proc_pid_smaps_op); 655 if (!ret) { 656 struct seq_file *m = file->private_data; 657 m->private = task; 658 } 659 return ret; 660 } 661 662 static struct file_operations proc_smaps_operations = { 663 .open = smaps_open, 664 .read = seq_read, 665 .llseek = seq_lseek, 666 .release = seq_release, 667 }; 668 #endif 669 670 extern struct seq_operations mounts_op; 671 struct proc_mounts { 672 struct seq_file m; 673 int event; 674 }; 675 676 static int mounts_open(struct inode *inode, struct file *file) 677 { 678 struct task_struct *task = proc_task(inode); 679 struct namespace *namespace; 680 struct proc_mounts *p; 681 int ret = -EINVAL; 682 683 task_lock(task); 684 namespace = task->namespace; 685 if (namespace) 686 get_namespace(namespace); 687 task_unlock(task); 688 689 if (namespace) { 690 ret = -ENOMEM; 691 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 692 if (p) { 693 file->private_data = &p->m; 694 ret = seq_open(file, &mounts_op); 695 if (!ret) { 696 p->m.private = namespace; 697 p->event = namespace->event; 698 return 0; 699 } 700 kfree(p); 701 } 702 put_namespace(namespace); 703 } 704 return ret; 705 } 706 707 static int mounts_release(struct inode *inode, struct file *file) 708 { 709 struct seq_file *m = file->private_data; 710 struct namespace *namespace = m->private; 711 put_namespace(namespace); 712 return seq_release(inode, file); 713 } 714 715 static unsigned mounts_poll(struct file *file, poll_table *wait) 716 { 717 struct proc_mounts *p = file->private_data; 718 struct namespace *ns = p->m.private; 719 unsigned res = 0; 720 721 poll_wait(file, &ns->poll, wait); 722 723 spin_lock(&vfsmount_lock); 724 if (p->event != ns->event) { 725 p->event = ns->event; 726 res = POLLERR; 727 } 728 spin_unlock(&vfsmount_lock); 729 730 return res; 731 } 732 733 static struct file_operations proc_mounts_operations = { 734 .open = mounts_open, 735 .read = seq_read, 736 .llseek = seq_lseek, 737 .release = mounts_release, 738 .poll = mounts_poll, 739 }; 740 741 extern struct seq_operations mountstats_op; 742 static int mountstats_open(struct inode *inode, struct file *file) 743 { 744 struct task_struct *task = proc_task(inode); 745 int ret = seq_open(file, &mountstats_op); 746 747 if (!ret) { 748 struct seq_file *m = file->private_data; 749 struct namespace *namespace; 750 task_lock(task); 751 namespace = task->namespace; 752 if (namespace) 753 get_namespace(namespace); 754 task_unlock(task); 755 756 if (namespace) 757 m->private = namespace; 758 else { 759 seq_release(inode, file); 760 ret = -EINVAL; 761 } 762 } 763 return ret; 764 } 765 766 static struct file_operations proc_mountstats_operations = { 767 .open = mountstats_open, 768 .read = seq_read, 769 .llseek = seq_lseek, 770 .release = mounts_release, 771 }; 772 773 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 774 775 static ssize_t proc_info_read(struct file * file, char __user * buf, 776 size_t count, loff_t *ppos) 777 { 778 struct inode * inode = file->f_dentry->d_inode; 779 unsigned long page; 780 ssize_t length; 781 struct task_struct *task = proc_task(inode); 782 783 if (count > PROC_BLOCK_SIZE) 784 count = PROC_BLOCK_SIZE; 785 if (!(page = __get_free_page(GFP_KERNEL))) 786 return -ENOMEM; 787 788 length = PROC_I(inode)->op.proc_read(task, (char*)page); 789 790 if (length >= 0) 791 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 792 free_page(page); 793 return length; 794 } 795 796 static struct file_operations proc_info_file_operations = { 797 .read = proc_info_read, 798 }; 799 800 static int mem_open(struct inode* inode, struct file* file) 801 { 802 file->private_data = (void*)((long)current->self_exec_id); 803 return 0; 804 } 805 806 static ssize_t mem_read(struct file * file, char __user * buf, 807 size_t count, loff_t *ppos) 808 { 809 struct task_struct *task = proc_task(file->f_dentry->d_inode); 810 char *page; 811 unsigned long src = *ppos; 812 int ret = -ESRCH; 813 struct mm_struct *mm; 814 815 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 816 goto out; 817 818 ret = -ENOMEM; 819 page = (char *)__get_free_page(GFP_USER); 820 if (!page) 821 goto out; 822 823 ret = 0; 824 825 mm = get_task_mm(task); 826 if (!mm) 827 goto out_free; 828 829 ret = -EIO; 830 831 if (file->private_data != (void*)((long)current->self_exec_id)) 832 goto out_put; 833 834 ret = 0; 835 836 while (count > 0) { 837 int this_len, retval; 838 839 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 840 retval = access_process_vm(task, src, page, this_len, 0); 841 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { 842 if (!ret) 843 ret = -EIO; 844 break; 845 } 846 847 if (copy_to_user(buf, page, retval)) { 848 ret = -EFAULT; 849 break; 850 } 851 852 ret += retval; 853 src += retval; 854 buf += retval; 855 count -= retval; 856 } 857 *ppos = src; 858 859 out_put: 860 mmput(mm); 861 out_free: 862 free_page((unsigned long) page); 863 out: 864 return ret; 865 } 866 867 #define mem_write NULL 868 869 #ifndef mem_write 870 /* This is a security hazard */ 871 static ssize_t mem_write(struct file * file, const char * buf, 872 size_t count, loff_t *ppos) 873 { 874 int copied = 0; 875 char *page; 876 struct task_struct *task = proc_task(file->f_dentry->d_inode); 877 unsigned long dst = *ppos; 878 879 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 880 return -ESRCH; 881 882 page = (char *)__get_free_page(GFP_USER); 883 if (!page) 884 return -ENOMEM; 885 886 while (count > 0) { 887 int this_len, retval; 888 889 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 890 if (copy_from_user(page, buf, this_len)) { 891 copied = -EFAULT; 892 break; 893 } 894 retval = access_process_vm(task, dst, page, this_len, 1); 895 if (!retval) { 896 if (!copied) 897 copied = -EIO; 898 break; 899 } 900 copied += retval; 901 buf += retval; 902 dst += retval; 903 count -= retval; 904 } 905 *ppos = dst; 906 free_page((unsigned long) page); 907 return copied; 908 } 909 #endif 910 911 static loff_t mem_lseek(struct file * file, loff_t offset, int orig) 912 { 913 switch (orig) { 914 case 0: 915 file->f_pos = offset; 916 break; 917 case 1: 918 file->f_pos += offset; 919 break; 920 default: 921 return -EINVAL; 922 } 923 force_successful_syscall_return(); 924 return file->f_pos; 925 } 926 927 static struct file_operations proc_mem_operations = { 928 .llseek = mem_lseek, 929 .read = mem_read, 930 .write = mem_write, 931 .open = mem_open, 932 }; 933 934 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 935 size_t count, loff_t *ppos) 936 { 937 struct task_struct *task = proc_task(file->f_dentry->d_inode); 938 char buffer[8]; 939 size_t len; 940 int oom_adjust = task->oomkilladj; 941 loff_t __ppos = *ppos; 942 943 len = sprintf(buffer, "%i\n", oom_adjust); 944 if (__ppos >= len) 945 return 0; 946 if (count > len-__ppos) 947 count = len-__ppos; 948 if (copy_to_user(buf, buffer + __ppos, count)) 949 return -EFAULT; 950 *ppos = __ppos + count; 951 return count; 952 } 953 954 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 955 size_t count, loff_t *ppos) 956 { 957 struct task_struct *task = proc_task(file->f_dentry->d_inode); 958 char buffer[8], *end; 959 int oom_adjust; 960 961 if (!capable(CAP_SYS_RESOURCE)) 962 return -EPERM; 963 memset(buffer, 0, 8); 964 if (count > 6) 965 count = 6; 966 if (copy_from_user(buffer, buf, count)) 967 return -EFAULT; 968 oom_adjust = simple_strtol(buffer, &end, 0); 969 if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE) 970 return -EINVAL; 971 if (*end == '\n') 972 end++; 973 task->oomkilladj = oom_adjust; 974 if (end - buffer == 0) 975 return -EIO; 976 return end - buffer; 977 } 978 979 static struct file_operations proc_oom_adjust_operations = { 980 .read = oom_adjust_read, 981 .write = oom_adjust_write, 982 }; 983 984 static struct inode_operations proc_mem_inode_operations = { 985 .permission = proc_permission, 986 }; 987 988 #ifdef CONFIG_AUDITSYSCALL 989 #define TMPBUFLEN 21 990 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 991 size_t count, loff_t *ppos) 992 { 993 struct inode * inode = file->f_dentry->d_inode; 994 struct task_struct *task = proc_task(inode); 995 ssize_t length; 996 char tmpbuf[TMPBUFLEN]; 997 998 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 999 audit_get_loginuid(task->audit_context)); 1000 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1001 } 1002 1003 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1004 size_t count, loff_t *ppos) 1005 { 1006 struct inode * inode = file->f_dentry->d_inode; 1007 char *page, *tmp; 1008 ssize_t length; 1009 struct task_struct *task = proc_task(inode); 1010 uid_t loginuid; 1011 1012 if (!capable(CAP_AUDIT_CONTROL)) 1013 return -EPERM; 1014 1015 if (current != task) 1016 return -EPERM; 1017 1018 if (count > PAGE_SIZE) 1019 count = PAGE_SIZE; 1020 1021 if (*ppos != 0) { 1022 /* No partial writes. */ 1023 return -EINVAL; 1024 } 1025 page = (char*)__get_free_page(GFP_USER); 1026 if (!page) 1027 return -ENOMEM; 1028 length = -EFAULT; 1029 if (copy_from_user(page, buf, count)) 1030 goto out_free_page; 1031 1032 loginuid = simple_strtoul(page, &tmp, 10); 1033 if (tmp == page) { 1034 length = -EINVAL; 1035 goto out_free_page; 1036 1037 } 1038 length = audit_set_loginuid(task, loginuid); 1039 if (likely(length == 0)) 1040 length = count; 1041 1042 out_free_page: 1043 free_page((unsigned long) page); 1044 return length; 1045 } 1046 1047 static struct file_operations proc_loginuid_operations = { 1048 .read = proc_loginuid_read, 1049 .write = proc_loginuid_write, 1050 }; 1051 #endif 1052 1053 #ifdef CONFIG_SECCOMP 1054 static ssize_t seccomp_read(struct file *file, char __user *buf, 1055 size_t count, loff_t *ppos) 1056 { 1057 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1058 char __buf[20]; 1059 loff_t __ppos = *ppos; 1060 size_t len; 1061 1062 /* no need to print the trailing zero, so use only len */ 1063 len = sprintf(__buf, "%u\n", tsk->seccomp.mode); 1064 if (__ppos >= len) 1065 return 0; 1066 if (count > len - __ppos) 1067 count = len - __ppos; 1068 if (copy_to_user(buf, __buf + __ppos, count)) 1069 return -EFAULT; 1070 *ppos = __ppos + count; 1071 return count; 1072 } 1073 1074 static ssize_t seccomp_write(struct file *file, const char __user *buf, 1075 size_t count, loff_t *ppos) 1076 { 1077 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1078 char __buf[20], *end; 1079 unsigned int seccomp_mode; 1080 1081 /* can set it only once to be even more secure */ 1082 if (unlikely(tsk->seccomp.mode)) 1083 return -EPERM; 1084 1085 memset(__buf, 0, sizeof(__buf)); 1086 count = min(count, sizeof(__buf) - 1); 1087 if (copy_from_user(__buf, buf, count)) 1088 return -EFAULT; 1089 seccomp_mode = simple_strtoul(__buf, &end, 0); 1090 if (*end == '\n') 1091 end++; 1092 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { 1093 tsk->seccomp.mode = seccomp_mode; 1094 set_tsk_thread_flag(tsk, TIF_SECCOMP); 1095 } else 1096 return -EINVAL; 1097 if (unlikely(!(end - __buf))) 1098 return -EIO; 1099 return end - __buf; 1100 } 1101 1102 static struct file_operations proc_seccomp_operations = { 1103 .read = seccomp_read, 1104 .write = seccomp_write, 1105 }; 1106 #endif /* CONFIG_SECCOMP */ 1107 1108 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1109 { 1110 struct inode *inode = dentry->d_inode; 1111 int error = -EACCES; 1112 1113 /* We don't need a base pointer in the /proc filesystem */ 1114 path_release(nd); 1115 1116 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1117 goto out; 1118 error = proc_check_root(inode); 1119 if (error) 1120 goto out; 1121 1122 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); 1123 nd->last_type = LAST_BIND; 1124 out: 1125 return ERR_PTR(error); 1126 } 1127 1128 static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, 1129 char __user *buffer, int buflen) 1130 { 1131 struct inode * inode; 1132 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; 1133 int len; 1134 1135 if (!tmp) 1136 return -ENOMEM; 1137 1138 inode = dentry->d_inode; 1139 path = d_path(dentry, mnt, tmp, PAGE_SIZE); 1140 len = PTR_ERR(path); 1141 if (IS_ERR(path)) 1142 goto out; 1143 len = tmp + PAGE_SIZE - 1 - path; 1144 1145 if (len > buflen) 1146 len = buflen; 1147 if (copy_to_user(buffer, path, len)) 1148 len = -EFAULT; 1149 out: 1150 free_page((unsigned long)tmp); 1151 return len; 1152 } 1153 1154 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1155 { 1156 int error = -EACCES; 1157 struct inode *inode = dentry->d_inode; 1158 struct dentry *de; 1159 struct vfsmount *mnt = NULL; 1160 1161 lock_kernel(); 1162 1163 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1164 goto out; 1165 error = proc_check_root(inode); 1166 if (error) 1167 goto out; 1168 1169 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); 1170 if (error) 1171 goto out; 1172 1173 error = do_proc_readlink(de, mnt, buffer, buflen); 1174 dput(de); 1175 mntput(mnt); 1176 out: 1177 unlock_kernel(); 1178 return error; 1179 } 1180 1181 static struct inode_operations proc_pid_link_inode_operations = { 1182 .readlink = proc_pid_readlink, 1183 .follow_link = proc_pid_follow_link 1184 }; 1185 1186 #define NUMBUF 10 1187 1188 static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) 1189 { 1190 struct inode *inode = filp->f_dentry->d_inode; 1191 struct task_struct *p = proc_task(inode); 1192 unsigned int fd, tid, ino; 1193 int retval; 1194 char buf[NUMBUF]; 1195 struct files_struct * files; 1196 struct fdtable *fdt; 1197 1198 retval = -ENOENT; 1199 if (!pid_alive(p)) 1200 goto out; 1201 retval = 0; 1202 tid = p->pid; 1203 1204 fd = filp->f_pos; 1205 switch (fd) { 1206 case 0: 1207 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1208 goto out; 1209 filp->f_pos++; 1210 case 1: 1211 ino = fake_ino(tid, PROC_TID_INO); 1212 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1213 goto out; 1214 filp->f_pos++; 1215 default: 1216 files = get_files_struct(p); 1217 if (!files) 1218 goto out; 1219 rcu_read_lock(); 1220 fdt = files_fdtable(files); 1221 for (fd = filp->f_pos-2; 1222 fd < fdt->max_fds; 1223 fd++, filp->f_pos++) { 1224 unsigned int i,j; 1225 1226 if (!fcheck_files(files, fd)) 1227 continue; 1228 rcu_read_unlock(); 1229 1230 j = NUMBUF; 1231 i = fd; 1232 do { 1233 j--; 1234 buf[j] = '0' + (i % 10); 1235 i /= 10; 1236 } while (i); 1237 1238 ino = fake_ino(tid, PROC_TID_FD_DIR + fd); 1239 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) { 1240 rcu_read_lock(); 1241 break; 1242 } 1243 rcu_read_lock(); 1244 } 1245 rcu_read_unlock(); 1246 put_files_struct(files); 1247 } 1248 out: 1249 return retval; 1250 } 1251 1252 static int proc_pident_readdir(struct file *filp, 1253 void *dirent, filldir_t filldir, 1254 struct pid_entry *ents, unsigned int nents) 1255 { 1256 int i; 1257 int pid; 1258 struct dentry *dentry = filp->f_dentry; 1259 struct inode *inode = dentry->d_inode; 1260 struct pid_entry *p; 1261 ino_t ino; 1262 int ret; 1263 1264 ret = -ENOENT; 1265 if (!pid_alive(proc_task(inode))) 1266 goto out; 1267 1268 ret = 0; 1269 pid = proc_task(inode)->pid; 1270 i = filp->f_pos; 1271 switch (i) { 1272 case 0: 1273 ino = inode->i_ino; 1274 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 1275 goto out; 1276 i++; 1277 filp->f_pos++; 1278 /* fall through */ 1279 case 1: 1280 ino = parent_ino(dentry); 1281 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1282 goto out; 1283 i++; 1284 filp->f_pos++; 1285 /* fall through */ 1286 default: 1287 i -= 2; 1288 if (i >= nents) { 1289 ret = 1; 1290 goto out; 1291 } 1292 p = ents + i; 1293 while (p->name) { 1294 if (filldir(dirent, p->name, p->len, filp->f_pos, 1295 fake_ino(pid, p->type), p->mode >> 12) < 0) 1296 goto out; 1297 filp->f_pos++; 1298 p++; 1299 } 1300 } 1301 1302 ret = 1; 1303 out: 1304 return ret; 1305 } 1306 1307 static int proc_tgid_base_readdir(struct file * filp, 1308 void * dirent, filldir_t filldir) 1309 { 1310 return proc_pident_readdir(filp,dirent,filldir, 1311 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 1312 } 1313 1314 static int proc_tid_base_readdir(struct file * filp, 1315 void * dirent, filldir_t filldir) 1316 { 1317 return proc_pident_readdir(filp,dirent,filldir, 1318 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 1319 } 1320 1321 /* building an inode */ 1322 1323 static int task_dumpable(struct task_struct *task) 1324 { 1325 int dumpable = 0; 1326 struct mm_struct *mm; 1327 1328 task_lock(task); 1329 mm = task->mm; 1330 if (mm) 1331 dumpable = mm->dumpable; 1332 task_unlock(task); 1333 if(dumpable == 1) 1334 return 1; 1335 return 0; 1336 } 1337 1338 1339 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino) 1340 { 1341 struct inode * inode; 1342 struct proc_inode *ei; 1343 1344 /* We need a new inode */ 1345 1346 inode = new_inode(sb); 1347 if (!inode) 1348 goto out; 1349 1350 /* Common stuff */ 1351 ei = PROC_I(inode); 1352 ei->task = NULL; 1353 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1354 inode->i_ino = fake_ino(task->pid, ino); 1355 1356 if (!pid_alive(task)) 1357 goto out_unlock; 1358 1359 /* 1360 * grab the reference to task. 1361 */ 1362 get_task_struct(task); 1363 ei->task = task; 1364 ei->type = ino; 1365 inode->i_uid = 0; 1366 inode->i_gid = 0; 1367 if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) { 1368 inode->i_uid = task->euid; 1369 inode->i_gid = task->egid; 1370 } 1371 security_task_to_inode(task, inode); 1372 1373 out: 1374 return inode; 1375 1376 out_unlock: 1377 ei->pde = NULL; 1378 iput(inode); 1379 return NULL; 1380 } 1381 1382 /* dentry stuff */ 1383 1384 /* 1385 * Exceptional case: normally we are not allowed to unhash a busy 1386 * directory. In this case, however, we can do it - no aliasing problems 1387 * due to the way we treat inodes. 1388 * 1389 * Rewrite the inode's ownerships here because the owning task may have 1390 * performed a setuid(), etc. 1391 */ 1392 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1393 { 1394 struct inode *inode = dentry->d_inode; 1395 struct task_struct *task = proc_task(inode); 1396 if (pid_alive(task)) { 1397 if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) { 1398 inode->i_uid = task->euid; 1399 inode->i_gid = task->egid; 1400 } else { 1401 inode->i_uid = 0; 1402 inode->i_gid = 0; 1403 } 1404 security_task_to_inode(task, inode); 1405 return 1; 1406 } 1407 d_drop(dentry); 1408 return 0; 1409 } 1410 1411 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1412 { 1413 struct inode *inode = dentry->d_inode; 1414 struct task_struct *task = proc_task(inode); 1415 int fd = proc_type(inode) - PROC_TID_FD_DIR; 1416 struct files_struct *files; 1417 1418 files = get_files_struct(task); 1419 if (files) { 1420 rcu_read_lock(); 1421 if (fcheck_files(files, fd)) { 1422 rcu_read_unlock(); 1423 put_files_struct(files); 1424 if (task_dumpable(task)) { 1425 inode->i_uid = task->euid; 1426 inode->i_gid = task->egid; 1427 } else { 1428 inode->i_uid = 0; 1429 inode->i_gid = 0; 1430 } 1431 security_task_to_inode(task, inode); 1432 return 1; 1433 } 1434 rcu_read_unlock(); 1435 put_files_struct(files); 1436 } 1437 d_drop(dentry); 1438 return 0; 1439 } 1440 1441 static void pid_base_iput(struct dentry *dentry, struct inode *inode) 1442 { 1443 struct task_struct *task = proc_task(inode); 1444 spin_lock(&task->proc_lock); 1445 if (task->proc_dentry == dentry) 1446 task->proc_dentry = NULL; 1447 spin_unlock(&task->proc_lock); 1448 iput(inode); 1449 } 1450 1451 static int pid_delete_dentry(struct dentry * dentry) 1452 { 1453 /* Is the task we represent dead? 1454 * If so, then don't put the dentry on the lru list, 1455 * kill it immediately. 1456 */ 1457 return !pid_alive(proc_task(dentry->d_inode)); 1458 } 1459 1460 static struct dentry_operations tid_fd_dentry_operations = 1461 { 1462 .d_revalidate = tid_fd_revalidate, 1463 .d_delete = pid_delete_dentry, 1464 }; 1465 1466 static struct dentry_operations pid_dentry_operations = 1467 { 1468 .d_revalidate = pid_revalidate, 1469 .d_delete = pid_delete_dentry, 1470 }; 1471 1472 static struct dentry_operations pid_base_dentry_operations = 1473 { 1474 .d_revalidate = pid_revalidate, 1475 .d_iput = pid_base_iput, 1476 .d_delete = pid_delete_dentry, 1477 }; 1478 1479 /* Lookups */ 1480 1481 static unsigned name_to_int(struct dentry *dentry) 1482 { 1483 const char *name = dentry->d_name.name; 1484 int len = dentry->d_name.len; 1485 unsigned n = 0; 1486 1487 if (len > 1 && *name == '0') 1488 goto out; 1489 while (len-- > 0) { 1490 unsigned c = *name++ - '0'; 1491 if (c > 9) 1492 goto out; 1493 if (n >= (~0U-9)/10) 1494 goto out; 1495 n *= 10; 1496 n += c; 1497 } 1498 return n; 1499 out: 1500 return ~0U; 1501 } 1502 1503 /* SMP-safe */ 1504 static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) 1505 { 1506 struct task_struct *task = proc_task(dir); 1507 unsigned fd = name_to_int(dentry); 1508 struct file * file; 1509 struct files_struct * files; 1510 struct inode *inode; 1511 struct proc_inode *ei; 1512 1513 if (fd == ~0U) 1514 goto out; 1515 if (!pid_alive(task)) 1516 goto out; 1517 1518 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd); 1519 if (!inode) 1520 goto out; 1521 ei = PROC_I(inode); 1522 files = get_files_struct(task); 1523 if (!files) 1524 goto out_unlock; 1525 inode->i_mode = S_IFLNK; 1526 rcu_read_lock(); 1527 file = fcheck_files(files, fd); 1528 if (!file) 1529 goto out_unlock2; 1530 if (file->f_mode & 1) 1531 inode->i_mode |= S_IRUSR | S_IXUSR; 1532 if (file->f_mode & 2) 1533 inode->i_mode |= S_IWUSR | S_IXUSR; 1534 rcu_read_unlock(); 1535 put_files_struct(files); 1536 inode->i_op = &proc_pid_link_inode_operations; 1537 inode->i_size = 64; 1538 ei->op.proc_get_link = proc_fd_link; 1539 dentry->d_op = &tid_fd_dentry_operations; 1540 d_add(dentry, inode); 1541 return NULL; 1542 1543 out_unlock2: 1544 rcu_read_unlock(); 1545 put_files_struct(files); 1546 out_unlock: 1547 iput(inode); 1548 out: 1549 return ERR_PTR(-ENOENT); 1550 } 1551 1552 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); 1553 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); 1554 1555 static struct file_operations proc_fd_operations = { 1556 .read = generic_read_dir, 1557 .readdir = proc_readfd, 1558 }; 1559 1560 static struct file_operations proc_task_operations = { 1561 .read = generic_read_dir, 1562 .readdir = proc_task_readdir, 1563 }; 1564 1565 /* 1566 * proc directories can do almost nothing.. 1567 */ 1568 static struct inode_operations proc_fd_inode_operations = { 1569 .lookup = proc_lookupfd, 1570 .permission = proc_permission, 1571 }; 1572 1573 static struct inode_operations proc_task_inode_operations = { 1574 .lookup = proc_task_lookup, 1575 .permission = proc_task_permission, 1576 }; 1577 1578 #ifdef CONFIG_SECURITY 1579 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 1580 size_t count, loff_t *ppos) 1581 { 1582 struct inode * inode = file->f_dentry->d_inode; 1583 unsigned long page; 1584 ssize_t length; 1585 struct task_struct *task = proc_task(inode); 1586 1587 if (count > PAGE_SIZE) 1588 count = PAGE_SIZE; 1589 if (!(page = __get_free_page(GFP_KERNEL))) 1590 return -ENOMEM; 1591 1592 length = security_getprocattr(task, 1593 (char*)file->f_dentry->d_name.name, 1594 (void*)page, count); 1595 if (length >= 0) 1596 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 1597 free_page(page); 1598 return length; 1599 } 1600 1601 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 1602 size_t count, loff_t *ppos) 1603 { 1604 struct inode * inode = file->f_dentry->d_inode; 1605 char *page; 1606 ssize_t length; 1607 struct task_struct *task = proc_task(inode); 1608 1609 if (count > PAGE_SIZE) 1610 count = PAGE_SIZE; 1611 if (*ppos != 0) { 1612 /* No partial writes. */ 1613 return -EINVAL; 1614 } 1615 page = (char*)__get_free_page(GFP_USER); 1616 if (!page) 1617 return -ENOMEM; 1618 length = -EFAULT; 1619 if (copy_from_user(page, buf, count)) 1620 goto out; 1621 1622 length = security_setprocattr(task, 1623 (char*)file->f_dentry->d_name.name, 1624 (void*)page, count); 1625 out: 1626 free_page((unsigned long) page); 1627 return length; 1628 } 1629 1630 static struct file_operations proc_pid_attr_operations = { 1631 .read = proc_pid_attr_read, 1632 .write = proc_pid_attr_write, 1633 }; 1634 1635 static struct file_operations proc_tid_attr_operations; 1636 static struct inode_operations proc_tid_attr_inode_operations; 1637 static struct file_operations proc_tgid_attr_operations; 1638 static struct inode_operations proc_tgid_attr_inode_operations; 1639 #endif 1640 1641 static int get_tid_list(int index, unsigned int *tids, struct inode *dir); 1642 1643 /* SMP-safe */ 1644 static struct dentry *proc_pident_lookup(struct inode *dir, 1645 struct dentry *dentry, 1646 struct pid_entry *ents) 1647 { 1648 struct inode *inode; 1649 int error; 1650 struct task_struct *task = proc_task(dir); 1651 struct pid_entry *p; 1652 struct proc_inode *ei; 1653 1654 error = -ENOENT; 1655 inode = NULL; 1656 1657 if (!pid_alive(task)) 1658 goto out; 1659 1660 for (p = ents; p->name; p++) { 1661 if (p->len != dentry->d_name.len) 1662 continue; 1663 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1664 break; 1665 } 1666 if (!p->name) 1667 goto out; 1668 1669 error = -EINVAL; 1670 inode = proc_pid_make_inode(dir->i_sb, task, p->type); 1671 if (!inode) 1672 goto out; 1673 1674 ei = PROC_I(inode); 1675 inode->i_mode = p->mode; 1676 /* 1677 * Yes, it does not scale. And it should not. Don't add 1678 * new entries into /proc/<tgid>/ without very good reasons. 1679 */ 1680 switch(p->type) { 1681 case PROC_TGID_TASK: 1682 inode->i_nlink = 2 + get_tid_list(2, NULL, dir); 1683 inode->i_op = &proc_task_inode_operations; 1684 inode->i_fop = &proc_task_operations; 1685 break; 1686 case PROC_TID_FD: 1687 case PROC_TGID_FD: 1688 inode->i_nlink = 2; 1689 inode->i_op = &proc_fd_inode_operations; 1690 inode->i_fop = &proc_fd_operations; 1691 break; 1692 case PROC_TID_EXE: 1693 case PROC_TGID_EXE: 1694 inode->i_op = &proc_pid_link_inode_operations; 1695 ei->op.proc_get_link = proc_exe_link; 1696 break; 1697 case PROC_TID_CWD: 1698 case PROC_TGID_CWD: 1699 inode->i_op = &proc_pid_link_inode_operations; 1700 ei->op.proc_get_link = proc_cwd_link; 1701 break; 1702 case PROC_TID_ROOT: 1703 case PROC_TGID_ROOT: 1704 inode->i_op = &proc_pid_link_inode_operations; 1705 ei->op.proc_get_link = proc_root_link; 1706 break; 1707 case PROC_TID_ENVIRON: 1708 case PROC_TGID_ENVIRON: 1709 inode->i_fop = &proc_info_file_operations; 1710 ei->op.proc_read = proc_pid_environ; 1711 break; 1712 case PROC_TID_AUXV: 1713 case PROC_TGID_AUXV: 1714 inode->i_fop = &proc_info_file_operations; 1715 ei->op.proc_read = proc_pid_auxv; 1716 break; 1717 case PROC_TID_STATUS: 1718 case PROC_TGID_STATUS: 1719 inode->i_fop = &proc_info_file_operations; 1720 ei->op.proc_read = proc_pid_status; 1721 break; 1722 case PROC_TID_STAT: 1723 inode->i_fop = &proc_info_file_operations; 1724 ei->op.proc_read = proc_tid_stat; 1725 break; 1726 case PROC_TGID_STAT: 1727 inode->i_fop = &proc_info_file_operations; 1728 ei->op.proc_read = proc_tgid_stat; 1729 break; 1730 case PROC_TID_CMDLINE: 1731 case PROC_TGID_CMDLINE: 1732 inode->i_fop = &proc_info_file_operations; 1733 ei->op.proc_read = proc_pid_cmdline; 1734 break; 1735 case PROC_TID_STATM: 1736 case PROC_TGID_STATM: 1737 inode->i_fop = &proc_info_file_operations; 1738 ei->op.proc_read = proc_pid_statm; 1739 break; 1740 case PROC_TID_MAPS: 1741 case PROC_TGID_MAPS: 1742 inode->i_fop = &proc_maps_operations; 1743 break; 1744 #ifdef CONFIG_NUMA 1745 case PROC_TID_NUMA_MAPS: 1746 case PROC_TGID_NUMA_MAPS: 1747 inode->i_fop = &proc_numa_maps_operations; 1748 break; 1749 #endif 1750 case PROC_TID_MEM: 1751 case PROC_TGID_MEM: 1752 inode->i_op = &proc_mem_inode_operations; 1753 inode->i_fop = &proc_mem_operations; 1754 break; 1755 #ifdef CONFIG_SECCOMP 1756 case PROC_TID_SECCOMP: 1757 case PROC_TGID_SECCOMP: 1758 inode->i_fop = &proc_seccomp_operations; 1759 break; 1760 #endif /* CONFIG_SECCOMP */ 1761 case PROC_TID_MOUNTS: 1762 case PROC_TGID_MOUNTS: 1763 inode->i_fop = &proc_mounts_operations; 1764 break; 1765 #ifdef CONFIG_MMU 1766 case PROC_TID_SMAPS: 1767 case PROC_TGID_SMAPS: 1768 inode->i_fop = &proc_smaps_operations; 1769 break; 1770 #endif 1771 case PROC_TID_MOUNTSTATS: 1772 case PROC_TGID_MOUNTSTATS: 1773 inode->i_fop = &proc_mountstats_operations; 1774 break; 1775 #ifdef CONFIG_SECURITY 1776 case PROC_TID_ATTR: 1777 inode->i_nlink = 2; 1778 inode->i_op = &proc_tid_attr_inode_operations; 1779 inode->i_fop = &proc_tid_attr_operations; 1780 break; 1781 case PROC_TGID_ATTR: 1782 inode->i_nlink = 2; 1783 inode->i_op = &proc_tgid_attr_inode_operations; 1784 inode->i_fop = &proc_tgid_attr_operations; 1785 break; 1786 case PROC_TID_ATTR_CURRENT: 1787 case PROC_TGID_ATTR_CURRENT: 1788 case PROC_TID_ATTR_PREV: 1789 case PROC_TGID_ATTR_PREV: 1790 case PROC_TID_ATTR_EXEC: 1791 case PROC_TGID_ATTR_EXEC: 1792 case PROC_TID_ATTR_FSCREATE: 1793 case PROC_TGID_ATTR_FSCREATE: 1794 inode->i_fop = &proc_pid_attr_operations; 1795 break; 1796 #endif 1797 #ifdef CONFIG_KALLSYMS 1798 case PROC_TID_WCHAN: 1799 case PROC_TGID_WCHAN: 1800 inode->i_fop = &proc_info_file_operations; 1801 ei->op.proc_read = proc_pid_wchan; 1802 break; 1803 #endif 1804 #ifdef CONFIG_SCHEDSTATS 1805 case PROC_TID_SCHEDSTAT: 1806 case PROC_TGID_SCHEDSTAT: 1807 inode->i_fop = &proc_info_file_operations; 1808 ei->op.proc_read = proc_pid_schedstat; 1809 break; 1810 #endif 1811 #ifdef CONFIG_CPUSETS 1812 case PROC_TID_CPUSET: 1813 case PROC_TGID_CPUSET: 1814 inode->i_fop = &proc_cpuset_operations; 1815 break; 1816 #endif 1817 case PROC_TID_OOM_SCORE: 1818 case PROC_TGID_OOM_SCORE: 1819 inode->i_fop = &proc_info_file_operations; 1820 ei->op.proc_read = proc_oom_score; 1821 break; 1822 case PROC_TID_OOM_ADJUST: 1823 case PROC_TGID_OOM_ADJUST: 1824 inode->i_fop = &proc_oom_adjust_operations; 1825 break; 1826 #ifdef CONFIG_AUDITSYSCALL 1827 case PROC_TID_LOGINUID: 1828 case PROC_TGID_LOGINUID: 1829 inode->i_fop = &proc_loginuid_operations; 1830 break; 1831 #endif 1832 default: 1833 printk("procfs: impossible type (%d)",p->type); 1834 iput(inode); 1835 return ERR_PTR(-EINVAL); 1836 } 1837 dentry->d_op = &pid_dentry_operations; 1838 d_add(dentry, inode); 1839 return NULL; 1840 1841 out: 1842 return ERR_PTR(error); 1843 } 1844 1845 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1846 return proc_pident_lookup(dir, dentry, tgid_base_stuff); 1847 } 1848 1849 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1850 return proc_pident_lookup(dir, dentry, tid_base_stuff); 1851 } 1852 1853 static struct file_operations proc_tgid_base_operations = { 1854 .read = generic_read_dir, 1855 .readdir = proc_tgid_base_readdir, 1856 }; 1857 1858 static struct file_operations proc_tid_base_operations = { 1859 .read = generic_read_dir, 1860 .readdir = proc_tid_base_readdir, 1861 }; 1862 1863 static struct inode_operations proc_tgid_base_inode_operations = { 1864 .lookup = proc_tgid_base_lookup, 1865 }; 1866 1867 static struct inode_operations proc_tid_base_inode_operations = { 1868 .lookup = proc_tid_base_lookup, 1869 }; 1870 1871 #ifdef CONFIG_SECURITY 1872 static int proc_tgid_attr_readdir(struct file * filp, 1873 void * dirent, filldir_t filldir) 1874 { 1875 return proc_pident_readdir(filp,dirent,filldir, 1876 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff)); 1877 } 1878 1879 static int proc_tid_attr_readdir(struct file * filp, 1880 void * dirent, filldir_t filldir) 1881 { 1882 return proc_pident_readdir(filp,dirent,filldir, 1883 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff)); 1884 } 1885 1886 static struct file_operations proc_tgid_attr_operations = { 1887 .read = generic_read_dir, 1888 .readdir = proc_tgid_attr_readdir, 1889 }; 1890 1891 static struct file_operations proc_tid_attr_operations = { 1892 .read = generic_read_dir, 1893 .readdir = proc_tid_attr_readdir, 1894 }; 1895 1896 static struct dentry *proc_tgid_attr_lookup(struct inode *dir, 1897 struct dentry *dentry, struct nameidata *nd) 1898 { 1899 return proc_pident_lookup(dir, dentry, tgid_attr_stuff); 1900 } 1901 1902 static struct dentry *proc_tid_attr_lookup(struct inode *dir, 1903 struct dentry *dentry, struct nameidata *nd) 1904 { 1905 return proc_pident_lookup(dir, dentry, tid_attr_stuff); 1906 } 1907 1908 static struct inode_operations proc_tgid_attr_inode_operations = { 1909 .lookup = proc_tgid_attr_lookup, 1910 }; 1911 1912 static struct inode_operations proc_tid_attr_inode_operations = { 1913 .lookup = proc_tid_attr_lookup, 1914 }; 1915 #endif 1916 1917 /* 1918 * /proc/self: 1919 */ 1920 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 1921 int buflen) 1922 { 1923 char tmp[30]; 1924 sprintf(tmp, "%d", current->tgid); 1925 return vfs_readlink(dentry,buffer,buflen,tmp); 1926 } 1927 1928 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 1929 { 1930 char tmp[30]; 1931 sprintf(tmp, "%d", current->tgid); 1932 return ERR_PTR(vfs_follow_link(nd,tmp)); 1933 } 1934 1935 static struct inode_operations proc_self_inode_operations = { 1936 .readlink = proc_self_readlink, 1937 .follow_link = proc_self_follow_link, 1938 }; 1939 1940 /** 1941 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache. 1942 * @p: task that should be flushed. 1943 * 1944 * Drops the /proc/@pid dcache entry from the hash chains. 1945 * 1946 * Dropping /proc/@pid entries and detach_pid must be synchroneous, 1947 * otherwise e.g. /proc/@pid/exe might point to the wrong executable, 1948 * if the pid value is immediately reused. This is enforced by 1949 * - caller must acquire spin_lock(p->proc_lock) 1950 * - must be called before detach_pid() 1951 * - proc_pid_lookup acquires proc_lock, and checks that 1952 * the target is not dead by looking at the attach count 1953 * of PIDTYPE_PID. 1954 */ 1955 1956 struct dentry *proc_pid_unhash(struct task_struct *p) 1957 { 1958 struct dentry *proc_dentry; 1959 1960 proc_dentry = p->proc_dentry; 1961 if (proc_dentry != NULL) { 1962 1963 spin_lock(&dcache_lock); 1964 spin_lock(&proc_dentry->d_lock); 1965 if (!d_unhashed(proc_dentry)) { 1966 dget_locked(proc_dentry); 1967 __d_drop(proc_dentry); 1968 spin_unlock(&proc_dentry->d_lock); 1969 } else { 1970 spin_unlock(&proc_dentry->d_lock); 1971 proc_dentry = NULL; 1972 } 1973 spin_unlock(&dcache_lock); 1974 } 1975 return proc_dentry; 1976 } 1977 1978 /** 1979 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries 1980 * @proc_dentry: directoy to prune. 1981 * 1982 * Shrink the /proc directory that was used by the just killed thread. 1983 */ 1984 1985 void proc_pid_flush(struct dentry *proc_dentry) 1986 { 1987 might_sleep(); 1988 if(proc_dentry != NULL) { 1989 shrink_dcache_parent(proc_dentry); 1990 dput(proc_dentry); 1991 } 1992 } 1993 1994 /* SMP-safe */ 1995 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 1996 { 1997 struct task_struct *task; 1998 struct inode *inode; 1999 struct proc_inode *ei; 2000 unsigned tgid; 2001 int died; 2002 2003 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) { 2004 inode = new_inode(dir->i_sb); 2005 if (!inode) 2006 return ERR_PTR(-ENOMEM); 2007 ei = PROC_I(inode); 2008 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2009 inode->i_ino = fake_ino(0, PROC_TGID_INO); 2010 ei->pde = NULL; 2011 inode->i_mode = S_IFLNK|S_IRWXUGO; 2012 inode->i_uid = inode->i_gid = 0; 2013 inode->i_size = 64; 2014 inode->i_op = &proc_self_inode_operations; 2015 d_add(dentry, inode); 2016 return NULL; 2017 } 2018 tgid = name_to_int(dentry); 2019 if (tgid == ~0U) 2020 goto out; 2021 2022 read_lock(&tasklist_lock); 2023 task = find_task_by_pid(tgid); 2024 if (task) 2025 get_task_struct(task); 2026 read_unlock(&tasklist_lock); 2027 if (!task) 2028 goto out; 2029 2030 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO); 2031 2032 2033 if (!inode) { 2034 put_task_struct(task); 2035 goto out; 2036 } 2037 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2038 inode->i_op = &proc_tgid_base_inode_operations; 2039 inode->i_fop = &proc_tgid_base_operations; 2040 inode->i_flags|=S_IMMUTABLE; 2041 #ifdef CONFIG_SECURITY 2042 inode->i_nlink = 5; 2043 #else 2044 inode->i_nlink = 4; 2045 #endif 2046 2047 dentry->d_op = &pid_base_dentry_operations; 2048 2049 died = 0; 2050 d_add(dentry, inode); 2051 spin_lock(&task->proc_lock); 2052 task->proc_dentry = dentry; 2053 if (!pid_alive(task)) { 2054 dentry = proc_pid_unhash(task); 2055 died = 1; 2056 } 2057 spin_unlock(&task->proc_lock); 2058 2059 put_task_struct(task); 2060 if (died) { 2061 proc_pid_flush(dentry); 2062 goto out; 2063 } 2064 return NULL; 2065 out: 2066 return ERR_PTR(-ENOENT); 2067 } 2068 2069 /* SMP-safe */ 2070 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2071 { 2072 struct task_struct *task; 2073 struct task_struct *leader = proc_task(dir); 2074 struct inode *inode; 2075 unsigned tid; 2076 2077 tid = name_to_int(dentry); 2078 if (tid == ~0U) 2079 goto out; 2080 2081 read_lock(&tasklist_lock); 2082 task = find_task_by_pid(tid); 2083 if (task) 2084 get_task_struct(task); 2085 read_unlock(&tasklist_lock); 2086 if (!task) 2087 goto out; 2088 if (leader->tgid != task->tgid) 2089 goto out_drop_task; 2090 2091 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO); 2092 2093 2094 if (!inode) 2095 goto out_drop_task; 2096 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2097 inode->i_op = &proc_tid_base_inode_operations; 2098 inode->i_fop = &proc_tid_base_operations; 2099 inode->i_flags|=S_IMMUTABLE; 2100 #ifdef CONFIG_SECURITY 2101 inode->i_nlink = 4; 2102 #else 2103 inode->i_nlink = 3; 2104 #endif 2105 2106 dentry->d_op = &pid_base_dentry_operations; 2107 2108 d_add(dentry, inode); 2109 2110 put_task_struct(task); 2111 return NULL; 2112 out_drop_task: 2113 put_task_struct(task); 2114 out: 2115 return ERR_PTR(-ENOENT); 2116 } 2117 2118 #define PROC_NUMBUF 10 2119 #define PROC_MAXPIDS 20 2120 2121 /* 2122 * Get a few tgid's to return for filldir - we need to hold the 2123 * tasklist lock while doing this, and we must release it before 2124 * we actually do the filldir itself, so we use a temp buffer.. 2125 */ 2126 static int get_tgid_list(int index, unsigned long version, unsigned int *tgids) 2127 { 2128 struct task_struct *p; 2129 int nr_tgids = 0; 2130 2131 index--; 2132 read_lock(&tasklist_lock); 2133 p = NULL; 2134 if (version) { 2135 p = find_task_by_pid(version); 2136 if (p && !thread_group_leader(p)) 2137 p = NULL; 2138 } 2139 2140 if (p) 2141 index = 0; 2142 else 2143 p = next_task(&init_task); 2144 2145 for ( ; p != &init_task; p = next_task(p)) { 2146 int tgid = p->pid; 2147 if (!pid_alive(p)) 2148 continue; 2149 if (--index >= 0) 2150 continue; 2151 tgids[nr_tgids] = tgid; 2152 nr_tgids++; 2153 if (nr_tgids >= PROC_MAXPIDS) 2154 break; 2155 } 2156 read_unlock(&tasklist_lock); 2157 return nr_tgids; 2158 } 2159 2160 /* 2161 * Get a few tid's to return for filldir - we need to hold the 2162 * tasklist lock while doing this, and we must release it before 2163 * we actually do the filldir itself, so we use a temp buffer.. 2164 */ 2165 static int get_tid_list(int index, unsigned int *tids, struct inode *dir) 2166 { 2167 struct task_struct *leader_task = proc_task(dir); 2168 struct task_struct *task = leader_task; 2169 int nr_tids = 0; 2170 2171 index -= 2; 2172 read_lock(&tasklist_lock); 2173 /* 2174 * The starting point task (leader_task) might be an already 2175 * unlinked task, which cannot be used to access the task-list 2176 * via next_thread(). 2177 */ 2178 if (pid_alive(task)) do { 2179 int tid = task->pid; 2180 2181 if (--index >= 0) 2182 continue; 2183 if (tids != NULL) 2184 tids[nr_tids] = tid; 2185 nr_tids++; 2186 if (nr_tids >= PROC_MAXPIDS) 2187 break; 2188 } while ((task = next_thread(task)) != leader_task); 2189 read_unlock(&tasklist_lock); 2190 return nr_tids; 2191 } 2192 2193 /* for the /proc/ directory itself, after non-process stuff has been done */ 2194 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2195 { 2196 unsigned int tgid_array[PROC_MAXPIDS]; 2197 char buf[PROC_NUMBUF]; 2198 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2199 unsigned int nr_tgids, i; 2200 int next_tgid; 2201 2202 if (!nr) { 2203 ino_t ino = fake_ino(0,PROC_TGID_INO); 2204 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0) 2205 return 0; 2206 filp->f_pos++; 2207 nr++; 2208 } 2209 2210 /* f_version caches the tgid value that the last readdir call couldn't 2211 * return. lseek aka telldir automagically resets f_version to 0. 2212 */ 2213 next_tgid = filp->f_version; 2214 filp->f_version = 0; 2215 for (;;) { 2216 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array); 2217 if (!nr_tgids) { 2218 /* no more entries ! */ 2219 break; 2220 } 2221 next_tgid = 0; 2222 2223 /* do not use the last found pid, reserve it for next_tgid */ 2224 if (nr_tgids == PROC_MAXPIDS) { 2225 nr_tgids--; 2226 next_tgid = tgid_array[nr_tgids]; 2227 } 2228 2229 for (i=0;i<nr_tgids;i++) { 2230 int tgid = tgid_array[i]; 2231 ino_t ino = fake_ino(tgid,PROC_TGID_INO); 2232 unsigned long j = PROC_NUMBUF; 2233 2234 do 2235 buf[--j] = '0' + (tgid % 10); 2236 while ((tgid /= 10) != 0); 2237 2238 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) { 2239 /* returning this tgid failed, save it as the first 2240 * pid for the next readir call */ 2241 filp->f_version = tgid_array[i]; 2242 goto out; 2243 } 2244 filp->f_pos++; 2245 nr++; 2246 } 2247 } 2248 out: 2249 return 0; 2250 } 2251 2252 /* for the /proc/TGID/task/ directories */ 2253 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 2254 { 2255 unsigned int tid_array[PROC_MAXPIDS]; 2256 char buf[PROC_NUMBUF]; 2257 unsigned int nr_tids, i; 2258 struct dentry *dentry = filp->f_dentry; 2259 struct inode *inode = dentry->d_inode; 2260 int retval = -ENOENT; 2261 ino_t ino; 2262 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ 2263 2264 if (!pid_alive(proc_task(inode))) 2265 goto out; 2266 retval = 0; 2267 2268 switch (pos) { 2269 case 0: 2270 ino = inode->i_ino; 2271 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) 2272 goto out; 2273 pos++; 2274 /* fall through */ 2275 case 1: 2276 ino = parent_ino(dentry); 2277 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) 2278 goto out; 2279 pos++; 2280 /* fall through */ 2281 } 2282 2283 nr_tids = get_tid_list(pos, tid_array, inode); 2284 inode->i_nlink = pos + nr_tids; 2285 2286 for (i = 0; i < nr_tids; i++) { 2287 unsigned long j = PROC_NUMBUF; 2288 int tid = tid_array[i]; 2289 2290 ino = fake_ino(tid,PROC_TID_INO); 2291 2292 do 2293 buf[--j] = '0' + (tid % 10); 2294 while ((tid /= 10) != 0); 2295 2296 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0) 2297 break; 2298 pos++; 2299 } 2300 out: 2301 filp->f_pos = pos; 2302 return retval; 2303 } 2304