1 /* 2 * sysctl.c: General linux system control interface 3 * 4 * Begun 24 March 1995, Stephen Tweedie 5 * Added /proc support, Dec 1995 6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas. 7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver. 8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver. 9 * Dynamic registration fixes, Stephen Tweedie. 10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn. 11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris 12 * Horn. 13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer. 14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer. 15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill 16 * Wendling. 17 * The list_for_each() macro wasn't appropriate for the sysctl loop. 18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/mm.h> 24 #include <linux/swap.h> 25 #include <linux/slab.h> 26 #include <linux/sysctl.h> 27 #include <linux/proc_fs.h> 28 #include <linux/capability.h> 29 #include <linux/ctype.h> 30 #include <linux/utsname.h> 31 #include <linux/capability.h> 32 #include <linux/smp_lock.h> 33 #include <linux/init.h> 34 #include <linux/kernel.h> 35 #include <linux/kobject.h> 36 #include <linux/net.h> 37 #include <linux/sysrq.h> 38 #include <linux/highuid.h> 39 #include <linux/writeback.h> 40 #include <linux/hugetlb.h> 41 #include <linux/security.h> 42 #include <linux/initrd.h> 43 #include <linux/times.h> 44 #include <linux/limits.h> 45 #include <linux/dcache.h> 46 #include <linux/syscalls.h> 47 48 #include <asm/uaccess.h> 49 #include <asm/processor.h> 50 51 #ifdef CONFIG_ROOT_NFS 52 #include <linux/nfs_fs.h> 53 #endif 54 55 #if defined(CONFIG_SYSCTL) 56 57 /* External variables not in a header file. */ 58 extern int C_A_D; 59 extern int sysctl_overcommit_memory; 60 extern int sysctl_overcommit_ratio; 61 extern int max_threads; 62 extern int sysrq_enabled; 63 extern int core_uses_pid; 64 extern int suid_dumpable; 65 extern char core_pattern[]; 66 extern int cad_pid; 67 extern int pid_max; 68 extern int min_free_kbytes; 69 extern int printk_ratelimit_jiffies; 70 extern int printk_ratelimit_burst; 71 extern int pid_max_min, pid_max_max; 72 extern int sysctl_drop_caches; 73 extern int percpu_pagelist_fraction; 74 75 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 76 int unknown_nmi_panic; 77 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *, 78 void __user *, size_t *, loff_t *); 79 #endif 80 81 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ 82 static int maxolduid = 65535; 83 static int minolduid; 84 static int min_percpu_pagelist_fract = 8; 85 86 static int ngroups_max = NGROUPS_MAX; 87 88 #ifdef CONFIG_KMOD 89 extern char modprobe_path[]; 90 #endif 91 #ifdef CONFIG_CHR_DEV_SG 92 extern int sg_big_buff; 93 #endif 94 #ifdef CONFIG_SYSVIPC 95 extern size_t shm_ctlmax; 96 extern size_t shm_ctlall; 97 extern int shm_ctlmni; 98 extern int msg_ctlmax; 99 extern int msg_ctlmnb; 100 extern int msg_ctlmni; 101 extern int sem_ctls[]; 102 #endif 103 104 #ifdef __sparc__ 105 extern char reboot_command []; 106 extern int stop_a_enabled; 107 extern int scons_pwroff; 108 #endif 109 110 #ifdef __hppa__ 111 extern int pwrsw_enabled; 112 extern int unaligned_enabled; 113 #endif 114 115 #ifdef CONFIG_S390 116 #ifdef CONFIG_MATHEMU 117 extern int sysctl_ieee_emulation_warnings; 118 #endif 119 extern int sysctl_userprocess_debug; 120 extern int spin_retry; 121 #endif 122 123 extern int sysctl_hz_timer; 124 125 #ifdef CONFIG_BSD_PROCESS_ACCT 126 extern int acct_parm[]; 127 #endif 128 129 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t, 130 ctl_table *, void **); 131 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 132 void __user *buffer, size_t *lenp, loff_t *ppos); 133 134 static ctl_table root_table[]; 135 static struct ctl_table_header root_table_header = 136 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; 137 138 static ctl_table kern_table[]; 139 static ctl_table vm_table[]; 140 static ctl_table proc_table[]; 141 static ctl_table fs_table[]; 142 static ctl_table debug_table[]; 143 static ctl_table dev_table[]; 144 extern ctl_table random_table[]; 145 #ifdef CONFIG_UNIX98_PTYS 146 extern ctl_table pty_table[]; 147 #endif 148 #ifdef CONFIG_INOTIFY 149 extern ctl_table inotify_table[]; 150 #endif 151 152 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 153 int sysctl_legacy_va_layout; 154 #endif 155 156 /* /proc declarations: */ 157 158 #ifdef CONFIG_PROC_FS 159 160 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *); 161 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *); 162 static int proc_opensys(struct inode *, struct file *); 163 164 struct file_operations proc_sys_file_operations = { 165 .open = proc_opensys, 166 .read = proc_readsys, 167 .write = proc_writesys, 168 }; 169 170 extern struct proc_dir_entry *proc_sys_root; 171 172 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *); 173 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *); 174 #endif 175 176 /* The default sysctl tables: */ 177 178 static ctl_table root_table[] = { 179 { 180 .ctl_name = CTL_KERN, 181 .procname = "kernel", 182 .mode = 0555, 183 .child = kern_table, 184 }, 185 { 186 .ctl_name = CTL_VM, 187 .procname = "vm", 188 .mode = 0555, 189 .child = vm_table, 190 }, 191 #ifdef CONFIG_NET 192 { 193 .ctl_name = CTL_NET, 194 .procname = "net", 195 .mode = 0555, 196 .child = net_table, 197 }, 198 #endif 199 { 200 .ctl_name = CTL_PROC, 201 .procname = "proc", 202 .mode = 0555, 203 .child = proc_table, 204 }, 205 { 206 .ctl_name = CTL_FS, 207 .procname = "fs", 208 .mode = 0555, 209 .child = fs_table, 210 }, 211 { 212 .ctl_name = CTL_DEBUG, 213 .procname = "debug", 214 .mode = 0555, 215 .child = debug_table, 216 }, 217 { 218 .ctl_name = CTL_DEV, 219 .procname = "dev", 220 .mode = 0555, 221 .child = dev_table, 222 }, 223 224 { .ctl_name = 0 } 225 }; 226 227 static ctl_table kern_table[] = { 228 { 229 .ctl_name = KERN_OSTYPE, 230 .procname = "ostype", 231 .data = system_utsname.sysname, 232 .maxlen = sizeof(system_utsname.sysname), 233 .mode = 0444, 234 .proc_handler = &proc_doutsstring, 235 .strategy = &sysctl_string, 236 }, 237 { 238 .ctl_name = KERN_OSRELEASE, 239 .procname = "osrelease", 240 .data = system_utsname.release, 241 .maxlen = sizeof(system_utsname.release), 242 .mode = 0444, 243 .proc_handler = &proc_doutsstring, 244 .strategy = &sysctl_string, 245 }, 246 { 247 .ctl_name = KERN_VERSION, 248 .procname = "version", 249 .data = system_utsname.version, 250 .maxlen = sizeof(system_utsname.version), 251 .mode = 0444, 252 .proc_handler = &proc_doutsstring, 253 .strategy = &sysctl_string, 254 }, 255 { 256 .ctl_name = KERN_NODENAME, 257 .procname = "hostname", 258 .data = system_utsname.nodename, 259 .maxlen = sizeof(system_utsname.nodename), 260 .mode = 0644, 261 .proc_handler = &proc_doutsstring, 262 .strategy = &sysctl_string, 263 }, 264 { 265 .ctl_name = KERN_DOMAINNAME, 266 .procname = "domainname", 267 .data = system_utsname.domainname, 268 .maxlen = sizeof(system_utsname.domainname), 269 .mode = 0644, 270 .proc_handler = &proc_doutsstring, 271 .strategy = &sysctl_string, 272 }, 273 { 274 .ctl_name = KERN_PANIC, 275 .procname = "panic", 276 .data = &panic_timeout, 277 .maxlen = sizeof(int), 278 .mode = 0644, 279 .proc_handler = &proc_dointvec, 280 }, 281 { 282 .ctl_name = KERN_CORE_USES_PID, 283 .procname = "core_uses_pid", 284 .data = &core_uses_pid, 285 .maxlen = sizeof(int), 286 .mode = 0644, 287 .proc_handler = &proc_dointvec, 288 }, 289 { 290 .ctl_name = KERN_CORE_PATTERN, 291 .procname = "core_pattern", 292 .data = core_pattern, 293 .maxlen = 64, 294 .mode = 0644, 295 .proc_handler = &proc_dostring, 296 .strategy = &sysctl_string, 297 }, 298 { 299 .ctl_name = KERN_TAINTED, 300 .procname = "tainted", 301 .data = &tainted, 302 .maxlen = sizeof(int), 303 .mode = 0444, 304 .proc_handler = &proc_dointvec, 305 }, 306 { 307 .ctl_name = KERN_CAP_BSET, 308 .procname = "cap-bound", 309 .data = &cap_bset, 310 .maxlen = sizeof(kernel_cap_t), 311 .mode = 0600, 312 .proc_handler = &proc_dointvec_bset, 313 }, 314 #ifdef CONFIG_BLK_DEV_INITRD 315 { 316 .ctl_name = KERN_REALROOTDEV, 317 .procname = "real-root-dev", 318 .data = &real_root_dev, 319 .maxlen = sizeof(int), 320 .mode = 0644, 321 .proc_handler = &proc_dointvec, 322 }, 323 #endif 324 #ifdef __sparc__ 325 { 326 .ctl_name = KERN_SPARC_REBOOT, 327 .procname = "reboot-cmd", 328 .data = reboot_command, 329 .maxlen = 256, 330 .mode = 0644, 331 .proc_handler = &proc_dostring, 332 .strategy = &sysctl_string, 333 }, 334 { 335 .ctl_name = KERN_SPARC_STOP_A, 336 .procname = "stop-a", 337 .data = &stop_a_enabled, 338 .maxlen = sizeof (int), 339 .mode = 0644, 340 .proc_handler = &proc_dointvec, 341 }, 342 { 343 .ctl_name = KERN_SPARC_SCONS_PWROFF, 344 .procname = "scons-poweroff", 345 .data = &scons_pwroff, 346 .maxlen = sizeof (int), 347 .mode = 0644, 348 .proc_handler = &proc_dointvec, 349 }, 350 #endif 351 #ifdef __hppa__ 352 { 353 .ctl_name = KERN_HPPA_PWRSW, 354 .procname = "soft-power", 355 .data = &pwrsw_enabled, 356 .maxlen = sizeof (int), 357 .mode = 0644, 358 .proc_handler = &proc_dointvec, 359 }, 360 { 361 .ctl_name = KERN_HPPA_UNALIGNED, 362 .procname = "unaligned-trap", 363 .data = &unaligned_enabled, 364 .maxlen = sizeof (int), 365 .mode = 0644, 366 .proc_handler = &proc_dointvec, 367 }, 368 #endif 369 { 370 .ctl_name = KERN_CTLALTDEL, 371 .procname = "ctrl-alt-del", 372 .data = &C_A_D, 373 .maxlen = sizeof(int), 374 .mode = 0644, 375 .proc_handler = &proc_dointvec, 376 }, 377 { 378 .ctl_name = KERN_PRINTK, 379 .procname = "printk", 380 .data = &console_loglevel, 381 .maxlen = 4*sizeof(int), 382 .mode = 0644, 383 .proc_handler = &proc_dointvec, 384 }, 385 #ifdef CONFIG_KMOD 386 { 387 .ctl_name = KERN_MODPROBE, 388 .procname = "modprobe", 389 .data = &modprobe_path, 390 .maxlen = KMOD_PATH_LEN, 391 .mode = 0644, 392 .proc_handler = &proc_dostring, 393 .strategy = &sysctl_string, 394 }, 395 #endif 396 #ifdef CONFIG_HOTPLUG 397 { 398 .ctl_name = KERN_HOTPLUG, 399 .procname = "hotplug", 400 .data = &uevent_helper, 401 .maxlen = UEVENT_HELPER_PATH_LEN, 402 .mode = 0644, 403 .proc_handler = &proc_dostring, 404 .strategy = &sysctl_string, 405 }, 406 #endif 407 #ifdef CONFIG_CHR_DEV_SG 408 { 409 .ctl_name = KERN_SG_BIG_BUFF, 410 .procname = "sg-big-buff", 411 .data = &sg_big_buff, 412 .maxlen = sizeof (int), 413 .mode = 0444, 414 .proc_handler = &proc_dointvec, 415 }, 416 #endif 417 #ifdef CONFIG_BSD_PROCESS_ACCT 418 { 419 .ctl_name = KERN_ACCT, 420 .procname = "acct", 421 .data = &acct_parm, 422 .maxlen = 3*sizeof(int), 423 .mode = 0644, 424 .proc_handler = &proc_dointvec, 425 }, 426 #endif 427 #ifdef CONFIG_SYSVIPC 428 { 429 .ctl_name = KERN_SHMMAX, 430 .procname = "shmmax", 431 .data = &shm_ctlmax, 432 .maxlen = sizeof (size_t), 433 .mode = 0644, 434 .proc_handler = &proc_doulongvec_minmax, 435 }, 436 { 437 .ctl_name = KERN_SHMALL, 438 .procname = "shmall", 439 .data = &shm_ctlall, 440 .maxlen = sizeof (size_t), 441 .mode = 0644, 442 .proc_handler = &proc_doulongvec_minmax, 443 }, 444 { 445 .ctl_name = KERN_SHMMNI, 446 .procname = "shmmni", 447 .data = &shm_ctlmni, 448 .maxlen = sizeof (int), 449 .mode = 0644, 450 .proc_handler = &proc_dointvec, 451 }, 452 { 453 .ctl_name = KERN_MSGMAX, 454 .procname = "msgmax", 455 .data = &msg_ctlmax, 456 .maxlen = sizeof (int), 457 .mode = 0644, 458 .proc_handler = &proc_dointvec, 459 }, 460 { 461 .ctl_name = KERN_MSGMNI, 462 .procname = "msgmni", 463 .data = &msg_ctlmni, 464 .maxlen = sizeof (int), 465 .mode = 0644, 466 .proc_handler = &proc_dointvec, 467 }, 468 { 469 .ctl_name = KERN_MSGMNB, 470 .procname = "msgmnb", 471 .data = &msg_ctlmnb, 472 .maxlen = sizeof (int), 473 .mode = 0644, 474 .proc_handler = &proc_dointvec, 475 }, 476 { 477 .ctl_name = KERN_SEM, 478 .procname = "sem", 479 .data = &sem_ctls, 480 .maxlen = 4*sizeof (int), 481 .mode = 0644, 482 .proc_handler = &proc_dointvec, 483 }, 484 #endif 485 #ifdef CONFIG_MAGIC_SYSRQ 486 { 487 .ctl_name = KERN_SYSRQ, 488 .procname = "sysrq", 489 .data = &sysrq_enabled, 490 .maxlen = sizeof (int), 491 .mode = 0644, 492 .proc_handler = &proc_dointvec, 493 }, 494 #endif 495 { 496 .ctl_name = KERN_CADPID, 497 .procname = "cad_pid", 498 .data = &cad_pid, 499 .maxlen = sizeof (int), 500 .mode = 0600, 501 .proc_handler = &proc_dointvec, 502 }, 503 { 504 .ctl_name = KERN_MAX_THREADS, 505 .procname = "threads-max", 506 .data = &max_threads, 507 .maxlen = sizeof(int), 508 .mode = 0644, 509 .proc_handler = &proc_dointvec, 510 }, 511 { 512 .ctl_name = KERN_RANDOM, 513 .procname = "random", 514 .mode = 0555, 515 .child = random_table, 516 }, 517 #ifdef CONFIG_UNIX98_PTYS 518 { 519 .ctl_name = KERN_PTY, 520 .procname = "pty", 521 .mode = 0555, 522 .child = pty_table, 523 }, 524 #endif 525 { 526 .ctl_name = KERN_OVERFLOWUID, 527 .procname = "overflowuid", 528 .data = &overflowuid, 529 .maxlen = sizeof(int), 530 .mode = 0644, 531 .proc_handler = &proc_dointvec_minmax, 532 .strategy = &sysctl_intvec, 533 .extra1 = &minolduid, 534 .extra2 = &maxolduid, 535 }, 536 { 537 .ctl_name = KERN_OVERFLOWGID, 538 .procname = "overflowgid", 539 .data = &overflowgid, 540 .maxlen = sizeof(int), 541 .mode = 0644, 542 .proc_handler = &proc_dointvec_minmax, 543 .strategy = &sysctl_intvec, 544 .extra1 = &minolduid, 545 .extra2 = &maxolduid, 546 }, 547 #ifdef CONFIG_S390 548 #ifdef CONFIG_MATHEMU 549 { 550 .ctl_name = KERN_IEEE_EMULATION_WARNINGS, 551 .procname = "ieee_emulation_warnings", 552 .data = &sysctl_ieee_emulation_warnings, 553 .maxlen = sizeof(int), 554 .mode = 0644, 555 .proc_handler = &proc_dointvec, 556 }, 557 #endif 558 #ifdef CONFIG_NO_IDLE_HZ 559 { 560 .ctl_name = KERN_HZ_TIMER, 561 .procname = "hz_timer", 562 .data = &sysctl_hz_timer, 563 .maxlen = sizeof(int), 564 .mode = 0644, 565 .proc_handler = &proc_dointvec, 566 }, 567 #endif 568 { 569 .ctl_name = KERN_S390_USER_DEBUG_LOGGING, 570 .procname = "userprocess_debug", 571 .data = &sysctl_userprocess_debug, 572 .maxlen = sizeof(int), 573 .mode = 0644, 574 .proc_handler = &proc_dointvec, 575 }, 576 #endif 577 { 578 .ctl_name = KERN_PIDMAX, 579 .procname = "pid_max", 580 .data = &pid_max, 581 .maxlen = sizeof (int), 582 .mode = 0644, 583 .proc_handler = &proc_dointvec_minmax, 584 .strategy = sysctl_intvec, 585 .extra1 = &pid_max_min, 586 .extra2 = &pid_max_max, 587 }, 588 { 589 .ctl_name = KERN_PANIC_ON_OOPS, 590 .procname = "panic_on_oops", 591 .data = &panic_on_oops, 592 .maxlen = sizeof(int), 593 .mode = 0644, 594 .proc_handler = &proc_dointvec, 595 }, 596 { 597 .ctl_name = KERN_PRINTK_RATELIMIT, 598 .procname = "printk_ratelimit", 599 .data = &printk_ratelimit_jiffies, 600 .maxlen = sizeof(int), 601 .mode = 0644, 602 .proc_handler = &proc_dointvec_jiffies, 603 .strategy = &sysctl_jiffies, 604 }, 605 { 606 .ctl_name = KERN_PRINTK_RATELIMIT_BURST, 607 .procname = "printk_ratelimit_burst", 608 .data = &printk_ratelimit_burst, 609 .maxlen = sizeof(int), 610 .mode = 0644, 611 .proc_handler = &proc_dointvec, 612 }, 613 { 614 .ctl_name = KERN_NGROUPS_MAX, 615 .procname = "ngroups_max", 616 .data = &ngroups_max, 617 .maxlen = sizeof (int), 618 .mode = 0444, 619 .proc_handler = &proc_dointvec, 620 }, 621 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 622 { 623 .ctl_name = KERN_UNKNOWN_NMI_PANIC, 624 .procname = "unknown_nmi_panic", 625 .data = &unknown_nmi_panic, 626 .maxlen = sizeof (int), 627 .mode = 0644, 628 .proc_handler = &proc_unknown_nmi_panic, 629 }, 630 #endif 631 #if defined(CONFIG_X86) 632 { 633 .ctl_name = KERN_BOOTLOADER_TYPE, 634 .procname = "bootloader_type", 635 .data = &bootloader_type, 636 .maxlen = sizeof (int), 637 .mode = 0444, 638 .proc_handler = &proc_dointvec, 639 }, 640 #endif 641 { 642 .ctl_name = KERN_RANDOMIZE, 643 .procname = "randomize_va_space", 644 .data = &randomize_va_space, 645 .maxlen = sizeof(int), 646 .mode = 0644, 647 .proc_handler = &proc_dointvec, 648 }, 649 #if defined(CONFIG_S390) && defined(CONFIG_SMP) 650 { 651 .ctl_name = KERN_SPIN_RETRY, 652 .procname = "spin_retry", 653 .data = &spin_retry, 654 .maxlen = sizeof (int), 655 .mode = 0644, 656 .proc_handler = &proc_dointvec, 657 }, 658 #endif 659 { .ctl_name = 0 } 660 }; 661 662 /* Constants for minimum and maximum testing in vm_table. 663 We use these as one-element integer vectors. */ 664 static int zero; 665 static int one_hundred = 100; 666 667 668 static ctl_table vm_table[] = { 669 { 670 .ctl_name = VM_OVERCOMMIT_MEMORY, 671 .procname = "overcommit_memory", 672 .data = &sysctl_overcommit_memory, 673 .maxlen = sizeof(sysctl_overcommit_memory), 674 .mode = 0644, 675 .proc_handler = &proc_dointvec, 676 }, 677 { 678 .ctl_name = VM_OVERCOMMIT_RATIO, 679 .procname = "overcommit_ratio", 680 .data = &sysctl_overcommit_ratio, 681 .maxlen = sizeof(sysctl_overcommit_ratio), 682 .mode = 0644, 683 .proc_handler = &proc_dointvec, 684 }, 685 { 686 .ctl_name = VM_PAGE_CLUSTER, 687 .procname = "page-cluster", 688 .data = &page_cluster, 689 .maxlen = sizeof(int), 690 .mode = 0644, 691 .proc_handler = &proc_dointvec, 692 }, 693 { 694 .ctl_name = VM_DIRTY_BACKGROUND, 695 .procname = "dirty_background_ratio", 696 .data = &dirty_background_ratio, 697 .maxlen = sizeof(dirty_background_ratio), 698 .mode = 0644, 699 .proc_handler = &proc_dointvec_minmax, 700 .strategy = &sysctl_intvec, 701 .extra1 = &zero, 702 .extra2 = &one_hundred, 703 }, 704 { 705 .ctl_name = VM_DIRTY_RATIO, 706 .procname = "dirty_ratio", 707 .data = &vm_dirty_ratio, 708 .maxlen = sizeof(vm_dirty_ratio), 709 .mode = 0644, 710 .proc_handler = &proc_dointvec_minmax, 711 .strategy = &sysctl_intvec, 712 .extra1 = &zero, 713 .extra2 = &one_hundred, 714 }, 715 { 716 .ctl_name = VM_DIRTY_WB_CS, 717 .procname = "dirty_writeback_centisecs", 718 .data = &dirty_writeback_centisecs, 719 .maxlen = sizeof(dirty_writeback_centisecs), 720 .mode = 0644, 721 .proc_handler = &dirty_writeback_centisecs_handler, 722 }, 723 { 724 .ctl_name = VM_DIRTY_EXPIRE_CS, 725 .procname = "dirty_expire_centisecs", 726 .data = &dirty_expire_centisecs, 727 .maxlen = sizeof(dirty_expire_centisecs), 728 .mode = 0644, 729 .proc_handler = &proc_dointvec, 730 }, 731 { 732 .ctl_name = VM_NR_PDFLUSH_THREADS, 733 .procname = "nr_pdflush_threads", 734 .data = &nr_pdflush_threads, 735 .maxlen = sizeof nr_pdflush_threads, 736 .mode = 0444 /* read-only*/, 737 .proc_handler = &proc_dointvec, 738 }, 739 { 740 .ctl_name = VM_SWAPPINESS, 741 .procname = "swappiness", 742 .data = &vm_swappiness, 743 .maxlen = sizeof(vm_swappiness), 744 .mode = 0644, 745 .proc_handler = &proc_dointvec_minmax, 746 .strategy = &sysctl_intvec, 747 .extra1 = &zero, 748 .extra2 = &one_hundred, 749 }, 750 #ifdef CONFIG_HUGETLB_PAGE 751 { 752 .ctl_name = VM_HUGETLB_PAGES, 753 .procname = "nr_hugepages", 754 .data = &max_huge_pages, 755 .maxlen = sizeof(unsigned long), 756 .mode = 0644, 757 .proc_handler = &hugetlb_sysctl_handler, 758 .extra1 = (void *)&hugetlb_zero, 759 .extra2 = (void *)&hugetlb_infinity, 760 }, 761 { 762 .ctl_name = VM_HUGETLB_GROUP, 763 .procname = "hugetlb_shm_group", 764 .data = &sysctl_hugetlb_shm_group, 765 .maxlen = sizeof(gid_t), 766 .mode = 0644, 767 .proc_handler = &proc_dointvec, 768 }, 769 #endif 770 { 771 .ctl_name = VM_LOWMEM_RESERVE_RATIO, 772 .procname = "lowmem_reserve_ratio", 773 .data = &sysctl_lowmem_reserve_ratio, 774 .maxlen = sizeof(sysctl_lowmem_reserve_ratio), 775 .mode = 0644, 776 .proc_handler = &lowmem_reserve_ratio_sysctl_handler, 777 .strategy = &sysctl_intvec, 778 }, 779 { 780 .ctl_name = VM_DROP_PAGECACHE, 781 .procname = "drop_caches", 782 .data = &sysctl_drop_caches, 783 .maxlen = sizeof(int), 784 .mode = 0644, 785 .proc_handler = drop_caches_sysctl_handler, 786 .strategy = &sysctl_intvec, 787 }, 788 { 789 .ctl_name = VM_MIN_FREE_KBYTES, 790 .procname = "min_free_kbytes", 791 .data = &min_free_kbytes, 792 .maxlen = sizeof(min_free_kbytes), 793 .mode = 0644, 794 .proc_handler = &min_free_kbytes_sysctl_handler, 795 .strategy = &sysctl_intvec, 796 .extra1 = &zero, 797 }, 798 { 799 .ctl_name = VM_PERCPU_PAGELIST_FRACTION, 800 .procname = "percpu_pagelist_fraction", 801 .data = &percpu_pagelist_fraction, 802 .maxlen = sizeof(percpu_pagelist_fraction), 803 .mode = 0644, 804 .proc_handler = &percpu_pagelist_fraction_sysctl_handler, 805 .strategy = &sysctl_intvec, 806 .extra1 = &min_percpu_pagelist_fract, 807 }, 808 #ifdef CONFIG_MMU 809 { 810 .ctl_name = VM_MAX_MAP_COUNT, 811 .procname = "max_map_count", 812 .data = &sysctl_max_map_count, 813 .maxlen = sizeof(sysctl_max_map_count), 814 .mode = 0644, 815 .proc_handler = &proc_dointvec 816 }, 817 #endif 818 { 819 .ctl_name = VM_LAPTOP_MODE, 820 .procname = "laptop_mode", 821 .data = &laptop_mode, 822 .maxlen = sizeof(laptop_mode), 823 .mode = 0644, 824 .proc_handler = &proc_dointvec, 825 .strategy = &sysctl_intvec, 826 .extra1 = &zero, 827 }, 828 { 829 .ctl_name = VM_BLOCK_DUMP, 830 .procname = "block_dump", 831 .data = &block_dump, 832 .maxlen = sizeof(block_dump), 833 .mode = 0644, 834 .proc_handler = &proc_dointvec, 835 .strategy = &sysctl_intvec, 836 .extra1 = &zero, 837 }, 838 { 839 .ctl_name = VM_VFS_CACHE_PRESSURE, 840 .procname = "vfs_cache_pressure", 841 .data = &sysctl_vfs_cache_pressure, 842 .maxlen = sizeof(sysctl_vfs_cache_pressure), 843 .mode = 0644, 844 .proc_handler = &proc_dointvec, 845 .strategy = &sysctl_intvec, 846 .extra1 = &zero, 847 }, 848 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 849 { 850 .ctl_name = VM_LEGACY_VA_LAYOUT, 851 .procname = "legacy_va_layout", 852 .data = &sysctl_legacy_va_layout, 853 .maxlen = sizeof(sysctl_legacy_va_layout), 854 .mode = 0644, 855 .proc_handler = &proc_dointvec, 856 .strategy = &sysctl_intvec, 857 .extra1 = &zero, 858 }, 859 #endif 860 #ifdef CONFIG_SWAP 861 { 862 .ctl_name = VM_SWAP_TOKEN_TIMEOUT, 863 .procname = "swap_token_timeout", 864 .data = &swap_token_default_timeout, 865 .maxlen = sizeof(swap_token_default_timeout), 866 .mode = 0644, 867 .proc_handler = &proc_dointvec_jiffies, 868 .strategy = &sysctl_jiffies, 869 }, 870 #endif 871 #ifdef CONFIG_NUMA 872 { 873 .ctl_name = VM_ZONE_RECLAIM_MODE, 874 .procname = "zone_reclaim_mode", 875 .data = &zone_reclaim_mode, 876 .maxlen = sizeof(zone_reclaim_mode), 877 .mode = 0644, 878 .proc_handler = &proc_dointvec, 879 .strategy = &sysctl_intvec, 880 .extra1 = &zero, 881 }, 882 { 883 .ctl_name = VM_ZONE_RECLAIM_INTERVAL, 884 .procname = "zone_reclaim_interval", 885 .data = &zone_reclaim_interval, 886 .maxlen = sizeof(zone_reclaim_interval), 887 .mode = 0644, 888 .proc_handler = &proc_dointvec_jiffies, 889 .strategy = &sysctl_jiffies, 890 }, 891 #endif 892 { .ctl_name = 0 } 893 }; 894 895 static ctl_table proc_table[] = { 896 { .ctl_name = 0 } 897 }; 898 899 static ctl_table fs_table[] = { 900 { 901 .ctl_name = FS_NRINODE, 902 .procname = "inode-nr", 903 .data = &inodes_stat, 904 .maxlen = 2*sizeof(int), 905 .mode = 0444, 906 .proc_handler = &proc_dointvec, 907 }, 908 { 909 .ctl_name = FS_STATINODE, 910 .procname = "inode-state", 911 .data = &inodes_stat, 912 .maxlen = 7*sizeof(int), 913 .mode = 0444, 914 .proc_handler = &proc_dointvec, 915 }, 916 { 917 .ctl_name = FS_NRFILE, 918 .procname = "file-nr", 919 .data = &files_stat, 920 .maxlen = 3*sizeof(int), 921 .mode = 0444, 922 .proc_handler = &proc_dointvec, 923 }, 924 { 925 .ctl_name = FS_MAXFILE, 926 .procname = "file-max", 927 .data = &files_stat.max_files, 928 .maxlen = sizeof(int), 929 .mode = 0644, 930 .proc_handler = &proc_dointvec, 931 }, 932 { 933 .ctl_name = FS_DENTRY, 934 .procname = "dentry-state", 935 .data = &dentry_stat, 936 .maxlen = 6*sizeof(int), 937 .mode = 0444, 938 .proc_handler = &proc_dointvec, 939 }, 940 { 941 .ctl_name = FS_OVERFLOWUID, 942 .procname = "overflowuid", 943 .data = &fs_overflowuid, 944 .maxlen = sizeof(int), 945 .mode = 0644, 946 .proc_handler = &proc_dointvec_minmax, 947 .strategy = &sysctl_intvec, 948 .extra1 = &minolduid, 949 .extra2 = &maxolduid, 950 }, 951 { 952 .ctl_name = FS_OVERFLOWGID, 953 .procname = "overflowgid", 954 .data = &fs_overflowgid, 955 .maxlen = sizeof(int), 956 .mode = 0644, 957 .proc_handler = &proc_dointvec_minmax, 958 .strategy = &sysctl_intvec, 959 .extra1 = &minolduid, 960 .extra2 = &maxolduid, 961 }, 962 { 963 .ctl_name = FS_LEASES, 964 .procname = "leases-enable", 965 .data = &leases_enable, 966 .maxlen = sizeof(int), 967 .mode = 0644, 968 .proc_handler = &proc_dointvec, 969 }, 970 #ifdef CONFIG_DNOTIFY 971 { 972 .ctl_name = FS_DIR_NOTIFY, 973 .procname = "dir-notify-enable", 974 .data = &dir_notify_enable, 975 .maxlen = sizeof(int), 976 .mode = 0644, 977 .proc_handler = &proc_dointvec, 978 }, 979 #endif 980 #ifdef CONFIG_MMU 981 { 982 .ctl_name = FS_LEASE_TIME, 983 .procname = "lease-break-time", 984 .data = &lease_break_time, 985 .maxlen = sizeof(int), 986 .mode = 0644, 987 .proc_handler = &proc_dointvec, 988 }, 989 { 990 .ctl_name = FS_AIO_NR, 991 .procname = "aio-nr", 992 .data = &aio_nr, 993 .maxlen = sizeof(aio_nr), 994 .mode = 0444, 995 .proc_handler = &proc_doulongvec_minmax, 996 }, 997 { 998 .ctl_name = FS_AIO_MAX_NR, 999 .procname = "aio-max-nr", 1000 .data = &aio_max_nr, 1001 .maxlen = sizeof(aio_max_nr), 1002 .mode = 0644, 1003 .proc_handler = &proc_doulongvec_minmax, 1004 }, 1005 #ifdef CONFIG_INOTIFY 1006 { 1007 .ctl_name = FS_INOTIFY, 1008 .procname = "inotify", 1009 .mode = 0555, 1010 .child = inotify_table, 1011 }, 1012 #endif 1013 #endif 1014 { 1015 .ctl_name = KERN_SETUID_DUMPABLE, 1016 .procname = "suid_dumpable", 1017 .data = &suid_dumpable, 1018 .maxlen = sizeof(int), 1019 .mode = 0644, 1020 .proc_handler = &proc_dointvec, 1021 }, 1022 { .ctl_name = 0 } 1023 }; 1024 1025 static ctl_table debug_table[] = { 1026 { .ctl_name = 0 } 1027 }; 1028 1029 static ctl_table dev_table[] = { 1030 { .ctl_name = 0 } 1031 }; 1032 1033 extern void init_irq_proc (void); 1034 1035 static DEFINE_SPINLOCK(sysctl_lock); 1036 1037 /* called under sysctl_lock */ 1038 static int use_table(struct ctl_table_header *p) 1039 { 1040 if (unlikely(p->unregistering)) 1041 return 0; 1042 p->used++; 1043 return 1; 1044 } 1045 1046 /* called under sysctl_lock */ 1047 static void unuse_table(struct ctl_table_header *p) 1048 { 1049 if (!--p->used) 1050 if (unlikely(p->unregistering)) 1051 complete(p->unregistering); 1052 } 1053 1054 /* called under sysctl_lock, will reacquire if has to wait */ 1055 static void start_unregistering(struct ctl_table_header *p) 1056 { 1057 /* 1058 * if p->used is 0, nobody will ever touch that entry again; 1059 * we'll eliminate all paths to it before dropping sysctl_lock 1060 */ 1061 if (unlikely(p->used)) { 1062 struct completion wait; 1063 init_completion(&wait); 1064 p->unregistering = &wait; 1065 spin_unlock(&sysctl_lock); 1066 wait_for_completion(&wait); 1067 spin_lock(&sysctl_lock); 1068 } 1069 /* 1070 * do not remove from the list until nobody holds it; walking the 1071 * list in do_sysctl() relies on that. 1072 */ 1073 list_del_init(&p->ctl_entry); 1074 } 1075 1076 void __init sysctl_init(void) 1077 { 1078 #ifdef CONFIG_PROC_FS 1079 register_proc_table(root_table, proc_sys_root, &root_table_header); 1080 init_irq_proc(); 1081 #endif 1082 } 1083 1084 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1085 void __user *newval, size_t newlen) 1086 { 1087 struct list_head *tmp; 1088 int error = -ENOTDIR; 1089 1090 if (nlen <= 0 || nlen >= CTL_MAXNAME) 1091 return -ENOTDIR; 1092 if (oldval) { 1093 int old_len; 1094 if (!oldlenp || get_user(old_len, oldlenp)) 1095 return -EFAULT; 1096 } 1097 spin_lock(&sysctl_lock); 1098 tmp = &root_table_header.ctl_entry; 1099 do { 1100 struct ctl_table_header *head = 1101 list_entry(tmp, struct ctl_table_header, ctl_entry); 1102 void *context = NULL; 1103 1104 if (!use_table(head)) 1105 continue; 1106 1107 spin_unlock(&sysctl_lock); 1108 1109 error = parse_table(name, nlen, oldval, oldlenp, 1110 newval, newlen, head->ctl_table, 1111 &context); 1112 kfree(context); 1113 1114 spin_lock(&sysctl_lock); 1115 unuse_table(head); 1116 if (error != -ENOTDIR) 1117 break; 1118 } while ((tmp = tmp->next) != &root_table_header.ctl_entry); 1119 spin_unlock(&sysctl_lock); 1120 return error; 1121 } 1122 1123 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 1124 { 1125 struct __sysctl_args tmp; 1126 int error; 1127 1128 if (copy_from_user(&tmp, args, sizeof(tmp))) 1129 return -EFAULT; 1130 1131 lock_kernel(); 1132 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp, 1133 tmp.newval, tmp.newlen); 1134 unlock_kernel(); 1135 return error; 1136 } 1137 1138 /* 1139 * ctl_perm does NOT grant the superuser all rights automatically, because 1140 * some sysctl variables are readonly even to root. 1141 */ 1142 1143 static int test_perm(int mode, int op) 1144 { 1145 if (!current->euid) 1146 mode >>= 6; 1147 else if (in_egroup_p(0)) 1148 mode >>= 3; 1149 if ((mode & op & 0007) == op) 1150 return 0; 1151 return -EACCES; 1152 } 1153 1154 static inline int ctl_perm(ctl_table *table, int op) 1155 { 1156 int error; 1157 error = security_sysctl(table, op); 1158 if (error) 1159 return error; 1160 return test_perm(table->mode, op); 1161 } 1162 1163 static int parse_table(int __user *name, int nlen, 1164 void __user *oldval, size_t __user *oldlenp, 1165 void __user *newval, size_t newlen, 1166 ctl_table *table, void **context) 1167 { 1168 int n; 1169 repeat: 1170 if (!nlen) 1171 return -ENOTDIR; 1172 if (get_user(n, name)) 1173 return -EFAULT; 1174 for ( ; table->ctl_name; table++) { 1175 if (n == table->ctl_name || table->ctl_name == CTL_ANY) { 1176 int error; 1177 if (table->child) { 1178 if (ctl_perm(table, 001)) 1179 return -EPERM; 1180 if (table->strategy) { 1181 error = table->strategy( 1182 table, name, nlen, 1183 oldval, oldlenp, 1184 newval, newlen, context); 1185 if (error) 1186 return error; 1187 } 1188 name++; 1189 nlen--; 1190 table = table->child; 1191 goto repeat; 1192 } 1193 error = do_sysctl_strategy(table, name, nlen, 1194 oldval, oldlenp, 1195 newval, newlen, context); 1196 return error; 1197 } 1198 } 1199 return -ENOTDIR; 1200 } 1201 1202 /* Perform the actual read/write of a sysctl table entry. */ 1203 int do_sysctl_strategy (ctl_table *table, 1204 int __user *name, int nlen, 1205 void __user *oldval, size_t __user *oldlenp, 1206 void __user *newval, size_t newlen, void **context) 1207 { 1208 int op = 0, rc; 1209 size_t len; 1210 1211 if (oldval) 1212 op |= 004; 1213 if (newval) 1214 op |= 002; 1215 if (ctl_perm(table, op)) 1216 return -EPERM; 1217 1218 if (table->strategy) { 1219 rc = table->strategy(table, name, nlen, oldval, oldlenp, 1220 newval, newlen, context); 1221 if (rc < 0) 1222 return rc; 1223 if (rc > 0) 1224 return 0; 1225 } 1226 1227 /* If there is no strategy routine, or if the strategy returns 1228 * zero, proceed with automatic r/w */ 1229 if (table->data && table->maxlen) { 1230 if (oldval && oldlenp) { 1231 if (get_user(len, oldlenp)) 1232 return -EFAULT; 1233 if (len) { 1234 if (len > table->maxlen) 1235 len = table->maxlen; 1236 if(copy_to_user(oldval, table->data, len)) 1237 return -EFAULT; 1238 if(put_user(len, oldlenp)) 1239 return -EFAULT; 1240 } 1241 } 1242 if (newval && newlen) { 1243 len = newlen; 1244 if (len > table->maxlen) 1245 len = table->maxlen; 1246 if(copy_from_user(table->data, newval, len)) 1247 return -EFAULT; 1248 } 1249 } 1250 return 0; 1251 } 1252 1253 /** 1254 * register_sysctl_table - register a sysctl hierarchy 1255 * @table: the top-level table structure 1256 * @insert_at_head: whether the entry should be inserted in front or at the end 1257 * 1258 * Register a sysctl table hierarchy. @table should be a filled in ctl_table 1259 * array. An entry with a ctl_name of 0 terminates the table. 1260 * 1261 * The members of the &ctl_table structure are used as follows: 1262 * 1263 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number 1264 * must be unique within that level of sysctl 1265 * 1266 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not 1267 * enter a sysctl file 1268 * 1269 * data - a pointer to data for use by proc_handler 1270 * 1271 * maxlen - the maximum size in bytes of the data 1272 * 1273 * mode - the file permissions for the /proc/sys file, and for sysctl(2) 1274 * 1275 * child - a pointer to the child sysctl table if this entry is a directory, or 1276 * %NULL. 1277 * 1278 * proc_handler - the text handler routine (described below) 1279 * 1280 * strategy - the strategy routine (described below) 1281 * 1282 * de - for internal use by the sysctl routines 1283 * 1284 * extra1, extra2 - extra pointers usable by the proc handler routines 1285 * 1286 * Leaf nodes in the sysctl tree will be represented by a single file 1287 * under /proc; non-leaf nodes will be represented by directories. 1288 * 1289 * sysctl(2) can automatically manage read and write requests through 1290 * the sysctl table. The data and maxlen fields of the ctl_table 1291 * struct enable minimal validation of the values being written to be 1292 * performed, and the mode field allows minimal authentication. 1293 * 1294 * More sophisticated management can be enabled by the provision of a 1295 * strategy routine with the table entry. This will be called before 1296 * any automatic read or write of the data is performed. 1297 * 1298 * The strategy routine may return 1299 * 1300 * < 0 - Error occurred (error is passed to user process) 1301 * 1302 * 0 - OK - proceed with automatic read or write. 1303 * 1304 * > 0 - OK - read or write has been done by the strategy routine, so 1305 * return immediately. 1306 * 1307 * There must be a proc_handler routine for any terminal nodes 1308 * mirrored under /proc/sys (non-terminals are handled by a built-in 1309 * directory handler). Several default handlers are available to 1310 * cover common cases - 1311 * 1312 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), 1313 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 1314 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() 1315 * 1316 * It is the handler's job to read the input buffer from user memory 1317 * and process it. The handler should return 0 on success. 1318 * 1319 * This routine returns %NULL on a failure to register, and a pointer 1320 * to the table header on success. 1321 */ 1322 struct ctl_table_header *register_sysctl_table(ctl_table * table, 1323 int insert_at_head) 1324 { 1325 struct ctl_table_header *tmp; 1326 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); 1327 if (!tmp) 1328 return NULL; 1329 tmp->ctl_table = table; 1330 INIT_LIST_HEAD(&tmp->ctl_entry); 1331 tmp->used = 0; 1332 tmp->unregistering = NULL; 1333 spin_lock(&sysctl_lock); 1334 if (insert_at_head) 1335 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry); 1336 else 1337 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); 1338 spin_unlock(&sysctl_lock); 1339 #ifdef CONFIG_PROC_FS 1340 register_proc_table(table, proc_sys_root, tmp); 1341 #endif 1342 return tmp; 1343 } 1344 1345 /** 1346 * unregister_sysctl_table - unregister a sysctl table hierarchy 1347 * @header: the header returned from register_sysctl_table 1348 * 1349 * Unregisters the sysctl table and all children. proc entries may not 1350 * actually be removed until they are no longer used by anyone. 1351 */ 1352 void unregister_sysctl_table(struct ctl_table_header * header) 1353 { 1354 might_sleep(); 1355 spin_lock(&sysctl_lock); 1356 start_unregistering(header); 1357 #ifdef CONFIG_PROC_FS 1358 unregister_proc_table(header->ctl_table, proc_sys_root); 1359 #endif 1360 spin_unlock(&sysctl_lock); 1361 kfree(header); 1362 } 1363 1364 /* 1365 * /proc/sys support 1366 */ 1367 1368 #ifdef CONFIG_PROC_FS 1369 1370 /* Scan the sysctl entries in table and add them all into /proc */ 1371 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set) 1372 { 1373 struct proc_dir_entry *de; 1374 int len; 1375 mode_t mode; 1376 1377 for (; table->ctl_name; table++) { 1378 /* Can't do anything without a proc name. */ 1379 if (!table->procname) 1380 continue; 1381 /* Maybe we can't do anything with it... */ 1382 if (!table->proc_handler && !table->child) { 1383 printk(KERN_WARNING "SYSCTL: Can't register %s\n", 1384 table->procname); 1385 continue; 1386 } 1387 1388 len = strlen(table->procname); 1389 mode = table->mode; 1390 1391 de = NULL; 1392 if (table->proc_handler) 1393 mode |= S_IFREG; 1394 else { 1395 mode |= S_IFDIR; 1396 for (de = root->subdir; de; de = de->next) { 1397 if (proc_match(len, table->procname, de)) 1398 break; 1399 } 1400 /* If the subdir exists already, de is non-NULL */ 1401 } 1402 1403 if (!de) { 1404 de = create_proc_entry(table->procname, mode, root); 1405 if (!de) 1406 continue; 1407 de->set = set; 1408 de->data = (void *) table; 1409 if (table->proc_handler) 1410 de->proc_fops = &proc_sys_file_operations; 1411 } 1412 table->de = de; 1413 if (de->mode & S_IFDIR) 1414 register_proc_table(table->child, de, set); 1415 } 1416 } 1417 1418 /* 1419 * Unregister a /proc sysctl table and any subdirectories. 1420 */ 1421 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root) 1422 { 1423 struct proc_dir_entry *de; 1424 for (; table->ctl_name; table++) { 1425 if (!(de = table->de)) 1426 continue; 1427 if (de->mode & S_IFDIR) { 1428 if (!table->child) { 1429 printk (KERN_ALERT "Help - malformed sysctl tree on free\n"); 1430 continue; 1431 } 1432 unregister_proc_table(table->child, de); 1433 1434 /* Don't unregister directories which still have entries.. */ 1435 if (de->subdir) 1436 continue; 1437 } 1438 1439 /* 1440 * In any case, mark the entry as goner; we'll keep it 1441 * around if it's busy, but we'll know to do nothing with 1442 * its fields. We are under sysctl_lock here. 1443 */ 1444 de->data = NULL; 1445 1446 /* Don't unregister proc entries that are still being used.. */ 1447 if (atomic_read(&de->count)) 1448 continue; 1449 1450 table->de = NULL; 1451 remove_proc_entry(table->procname, root); 1452 } 1453 } 1454 1455 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf, 1456 size_t count, loff_t *ppos) 1457 { 1458 int op; 1459 struct proc_dir_entry *de = PDE(file->f_dentry->d_inode); 1460 struct ctl_table *table; 1461 size_t res; 1462 ssize_t error = -ENOTDIR; 1463 1464 spin_lock(&sysctl_lock); 1465 if (de && de->data && use_table(de->set)) { 1466 /* 1467 * at that point we know that sysctl was not unregistered 1468 * and won't be until we finish 1469 */ 1470 spin_unlock(&sysctl_lock); 1471 table = (struct ctl_table *) de->data; 1472 if (!table || !table->proc_handler) 1473 goto out; 1474 error = -EPERM; 1475 op = (write ? 002 : 004); 1476 if (ctl_perm(table, op)) 1477 goto out; 1478 1479 /* careful: calling conventions are nasty here */ 1480 res = count; 1481 error = (*table->proc_handler)(table, write, file, 1482 buf, &res, ppos); 1483 if (!error) 1484 error = res; 1485 out: 1486 spin_lock(&sysctl_lock); 1487 unuse_table(de->set); 1488 } 1489 spin_unlock(&sysctl_lock); 1490 return error; 1491 } 1492 1493 static int proc_opensys(struct inode *inode, struct file *file) 1494 { 1495 if (file->f_mode & FMODE_WRITE) { 1496 /* 1497 * sysctl entries that are not writable, 1498 * are _NOT_ writable, capabilities or not. 1499 */ 1500 if (!(inode->i_mode & S_IWUSR)) 1501 return -EPERM; 1502 } 1503 1504 return 0; 1505 } 1506 1507 static ssize_t proc_readsys(struct file * file, char __user * buf, 1508 size_t count, loff_t *ppos) 1509 { 1510 return do_rw_proc(0, file, buf, count, ppos); 1511 } 1512 1513 static ssize_t proc_writesys(struct file * file, const char __user * buf, 1514 size_t count, loff_t *ppos) 1515 { 1516 return do_rw_proc(1, file, (char __user *) buf, count, ppos); 1517 } 1518 1519 /** 1520 * proc_dostring - read a string sysctl 1521 * @table: the sysctl table 1522 * @write: %TRUE if this is a write to the sysctl file 1523 * @filp: the file structure 1524 * @buffer: the user buffer 1525 * @lenp: the size of the user buffer 1526 * @ppos: file position 1527 * 1528 * Reads/writes a string from/to the user buffer. If the kernel 1529 * buffer provided is not large enough to hold the string, the 1530 * string is truncated. The copied string is %NULL-terminated. 1531 * If the string is being read by the user process, it is copied 1532 * and a newline '\n' is added. It is truncated if the buffer is 1533 * not large enough. 1534 * 1535 * Returns 0 on success. 1536 */ 1537 int proc_dostring(ctl_table *table, int write, struct file *filp, 1538 void __user *buffer, size_t *lenp, loff_t *ppos) 1539 { 1540 size_t len; 1541 char __user *p; 1542 char c; 1543 1544 if (!table->data || !table->maxlen || !*lenp || 1545 (*ppos && !write)) { 1546 *lenp = 0; 1547 return 0; 1548 } 1549 1550 if (write) { 1551 len = 0; 1552 p = buffer; 1553 while (len < *lenp) { 1554 if (get_user(c, p++)) 1555 return -EFAULT; 1556 if (c == 0 || c == '\n') 1557 break; 1558 len++; 1559 } 1560 if (len >= table->maxlen) 1561 len = table->maxlen-1; 1562 if(copy_from_user(table->data, buffer, len)) 1563 return -EFAULT; 1564 ((char *) table->data)[len] = 0; 1565 *ppos += *lenp; 1566 } else { 1567 len = strlen(table->data); 1568 if (len > table->maxlen) 1569 len = table->maxlen; 1570 if (len > *lenp) 1571 len = *lenp; 1572 if (len) 1573 if(copy_to_user(buffer, table->data, len)) 1574 return -EFAULT; 1575 if (len < *lenp) { 1576 if(put_user('\n', ((char __user *) buffer) + len)) 1577 return -EFAULT; 1578 len++; 1579 } 1580 *lenp = len; 1581 *ppos += len; 1582 } 1583 return 0; 1584 } 1585 1586 /* 1587 * Special case of dostring for the UTS structure. This has locks 1588 * to observe. Should this be in kernel/sys.c ???? 1589 */ 1590 1591 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 1592 void __user *buffer, size_t *lenp, loff_t *ppos) 1593 { 1594 int r; 1595 1596 if (!write) { 1597 down_read(&uts_sem); 1598 r=proc_dostring(table,0,filp,buffer,lenp, ppos); 1599 up_read(&uts_sem); 1600 } else { 1601 down_write(&uts_sem); 1602 r=proc_dostring(table,1,filp,buffer,lenp, ppos); 1603 up_write(&uts_sem); 1604 } 1605 return r; 1606 } 1607 1608 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, 1609 int *valp, 1610 int write, void *data) 1611 { 1612 if (write) { 1613 *valp = *negp ? -*lvalp : *lvalp; 1614 } else { 1615 int val = *valp; 1616 if (val < 0) { 1617 *negp = -1; 1618 *lvalp = (unsigned long)-val; 1619 } else { 1620 *negp = 0; 1621 *lvalp = (unsigned long)val; 1622 } 1623 } 1624 return 0; 1625 } 1626 1627 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp, 1628 void __user *buffer, size_t *lenp, loff_t *ppos, 1629 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1630 int write, void *data), 1631 void *data) 1632 { 1633 #define TMPBUFLEN 21 1634 int *i, vleft, first=1, neg, val; 1635 unsigned long lval; 1636 size_t left, len; 1637 1638 char buf[TMPBUFLEN], *p; 1639 char __user *s = buffer; 1640 1641 if (!table->data || !table->maxlen || !*lenp || 1642 (*ppos && !write)) { 1643 *lenp = 0; 1644 return 0; 1645 } 1646 1647 i = (int *) table->data; 1648 vleft = table->maxlen / sizeof(*i); 1649 left = *lenp; 1650 1651 if (!conv) 1652 conv = do_proc_dointvec_conv; 1653 1654 for (; left && vleft--; i++, first=0) { 1655 if (write) { 1656 while (left) { 1657 char c; 1658 if (get_user(c, s)) 1659 return -EFAULT; 1660 if (!isspace(c)) 1661 break; 1662 left--; 1663 s++; 1664 } 1665 if (!left) 1666 break; 1667 neg = 0; 1668 len = left; 1669 if (len > sizeof(buf) - 1) 1670 len = sizeof(buf) - 1; 1671 if (copy_from_user(buf, s, len)) 1672 return -EFAULT; 1673 buf[len] = 0; 1674 p = buf; 1675 if (*p == '-' && left > 1) { 1676 neg = 1; 1677 left--, p++; 1678 } 1679 if (*p < '0' || *p > '9') 1680 break; 1681 1682 lval = simple_strtoul(p, &p, 0); 1683 1684 len = p-buf; 1685 if ((len < left) && *p && !isspace(*p)) 1686 break; 1687 if (neg) 1688 val = -val; 1689 s += len; 1690 left -= len; 1691 1692 if (conv(&neg, &lval, i, 1, data)) 1693 break; 1694 } else { 1695 p = buf; 1696 if (!first) 1697 *p++ = '\t'; 1698 1699 if (conv(&neg, &lval, i, 0, data)) 1700 break; 1701 1702 sprintf(p, "%s%lu", neg ? "-" : "", lval); 1703 len = strlen(buf); 1704 if (len > left) 1705 len = left; 1706 if(copy_to_user(s, buf, len)) 1707 return -EFAULT; 1708 left -= len; 1709 s += len; 1710 } 1711 } 1712 1713 if (!write && !first && left) { 1714 if(put_user('\n', s)) 1715 return -EFAULT; 1716 left--, s++; 1717 } 1718 if (write) { 1719 while (left) { 1720 char c; 1721 if (get_user(c, s++)) 1722 return -EFAULT; 1723 if (!isspace(c)) 1724 break; 1725 left--; 1726 } 1727 } 1728 if (write && first) 1729 return -EINVAL; 1730 *lenp -= left; 1731 *ppos += *lenp; 1732 return 0; 1733 #undef TMPBUFLEN 1734 } 1735 1736 /** 1737 * proc_dointvec - read a vector of integers 1738 * @table: the sysctl table 1739 * @write: %TRUE if this is a write to the sysctl file 1740 * @filp: the file structure 1741 * @buffer: the user buffer 1742 * @lenp: the size of the user buffer 1743 * @ppos: file position 1744 * 1745 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1746 * values from/to the user buffer, treated as an ASCII string. 1747 * 1748 * Returns 0 on success. 1749 */ 1750 int proc_dointvec(ctl_table *table, int write, struct file *filp, 1751 void __user *buffer, size_t *lenp, loff_t *ppos) 1752 { 1753 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1754 NULL,NULL); 1755 } 1756 1757 #define OP_SET 0 1758 #define OP_AND 1 1759 #define OP_OR 2 1760 #define OP_MAX 3 1761 #define OP_MIN 4 1762 1763 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, 1764 int *valp, 1765 int write, void *data) 1766 { 1767 int op = *(int *)data; 1768 if (write) { 1769 int val = *negp ? -*lvalp : *lvalp; 1770 switch(op) { 1771 case OP_SET: *valp = val; break; 1772 case OP_AND: *valp &= val; break; 1773 case OP_OR: *valp |= val; break; 1774 case OP_MAX: if(*valp < val) 1775 *valp = val; 1776 break; 1777 case OP_MIN: if(*valp > val) 1778 *valp = val; 1779 break; 1780 } 1781 } else { 1782 int val = *valp; 1783 if (val < 0) { 1784 *negp = -1; 1785 *lvalp = (unsigned long)-val; 1786 } else { 1787 *negp = 0; 1788 *lvalp = (unsigned long)val; 1789 } 1790 } 1791 return 0; 1792 } 1793 1794 /* 1795 * init may raise the set. 1796 */ 1797 1798 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 1799 void __user *buffer, size_t *lenp, loff_t *ppos) 1800 { 1801 int op; 1802 1803 if (!capable(CAP_SYS_MODULE)) { 1804 return -EPERM; 1805 } 1806 1807 op = (current->pid == 1) ? OP_SET : OP_AND; 1808 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1809 do_proc_dointvec_bset_conv,&op); 1810 } 1811 1812 struct do_proc_dointvec_minmax_conv_param { 1813 int *min; 1814 int *max; 1815 }; 1816 1817 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 1818 int *valp, 1819 int write, void *data) 1820 { 1821 struct do_proc_dointvec_minmax_conv_param *param = data; 1822 if (write) { 1823 int val = *negp ? -*lvalp : *lvalp; 1824 if ((param->min && *param->min > val) || 1825 (param->max && *param->max < val)) 1826 return -EINVAL; 1827 *valp = val; 1828 } else { 1829 int val = *valp; 1830 if (val < 0) { 1831 *negp = -1; 1832 *lvalp = (unsigned long)-val; 1833 } else { 1834 *negp = 0; 1835 *lvalp = (unsigned long)val; 1836 } 1837 } 1838 return 0; 1839 } 1840 1841 /** 1842 * proc_dointvec_minmax - read a vector of integers with min/max values 1843 * @table: the sysctl table 1844 * @write: %TRUE if this is a write to the sysctl file 1845 * @filp: the file structure 1846 * @buffer: the user buffer 1847 * @lenp: the size of the user buffer 1848 * @ppos: file position 1849 * 1850 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1851 * values from/to the user buffer, treated as an ASCII string. 1852 * 1853 * This routine will ensure the values are within the range specified by 1854 * table->extra1 (min) and table->extra2 (max). 1855 * 1856 * Returns 0 on success. 1857 */ 1858 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 1859 void __user *buffer, size_t *lenp, loff_t *ppos) 1860 { 1861 struct do_proc_dointvec_minmax_conv_param param = { 1862 .min = (int *) table->extra1, 1863 .max = (int *) table->extra2, 1864 }; 1865 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 1866 do_proc_dointvec_minmax_conv, ¶m); 1867 } 1868 1869 static int do_proc_doulongvec_minmax(ctl_table *table, int write, 1870 struct file *filp, 1871 void __user *buffer, 1872 size_t *lenp, loff_t *ppos, 1873 unsigned long convmul, 1874 unsigned long convdiv) 1875 { 1876 #define TMPBUFLEN 21 1877 unsigned long *i, *min, *max, val; 1878 int vleft, first=1, neg; 1879 size_t len, left; 1880 char buf[TMPBUFLEN], *p; 1881 char __user *s = buffer; 1882 1883 if (!table->data || !table->maxlen || !*lenp || 1884 (*ppos && !write)) { 1885 *lenp = 0; 1886 return 0; 1887 } 1888 1889 i = (unsigned long *) table->data; 1890 min = (unsigned long *) table->extra1; 1891 max = (unsigned long *) table->extra2; 1892 vleft = table->maxlen / sizeof(unsigned long); 1893 left = *lenp; 1894 1895 for (; left && vleft--; i++, min++, max++, first=0) { 1896 if (write) { 1897 while (left) { 1898 char c; 1899 if (get_user(c, s)) 1900 return -EFAULT; 1901 if (!isspace(c)) 1902 break; 1903 left--; 1904 s++; 1905 } 1906 if (!left) 1907 break; 1908 neg = 0; 1909 len = left; 1910 if (len > TMPBUFLEN-1) 1911 len = TMPBUFLEN-1; 1912 if (copy_from_user(buf, s, len)) 1913 return -EFAULT; 1914 buf[len] = 0; 1915 p = buf; 1916 if (*p == '-' && left > 1) { 1917 neg = 1; 1918 left--, p++; 1919 } 1920 if (*p < '0' || *p > '9') 1921 break; 1922 val = simple_strtoul(p, &p, 0) * convmul / convdiv ; 1923 len = p-buf; 1924 if ((len < left) && *p && !isspace(*p)) 1925 break; 1926 if (neg) 1927 val = -val; 1928 s += len; 1929 left -= len; 1930 1931 if(neg) 1932 continue; 1933 if ((min && val < *min) || (max && val > *max)) 1934 continue; 1935 *i = val; 1936 } else { 1937 p = buf; 1938 if (!first) 1939 *p++ = '\t'; 1940 sprintf(p, "%lu", convdiv * (*i) / convmul); 1941 len = strlen(buf); 1942 if (len > left) 1943 len = left; 1944 if(copy_to_user(s, buf, len)) 1945 return -EFAULT; 1946 left -= len; 1947 s += len; 1948 } 1949 } 1950 1951 if (!write && !first && left) { 1952 if(put_user('\n', s)) 1953 return -EFAULT; 1954 left--, s++; 1955 } 1956 if (write) { 1957 while (left) { 1958 char c; 1959 if (get_user(c, s++)) 1960 return -EFAULT; 1961 if (!isspace(c)) 1962 break; 1963 left--; 1964 } 1965 } 1966 if (write && first) 1967 return -EINVAL; 1968 *lenp -= left; 1969 *ppos += *lenp; 1970 return 0; 1971 #undef TMPBUFLEN 1972 } 1973 1974 /** 1975 * proc_doulongvec_minmax - read a vector of long integers with min/max values 1976 * @table: the sysctl table 1977 * @write: %TRUE if this is a write to the sysctl file 1978 * @filp: the file structure 1979 * @buffer: the user buffer 1980 * @lenp: the size of the user buffer 1981 * @ppos: file position 1982 * 1983 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 1984 * values from/to the user buffer, treated as an ASCII string. 1985 * 1986 * This routine will ensure the values are within the range specified by 1987 * table->extra1 (min) and table->extra2 (max). 1988 * 1989 * Returns 0 on success. 1990 */ 1991 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 1992 void __user *buffer, size_t *lenp, loff_t *ppos) 1993 { 1994 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l); 1995 } 1996 1997 /** 1998 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values 1999 * @table: the sysctl table 2000 * @write: %TRUE if this is a write to the sysctl file 2001 * @filp: the file structure 2002 * @buffer: the user buffer 2003 * @lenp: the size of the user buffer 2004 * @ppos: file position 2005 * 2006 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2007 * values from/to the user buffer, treated as an ASCII string. The values 2008 * are treated as milliseconds, and converted to jiffies when they are stored. 2009 * 2010 * This routine will ensure the values are within the range specified by 2011 * table->extra1 (min) and table->extra2 (max). 2012 * 2013 * Returns 0 on success. 2014 */ 2015 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2016 struct file *filp, 2017 void __user *buffer, 2018 size_t *lenp, loff_t *ppos) 2019 { 2020 return do_proc_doulongvec_minmax(table, write, filp, buffer, 2021 lenp, ppos, HZ, 1000l); 2022 } 2023 2024 2025 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp, 2026 int *valp, 2027 int write, void *data) 2028 { 2029 if (write) { 2030 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); 2031 } else { 2032 int val = *valp; 2033 unsigned long lval; 2034 if (val < 0) { 2035 *negp = -1; 2036 lval = (unsigned long)-val; 2037 } else { 2038 *negp = 0; 2039 lval = (unsigned long)val; 2040 } 2041 *lvalp = lval / HZ; 2042 } 2043 return 0; 2044 } 2045 2046 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp, 2047 int *valp, 2048 int write, void *data) 2049 { 2050 if (write) { 2051 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp); 2052 } else { 2053 int val = *valp; 2054 unsigned long lval; 2055 if (val < 0) { 2056 *negp = -1; 2057 lval = (unsigned long)-val; 2058 } else { 2059 *negp = 0; 2060 lval = (unsigned long)val; 2061 } 2062 *lvalp = jiffies_to_clock_t(lval); 2063 } 2064 return 0; 2065 } 2066 2067 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp, 2068 int *valp, 2069 int write, void *data) 2070 { 2071 if (write) { 2072 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); 2073 } else { 2074 int val = *valp; 2075 unsigned long lval; 2076 if (val < 0) { 2077 *negp = -1; 2078 lval = (unsigned long)-val; 2079 } else { 2080 *negp = 0; 2081 lval = (unsigned long)val; 2082 } 2083 *lvalp = jiffies_to_msecs(lval); 2084 } 2085 return 0; 2086 } 2087 2088 /** 2089 * proc_dointvec_jiffies - read a vector of integers as seconds 2090 * @table: the sysctl table 2091 * @write: %TRUE if this is a write to the sysctl file 2092 * @filp: the file structure 2093 * @buffer: the user buffer 2094 * @lenp: the size of the user buffer 2095 * @ppos: file position 2096 * 2097 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2098 * values from/to the user buffer, treated as an ASCII string. 2099 * The values read are assumed to be in seconds, and are converted into 2100 * jiffies. 2101 * 2102 * Returns 0 on success. 2103 */ 2104 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2105 void __user *buffer, size_t *lenp, loff_t *ppos) 2106 { 2107 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2108 do_proc_dointvec_jiffies_conv,NULL); 2109 } 2110 2111 /** 2112 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds 2113 * @table: the sysctl table 2114 * @write: %TRUE if this is a write to the sysctl file 2115 * @filp: the file structure 2116 * @buffer: the user buffer 2117 * @lenp: the size of the user buffer 2118 * @ppos: pointer to the file position 2119 * 2120 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2121 * values from/to the user buffer, treated as an ASCII string. 2122 * The values read are assumed to be in 1/USER_HZ seconds, and 2123 * are converted into jiffies. 2124 * 2125 * Returns 0 on success. 2126 */ 2127 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2128 void __user *buffer, size_t *lenp, loff_t *ppos) 2129 { 2130 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2131 do_proc_dointvec_userhz_jiffies_conv,NULL); 2132 } 2133 2134 /** 2135 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds 2136 * @table: the sysctl table 2137 * @write: %TRUE if this is a write to the sysctl file 2138 * @filp: the file structure 2139 * @buffer: the user buffer 2140 * @lenp: the size of the user buffer 2141 * @ppos: file position 2142 * @ppos: the current position in the file 2143 * 2144 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2145 * values from/to the user buffer, treated as an ASCII string. 2146 * The values read are assumed to be in 1/1000 seconds, and 2147 * are converted into jiffies. 2148 * 2149 * Returns 0 on success. 2150 */ 2151 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2152 void __user *buffer, size_t *lenp, loff_t *ppos) 2153 { 2154 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2155 do_proc_dointvec_ms_jiffies_conv, NULL); 2156 } 2157 2158 #else /* CONFIG_PROC_FS */ 2159 2160 int proc_dostring(ctl_table *table, int write, struct file *filp, 2161 void __user *buffer, size_t *lenp, loff_t *ppos) 2162 { 2163 return -ENOSYS; 2164 } 2165 2166 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 2167 void __user *buffer, size_t *lenp, loff_t *ppos) 2168 { 2169 return -ENOSYS; 2170 } 2171 2172 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2173 void __user *buffer, size_t *lenp, loff_t *ppos) 2174 { 2175 return -ENOSYS; 2176 } 2177 2178 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2179 void __user *buffer, size_t *lenp, loff_t *ppos) 2180 { 2181 return -ENOSYS; 2182 } 2183 2184 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2185 void __user *buffer, size_t *lenp, loff_t *ppos) 2186 { 2187 return -ENOSYS; 2188 } 2189 2190 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2191 void __user *buffer, size_t *lenp, loff_t *ppos) 2192 { 2193 return -ENOSYS; 2194 } 2195 2196 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2197 void __user *buffer, size_t *lenp, loff_t *ppos) 2198 { 2199 return -ENOSYS; 2200 } 2201 2202 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2203 void __user *buffer, size_t *lenp, loff_t *ppos) 2204 { 2205 return -ENOSYS; 2206 } 2207 2208 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2209 void __user *buffer, size_t *lenp, loff_t *ppos) 2210 { 2211 return -ENOSYS; 2212 } 2213 2214 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2215 struct file *filp, 2216 void __user *buffer, 2217 size_t *lenp, loff_t *ppos) 2218 { 2219 return -ENOSYS; 2220 } 2221 2222 2223 #endif /* CONFIG_PROC_FS */ 2224 2225 2226 /* 2227 * General sysctl support routines 2228 */ 2229 2230 /* The generic string strategy routine: */ 2231 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2232 void __user *oldval, size_t __user *oldlenp, 2233 void __user *newval, size_t newlen, void **context) 2234 { 2235 if (!table->data || !table->maxlen) 2236 return -ENOTDIR; 2237 2238 if (oldval && oldlenp) { 2239 size_t bufsize; 2240 if (get_user(bufsize, oldlenp)) 2241 return -EFAULT; 2242 if (bufsize) { 2243 size_t len = strlen(table->data), copied; 2244 2245 /* This shouldn't trigger for a well-formed sysctl */ 2246 if (len > table->maxlen) 2247 len = table->maxlen; 2248 2249 /* Copy up to a max of bufsize-1 bytes of the string */ 2250 copied = (len >= bufsize) ? bufsize - 1 : len; 2251 2252 if (copy_to_user(oldval, table->data, copied) || 2253 put_user(0, (char __user *)(oldval + copied))) 2254 return -EFAULT; 2255 if (put_user(len, oldlenp)) 2256 return -EFAULT; 2257 } 2258 } 2259 if (newval && newlen) { 2260 size_t len = newlen; 2261 if (len > table->maxlen) 2262 len = table->maxlen; 2263 if(copy_from_user(table->data, newval, len)) 2264 return -EFAULT; 2265 if (len == table->maxlen) 2266 len--; 2267 ((char *) table->data)[len] = 0; 2268 } 2269 return 1; 2270 } 2271 2272 /* 2273 * This function makes sure that all of the integers in the vector 2274 * are between the minimum and maximum values given in the arrays 2275 * table->extra1 and table->extra2, respectively. 2276 */ 2277 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2278 void __user *oldval, size_t __user *oldlenp, 2279 void __user *newval, size_t newlen, void **context) 2280 { 2281 2282 if (newval && newlen) { 2283 int __user *vec = (int __user *) newval; 2284 int *min = (int *) table->extra1; 2285 int *max = (int *) table->extra2; 2286 size_t length; 2287 int i; 2288 2289 if (newlen % sizeof(int) != 0) 2290 return -EINVAL; 2291 2292 if (!table->extra1 && !table->extra2) 2293 return 0; 2294 2295 if (newlen > table->maxlen) 2296 newlen = table->maxlen; 2297 length = newlen / sizeof(int); 2298 2299 for (i = 0; i < length; i++) { 2300 int value; 2301 if (get_user(value, vec + i)) 2302 return -EFAULT; 2303 if (min && value < min[i]) 2304 return -EINVAL; 2305 if (max && value > max[i]) 2306 return -EINVAL; 2307 } 2308 } 2309 return 0; 2310 } 2311 2312 /* Strategy function to convert jiffies to seconds */ 2313 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2314 void __user *oldval, size_t __user *oldlenp, 2315 void __user *newval, size_t newlen, void **context) 2316 { 2317 if (oldval) { 2318 size_t olen; 2319 if (oldlenp) { 2320 if (get_user(olen, oldlenp)) 2321 return -EFAULT; 2322 if (olen!=sizeof(int)) 2323 return -EINVAL; 2324 } 2325 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) || 2326 (oldlenp && put_user(sizeof(int),oldlenp))) 2327 return -EFAULT; 2328 } 2329 if (newval && newlen) { 2330 int new; 2331 if (newlen != sizeof(int)) 2332 return -EINVAL; 2333 if (get_user(new, (int __user *)newval)) 2334 return -EFAULT; 2335 *(int *)(table->data) = new*HZ; 2336 } 2337 return 1; 2338 } 2339 2340 /* Strategy function to convert jiffies to seconds */ 2341 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2342 void __user *oldval, size_t __user *oldlenp, 2343 void __user *newval, size_t newlen, void **context) 2344 { 2345 if (oldval) { 2346 size_t olen; 2347 if (oldlenp) { 2348 if (get_user(olen, oldlenp)) 2349 return -EFAULT; 2350 if (olen!=sizeof(int)) 2351 return -EINVAL; 2352 } 2353 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) || 2354 (oldlenp && put_user(sizeof(int),oldlenp))) 2355 return -EFAULT; 2356 } 2357 if (newval && newlen) { 2358 int new; 2359 if (newlen != sizeof(int)) 2360 return -EINVAL; 2361 if (get_user(new, (int __user *)newval)) 2362 return -EFAULT; 2363 *(int *)(table->data) = msecs_to_jiffies(new); 2364 } 2365 return 1; 2366 } 2367 2368 #else /* CONFIG_SYSCTL */ 2369 2370 2371 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 2372 { 2373 return -ENOSYS; 2374 } 2375 2376 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2377 void __user *oldval, size_t __user *oldlenp, 2378 void __user *newval, size_t newlen, void **context) 2379 { 2380 return -ENOSYS; 2381 } 2382 2383 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2384 void __user *oldval, size_t __user *oldlenp, 2385 void __user *newval, size_t newlen, void **context) 2386 { 2387 return -ENOSYS; 2388 } 2389 2390 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2391 void __user *oldval, size_t __user *oldlenp, 2392 void __user *newval, size_t newlen, void **context) 2393 { 2394 return -ENOSYS; 2395 } 2396 2397 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2398 void __user *oldval, size_t __user *oldlenp, 2399 void __user *newval, size_t newlen, void **context) 2400 { 2401 return -ENOSYS; 2402 } 2403 2404 int proc_dostring(ctl_table *table, int write, struct file *filp, 2405 void __user *buffer, size_t *lenp, loff_t *ppos) 2406 { 2407 return -ENOSYS; 2408 } 2409 2410 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2411 void __user *buffer, size_t *lenp, loff_t *ppos) 2412 { 2413 return -ENOSYS; 2414 } 2415 2416 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2417 void __user *buffer, size_t *lenp, loff_t *ppos) 2418 { 2419 return -ENOSYS; 2420 } 2421 2422 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2423 void __user *buffer, size_t *lenp, loff_t *ppos) 2424 { 2425 return -ENOSYS; 2426 } 2427 2428 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2429 void __user *buffer, size_t *lenp, loff_t *ppos) 2430 { 2431 return -ENOSYS; 2432 } 2433 2434 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2435 void __user *buffer, size_t *lenp, loff_t *ppos) 2436 { 2437 return -ENOSYS; 2438 } 2439 2440 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2441 void __user *buffer, size_t *lenp, loff_t *ppos) 2442 { 2443 return -ENOSYS; 2444 } 2445 2446 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2447 void __user *buffer, size_t *lenp, loff_t *ppos) 2448 { 2449 return -ENOSYS; 2450 } 2451 2452 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2453 struct file *filp, 2454 void __user *buffer, 2455 size_t *lenp, loff_t *ppos) 2456 { 2457 return -ENOSYS; 2458 } 2459 2460 struct ctl_table_header * register_sysctl_table(ctl_table * table, 2461 int insert_at_head) 2462 { 2463 return NULL; 2464 } 2465 2466 void unregister_sysctl_table(struct ctl_table_header * table) 2467 { 2468 } 2469 2470 #endif /* CONFIG_SYSCTL */ 2471 2472 /* 2473 * No sense putting this after each symbol definition, twice, 2474 * exception granted :-) 2475 */ 2476 EXPORT_SYMBOL(proc_dointvec); 2477 EXPORT_SYMBOL(proc_dointvec_jiffies); 2478 EXPORT_SYMBOL(proc_dointvec_minmax); 2479 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); 2480 EXPORT_SYMBOL(proc_dointvec_ms_jiffies); 2481 EXPORT_SYMBOL(proc_dostring); 2482 EXPORT_SYMBOL(proc_doulongvec_minmax); 2483 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); 2484 EXPORT_SYMBOL(register_sysctl_table); 2485 EXPORT_SYMBOL(sysctl_intvec); 2486 EXPORT_SYMBOL(sysctl_jiffies); 2487 EXPORT_SYMBOL(sysctl_ms_jiffies); 2488 EXPORT_SYMBOL(sysctl_string); 2489 EXPORT_SYMBOL(unregister_sysctl_table); 2490