1/* Modified by Broadcom Corp. Portions Copyright (c) Broadcom Corp, 2012. */ 2/* 3 Copyright (C) 2002 Richard Henderson 4 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19*/ 20#include <linux/module.h> 21#include <linux/moduleloader.h> 22#include <linux/ftrace_event.h> 23#include <linux/init.h> 24#include <linux/kallsyms.h> 25#include <linux/fs.h> 26#include <linux/sysfs.h> 27#include <linux/kernel.h> 28#include <linux/slab.h> 29#include <linux/vmalloc.h> 30#include <linux/elf.h> 31#include <linux/proc_fs.h> 32#include <linux/seq_file.h> 33#include <linux/syscalls.h> 34#include <linux/fcntl.h> 35#include <linux/rcupdate.h> 36#include <linux/capability.h> 37#include <linux/cpu.h> 38#include <linux/moduleparam.h> 39#include <linux/errno.h> 40#include <linux/err.h> 41#include <linux/vermagic.h> 42#include <linux/notifier.h> 43#include <linux/sched.h> 44#include <linux/stop_machine.h> 45#include <linux/device.h> 46#include <linux/string.h> 47#include <linux/mutex.h> 48#include <linux/rculist.h> 49#include <asm/uaccess.h> 50#include <asm/cacheflush.h> 51#include <asm/mmu_context.h> 52#include <linux/license.h> 53#include <asm/sections.h> 54#include <linux/tracepoint.h> 55#include <linux/ftrace.h> 56#include <linux/async.h> 57#include <linux/percpu.h> 58#include <linux/kmemleak.h> 59 60#define CREATE_TRACE_POINTS 61#include <trace/events/module.h> 62 63#define DEBUGP(fmt , a...) 64 65#ifndef ARCH_SHF_SMALL 66#define ARCH_SHF_SMALL 0 67#endif 68 69/* If this is set, the section belongs in the init part of the module */ 70#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) 71 72/* 73 * Mutex protects: 74 * 1) List of modules (also safely readable with preempt_disable), 75 * 2) module_use links, 76 * 3) module_addr_min/module_addr_max. 77 * (delete uses stop_machine/add uses RCU list operations). */ 78DEFINE_MUTEX(module_mutex); 79EXPORT_SYMBOL_GPL(module_mutex); 80static LIST_HEAD(modules); 81#ifdef CONFIG_KGDB_KDB 82struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ 83#endif /* CONFIG_KGDB_KDB */ 84 85 86/* Block module loading/unloading? */ 87int modules_disabled = 0; 88 89/* Waiting for a module to finish initializing? */ 90static DECLARE_WAIT_QUEUE_HEAD(module_wq); 91 92static BLOCKING_NOTIFIER_HEAD(module_notify_list); 93 94/* Bounds of module allocation, for speeding __module_address. 95 * Protected by module_mutex. */ 96static unsigned long module_addr_min = -1UL, module_addr_max = 0; 97 98int register_module_notifier(struct notifier_block * nb) 99{ 100 return blocking_notifier_chain_register(&module_notify_list, nb); 101} 102EXPORT_SYMBOL(register_module_notifier); 103 104int unregister_module_notifier(struct notifier_block * nb) 105{ 106 return blocking_notifier_chain_unregister(&module_notify_list, nb); 107} 108EXPORT_SYMBOL(unregister_module_notifier); 109 110struct load_info { 111 Elf_Ehdr *hdr; 112 unsigned long len; 113 Elf_Shdr *sechdrs; 114 char *secstrings, *strtab; 115 unsigned long *strmap; 116 unsigned long symoffs, stroffs; 117 struct _ddebug *debug; 118 unsigned int num_debug; 119 struct { 120 unsigned int sym, str, mod, vers, info, pcpu; 121 } index; 122}; 123 124/* We require a truly strong try_module_get(): 0 means failure due to 125 ongoing or failed initialization etc. */ 126static inline int strong_try_module_get(struct module *mod) 127{ 128 if (mod && mod->state == MODULE_STATE_COMING) 129 return -EBUSY; 130 if (try_module_get(mod)) 131 return 0; 132 else 133 return -ENOENT; 134} 135 136static inline void add_taint_module(struct module *mod, unsigned flag) 137{ 138 add_taint(flag); 139 mod->taints |= (1U << flag); 140} 141 142/* 143 * A thread that wants to hold a reference to a module only while it 144 * is running can call this to safely exit. nfsd and lockd use this. 145 */ 146void __module_put_and_exit(struct module *mod, long code) 147{ 148 module_put(mod); 149 do_exit(code); 150} 151EXPORT_SYMBOL(__module_put_and_exit); 152 153/* Find a module section: 0 means not found. */ 154static unsigned int find_sec(const struct load_info *info, const char *name) 155{ 156 unsigned int i; 157 158 for (i = 1; i < info->hdr->e_shnum; i++) { 159 Elf_Shdr *shdr = &info->sechdrs[i]; 160 /* Alloc bit cleared means "ignore it." */ 161 if ((shdr->sh_flags & SHF_ALLOC) 162 && strcmp(info->secstrings + shdr->sh_name, name) == 0) 163 return i; 164 } 165 return 0; 166} 167 168/* Find a module section, or NULL. */ 169static void *section_addr(const struct load_info *info, const char *name) 170{ 171 /* Section 0 has sh_addr 0. */ 172 return (void *)info->sechdrs[find_sec(info, name)].sh_addr; 173} 174 175/* Find a module section, or NULL. Fill in number of "objects" in section. */ 176static void *section_objs(const struct load_info *info, 177 const char *name, 178 size_t object_size, 179 unsigned int *num) 180{ 181 unsigned int sec = find_sec(info, name); 182 183 /* Section 0 has sh_addr 0 and sh_size 0. */ 184 *num = info->sechdrs[sec].sh_size / object_size; 185 return (void *)info->sechdrs[sec].sh_addr; 186} 187 188/* Provided by the linker */ 189extern const struct kernel_symbol __start___ksymtab[]; 190extern const struct kernel_symbol __stop___ksymtab[]; 191extern const struct kernel_symbol __start___ksymtab_gpl[]; 192extern const struct kernel_symbol __stop___ksymtab_gpl[]; 193extern const struct kernel_symbol __start___ksymtab_gpl_future[]; 194extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; 195extern const unsigned long __start___kcrctab[]; 196extern const unsigned long __start___kcrctab_gpl[]; 197extern const unsigned long __start___kcrctab_gpl_future[]; 198#ifdef CONFIG_UNUSED_SYMBOLS 199extern const struct kernel_symbol __start___ksymtab_unused[]; 200extern const struct kernel_symbol __stop___ksymtab_unused[]; 201extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; 202extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; 203extern const unsigned long __start___kcrctab_unused[]; 204extern const unsigned long __start___kcrctab_unused_gpl[]; 205#endif 206 207#ifndef CONFIG_MODVERSIONS 208#define symversion(base, idx) NULL 209#else 210#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) 211#endif 212 213static bool each_symbol_in_section(const struct symsearch *arr, 214 unsigned int arrsize, 215 struct module *owner, 216 bool (*fn)(const struct symsearch *syms, 217 struct module *owner, 218 unsigned int symnum, void *data), 219 void *data) 220{ 221 unsigned int i, j; 222 223 for (j = 0; j < arrsize; j++) { 224 for (i = 0; i < arr[j].stop - arr[j].start; i++) 225 if (fn(&arr[j], owner, i, data)) 226 return true; 227 } 228 229 return false; 230} 231 232/* Returns true as soon as fn returns true, otherwise false. */ 233bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner, 234 unsigned int symnum, void *data), void *data) 235{ 236 struct module *mod; 237 static const struct symsearch arr[] = { 238 { __start___ksymtab, __stop___ksymtab, __start___kcrctab, 239 NOT_GPL_ONLY, false }, 240 { __start___ksymtab_gpl, __stop___ksymtab_gpl, 241 __start___kcrctab_gpl, 242 GPL_ONLY, false }, 243 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, 244 __start___kcrctab_gpl_future, 245 WILL_BE_GPL_ONLY, false }, 246#ifdef CONFIG_UNUSED_SYMBOLS 247 { __start___ksymtab_unused, __stop___ksymtab_unused, 248 __start___kcrctab_unused, 249 NOT_GPL_ONLY, true }, 250 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, 251 __start___kcrctab_unused_gpl, 252 GPL_ONLY, true }, 253#endif 254 }; 255 256 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) 257 return true; 258 259 list_for_each_entry_rcu(mod, &modules, list) { 260 struct symsearch arr[] = { 261 { mod->syms, mod->syms + mod->num_syms, mod->crcs, 262 NOT_GPL_ONLY, false }, 263 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, 264 mod->gpl_crcs, 265 GPL_ONLY, false }, 266 { mod->gpl_future_syms, 267 mod->gpl_future_syms + mod->num_gpl_future_syms, 268 mod->gpl_future_crcs, 269 WILL_BE_GPL_ONLY, false }, 270#ifdef CONFIG_UNUSED_SYMBOLS 271 { mod->unused_syms, 272 mod->unused_syms + mod->num_unused_syms, 273 mod->unused_crcs, 274 NOT_GPL_ONLY, true }, 275 { mod->unused_gpl_syms, 276 mod->unused_gpl_syms + mod->num_unused_gpl_syms, 277 mod->unused_gpl_crcs, 278 GPL_ONLY, true }, 279#endif 280 }; 281 282 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) 283 return true; 284 } 285 return false; 286} 287EXPORT_SYMBOL_GPL(each_symbol); 288 289struct find_symbol_arg { 290 /* Input */ 291 const char *name; 292 bool gplok; 293 bool warn; 294 295 /* Output */ 296 struct module *owner; 297 const unsigned long *crc; 298 const struct kernel_symbol *sym; 299}; 300 301static bool find_symbol_in_section(const struct symsearch *syms, 302 struct module *owner, 303 unsigned int symnum, void *data) 304{ 305 struct find_symbol_arg *fsa = data; 306 307 if (strcmp(syms->start[symnum].name, fsa->name) != 0) 308 return false; 309 310 if (!fsa->gplok) { 311 if (syms->licence == GPL_ONLY) 312 return false; 313 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { 314 printk(KERN_WARNING "Symbol %s is being used " 315 "by a non-GPL module, which will not " 316 "be allowed in the future\n", fsa->name); 317 printk(KERN_WARNING "Please see the file " 318 "Documentation/feature-removal-schedule.txt " 319 "in the kernel source tree for more details.\n"); 320 } 321 } 322 323#ifdef CONFIG_UNUSED_SYMBOLS 324 if (syms->unused && fsa->warn) { 325 printk(KERN_WARNING "Symbol %s is marked as UNUSED, " 326 "however this module is using it.\n", fsa->name); 327 printk(KERN_WARNING 328 "This symbol will go away in the future.\n"); 329 printk(KERN_WARNING 330 "Please evalute if this is the right api to use and if " 331 "it really is, submit a report the linux kernel " 332 "mailinglist together with submitting your code for " 333 "inclusion.\n"); 334 } 335#endif 336 337 fsa->owner = owner; 338 fsa->crc = symversion(syms->crcs, symnum); 339 fsa->sym = &syms->start[symnum]; 340 return true; 341} 342 343/* Find a symbol and return it, along with, (optional) crc and 344 * (optional) module which owns it. Needs preempt disabled or module_mutex. */ 345const struct kernel_symbol *find_symbol(const char *name, 346 struct module **owner, 347 const unsigned long **crc, 348 bool gplok, 349 bool warn) 350{ 351 struct find_symbol_arg fsa; 352 353 fsa.name = name; 354 fsa.gplok = gplok; 355 fsa.warn = warn; 356 357 if (each_symbol(find_symbol_in_section, &fsa)) { 358 if (owner) 359 *owner = fsa.owner; 360 if (crc) 361 *crc = fsa.crc; 362 return fsa.sym; 363 } 364 365 DEBUGP("Failed to find symbol %s\n", name); 366 return NULL; 367} 368EXPORT_SYMBOL_GPL(find_symbol); 369 370/* Search for module by name: must hold module_mutex. */ 371struct module *find_module(const char *name) 372{ 373 struct module *mod; 374 375 list_for_each_entry(mod, &modules, list) { 376 if (strcmp(mod->name, name) == 0) 377 return mod; 378 } 379 return NULL; 380} 381EXPORT_SYMBOL_GPL(find_module); 382 383#ifdef CONFIG_SMP 384 385static inline void __percpu *mod_percpu(struct module *mod) 386{ 387 return mod->percpu; 388} 389 390static int percpu_modalloc(struct module *mod, 391 unsigned long size, unsigned long align) 392{ 393 if (align > PAGE_SIZE) { 394 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", 395 mod->name, align, PAGE_SIZE); 396 align = PAGE_SIZE; 397 } 398 399 mod->percpu = __alloc_reserved_percpu(size, align); 400 if (!mod->percpu) { 401 printk(KERN_WARNING 402 "%s: Could not allocate %lu bytes percpu data\n", 403 mod->name, size); 404 return -ENOMEM; 405 } 406 mod->percpu_size = size; 407 return 0; 408} 409 410static void percpu_modfree(struct module *mod) 411{ 412 free_percpu(mod->percpu); 413} 414 415static unsigned int find_pcpusec(struct load_info *info) 416{ 417 return find_sec(info, ".data..percpu"); 418} 419 420static void percpu_modcopy(struct module *mod, 421 const void *from, unsigned long size) 422{ 423 int cpu; 424 425 for_each_possible_cpu(cpu) 426 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); 427} 428 429/** 430 * is_module_percpu_address - test whether address is from module static percpu 431 * @addr: address to test 432 * 433 * Test whether @addr belongs to module static percpu area. 434 * 435 * RETURNS: 436 * %true if @addr is from module static percpu area 437 */ 438bool is_module_percpu_address(unsigned long addr) 439{ 440 struct module *mod; 441 unsigned int cpu; 442 443 preempt_disable(); 444 445 list_for_each_entry_rcu(mod, &modules, list) { 446 if (!mod->percpu_size) 447 continue; 448 for_each_possible_cpu(cpu) { 449 void *start = per_cpu_ptr(mod->percpu, cpu); 450 451 if ((void *)addr >= start && 452 (void *)addr < start + mod->percpu_size) { 453 preempt_enable(); 454 return true; 455 } 456 } 457 } 458 459 preempt_enable(); 460 return false; 461} 462 463#else /* ... !CONFIG_SMP */ 464 465static inline void __percpu *mod_percpu(struct module *mod) 466{ 467 return NULL; 468} 469static inline int percpu_modalloc(struct module *mod, 470 unsigned long size, unsigned long align) 471{ 472 return -ENOMEM; 473} 474static inline void percpu_modfree(struct module *mod) 475{ 476} 477static unsigned int find_pcpusec(struct load_info *info) 478{ 479 return 0; 480} 481static inline void percpu_modcopy(struct module *mod, 482 const void *from, unsigned long size) 483{ 484 /* pcpusec should be 0, and size of that section should be 0. */ 485 BUG_ON(size != 0); 486} 487bool is_module_percpu_address(unsigned long addr) 488{ 489 return false; 490} 491 492#endif /* CONFIG_SMP */ 493 494#define MODINFO_ATTR(field) \ 495static void setup_modinfo_##field(struct module *mod, const char *s) \ 496{ \ 497 mod->field = kstrdup(s, GFP_KERNEL); \ 498} \ 499static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ 500 struct module *mod, char *buffer) \ 501{ \ 502 return sprintf(buffer, "%s\n", mod->field); \ 503} \ 504static int modinfo_##field##_exists(struct module *mod) \ 505{ \ 506 return mod->field != NULL; \ 507} \ 508static void free_modinfo_##field(struct module *mod) \ 509{ \ 510 kfree(mod->field); \ 511 mod->field = NULL; \ 512} \ 513static struct module_attribute modinfo_##field = { \ 514 .attr = { .name = __stringify(field), .mode = 0444 }, \ 515 .show = show_modinfo_##field, \ 516 .setup = setup_modinfo_##field, \ 517 .test = modinfo_##field##_exists, \ 518 .free = free_modinfo_##field, \ 519}; 520 521MODINFO_ATTR(version); 522MODINFO_ATTR(srcversion); 523 524static char last_unloaded_module[MODULE_NAME_LEN+1]; 525 526#ifdef CONFIG_MODULE_UNLOAD 527 528EXPORT_TRACEPOINT_SYMBOL(module_get); 529 530/* Init the unload section of the module. */ 531static int module_unload_init(struct module *mod) 532{ 533 mod->refptr = alloc_percpu(struct module_ref); 534 if (!mod->refptr) 535 return -ENOMEM; 536 537 INIT_LIST_HEAD(&mod->source_list); 538 INIT_LIST_HEAD(&mod->target_list); 539 540 /* Hold reference count during initialization. */ 541 __this_cpu_write(mod->refptr->incs, 1); 542 /* Backwards compatibility macros put refcount during init. */ 543 mod->waiter = current; 544 545 return 0; 546} 547 548/* Does a already use b? */ 549static int already_uses(struct module *a, struct module *b) 550{ 551 struct module_use *use; 552 553 list_for_each_entry(use, &b->source_list, source_list) { 554 if (use->source == a) { 555 DEBUGP("%s uses %s!\n", a->name, b->name); 556 return 1; 557 } 558 } 559 DEBUGP("%s does not use %s!\n", a->name, b->name); 560 return 0; 561} 562 563/* 564 * Module a uses b 565 * - we add 'a' as a "source", 'b' as a "target" of module use 566 * - the module_use is added to the list of 'b' sources (so 567 * 'b' can walk the list to see who sourced them), and of 'a' 568 * targets (so 'a' can see what modules it targets). 569 */ 570static int add_module_usage(struct module *a, struct module *b) 571{ 572 struct module_use *use; 573 574 DEBUGP("Allocating new usage for %s.\n", a->name); 575 use = kmalloc(sizeof(*use), GFP_ATOMIC); 576 if (!use) { 577 printk(KERN_WARNING "%s: out of memory loading\n", a->name); 578 return -ENOMEM; 579 } 580 581 use->source = a; 582 use->target = b; 583 list_add(&use->source_list, &b->source_list); 584 list_add(&use->target_list, &a->target_list); 585 return 0; 586} 587 588/* Module a uses b: caller needs module_mutex() */ 589int ref_module(struct module *a, struct module *b) 590{ 591 int err; 592 593 if (b == NULL || already_uses(a, b)) 594 return 0; 595 596 /* If module isn't available, we fail. */ 597 err = strong_try_module_get(b); 598 if (err) 599 return err; 600 601 err = add_module_usage(a, b); 602 if (err) { 603 module_put(b); 604 return err; 605 } 606 return 0; 607} 608EXPORT_SYMBOL_GPL(ref_module); 609 610/* Clear the unload stuff of the module. */ 611static void module_unload_free(struct module *mod) 612{ 613 struct module_use *use, *tmp; 614 615 mutex_lock(&module_mutex); 616 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { 617 struct module *i = use->target; 618 DEBUGP("%s unusing %s\n", mod->name, i->name); 619 module_put(i); 620 list_del(&use->source_list); 621 list_del(&use->target_list); 622 kfree(use); 623 } 624 mutex_unlock(&module_mutex); 625 626 free_percpu(mod->refptr); 627} 628 629#ifdef CONFIG_MODULE_FORCE_UNLOAD 630static inline int try_force_unload(unsigned int flags) 631{ 632 int ret = (flags & O_TRUNC); 633 if (ret) 634 add_taint(TAINT_FORCED_RMMOD); 635 return ret; 636} 637#else 638static inline int try_force_unload(unsigned int flags) 639{ 640 return 0; 641} 642#endif /* CONFIG_MODULE_FORCE_UNLOAD */ 643 644struct stopref 645{ 646 struct module *mod; 647 int flags; 648 int *forced; 649}; 650 651/* Whole machine is stopped with interrupts off when this runs. */ 652static int __try_stop_module(void *_sref) 653{ 654 struct stopref *sref = _sref; 655 656 /* If it's not unused, quit unless we're forcing. */ 657 if (module_refcount(sref->mod) != 0) { 658 if (!(*sref->forced = try_force_unload(sref->flags))) 659 return -EWOULDBLOCK; 660 } 661 662 /* Mark it as dying. */ 663 sref->mod->state = MODULE_STATE_GOING; 664 return 0; 665} 666 667static int try_stop_module(struct module *mod, int flags, int *forced) 668{ 669 if (flags & O_NONBLOCK) { 670 struct stopref sref = { mod, flags, forced }; 671 672 return stop_machine(__try_stop_module, &sref, NULL); 673 } else { 674 /* We don't need to stop the machine for this. */ 675 mod->state = MODULE_STATE_GOING; 676 synchronize_sched(); 677 return 0; 678 } 679} 680 681unsigned int module_refcount(struct module *mod) 682{ 683 unsigned int incs = 0, decs = 0; 684 int cpu; 685 686 for_each_possible_cpu(cpu) 687 decs += per_cpu_ptr(mod->refptr, cpu)->decs; 688 /* 689 * ensure the incs are added up after the decs. 690 * module_put ensures incs are visible before decs with smp_wmb. 691 * 692 * This 2-count scheme avoids the situation where the refcount 693 * for CPU0 is read, then CPU0 increments the module refcount, 694 * then CPU1 drops that refcount, then the refcount for CPU1 is 695 * read. We would record a decrement but not its corresponding 696 * increment so we would see a low count (disaster). 697 * 698 * Rare situation? But module_refcount can be preempted, and we 699 * might be tallying up 4096+ CPUs. So it is not impossible. 700 */ 701 smp_rmb(); 702 for_each_possible_cpu(cpu) 703 incs += per_cpu_ptr(mod->refptr, cpu)->incs; 704 return incs - decs; 705} 706EXPORT_SYMBOL(module_refcount); 707 708/* This exists whether we can unload or not */ 709static void free_module(struct module *mod); 710 711static void wait_for_zero_refcount(struct module *mod) 712{ 713 /* Since we might sleep for some time, release the mutex first */ 714 mutex_unlock(&module_mutex); 715 for (;;) { 716 DEBUGP("Looking at refcount...\n"); 717 set_current_state(TASK_UNINTERRUPTIBLE); 718 if (module_refcount(mod) == 0) 719 break; 720 schedule(); 721 } 722 current->state = TASK_RUNNING; 723 mutex_lock(&module_mutex); 724} 725 726SYSCALL_DEFINE2(delete_module, const char __user *, name_user, 727 unsigned int, flags) 728{ 729 struct module *mod; 730 char name[MODULE_NAME_LEN]; 731 int ret, forced = 0; 732 733 if (!capable(CAP_SYS_MODULE) || modules_disabled) 734 return -EPERM; 735 736 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) 737 return -EFAULT; 738 name[MODULE_NAME_LEN-1] = '\0'; 739 740 if (mutex_lock_interruptible(&module_mutex) != 0) 741 return -EINTR; 742 743 mod = find_module(name); 744 if (!mod) { 745 ret = -ENOENT; 746 goto out; 747 } 748 749 if (!list_empty(&mod->source_list)) { 750 /* Other modules depend on us: get rid of them first. */ 751 ret = -EWOULDBLOCK; 752 goto out; 753 } 754 755 /* Doing init or already dying? */ 756 if (mod->state != MODULE_STATE_LIVE) { 757 DEBUGP("%s already dying\n", mod->name); 758 ret = -EBUSY; 759 goto out; 760 } 761 762 /* If it has an init func, it must have an exit func to unload */ 763 if (mod->init && !mod->exit) { 764 forced = try_force_unload(flags); 765 if (!forced) { 766 /* This module can't be removed */ 767 ret = -EBUSY; 768 goto out; 769 } 770 } 771 772 /* Set this up before setting mod->state */ 773 mod->waiter = current; 774 775 /* Stop the machine so refcounts can't move and disable module. */ 776 ret = try_stop_module(mod, flags, &forced); 777 if (ret != 0) 778 goto out; 779 780 /* Never wait if forced. */ 781 if (!forced && module_refcount(mod) != 0) 782 wait_for_zero_refcount(mod); 783 784 mutex_unlock(&module_mutex); 785 /* Final destruction now noone is using it. */ 786 if (mod->exit != NULL) 787 mod->exit(); 788 blocking_notifier_call_chain(&module_notify_list, 789 MODULE_STATE_GOING, mod); 790 async_synchronize_full(); 791 792 /* Store the name of the last unloaded module for diagnostic purposes */ 793 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); 794 795 free_module(mod); 796 return 0; 797out: 798 mutex_unlock(&module_mutex); 799 return ret; 800} 801 802static inline void print_unload_info(struct seq_file *m, struct module *mod) 803{ 804 struct module_use *use; 805 int printed_something = 0; 806 807 seq_printf(m, " %u ", module_refcount(mod)); 808 809 /* Always include a trailing , so userspace can differentiate 810 between this and the old multi-field proc format. */ 811 list_for_each_entry(use, &mod->source_list, source_list) { 812 printed_something = 1; 813 seq_printf(m, "%s,", use->source->name); 814 } 815 816 if (mod->init != NULL && mod->exit == NULL) { 817 printed_something = 1; 818 seq_printf(m, "[permanent],"); 819 } 820 821 if (!printed_something) 822 seq_printf(m, "-"); 823} 824 825void __symbol_put(const char *symbol) 826{ 827 struct module *owner; 828 829 preempt_disable(); 830 if (!find_symbol(symbol, &owner, NULL, true, false)) 831 BUG(); 832 module_put(owner); 833 preempt_enable(); 834} 835EXPORT_SYMBOL(__symbol_put); 836 837/* Note this assumes addr is a function, which it currently always is. */ 838void symbol_put_addr(void *addr) 839{ 840 struct module *modaddr; 841 unsigned long a = (unsigned long)dereference_function_descriptor(addr); 842 843 if (core_kernel_text(a)) 844 return; 845 846 /* module_text_address is safe here: we're supposed to have reference 847 * to module from symbol_get, so it can't go away. */ 848 modaddr = __module_text_address(a); 849 BUG_ON(!modaddr); 850 module_put(modaddr); 851} 852EXPORT_SYMBOL_GPL(symbol_put_addr); 853 854static ssize_t show_refcnt(struct module_attribute *mattr, 855 struct module *mod, char *buffer) 856{ 857 return sprintf(buffer, "%u\n", module_refcount(mod)); 858} 859 860static struct module_attribute refcnt = { 861 .attr = { .name = "refcnt", .mode = 0444 }, 862 .show = show_refcnt, 863}; 864 865void module_put(struct module *module) 866{ 867 if (module) { 868 preempt_disable(); 869 smp_wmb(); /* see comment in module_refcount */ 870 __this_cpu_inc(module->refptr->decs); 871 872 trace_module_put(module, _RET_IP_); 873 /* Maybe they're waiting for us to drop reference? */ 874 if (unlikely(!module_is_live(module))) 875 wake_up_process(module->waiter); 876 preempt_enable(); 877 } 878} 879EXPORT_SYMBOL(module_put); 880 881#else /* !CONFIG_MODULE_UNLOAD */ 882static inline void print_unload_info(struct seq_file *m, struct module *mod) 883{ 884 /* We don't know the usage count, or what modules are using. */ 885 seq_printf(m, " - -"); 886} 887 888static inline void module_unload_free(struct module *mod) 889{ 890} 891 892int ref_module(struct module *a, struct module *b) 893{ 894 return strong_try_module_get(b); 895} 896EXPORT_SYMBOL_GPL(ref_module); 897 898static inline int module_unload_init(struct module *mod) 899{ 900 return 0; 901} 902#endif /* CONFIG_MODULE_UNLOAD */ 903 904static ssize_t show_initstate(struct module_attribute *mattr, 905 struct module *mod, char *buffer) 906{ 907 const char *state = "unknown"; 908 909 switch (mod->state) { 910 case MODULE_STATE_LIVE: 911 state = "live"; 912 break; 913 case MODULE_STATE_COMING: 914 state = "coming"; 915 break; 916 case MODULE_STATE_GOING: 917 state = "going"; 918 break; 919 } 920 return sprintf(buffer, "%s\n", state); 921} 922 923static struct module_attribute initstate = { 924 .attr = { .name = "initstate", .mode = 0444 }, 925 .show = show_initstate, 926}; 927 928static struct module_attribute *modinfo_attrs[] = { 929 &modinfo_version, 930 &modinfo_srcversion, 931 &initstate, 932#ifdef CONFIG_MODULE_UNLOAD 933 &refcnt, 934#endif 935 NULL, 936}; 937 938static const char vermagic[] = VERMAGIC_STRING; 939 940static int try_to_force_load(struct module *mod, const char *reason) 941{ 942#ifdef CONFIG_MODULE_FORCE_LOAD 943 if (!test_taint(TAINT_FORCED_MODULE)) 944 printk(KERN_WARNING "%s: %s: kernel tainted.\n", 945 mod->name, reason); 946 add_taint_module(mod, TAINT_FORCED_MODULE); 947 return 0; 948#else 949 return -ENOEXEC; 950#endif 951} 952 953#ifdef CONFIG_MODVERSIONS 954/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ 955static unsigned long maybe_relocated(unsigned long crc, 956 const struct module *crc_owner) 957{ 958#ifdef ARCH_RELOCATES_KCRCTAB 959 if (crc_owner == NULL) 960 return crc - (unsigned long)reloc_start; 961#endif 962 return crc; 963} 964 965static int check_version(Elf_Shdr *sechdrs, 966 unsigned int versindex, 967 const char *symname, 968 struct module *mod, 969 const unsigned long *crc, 970 const struct module *crc_owner) 971{ 972 unsigned int i, num_versions; 973 struct modversion_info *versions; 974 975 /* Exporting module didn't supply crcs? OK, we're already tainted. */ 976 if (!crc) 977 return 1; 978 979 /* No versions at all? modprobe --force does this. */ 980 if (versindex == 0) 981 return try_to_force_load(mod, symname) == 0; 982 983 versions = (void *) sechdrs[versindex].sh_addr; 984 num_versions = sechdrs[versindex].sh_size 985 / sizeof(struct modversion_info); 986 987 for (i = 0; i < num_versions; i++) { 988 if (strcmp(versions[i].name, symname) != 0) 989 continue; 990 991 if (versions[i].crc == maybe_relocated(*crc, crc_owner)) 992 return 1; 993 DEBUGP("Found checksum %lX vs module %lX\n", 994 maybe_relocated(*crc, crc_owner), versions[i].crc); 995 goto bad_version; 996 } 997 998 printk(KERN_WARNING "%s: no symbol version for %s\n", 999 mod->name, symname); 1000 return 0; 1001 1002bad_version: 1003 printk("%s: disagrees about version of symbol %s\n", 1004 mod->name, symname); 1005 return 0; 1006} 1007 1008static inline int check_modstruct_version(Elf_Shdr *sechdrs, 1009 unsigned int versindex, 1010 struct module *mod) 1011{ 1012 const unsigned long *crc; 1013 1014 /* Since this should be found in kernel (which can't be removed), 1015 * no locking is necessary. */ 1016 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL, 1017 &crc, true, false)) 1018 BUG(); 1019 return check_version(sechdrs, versindex, "module_layout", mod, crc, 1020 NULL); 1021} 1022 1023/* First part is kernel version, which we ignore if module has crcs. */ 1024static inline int same_magic(const char *amagic, const char *bmagic, 1025 bool has_crcs) 1026{ 1027 if (has_crcs) { 1028 amagic += strcspn(amagic, " "); 1029 bmagic += strcspn(bmagic, " "); 1030 } 1031 return strcmp(amagic, bmagic) == 0; 1032} 1033#else 1034static inline int check_version(Elf_Shdr *sechdrs, 1035 unsigned int versindex, 1036 const char *symname, 1037 struct module *mod, 1038 const unsigned long *crc, 1039 const struct module *crc_owner) 1040{ 1041 return 1; 1042} 1043 1044static inline int check_modstruct_version(Elf_Shdr *sechdrs, 1045 unsigned int versindex, 1046 struct module *mod) 1047{ 1048 return 1; 1049} 1050 1051static inline int same_magic(const char *amagic, const char *bmagic, 1052 bool has_crcs) 1053{ 1054 return strcmp(amagic, bmagic) == 0; 1055} 1056#endif /* CONFIG_MODVERSIONS */ 1057 1058/* Resolve a symbol for this module. I.e. if we find one, record usage. */ 1059static const struct kernel_symbol *resolve_symbol(struct module *mod, 1060 const struct load_info *info, 1061 const char *name, 1062 char ownername[]) 1063{ 1064 struct module *owner; 1065 const struct kernel_symbol *sym; 1066 const unsigned long *crc; 1067 int err; 1068 1069 mutex_lock(&module_mutex); 1070 sym = find_symbol(name, &owner, &crc, 1071 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); 1072 if (!sym) 1073 goto unlock; 1074 1075 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc, 1076 owner)) { 1077 sym = ERR_PTR(-EINVAL); 1078 goto getname; 1079 } 1080 1081 err = ref_module(mod, owner); 1082 if (err) { 1083 sym = ERR_PTR(err); 1084 goto getname; 1085 } 1086 1087getname: 1088 /* We must make copy under the lock if we failed to get ref. */ 1089 strncpy(ownername, module_name(owner), MODULE_NAME_LEN); 1090unlock: 1091 mutex_unlock(&module_mutex); 1092 return sym; 1093} 1094 1095static const struct kernel_symbol * 1096resolve_symbol_wait(struct module *mod, 1097 const struct load_info *info, 1098 const char *name) 1099{ 1100 const struct kernel_symbol *ksym; 1101 char owner[MODULE_NAME_LEN]; 1102 1103 if (wait_event_interruptible_timeout(module_wq, 1104 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) 1105 || PTR_ERR(ksym) != -EBUSY, 1106 30 * HZ) <= 0) { 1107 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n", 1108 mod->name, owner); 1109 } 1110 return ksym; 1111} 1112 1113/* 1114 * /sys/module/foo/sections stuff 1115 * J. Corbet <corbet@lwn.net> 1116 */ 1117#ifdef CONFIG_SYSFS 1118 1119#ifdef CONFIG_KALLSYMS 1120static inline bool sect_empty(const Elf_Shdr *sect) 1121{ 1122 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; 1123} 1124 1125struct module_sect_attr 1126{ 1127 struct module_attribute mattr; 1128 char *name; 1129 unsigned long address; 1130}; 1131 1132struct module_sect_attrs 1133{ 1134 struct attribute_group grp; 1135 unsigned int nsections; 1136 struct module_sect_attr attrs[0]; 1137}; 1138 1139static ssize_t module_sect_show(struct module_attribute *mattr, 1140 struct module *mod, char *buf) 1141{ 1142 struct module_sect_attr *sattr = 1143 container_of(mattr, struct module_sect_attr, mattr); 1144 return sprintf(buf, "0x%lx\n", sattr->address); 1145} 1146 1147static void free_sect_attrs(struct module_sect_attrs *sect_attrs) 1148{ 1149 unsigned int section; 1150 1151 for (section = 0; section < sect_attrs->nsections; section++) 1152 kfree(sect_attrs->attrs[section].name); 1153 kfree(sect_attrs); 1154} 1155 1156static void add_sect_attrs(struct module *mod, const struct load_info *info) 1157{ 1158 unsigned int nloaded = 0, i, size[2]; 1159 struct module_sect_attrs *sect_attrs; 1160 struct module_sect_attr *sattr; 1161 struct attribute **gattr; 1162 1163 /* Count loaded sections and allocate structures */ 1164 for (i = 0; i < info->hdr->e_shnum; i++) 1165 if (!sect_empty(&info->sechdrs[i])) 1166 nloaded++; 1167 size[0] = ALIGN(sizeof(*sect_attrs) 1168 + nloaded * sizeof(sect_attrs->attrs[0]), 1169 sizeof(sect_attrs->grp.attrs[0])); 1170 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); 1171 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); 1172 if (sect_attrs == NULL) 1173 return; 1174 1175 /* Setup section attributes. */ 1176 sect_attrs->grp.name = "sections"; 1177 sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; 1178 1179 sect_attrs->nsections = 0; 1180 sattr = §_attrs->attrs[0]; 1181 gattr = §_attrs->grp.attrs[0]; 1182 for (i = 0; i < info->hdr->e_shnum; i++) { 1183 Elf_Shdr *sec = &info->sechdrs[i]; 1184 if (sect_empty(sec)) 1185 continue; 1186 sattr->address = sec->sh_addr; 1187 sattr->name = kstrdup(info->secstrings + sec->sh_name, 1188 GFP_KERNEL); 1189 if (sattr->name == NULL) 1190 goto out; 1191 sect_attrs->nsections++; 1192 sysfs_attr_init(&sattr->mattr.attr); 1193 sattr->mattr.show = module_sect_show; 1194 sattr->mattr.store = NULL; 1195 sattr->mattr.attr.name = sattr->name; 1196 sattr->mattr.attr.mode = S_IRUGO; 1197 *(gattr++) = &(sattr++)->mattr.attr; 1198 } 1199 *gattr = NULL; 1200 1201 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) 1202 goto out; 1203 1204 mod->sect_attrs = sect_attrs; 1205 return; 1206 out: 1207 free_sect_attrs(sect_attrs); 1208} 1209 1210static void remove_sect_attrs(struct module *mod) 1211{ 1212 if (mod->sect_attrs) { 1213 sysfs_remove_group(&mod->mkobj.kobj, 1214 &mod->sect_attrs->grp); 1215 /* We are positive that no one is using any sect attrs 1216 * at this point. Deallocate immediately. */ 1217 free_sect_attrs(mod->sect_attrs); 1218 mod->sect_attrs = NULL; 1219 } 1220} 1221 1222/* 1223 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. 1224 */ 1225 1226struct module_notes_attrs { 1227 struct kobject *dir; 1228 unsigned int notes; 1229 struct bin_attribute attrs[0]; 1230}; 1231 1232static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, 1233 struct bin_attribute *bin_attr, 1234 char *buf, loff_t pos, size_t count) 1235{ 1236 /* 1237 * The caller checked the pos and count against our size. 1238 */ 1239 memcpy(buf, bin_attr->private + pos, count); 1240 return count; 1241} 1242 1243static void free_notes_attrs(struct module_notes_attrs *notes_attrs, 1244 unsigned int i) 1245{ 1246 if (notes_attrs->dir) { 1247 while (i-- > 0) 1248 sysfs_remove_bin_file(notes_attrs->dir, 1249 ¬es_attrs->attrs[i]); 1250 kobject_put(notes_attrs->dir); 1251 } 1252 kfree(notes_attrs); 1253} 1254 1255static void add_notes_attrs(struct module *mod, const struct load_info *info) 1256{ 1257 unsigned int notes, loaded, i; 1258 struct module_notes_attrs *notes_attrs; 1259 struct bin_attribute *nattr; 1260 1261 /* failed to create section attributes, so can't create notes */ 1262 if (!mod->sect_attrs) 1263 return; 1264 1265 /* Count notes sections and allocate structures. */ 1266 notes = 0; 1267 for (i = 0; i < info->hdr->e_shnum; i++) 1268 if (!sect_empty(&info->sechdrs[i]) && 1269 (info->sechdrs[i].sh_type == SHT_NOTE)) 1270 ++notes; 1271 1272 if (notes == 0) 1273 return; 1274 1275 notes_attrs = kzalloc(sizeof(*notes_attrs) 1276 + notes * sizeof(notes_attrs->attrs[0]), 1277 GFP_KERNEL); 1278 if (notes_attrs == NULL) 1279 return; 1280 1281 notes_attrs->notes = notes; 1282 nattr = ¬es_attrs->attrs[0]; 1283 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { 1284 if (sect_empty(&info->sechdrs[i])) 1285 continue; 1286 if (info->sechdrs[i].sh_type == SHT_NOTE) { 1287 sysfs_bin_attr_init(nattr); 1288 nattr->attr.name = mod->sect_attrs->attrs[loaded].name; 1289 nattr->attr.mode = S_IRUGO; 1290 nattr->size = info->sechdrs[i].sh_size; 1291 nattr->private = (void *) info->sechdrs[i].sh_addr; 1292 nattr->read = module_notes_read; 1293 ++nattr; 1294 } 1295 ++loaded; 1296 } 1297 1298 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); 1299 if (!notes_attrs->dir) 1300 goto out; 1301 1302 for (i = 0; i < notes; ++i) 1303 if (sysfs_create_bin_file(notes_attrs->dir, 1304 ¬es_attrs->attrs[i])) 1305 goto out; 1306 1307 mod->notes_attrs = notes_attrs; 1308 return; 1309 1310 out: 1311 free_notes_attrs(notes_attrs, i); 1312} 1313 1314static void remove_notes_attrs(struct module *mod) 1315{ 1316 if (mod->notes_attrs) 1317 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); 1318} 1319 1320#else 1321 1322static inline void add_sect_attrs(struct module *mod, 1323 const struct load_info *info) 1324{ 1325} 1326 1327static inline void remove_sect_attrs(struct module *mod) 1328{ 1329} 1330 1331static inline void add_notes_attrs(struct module *mod, 1332 const struct load_info *info) 1333{ 1334} 1335 1336static inline void remove_notes_attrs(struct module *mod) 1337{ 1338} 1339#endif /* CONFIG_KALLSYMS */ 1340 1341static void add_usage_links(struct module *mod) 1342{ 1343#ifdef CONFIG_MODULE_UNLOAD 1344 struct module_use *use; 1345 int nowarn; 1346 1347 mutex_lock(&module_mutex); 1348 list_for_each_entry(use, &mod->target_list, target_list) { 1349 nowarn = sysfs_create_link(use->target->holders_dir, 1350 &mod->mkobj.kobj, mod->name); 1351 } 1352 mutex_unlock(&module_mutex); 1353#endif 1354} 1355 1356static void del_usage_links(struct module *mod) 1357{ 1358#ifdef CONFIG_MODULE_UNLOAD 1359 struct module_use *use; 1360 1361 mutex_lock(&module_mutex); 1362 list_for_each_entry(use, &mod->target_list, target_list) 1363 sysfs_remove_link(use->target->holders_dir, mod->name); 1364 mutex_unlock(&module_mutex); 1365#endif 1366} 1367 1368static int module_add_modinfo_attrs(struct module *mod) 1369{ 1370 struct module_attribute *attr; 1371 struct module_attribute *temp_attr; 1372 int error = 0; 1373 int i; 1374 1375 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * 1376 (ARRAY_SIZE(modinfo_attrs) + 1)), 1377 GFP_KERNEL); 1378 if (!mod->modinfo_attrs) 1379 return -ENOMEM; 1380 1381 temp_attr = mod->modinfo_attrs; 1382 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { 1383 if (!attr->test || 1384 (attr->test && attr->test(mod))) { 1385 memcpy(temp_attr, attr, sizeof(*temp_attr)); 1386 sysfs_attr_init(&temp_attr->attr); 1387 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); 1388 ++temp_attr; 1389 } 1390 } 1391 return error; 1392} 1393 1394static void module_remove_modinfo_attrs(struct module *mod) 1395{ 1396 struct module_attribute *attr; 1397 int i; 1398 1399 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { 1400 /* pick a field to test for end of list */ 1401 if (!attr->attr.name) 1402 break; 1403 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); 1404 if (attr->free) 1405 attr->free(mod); 1406 } 1407 kfree(mod->modinfo_attrs); 1408} 1409 1410static int mod_sysfs_init(struct module *mod) 1411{ 1412 int err; 1413 struct kobject *kobj; 1414 1415 if (!module_sysfs_initialized) { 1416 printk(KERN_ERR "%s: module sysfs not initialized\n", 1417 mod->name); 1418 err = -EINVAL; 1419 goto out; 1420 } 1421 1422 kobj = kset_find_obj(module_kset, mod->name); 1423 if (kobj) { 1424 printk(KERN_ERR "%s: module is already loaded\n", mod->name); 1425 kobject_put(kobj); 1426 err = -EINVAL; 1427 goto out; 1428 } 1429 1430 mod->mkobj.mod = mod; 1431 1432 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); 1433 mod->mkobj.kobj.kset = module_kset; 1434 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, 1435 "%s", mod->name); 1436 if (err) 1437 kobject_put(&mod->mkobj.kobj); 1438 1439 /* delay uevent until full sysfs population */ 1440out: 1441 return err; 1442} 1443 1444static int mod_sysfs_setup(struct module *mod, 1445 const struct load_info *info, 1446 struct kernel_param *kparam, 1447 unsigned int num_params) 1448{ 1449 int err; 1450 1451 err = mod_sysfs_init(mod); 1452 if (err) 1453 goto out; 1454 1455 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); 1456 if (!mod->holders_dir) { 1457 err = -ENOMEM; 1458 goto out_unreg; 1459 } 1460 1461 err = module_param_sysfs_setup(mod, kparam, num_params); 1462 if (err) 1463 goto out_unreg_holders; 1464 1465 err = module_add_modinfo_attrs(mod); 1466 if (err) 1467 goto out_unreg_param; 1468 1469 add_usage_links(mod); 1470 add_sect_attrs(mod, info); 1471 add_notes_attrs(mod, info); 1472 1473 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); 1474 return 0; 1475 1476out_unreg_param: 1477 module_param_sysfs_remove(mod); 1478out_unreg_holders: 1479 kobject_put(mod->holders_dir); 1480out_unreg: 1481 kobject_put(&mod->mkobj.kobj); 1482out: 1483 return err; 1484} 1485 1486static void mod_sysfs_fini(struct module *mod) 1487{ 1488 remove_notes_attrs(mod); 1489 remove_sect_attrs(mod); 1490 kobject_put(&mod->mkobj.kobj); 1491} 1492 1493#else /* !CONFIG_SYSFS */ 1494 1495static int mod_sysfs_setup(struct module *mod, 1496 const struct load_info *info, 1497 struct kernel_param *kparam, 1498 unsigned int num_params) 1499{ 1500 return 0; 1501} 1502 1503static void mod_sysfs_fini(struct module *mod) 1504{ 1505} 1506 1507static void module_remove_modinfo_attrs(struct module *mod) 1508{ 1509} 1510 1511static void del_usage_links(struct module *mod) 1512{ 1513} 1514 1515#endif /* CONFIG_SYSFS */ 1516 1517static void mod_sysfs_teardown(struct module *mod) 1518{ 1519 del_usage_links(mod); 1520 module_remove_modinfo_attrs(mod); 1521 module_param_sysfs_remove(mod); 1522 kobject_put(mod->mkobj.drivers_dir); 1523 kobject_put(mod->holders_dir); 1524 mod_sysfs_fini(mod); 1525} 1526 1527/* 1528 * unlink the module with the whole machine is stopped with interrupts off 1529 * - this defends against kallsyms not taking locks 1530 */ 1531static int __unlink_module(void *_mod) 1532{ 1533 struct module *mod = _mod; 1534 list_del(&mod->list); 1535 module_bug_cleanup(mod); 1536 return 0; 1537} 1538 1539/* Free a module, remove from lists, etc. */ 1540static void free_module(struct module *mod) 1541{ 1542 trace_module_free(mod); 1543 1544 /* Delete from various lists */ 1545 mutex_lock(&module_mutex); 1546 stop_machine(__unlink_module, mod, NULL); 1547 mutex_unlock(&module_mutex); 1548 mod_sysfs_teardown(mod); 1549 1550 /* Remove dynamic debug info */ 1551 ddebug_remove_module(mod->name); 1552 1553 /* Arch-specific cleanup. */ 1554 module_arch_cleanup(mod); 1555 1556 /* Module unload stuff */ 1557 module_unload_free(mod); 1558 1559 /* Free any allocated parameters. */ 1560 destroy_params(mod->kp, mod->num_kp); 1561 1562 /* This may be NULL, but that's OK */ 1563 module_free(mod, mod->module_init); 1564 kfree(mod->args); 1565 percpu_modfree(mod); 1566 1567 /* Free lock-classes: */ 1568 lockdep_free_key_range(mod->module_core, mod->core_size); 1569 1570 /* Finally, free the core (containing the module structure) */ 1571 module_free(mod, mod->module_core); 1572 1573#ifdef CONFIG_MPU 1574 update_protections(current->mm); 1575#endif 1576} 1577 1578void *__symbol_get(const char *symbol) 1579{ 1580 struct module *owner; 1581 const struct kernel_symbol *sym; 1582 1583 preempt_disable(); 1584 sym = find_symbol(symbol, &owner, NULL, true, true); 1585 if (sym && strong_try_module_get(owner)) 1586 sym = NULL; 1587 preempt_enable(); 1588 1589 return sym ? (void *)sym->value : NULL; 1590} 1591EXPORT_SYMBOL_GPL(__symbol_get); 1592 1593/* 1594 * Ensure that an exported symbol [global namespace] does not already exist 1595 * in the kernel or in some other module's exported symbol table. 1596 * 1597 * You must hold the module_mutex. 1598 */ 1599static int verify_export_symbols(struct module *mod) 1600{ 1601 unsigned int i; 1602 struct module *owner; 1603 const struct kernel_symbol *s; 1604 struct { 1605 const struct kernel_symbol *sym; 1606 unsigned int num; 1607 } arr[] = { 1608 { mod->syms, mod->num_syms }, 1609 { mod->gpl_syms, mod->num_gpl_syms }, 1610 { mod->gpl_future_syms, mod->num_gpl_future_syms }, 1611#ifdef CONFIG_UNUSED_SYMBOLS 1612 { mod->unused_syms, mod->num_unused_syms }, 1613 { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, 1614#endif 1615 }; 1616 1617 for (i = 0; i < ARRAY_SIZE(arr); i++) { 1618 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { 1619 if (find_symbol(s->name, &owner, NULL, true, false)) { 1620 printk(KERN_ERR 1621 "%s: exports duplicate symbol %s" 1622 " (owned by %s)\n", 1623 mod->name, s->name, module_name(owner)); 1624 return -ENOEXEC; 1625 } 1626 } 1627 } 1628 return 0; 1629} 1630 1631/* Change all symbols so that st_value encodes the pointer directly. */ 1632static int simplify_symbols(struct module *mod, const struct load_info *info) 1633{ 1634 Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; 1635 Elf_Sym *sym = (void *)symsec->sh_addr; 1636 unsigned long secbase; 1637 unsigned int i; 1638 int ret = 0; 1639 const struct kernel_symbol *ksym; 1640 1641 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { 1642 const char *name = info->strtab + sym[i].st_name; 1643 1644 switch (sym[i].st_shndx) { 1645 case SHN_COMMON: 1646 /* We compiled with -fno-common. These are not 1647 supposed to happen. */ 1648 DEBUGP("Common symbol: %s\n", name); 1649 printk("%s: please compile with -fno-common\n", 1650 mod->name); 1651 ret = -ENOEXEC; 1652 break; 1653 1654 case SHN_ABS: 1655 /* Don't need to do anything */ 1656 DEBUGP("Absolute symbol: 0x%08lx\n", 1657 (long)sym[i].st_value); 1658 break; 1659 1660 case SHN_UNDEF: 1661 ksym = resolve_symbol_wait(mod, info, name); 1662 /* Ok if resolved. */ 1663 if (ksym && !IS_ERR(ksym)) { 1664 sym[i].st_value = ksym->value; 1665 break; 1666 } 1667 1668 /* Ok if weak. */ 1669 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK) 1670 break; 1671 1672 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n", 1673 mod->name, name, PTR_ERR(ksym)); 1674 ret = PTR_ERR(ksym) ?: -ENOENT; 1675 break; 1676 1677 default: 1678 /* Divert to percpu allocation if a percpu var. */ 1679 if (sym[i].st_shndx == info->index.pcpu) 1680 secbase = (unsigned long)mod_percpu(mod); 1681 else 1682 secbase = info->sechdrs[sym[i].st_shndx].sh_addr; 1683 sym[i].st_value += secbase; 1684 break; 1685 } 1686 } 1687 1688 return ret; 1689} 1690 1691static int apply_relocations(struct module *mod, const struct load_info *info) 1692{ 1693 unsigned int i; 1694 int err = 0; 1695 1696 /* Now do relocations. */ 1697 for (i = 1; i < info->hdr->e_shnum; i++) { 1698 unsigned int infosec = info->sechdrs[i].sh_info; 1699 1700 /* Not a valid relocation section? */ 1701 if (infosec >= info->hdr->e_shnum) 1702 continue; 1703 1704 /* Don't bother with non-allocated sections */ 1705 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) 1706 continue; 1707 1708 if (info->sechdrs[i].sh_type == SHT_REL) 1709 err = apply_relocate(info->sechdrs, info->strtab, 1710 info->index.sym, i, mod); 1711 else if (info->sechdrs[i].sh_type == SHT_RELA) 1712 err = apply_relocate_add(info->sechdrs, info->strtab, 1713 info->index.sym, i, mod); 1714 if (err < 0) 1715 break; 1716 } 1717 return err; 1718} 1719 1720/* Additional bytes needed by arch in front of individual sections */ 1721unsigned int __weak arch_mod_section_prepend(struct module *mod, 1722 unsigned int section) 1723{ 1724 /* default implementation just returns zero */ 1725 return 0; 1726} 1727 1728/* Update size with this section: return offset. */ 1729static long get_offset(struct module *mod, unsigned int *size, 1730 Elf_Shdr *sechdr, unsigned int section) 1731{ 1732 long ret; 1733 1734 *size += arch_mod_section_prepend(mod, section); 1735 ret = ALIGN(*size, sechdr->sh_addralign ?: 1); 1736 *size = ret + sechdr->sh_size; 1737 return ret; 1738} 1739 1740/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld 1741 might -- code, read-only data, read-write data, small data. Tally 1742 sizes, and place the offsets into sh_entsize fields: high bit means it 1743 belongs in init. */ 1744static void layout_sections(struct module *mod, struct load_info *info) 1745{ 1746 static unsigned long const masks[][2] = { 1747 /* NOTE: all executable code must be the first section 1748 * in this array; otherwise modify the text_size 1749 * finder in the two loops below */ 1750 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, 1751 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, 1752 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, 1753 { ARCH_SHF_SMALL | SHF_ALLOC, 0 } 1754 }; 1755 unsigned int m, i; 1756 1757 for (i = 0; i < info->hdr->e_shnum; i++) 1758 info->sechdrs[i].sh_entsize = ~0UL; 1759 1760 DEBUGP("Core section allocation order:\n"); 1761 for (m = 0; m < ARRAY_SIZE(masks); ++m) { 1762 for (i = 0; i < info->hdr->e_shnum; ++i) { 1763 Elf_Shdr *s = &info->sechdrs[i]; 1764 const char *sname = info->secstrings + s->sh_name; 1765 1766 if ((s->sh_flags & masks[m][0]) != masks[m][0] 1767 || (s->sh_flags & masks[m][1]) 1768 || s->sh_entsize != ~0UL 1769 || strstarts(sname, ".init")) 1770 continue; 1771 s->sh_entsize = get_offset(mod, &mod->core_size, s, i); 1772 DEBUGP("\t%s\n", name); 1773 } 1774 if (m == 0) 1775 mod->core_text_size = mod->core_size; 1776 } 1777 1778 DEBUGP("Init section allocation order:\n"); 1779 for (m = 0; m < ARRAY_SIZE(masks); ++m) { 1780 for (i = 0; i < info->hdr->e_shnum; ++i) { 1781 Elf_Shdr *s = &info->sechdrs[i]; 1782 const char *sname = info->secstrings + s->sh_name; 1783 1784 if ((s->sh_flags & masks[m][0]) != masks[m][0] 1785 || (s->sh_flags & masks[m][1]) 1786 || s->sh_entsize != ~0UL 1787 || !strstarts(sname, ".init")) 1788 continue; 1789 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i) 1790 | INIT_OFFSET_MASK); 1791 DEBUGP("\t%s\n", sname); 1792 } 1793 if (m == 0) 1794 mod->init_text_size = mod->init_size; 1795 } 1796} 1797 1798static void set_license(struct module *mod, const char *license) 1799{ 1800 if (!license) 1801 license = "unspecified"; 1802 1803#ifndef CONFIG_LOCKDEP 1804 if (!license_is_gpl_compatible(license)) { 1805 if (!test_taint(TAINT_PROPRIETARY_MODULE)) 1806 printk(KERN_WARNING "%s: module license '%s' taints " 1807 "kernel.\n", mod->name, license); 1808 add_taint_module(mod, TAINT_PROPRIETARY_MODULE); 1809 } 1810#endif 1811} 1812 1813/* Parse tag=value strings from .modinfo section */ 1814static char *next_string(char *string, unsigned long *secsize) 1815{ 1816 /* Skip non-zero chars */ 1817 while (string[0]) { 1818 string++; 1819 if ((*secsize)-- <= 1) 1820 return NULL; 1821 } 1822 1823 /* Skip any zero padding. */ 1824 while (!string[0]) { 1825 string++; 1826 if ((*secsize)-- <= 1) 1827 return NULL; 1828 } 1829 return string; 1830} 1831 1832static char *get_modinfo(struct load_info *info, const char *tag) 1833{ 1834 char *p; 1835 unsigned int taglen = strlen(tag); 1836 Elf_Shdr *infosec = &info->sechdrs[info->index.info]; 1837 unsigned long size = infosec->sh_size; 1838 1839 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) { 1840 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 1841 return p + taglen + 1; 1842 } 1843 return NULL; 1844} 1845 1846static void setup_modinfo(struct module *mod, struct load_info *info) 1847{ 1848 struct module_attribute *attr; 1849 int i; 1850 1851 for (i = 0; (attr = modinfo_attrs[i]); i++) { 1852 if (attr->setup) 1853 attr->setup(mod, get_modinfo(info, attr->attr.name)); 1854 } 1855} 1856 1857static void free_modinfo(struct module *mod) 1858{ 1859 struct module_attribute *attr; 1860 int i; 1861 1862 for (i = 0; (attr = modinfo_attrs[i]); i++) { 1863 if (attr->free) 1864 attr->free(mod); 1865 } 1866} 1867 1868#ifdef CONFIG_KALLSYMS 1869 1870/* lookup symbol in given range of kernel_symbols */ 1871static const struct kernel_symbol *lookup_symbol(const char *name, 1872 const struct kernel_symbol *start, 1873 const struct kernel_symbol *stop) 1874{ 1875 const struct kernel_symbol *ks = start; 1876 for (; ks < stop; ks++) 1877 if (strcmp(ks->name, name) == 0) 1878 return ks; 1879 return NULL; 1880} 1881 1882static int is_exported(const char *name, unsigned long value, 1883 const struct module *mod) 1884{ 1885 const struct kernel_symbol *ks; 1886 if (!mod) 1887 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); 1888 else 1889 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); 1890 return ks != NULL && ks->value == value; 1891} 1892 1893/* As per nm */ 1894static char elf_type(const Elf_Sym *sym, const struct load_info *info) 1895{ 1896 const Elf_Shdr *sechdrs = info->sechdrs; 1897 1898 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { 1899 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) 1900 return 'v'; 1901 else 1902 return 'w'; 1903 } 1904 if (sym->st_shndx == SHN_UNDEF) 1905 return 'U'; 1906 if (sym->st_shndx == SHN_ABS) 1907 return 'a'; 1908 if (sym->st_shndx >= SHN_LORESERVE) 1909 return '?'; 1910 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) 1911 return 't'; 1912 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC 1913 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { 1914 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) 1915 return 'r'; 1916 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) 1917 return 'g'; 1918 else 1919 return 'd'; 1920 } 1921 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { 1922 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) 1923 return 's'; 1924 else 1925 return 'b'; 1926 } 1927 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, 1928 ".debug")) { 1929 return 'n'; 1930 } 1931 return '?'; 1932} 1933 1934static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, 1935 unsigned int shnum) 1936{ 1937 const Elf_Shdr *sec; 1938 1939 if (src->st_shndx == SHN_UNDEF 1940 || src->st_shndx >= shnum 1941 || !src->st_name) 1942 return false; 1943 1944 sec = sechdrs + src->st_shndx; 1945 if (!(sec->sh_flags & SHF_ALLOC) 1946#ifndef CONFIG_KALLSYMS_ALL 1947 || !(sec->sh_flags & SHF_EXECINSTR) 1948#endif 1949 || (sec->sh_entsize & INIT_OFFSET_MASK)) 1950 return false; 1951 1952 return true; 1953} 1954 1955static void layout_symtab(struct module *mod, struct load_info *info) 1956{ 1957 Elf_Shdr *symsect = info->sechdrs + info->index.sym; 1958 Elf_Shdr *strsect = info->sechdrs + info->index.str; 1959 const Elf_Sym *src; 1960 unsigned int i, nsrc, ndst; 1961 1962 /* Put symbol section at end of init part of module. */ 1963 symsect->sh_flags |= SHF_ALLOC; 1964 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect, 1965 info->index.sym) | INIT_OFFSET_MASK; 1966 DEBUGP("\t%s\n", info->secstrings + symsect->sh_name); 1967 1968 src = (void *)info->hdr + symsect->sh_offset; 1969 nsrc = symsect->sh_size / sizeof(*src); 1970 for (ndst = i = 1; i < nsrc; ++i, ++src) 1971 if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) { 1972 unsigned int j = src->st_name; 1973 1974 while (!__test_and_set_bit(j, info->strmap) 1975 && info->strtab[j]) 1976 ++j; 1977 ++ndst; 1978 } 1979 1980 /* Append room for core symbols at end of core part. */ 1981 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1); 1982 mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym); 1983 1984 /* Put string table section at end of init part of module. */ 1985 strsect->sh_flags |= SHF_ALLOC; 1986 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect, 1987 info->index.str) | INIT_OFFSET_MASK; 1988 DEBUGP("\t%s\n", info->secstrings + strsect->sh_name); 1989 1990 /* Append room for core symbols' strings at end of core part. */ 1991 info->stroffs = mod->core_size; 1992 __set_bit(0, info->strmap); 1993 mod->core_size += bitmap_weight(info->strmap, strsect->sh_size); 1994} 1995 1996static void add_kallsyms(struct module *mod, const struct load_info *info) 1997{ 1998 unsigned int i, ndst; 1999 const Elf_Sym *src; 2000 Elf_Sym *dst; 2001 char *s; 2002 Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; 2003 2004 mod->symtab = (void *)symsec->sh_addr; 2005 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym); 2006 /* Make sure we get permanent strtab: don't use info->strtab. */ 2007 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr; 2008 2009 /* Set types up while we still have access to sections. */ 2010 for (i = 0; i < mod->num_symtab; i++) 2011 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info); 2012 2013 mod->core_symtab = dst = mod->module_core + info->symoffs; 2014 src = mod->symtab; 2015 *dst = *src; 2016 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) { 2017 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) 2018 continue; 2019 dst[ndst] = *src; 2020 dst[ndst].st_name = bitmap_weight(info->strmap, 2021 dst[ndst].st_name); 2022 ++ndst; 2023 } 2024 mod->core_num_syms = ndst; 2025 2026 mod->core_strtab = s = mod->module_core + info->stroffs; 2027 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i) 2028 if (test_bit(i, info->strmap)) 2029 *++s = mod->strtab[i]; 2030} 2031#else 2032static inline void layout_symtab(struct module *mod, struct load_info *info) 2033{ 2034} 2035 2036static void add_kallsyms(struct module *mod, struct load_info *info) 2037{ 2038} 2039#endif /* CONFIG_KALLSYMS */ 2040 2041static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num) 2042{ 2043 if (!debug) 2044 return; 2045#ifdef CONFIG_DYNAMIC_DEBUG 2046 if (ddebug_add_module(debug, num, debug->modname)) 2047 printk(KERN_ERR "dynamic debug error adding module: %s\n", 2048 debug->modname); 2049#endif 2050} 2051 2052static void dynamic_debug_remove(struct _ddebug *debug) 2053{ 2054 if (debug) 2055 ddebug_remove_module(debug->modname); 2056} 2057 2058static void *module_alloc_update_bounds(unsigned long size) 2059{ 2060 void *ret = module_alloc(size); 2061 2062 if (ret) { 2063 mutex_lock(&module_mutex); 2064 /* Update module bounds. */ 2065 if ((unsigned long)ret < module_addr_min) 2066 module_addr_min = (unsigned long)ret; 2067 if ((unsigned long)ret + size > module_addr_max) 2068 module_addr_max = (unsigned long)ret + size; 2069 mutex_unlock(&module_mutex); 2070 } 2071 return ret; 2072} 2073 2074#ifdef CONFIG_DEBUG_KMEMLEAK 2075static void kmemleak_load_module(const struct module *mod, 2076 const struct load_info *info) 2077{ 2078 unsigned int i; 2079 2080 /* only scan the sections containing data */ 2081 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); 2082 2083 for (i = 1; i < info->hdr->e_shnum; i++) { 2084 const char *name = info->secstrings + info->sechdrs[i].sh_name; 2085 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC)) 2086 continue; 2087 if (!strstarts(name, ".data") && !strstarts(name, ".bss")) 2088 continue; 2089 2090 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, 2091 info->sechdrs[i].sh_size, GFP_KERNEL); 2092 } 2093} 2094#else 2095static inline void kmemleak_load_module(const struct module *mod, 2096 const struct load_info *info) 2097{ 2098} 2099#endif 2100 2101/* Sets info->hdr and info->len. */ 2102static int copy_and_check(struct load_info *info, 2103 const void __user *umod, unsigned long len, 2104 const char __user *uargs) 2105{ 2106 int err; 2107 Elf_Ehdr *hdr; 2108 2109 if (len < sizeof(*hdr)) 2110 return -ENOEXEC; 2111 2112 /* Suck in entire file: we'll want most of it. */ 2113 /* vmalloc barfs on "unusual" numbers. Check here */ 2114 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL) 2115 return -ENOMEM; 2116 2117 if (copy_from_user(hdr, umod, len) != 0) { 2118 err = -EFAULT; 2119 goto free_hdr; 2120 } 2121 2122 /* Sanity checks against insmoding binaries or wrong arch, 2123 weird elf version */ 2124 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 2125 || hdr->e_type != ET_REL 2126 || !elf_check_arch(hdr) 2127 || hdr->e_shentsize != sizeof(Elf_Shdr)) { 2128 err = -ENOEXEC; 2129 goto free_hdr; 2130 } 2131 2132 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) { 2133 err = -ENOEXEC; 2134 goto free_hdr; 2135 } 2136 2137 info->hdr = hdr; 2138 info->len = len; 2139 return 0; 2140 2141free_hdr: 2142 vfree(hdr); 2143 return err; 2144} 2145 2146static void free_copy(struct load_info *info) 2147{ 2148 vfree(info->hdr); 2149} 2150 2151static int rewrite_section_headers(struct load_info *info) 2152{ 2153 unsigned int i; 2154 2155 /* This should always be true, but let's be sure. */ 2156 info->sechdrs[0].sh_addr = 0; 2157 2158 for (i = 1; i < info->hdr->e_shnum; i++) { 2159 Elf_Shdr *shdr = &info->sechdrs[i]; 2160 if (shdr->sh_type != SHT_NOBITS 2161 && info->len < shdr->sh_offset + shdr->sh_size) { 2162 printk(KERN_ERR "Module len %lu truncated\n", 2163 info->len); 2164 return -ENOEXEC; 2165 } 2166 2167 /* Mark all sections sh_addr with their address in the 2168 temporary image. */ 2169 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; 2170 2171#ifndef CONFIG_MODULE_UNLOAD 2172 /* Don't load .exit sections */ 2173 if (strstarts(info->secstrings+shdr->sh_name, ".exit")) 2174 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; 2175#endif 2176 } 2177 2178 /* Track but don't keep modinfo and version sections. */ 2179 info->index.vers = find_sec(info, "__versions"); 2180 info->index.info = find_sec(info, ".modinfo"); 2181 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; 2182 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; 2183 return 0; 2184} 2185 2186/* 2187 * Set up our basic convenience variables (pointers to section headers, 2188 * search for module section index etc), and do some basic section 2189 * verification. 2190 * 2191 * Return the temporary module pointer (we'll replace it with the final 2192 * one when we move the module sections around). 2193 */ 2194static struct module *setup_load_info(struct load_info *info) 2195{ 2196 unsigned int i; 2197 int err; 2198 struct module *mod; 2199 2200 /* Set up the convenience variables */ 2201 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; 2202 info->secstrings = (void *)info->hdr 2203 + info->sechdrs[info->hdr->e_shstrndx].sh_offset; 2204 2205 err = rewrite_section_headers(info); 2206 if (err) 2207 return ERR_PTR(err); 2208 2209 /* Find internal symbols and strings. */ 2210 for (i = 1; i < info->hdr->e_shnum; i++) { 2211 if (info->sechdrs[i].sh_type == SHT_SYMTAB) { 2212 info->index.sym = i; 2213 info->index.str = info->sechdrs[i].sh_link; 2214 info->strtab = (char *)info->hdr 2215 + info->sechdrs[info->index.str].sh_offset; 2216 break; 2217 } 2218 } 2219 2220 info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); 2221 if (!info->index.mod) { 2222 printk(KERN_WARNING "No module found in object\n"); 2223 return ERR_PTR(-ENOEXEC); 2224 } 2225 /* This is temporary: point mod into copy of data. */ 2226 mod = (void *)info->sechdrs[info->index.mod].sh_addr; 2227 2228 if (info->index.sym == 0) { 2229 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n", 2230 mod->name); 2231 return ERR_PTR(-ENOEXEC); 2232 } 2233 2234 info->index.pcpu = find_pcpusec(info); 2235 2236 /* Check module struct version now, before we try to use module. */ 2237 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod)) 2238 return ERR_PTR(-ENOEXEC); 2239 2240 return mod; 2241} 2242 2243static int check_modinfo(struct module *mod, struct load_info *info) 2244{ 2245 const char *modmagic = get_modinfo(info, "vermagic"); 2246 int err; 2247 2248 /* This is allowed: modprobe --force will invalidate it. */ 2249 if (!modmagic) { 2250 err = try_to_force_load(mod, "bad vermagic"); 2251 if (err) 2252 return err; 2253 } else if (!same_magic(modmagic, vermagic, info->index.vers)) { 2254 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", 2255 mod->name, modmagic, vermagic); 2256 return -ENOEXEC; 2257 } 2258 2259 if (get_modinfo(info, "staging")) { 2260 add_taint_module(mod, TAINT_CRAP); 2261 printk(KERN_WARNING "%s: module is from the staging directory," 2262 " the quality is unknown, you have been warned.\n", 2263 mod->name); 2264 } 2265 2266 /* Set up license info based on the info section */ 2267 set_license(mod, get_modinfo(info, "license")); 2268 2269 return 0; 2270} 2271 2272static void find_module_sections(struct module *mod, struct load_info *info) 2273{ 2274 mod->kp = section_objs(info, "__param", 2275 sizeof(*mod->kp), &mod->num_kp); 2276 mod->syms = section_objs(info, "__ksymtab", 2277 sizeof(*mod->syms), &mod->num_syms); 2278 mod->crcs = section_addr(info, "__kcrctab"); 2279 mod->gpl_syms = section_objs(info, "__ksymtab_gpl", 2280 sizeof(*mod->gpl_syms), 2281 &mod->num_gpl_syms); 2282 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); 2283 mod->gpl_future_syms = section_objs(info, 2284 "__ksymtab_gpl_future", 2285 sizeof(*mod->gpl_future_syms), 2286 &mod->num_gpl_future_syms); 2287 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); 2288 2289#ifdef CONFIG_UNUSED_SYMBOLS 2290 mod->unused_syms = section_objs(info, "__ksymtab_unused", 2291 sizeof(*mod->unused_syms), 2292 &mod->num_unused_syms); 2293 mod->unused_crcs = section_addr(info, "__kcrctab_unused"); 2294 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", 2295 sizeof(*mod->unused_gpl_syms), 2296 &mod->num_unused_gpl_syms); 2297 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); 2298#endif 2299#ifdef CONFIG_CONSTRUCTORS 2300 mod->ctors = section_objs(info, ".ctors", 2301 sizeof(*mod->ctors), &mod->num_ctors); 2302#endif 2303 2304#ifdef CONFIG_TRACEPOINTS 2305 mod->tracepoints = section_objs(info, "__tracepoints", 2306 sizeof(*mod->tracepoints), 2307 &mod->num_tracepoints); 2308#endif 2309#ifdef CONFIG_EVENT_TRACING 2310 mod->trace_events = section_objs(info, "_ftrace_events", 2311 sizeof(*mod->trace_events), 2312 &mod->num_trace_events); 2313 /* 2314 * This section contains pointers to allocated objects in the trace 2315 * code and not scanning it leads to false positives. 2316 */ 2317 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) * 2318 mod->num_trace_events, GFP_KERNEL); 2319#endif 2320#ifdef CONFIG_FTRACE_MCOUNT_RECORD 2321 /* sechdrs[0].sh_size is always zero */ 2322 mod->ftrace_callsites = section_objs(info, "__mcount_loc", 2323 sizeof(*mod->ftrace_callsites), 2324 &mod->num_ftrace_callsites); 2325#endif 2326 2327 mod->extable = section_objs(info, "__ex_table", 2328 sizeof(*mod->extable), &mod->num_exentries); 2329 2330 if (section_addr(info, "__obsparm")) 2331 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", 2332 mod->name); 2333 2334 info->debug = section_objs(info, "__verbose", 2335 sizeof(*info->debug), &info->num_debug); 2336} 2337 2338static int move_module(struct module *mod, struct load_info *info) 2339{ 2340 int i; 2341 void *ptr; 2342 2343 /* Do the allocs. */ 2344 ptr = module_alloc_update_bounds(mod->core_size); 2345 /* 2346 * The pointer to this block is stored in the module structure 2347 * which is inside the block. Just mark it as not being a 2348 * leak. 2349 */ 2350 kmemleak_not_leak(ptr); 2351 if (!ptr) 2352 return -ENOMEM; 2353 2354 memset(ptr, 0, mod->core_size); 2355 mod->module_core = ptr; 2356 2357 ptr = module_alloc_update_bounds(mod->init_size); 2358 /* 2359 * The pointer to this block is stored in the module structure 2360 * which is inside the block. This block doesn't need to be 2361 * scanned as it contains data and code that will be freed 2362 * after the module is initialized. 2363 */ 2364 kmemleak_ignore(ptr); 2365 if (!ptr && mod->init_size) { 2366 module_free(mod, mod->module_core); 2367 return -ENOMEM; 2368 } 2369 memset(ptr, 0, mod->init_size); 2370 mod->module_init = ptr; 2371 2372 /* Transfer each section which specifies SHF_ALLOC */ 2373 DEBUGP("final section addresses:\n"); 2374 for (i = 0; i < info->hdr->e_shnum; i++) { 2375 void *dest; 2376 Elf_Shdr *shdr = &info->sechdrs[i]; 2377 2378 if (!(shdr->sh_flags & SHF_ALLOC)) 2379 continue; 2380 2381 if (shdr->sh_entsize & INIT_OFFSET_MASK) 2382 dest = mod->module_init 2383 + (shdr->sh_entsize & ~INIT_OFFSET_MASK); 2384 else 2385 dest = mod->module_core + shdr->sh_entsize; 2386 2387 if (shdr->sh_type != SHT_NOBITS) 2388 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); 2389 /* Update sh_addr to point to copy in image. */ 2390 shdr->sh_addr = (unsigned long)dest; 2391 DEBUGP("\t0x%lx %s\n", 2392 shdr->sh_addr, info->secstrings + shdr->sh_name); 2393 } 2394 2395 return 0; 2396} 2397 2398static int check_module_license_and_versions(struct module *mod) 2399{ 2400 /* 2401 * ndiswrapper is under GPL by itself, but loads proprietary modules. 2402 * Don't use add_taint_module(), as it would prevent ndiswrapper from 2403 * using GPL-only symbols it needs. 2404 */ 2405 if (strcmp(mod->name, "ndiswrapper") == 0) 2406 add_taint(TAINT_PROPRIETARY_MODULE); 2407 2408 /* driverloader was caught wrongly pretending to be under GPL */ 2409 if (strcmp(mod->name, "driverloader") == 0) 2410 add_taint_module(mod, TAINT_PROPRIETARY_MODULE); 2411 2412#ifdef CONFIG_MODVERSIONS 2413 if ((mod->num_syms && !mod->crcs) 2414 || (mod->num_gpl_syms && !mod->gpl_crcs) 2415 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) 2416#ifdef CONFIG_UNUSED_SYMBOLS 2417 || (mod->num_unused_syms && !mod->unused_crcs) 2418 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) 2419#endif 2420 ) { 2421 return try_to_force_load(mod, 2422 "no versions for exported symbols"); 2423 } 2424#endif 2425 return 0; 2426} 2427 2428static void flush_module_icache(const struct module *mod) 2429{ 2430 mm_segment_t old_fs; 2431 2432 /* flush the icache in correct context */ 2433 old_fs = get_fs(); 2434 set_fs(KERNEL_DS); 2435 2436 /* 2437 * Flush the instruction cache, since we've played with text. 2438 * Do it before processing of module parameters, so the module 2439 * can provide parameter accessor functions of its own. 2440 */ 2441 if (mod->module_init) 2442 flush_icache_range((unsigned long)mod->module_init, 2443 (unsigned long)mod->module_init 2444 + mod->init_size); 2445 flush_icache_range((unsigned long)mod->module_core, 2446 (unsigned long)mod->module_core + mod->core_size); 2447 2448 set_fs(old_fs); 2449} 2450 2451static struct module *layout_and_allocate(struct load_info *info) 2452{ 2453 /* Module within temporary copy. */ 2454 struct module *mod; 2455 Elf_Shdr *pcpusec; 2456 int err; 2457 2458 mod = setup_load_info(info); 2459 if (IS_ERR(mod)) 2460 return mod; 2461 2462 err = check_modinfo(mod, info); 2463 if (err) 2464 return ERR_PTR(err); 2465 2466 /* Allow arches to frob section contents and sizes. */ 2467 err = module_frob_arch_sections(info->hdr, info->sechdrs, 2468 info->secstrings, mod); 2469 if (err < 0) 2470 goto out; 2471 2472 pcpusec = &info->sechdrs[info->index.pcpu]; 2473 if (pcpusec->sh_size) { 2474 /* We have a special allocation for this section. */ 2475 err = percpu_modalloc(mod, 2476 pcpusec->sh_size, pcpusec->sh_addralign); 2477 if (err) 2478 goto out; 2479 pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC; 2480 } 2481 2482 /* Determine total sizes, and put offsets in sh_entsize. For now 2483 this is done generically; there doesn't appear to be any 2484 special cases for the architectures. */ 2485 layout_sections(mod, info); 2486 2487 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size) 2488 * sizeof(long), GFP_KERNEL); 2489 if (!info->strmap) { 2490 err = -ENOMEM; 2491 goto free_percpu; 2492 } 2493 layout_symtab(mod, info); 2494 2495 /* Allocate and move to the final place */ 2496 err = move_module(mod, info); 2497 if (err) 2498 goto free_strmap; 2499 2500 /* Module has been copied to its final place now: return it. */ 2501 mod = (void *)info->sechdrs[info->index.mod].sh_addr; 2502 kmemleak_load_module(mod, info); 2503 return mod; 2504 2505free_strmap: 2506 kfree(info->strmap); 2507free_percpu: 2508 percpu_modfree(mod); 2509out: 2510 return ERR_PTR(err); 2511} 2512 2513/* mod is no longer valid after this! */ 2514static void module_deallocate(struct module *mod, struct load_info *info) 2515{ 2516 kfree(info->strmap); 2517 percpu_modfree(mod); 2518 module_free(mod, mod->module_init); 2519 module_free(mod, mod->module_core); 2520} 2521 2522static int post_relocation(struct module *mod, const struct load_info *info) 2523{ 2524 /* Sort exception table now relocations are done. */ 2525 sort_extable(mod->extable, mod->extable + mod->num_exentries); 2526 2527 /* Copy relocated percpu area over. */ 2528 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, 2529 info->sechdrs[info->index.pcpu].sh_size); 2530 2531 /* Setup kallsyms-specific fields. */ 2532 add_kallsyms(mod, info); 2533 2534 /* Arch-specific module finalizing. */ 2535 return module_finalize(info->hdr, info->sechdrs, mod); 2536} 2537 2538/* Allocate and load the module: note that size of section 0 is always 2539 zero, and we rely on this for optional sections. */ 2540static struct module *load_module(void __user *umod, 2541 unsigned long len, 2542 const char __user *uargs) 2543{ 2544 struct load_info info = { NULL, }; 2545 struct module *mod; 2546 long err; 2547 2548 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", 2549 umod, len, uargs); 2550 2551 /* Copy in the blobs from userspace, check they are vaguely sane. */ 2552 err = copy_and_check(&info, umod, len, uargs); 2553 if (err) 2554 return ERR_PTR(err); 2555 2556 /* Figure out module layout, and allocate all the memory. */ 2557 mod = layout_and_allocate(&info); 2558 if (IS_ERR(mod)) { 2559 err = PTR_ERR(mod); 2560 goto free_copy; 2561 } 2562 2563 /* Now module is in final location, initialize linked lists, etc. */ 2564 err = module_unload_init(mod); 2565 if (err) 2566 goto free_module; 2567 2568 /* Now we've got everything in the final locations, we can 2569 * find optional sections. */ 2570 find_module_sections(mod, &info); 2571 2572 err = check_module_license_and_versions(mod); 2573 if (err) 2574 goto free_unload; 2575 2576 /* Set up MODINFO_ATTR fields */ 2577 setup_modinfo(mod, &info); 2578 2579 /* Fix up syms, so that st_value is a pointer to location. */ 2580 err = simplify_symbols(mod, &info); 2581 if (err < 0) 2582 goto free_modinfo; 2583 2584 err = apply_relocations(mod, &info); 2585 if (err < 0) 2586 goto free_modinfo; 2587 2588 err = post_relocation(mod, &info); 2589 if (err < 0) 2590 goto free_modinfo; 2591 2592 flush_module_icache(mod); 2593 2594 /* Now copy in args */ 2595 mod->args = strndup_user(uargs, ~0UL >> 1); 2596 if (IS_ERR(mod->args)) { 2597 err = PTR_ERR(mod->args); 2598 goto free_arch_cleanup; 2599 } 2600 2601 /* Mark state as coming so strong_try_module_get() ignores us. */ 2602 mod->state = MODULE_STATE_COMING; 2603 2604 /* Now sew it into the lists so we can get lockdep and oops 2605 * info during argument parsing. Noone should access us, since 2606 * strong_try_module_get() will fail. 2607 * lockdep/oops can run asynchronous, so use the RCU list insertion 2608 * function to insert in a way safe to concurrent readers. 2609 * The mutex protects against concurrent writers. 2610 */ 2611 mutex_lock(&module_mutex); 2612 if (find_module(mod->name)) { 2613 err = -EEXIST; 2614 goto unlock; 2615 } 2616 2617 /* This has to be done once we're sure module name is unique. */ 2618 if (!mod->taints) 2619 dynamic_debug_setup(info.debug, info.num_debug); 2620 2621 /* Find duplicate symbols */ 2622 err = verify_export_symbols(mod); 2623 if (err < 0) 2624 goto ddebug; 2625 2626 module_bug_finalize(info.hdr, info.sechdrs, mod); 2627 list_add_rcu(&mod->list, &modules); 2628 mutex_unlock(&module_mutex); 2629 2630 /* Module is ready to execute: parsing args may do that. */ 2631 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL); 2632 if (err < 0) 2633 goto unlink; 2634 2635 /* Link in to syfs. */ 2636 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp); 2637 if (err < 0) 2638 goto unlink; 2639 2640 /* Get rid of temporary copy and strmap. */ 2641 kfree(info.strmap); 2642 free_copy(&info); 2643 2644 /* Done! */ 2645 trace_module_load(mod); 2646 return mod; 2647 2648 unlink: 2649 mutex_lock(&module_mutex); 2650 /* Unlink carefully: kallsyms could be walking list. */ 2651 list_del_rcu(&mod->list); 2652 module_bug_cleanup(mod); 2653 2654 ddebug: 2655 if (!mod->taints) 2656 dynamic_debug_remove(info.debug); 2657 unlock: 2658 mutex_unlock(&module_mutex); 2659 synchronize_sched(); 2660 kfree(mod->args); 2661 free_arch_cleanup: 2662 module_arch_cleanup(mod); 2663 free_modinfo: 2664 free_modinfo(mod); 2665 free_unload: 2666 module_unload_free(mod); 2667 free_module: 2668 module_deallocate(mod, &info); 2669 free_copy: 2670 free_copy(&info); 2671 return ERR_PTR(err); 2672} 2673 2674/* Call module constructors. */ 2675static void do_mod_ctors(struct module *mod) 2676{ 2677#ifdef CONFIG_CONSTRUCTORS 2678 unsigned long i; 2679 2680 for (i = 0; i < mod->num_ctors; i++) 2681 mod->ctors[i](); 2682#endif 2683} 2684 2685/* This is where the real work happens */ 2686SYSCALL_DEFINE3(init_module, void __user *, umod, 2687 unsigned long, len, const char __user *, uargs) 2688{ 2689 struct module *mod; 2690 int ret = 0; 2691 2692 /* Must have permission */ 2693 if (!capable(CAP_SYS_MODULE) || modules_disabled) 2694 return -EPERM; 2695 2696 /* Do all the hard work */ 2697 mod = load_module(umod, len, uargs); 2698 if (IS_ERR(mod)) 2699 return PTR_ERR(mod); 2700 2701 blocking_notifier_call_chain(&module_notify_list, 2702 MODULE_STATE_COMING, mod); 2703 2704 do_mod_ctors(mod); 2705 /* Start the module */ 2706 if (mod->init != NULL) 2707 ret = do_one_initcall(mod->init); 2708 if (ret < 0) { 2709 /* Init routine failed: abort. Try to protect us from 2710 buggy refcounters. */ 2711 mod->state = MODULE_STATE_GOING; 2712 synchronize_sched(); 2713 module_put(mod); 2714 blocking_notifier_call_chain(&module_notify_list, 2715 MODULE_STATE_GOING, mod); 2716 free_module(mod); 2717 wake_up(&module_wq); 2718 return ret; 2719 } 2720 if (ret > 0) { 2721 printk(KERN_WARNING 2722"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n" 2723"%s: loading module anyway...\n", 2724 __func__, mod->name, ret, 2725 __func__); 2726 dump_stack(); 2727 } 2728 2729 /* Now it's a first class citizen! Wake up anyone waiting for it. */ 2730 mod->state = MODULE_STATE_LIVE; 2731 wake_up(&module_wq); 2732 blocking_notifier_call_chain(&module_notify_list, 2733 MODULE_STATE_LIVE, mod); 2734 2735 /* We need to finish all async code before the module init sequence is done */ 2736 async_synchronize_full(); 2737 2738 mutex_lock(&module_mutex); 2739 /* Drop initial reference. */ 2740 module_put(mod); 2741 trim_init_extable(mod); 2742#ifdef CONFIG_KALLSYMS 2743 mod->num_symtab = mod->core_num_syms; 2744 mod->symtab = mod->core_symtab; 2745 mod->strtab = mod->core_strtab; 2746#endif 2747 module_free(mod, mod->module_init); 2748 mod->module_init = NULL; 2749 mod->init_size = 0; 2750 mod->init_text_size = 0; 2751 mutex_unlock(&module_mutex); 2752 2753 return 0; 2754} 2755 2756static inline int within(unsigned long addr, void *start, unsigned long size) 2757{ 2758 return ((void *)addr >= start && (void *)addr < start + size); 2759} 2760 2761#ifdef CONFIG_KALLSYMS 2762/* 2763 * This ignores the intensely annoying "mapping symbols" found 2764 * in ARM ELF files: $a, $t and $d. 2765 */ 2766static inline int is_arm_mapping_symbol(const char *str) 2767{ 2768 return str[0] == '$' && strchr("atd", str[1]) 2769 && (str[2] == '\0' || str[2] == '.'); 2770} 2771 2772static const char *get_ksymbol(struct module *mod, 2773 unsigned long addr, 2774 unsigned long *size, 2775 unsigned long *offset) 2776{ 2777 unsigned int i, best = 0; 2778 unsigned long nextval; 2779 2780 /* At worse, next value is at end of module */ 2781 if (within_module_init(addr, mod)) 2782 nextval = (unsigned long)mod->module_init+mod->init_text_size; 2783 else 2784 nextval = (unsigned long)mod->module_core+mod->core_text_size; 2785 2786 /* Scan for closest preceeding symbol, and next symbol. (ELF 2787 starts real symbols at 1). */ 2788 for (i = 1; i < mod->num_symtab; i++) { 2789 if (mod->symtab[i].st_shndx == SHN_UNDEF) 2790 continue; 2791 2792 /* We ignore unnamed symbols: they're uninformative 2793 * and inserted at a whim. */ 2794 if (mod->symtab[i].st_value <= addr 2795 && mod->symtab[i].st_value > mod->symtab[best].st_value 2796 && *(mod->strtab + mod->symtab[i].st_name) != '\0' 2797 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) 2798 best = i; 2799 if (mod->symtab[i].st_value > addr 2800 && mod->symtab[i].st_value < nextval 2801 && *(mod->strtab + mod->symtab[i].st_name) != '\0' 2802 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) 2803 nextval = mod->symtab[i].st_value; 2804 } 2805 2806 if (!best) 2807 return NULL; 2808 2809 if (size) 2810 *size = nextval - mod->symtab[best].st_value; 2811 if (offset) 2812 *offset = addr - mod->symtab[best].st_value; 2813 return mod->strtab + mod->symtab[best].st_name; 2814} 2815 2816/* For kallsyms to ask for address resolution. NULL means not found. Careful 2817 * not to lock to avoid deadlock on oopses, simply disable preemption. */ 2818const char *module_address_lookup(unsigned long addr, 2819 unsigned long *size, 2820 unsigned long *offset, 2821 char **modname, 2822 char *namebuf) 2823{ 2824 struct module *mod; 2825 const char *ret = NULL; 2826 2827 preempt_disable(); 2828 list_for_each_entry_rcu(mod, &modules, list) { 2829 if (within_module_init(addr, mod) || 2830 within_module_core(addr, mod)) { 2831 if (modname) 2832 *modname = mod->name; 2833 ret = get_ksymbol(mod, addr, size, offset); 2834 break; 2835 } 2836 } 2837 /* Make a copy in here where it's safe */ 2838 if (ret) { 2839 strncpy(namebuf, ret, KSYM_NAME_LEN - 1); 2840 ret = namebuf; 2841 } 2842 preempt_enable(); 2843 return ret; 2844} 2845 2846int lookup_module_symbol_name(unsigned long addr, char *symname) 2847{ 2848 struct module *mod; 2849 2850 preempt_disable(); 2851 list_for_each_entry_rcu(mod, &modules, list) { 2852 if (within_module_init(addr, mod) || 2853 within_module_core(addr, mod)) { 2854 const char *sym; 2855 2856 sym = get_ksymbol(mod, addr, NULL, NULL); 2857 if (!sym) 2858 goto out; 2859 strlcpy(symname, sym, KSYM_NAME_LEN); 2860 preempt_enable(); 2861 return 0; 2862 } 2863 } 2864out: 2865 preempt_enable(); 2866 return -ERANGE; 2867} 2868 2869int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, 2870 unsigned long *offset, char *modname, char *name) 2871{ 2872 struct module *mod; 2873 2874 preempt_disable(); 2875 list_for_each_entry_rcu(mod, &modules, list) { 2876 if (within_module_init(addr, mod) || 2877 within_module_core(addr, mod)) { 2878 const char *sym; 2879 2880 sym = get_ksymbol(mod, addr, size, offset); 2881 if (!sym) 2882 goto out; 2883 if (modname) 2884 strlcpy(modname, mod->name, MODULE_NAME_LEN); 2885 if (name) 2886 strlcpy(name, sym, KSYM_NAME_LEN); 2887 preempt_enable(); 2888 return 0; 2889 } 2890 } 2891out: 2892 preempt_enable(); 2893 return -ERANGE; 2894} 2895 2896int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 2897 char *name, char *module_name, int *exported) 2898{ 2899 struct module *mod; 2900 2901 preempt_disable(); 2902 list_for_each_entry_rcu(mod, &modules, list) { 2903 if (symnum < mod->num_symtab) { 2904 *value = mod->symtab[symnum].st_value; 2905 *type = mod->symtab[symnum].st_info; 2906 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, 2907 KSYM_NAME_LEN); 2908 strlcpy(module_name, mod->name, MODULE_NAME_LEN); 2909 *exported = is_exported(name, *value, mod); 2910 preempt_enable(); 2911 return 0; 2912 } 2913 symnum -= mod->num_symtab; 2914 } 2915 preempt_enable(); 2916 return -ERANGE; 2917} 2918 2919static unsigned long mod_find_symname(struct module *mod, const char *name) 2920{ 2921 unsigned int i; 2922 2923 for (i = 0; i < mod->num_symtab; i++) 2924 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 && 2925 mod->symtab[i].st_info != 'U') 2926 return mod->symtab[i].st_value; 2927 return 0; 2928} 2929 2930/* Look for this name: can be of form module:name. */ 2931unsigned long module_kallsyms_lookup_name(const char *name) 2932{ 2933 struct module *mod; 2934 char *colon; 2935 unsigned long ret = 0; 2936 2937 /* Don't lock: we're in enough trouble already. */ 2938 preempt_disable(); 2939 if ((colon = strchr(name, ':')) != NULL) { 2940 *colon = '\0'; 2941 if ((mod = find_module(name)) != NULL) 2942 ret = mod_find_symname(mod, colon+1); 2943 *colon = ':'; 2944 } else { 2945 list_for_each_entry_rcu(mod, &modules, list) 2946 if ((ret = mod_find_symname(mod, name)) != 0) 2947 break; 2948 } 2949 preempt_enable(); 2950 return ret; 2951} 2952 2953int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, 2954 struct module *, unsigned long), 2955 void *data) 2956{ 2957 struct module *mod; 2958 unsigned int i; 2959 int ret; 2960 2961 list_for_each_entry(mod, &modules, list) { 2962 for (i = 0; i < mod->num_symtab; i++) { 2963 ret = fn(data, mod->strtab + mod->symtab[i].st_name, 2964 mod, mod->symtab[i].st_value); 2965 if (ret != 0) 2966 return ret; 2967 } 2968 } 2969 return 0; 2970} 2971#endif /* CONFIG_KALLSYMS */ 2972 2973static char *module_flags(struct module *mod, char *buf) 2974{ 2975 int bx = 0; 2976 2977 if (mod->taints || 2978 mod->state == MODULE_STATE_GOING || 2979 mod->state == MODULE_STATE_COMING) { 2980 buf[bx++] = '('; 2981 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) 2982 buf[bx++] = 'P'; 2983 if (mod->taints & (1 << TAINT_FORCED_MODULE)) 2984 buf[bx++] = 'F'; 2985 if (mod->taints & (1 << TAINT_CRAP)) 2986 buf[bx++] = 'C'; 2987 /* 2988 * TAINT_FORCED_RMMOD: could be added. 2989 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't 2990 * apply to modules. 2991 */ 2992 2993 /* Show a - for module-is-being-unloaded */ 2994 if (mod->state == MODULE_STATE_GOING) 2995 buf[bx++] = '-'; 2996 /* Show a + for module-is-being-loaded */ 2997 if (mod->state == MODULE_STATE_COMING) 2998 buf[bx++] = '+'; 2999 buf[bx++] = ')'; 3000 } 3001 buf[bx] = '\0'; 3002 3003 return buf; 3004} 3005 3006#ifdef CONFIG_PROC_FS 3007/* Called by the /proc file system to return a list of modules. */ 3008static void *m_start(struct seq_file *m, loff_t *pos) 3009{ 3010 mutex_lock(&module_mutex); 3011 return seq_list_start(&modules, *pos); 3012} 3013 3014static void *m_next(struct seq_file *m, void *p, loff_t *pos) 3015{ 3016 return seq_list_next(p, &modules, pos); 3017} 3018 3019static void m_stop(struct seq_file *m, void *p) 3020{ 3021 mutex_unlock(&module_mutex); 3022} 3023 3024static int m_show(struct seq_file *m, void *p) 3025{ 3026 struct module *mod = list_entry(p, struct module, list); 3027 char buf[8]; 3028 3029 seq_printf(m, "%s %u", 3030 mod->name, mod->init_size + mod->core_size); 3031 print_unload_info(m, mod); 3032 3033 /* Informative for users. */ 3034 seq_printf(m, " %s", 3035 mod->state == MODULE_STATE_GOING ? "Unloading": 3036 mod->state == MODULE_STATE_COMING ? "Loading": 3037 "Live"); 3038 /* Used by oprofile and other similar tools. */ 3039 seq_printf(m, " 0x%p", mod->module_core); 3040 3041 /* Taints info */ 3042 if (mod->taints) 3043 seq_printf(m, " %s", module_flags(mod, buf)); 3044 3045 seq_printf(m, "\n"); 3046 return 0; 3047} 3048 3049/* Format: modulename size refcount deps address 3050 3051 Where refcount is a number or -, and deps is a comma-separated list 3052 of depends or -. 3053*/ 3054static const struct seq_operations modules_op = { 3055 .start = m_start, 3056 .next = m_next, 3057 .stop = m_stop, 3058 .show = m_show 3059}; 3060 3061static int modules_open(struct inode *inode, struct file *file) 3062{ 3063 return seq_open(file, &modules_op); 3064} 3065 3066static const struct file_operations proc_modules_operations = { 3067 .open = modules_open, 3068 .read = seq_read, 3069 .llseek = seq_lseek, 3070 .release = seq_release, 3071}; 3072 3073static int __init proc_modules_init(void) 3074{ 3075 proc_create("modules", 0, NULL, &proc_modules_operations); 3076 return 0; 3077} 3078module_init(proc_modules_init); 3079#endif 3080 3081/* Given an address, look for it in the module exception tables. */ 3082const struct exception_table_entry *search_module_extables(unsigned long addr) 3083{ 3084 const struct exception_table_entry *e = NULL; 3085 struct module *mod; 3086 3087 preempt_disable(); 3088 list_for_each_entry_rcu(mod, &modules, list) { 3089 if (mod->num_exentries == 0) 3090 continue; 3091 3092 e = search_extable(mod->extable, 3093 mod->extable + mod->num_exentries - 1, 3094 addr); 3095 if (e) 3096 break; 3097 } 3098 preempt_enable(); 3099 3100 /* Now, if we found one, we are running inside it now, hence 3101 we cannot unload the module, hence no refcnt needed. */ 3102 return e; 3103} 3104 3105/* 3106 * is_module_address - is this address inside a module? 3107 * @addr: the address to check. 3108 * 3109 * See is_module_text_address() if you simply want to see if the address 3110 * is code (not data). 3111 */ 3112bool is_module_address(unsigned long addr) 3113{ 3114 bool ret; 3115 3116 preempt_disable(); 3117 ret = __module_address(addr) != NULL; 3118 preempt_enable(); 3119 3120 return ret; 3121} 3122 3123/* 3124 * __module_address - get the module which contains an address. 3125 * @addr: the address. 3126 * 3127 * Must be called with preempt disabled or module mutex held so that 3128 * module doesn't get freed during this. 3129 */ 3130struct module *__module_address(unsigned long addr) 3131{ 3132 struct module *mod; 3133 3134 if (addr < module_addr_min || addr > module_addr_max) 3135 return NULL; 3136 3137 list_for_each_entry_rcu(mod, &modules, list) 3138 if (within_module_core(addr, mod) 3139 || within_module_init(addr, mod)) 3140 return mod; 3141 return NULL; 3142} 3143EXPORT_SYMBOL_GPL(__module_address); 3144 3145/* 3146 * is_module_text_address - is this address inside module code? 3147 * @addr: the address to check. 3148 * 3149 * See is_module_address() if you simply want to see if the address is 3150 * anywhere in a module. See kernel_text_address() for testing if an 3151 * address corresponds to kernel or module code. 3152 */ 3153bool is_module_text_address(unsigned long addr) 3154{ 3155 bool ret; 3156 3157 preempt_disable(); 3158 ret = __module_text_address(addr) != NULL; 3159 preempt_enable(); 3160 3161 return ret; 3162} 3163 3164/* 3165 * __module_text_address - get the module whose code contains an address. 3166 * @addr: the address. 3167 * 3168 * Must be called with preempt disabled or module mutex held so that 3169 * module doesn't get freed during this. 3170 */ 3171struct module *__module_text_address(unsigned long addr) 3172{ 3173 struct module *mod = __module_address(addr); 3174 if (mod) { 3175 /* Make sure it's within the text section. */ 3176 if (!within(addr, mod->module_init, mod->init_text_size) 3177 && !within(addr, mod->module_core, mod->core_text_size)) 3178 mod = NULL; 3179 } 3180 return mod; 3181} 3182EXPORT_SYMBOL_GPL(__module_text_address); 3183 3184/* Don't grab lock, we're oopsing. */ 3185void print_modules(void) 3186{ 3187 struct module *mod; 3188 char buf[8]; 3189 3190 /* Show each module name and core base address for 3191 * GDB source code trace dump 3192 */ 3193 preempt_disable(); 3194 list_for_each_entry_rcu(mod, &modules, list) { 3195 printk("module: %s\t %p\t %u\n", 3196 mod->name, 3197 mod->module_core, 3198 mod->init_size + mod->core_size); 3199 } 3200 preempt_enable(); 3201 3202 printk(KERN_DEFAULT "Modules linked in:"); 3203 /* Most callers should already have preempt disabled, but make sure */ 3204 preempt_disable(); 3205 list_for_each_entry_rcu(mod, &modules, list) 3206 printk(" %s%s", mod->name, module_flags(mod, buf)); 3207 preempt_enable(); 3208 if (last_unloaded_module[0]) 3209 printk(" [last unloaded: %s]", last_unloaded_module); 3210 printk("\n"); 3211} 3212 3213#ifdef CONFIG_MODVERSIONS 3214/* Generate the signature for all relevant module structures here. 3215 * If these change, we don't want to try to parse the module. */ 3216void module_layout(struct module *mod, 3217 struct modversion_info *ver, 3218 struct kernel_param *kp, 3219 struct kernel_symbol *ks, 3220 struct tracepoint *tp) 3221{ 3222} 3223EXPORT_SYMBOL(module_layout); 3224#endif 3225 3226#ifdef CONFIG_TRACEPOINTS 3227void module_update_tracepoints(void) 3228{ 3229 struct module *mod; 3230 3231 mutex_lock(&module_mutex); 3232 list_for_each_entry(mod, &modules, list) 3233 if (!mod->taints) 3234 tracepoint_update_probe_range(mod->tracepoints, 3235 mod->tracepoints + mod->num_tracepoints); 3236 mutex_unlock(&module_mutex); 3237} 3238 3239/* 3240 * Returns 0 if current not found. 3241 * Returns 1 if current found. 3242 */ 3243int module_get_iter_tracepoints(struct tracepoint_iter *iter) 3244{ 3245 struct module *iter_mod; 3246 int found = 0; 3247 3248 mutex_lock(&module_mutex); 3249 list_for_each_entry(iter_mod, &modules, list) { 3250 if (!iter_mod->taints) { 3251 /* 3252 * Sorted module list 3253 */ 3254 if (iter_mod < iter->module) 3255 continue; 3256 else if (iter_mod > iter->module) 3257 iter->tracepoint = NULL; 3258 found = tracepoint_get_iter_range(&iter->tracepoint, 3259 iter_mod->tracepoints, 3260 iter_mod->tracepoints 3261 + iter_mod->num_tracepoints); 3262 if (found) { 3263 iter->module = iter_mod; 3264 break; 3265 } 3266 } 3267 } 3268 mutex_unlock(&module_mutex); 3269 return found; 3270} 3271#endif 3272