diff options
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 2821 |
1 files changed, 2821 insertions, 0 deletions
diff --git a/kernel/module.c b/kernel/module.c new file mode 100644 index 0000000..79fd4d2 --- /dev/null +++ b/kernel/module.c @@ -0,0 +1,2821 @@ +/* + Copyright (C) 2002 Richard Henderson + Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ +#include <linux/module.h> +#include <linux/moduleloader.h> +#include <linux/init.h> +#include <linux/kallsyms.h> +#include <linux/fs.h> +#include <linux/sysfs.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/elf.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/syscalls.h> +#include <linux/fcntl.h> +#include <linux/rcupdate.h> +#include <linux/capability.h> +#include <linux/cpu.h> +#include <linux/moduleparam.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/vermagic.h> +#include <linux/notifier.h> +#include <linux/sched.h> +#include <linux/stop_machine.h> +#include <linux/device.h> +#include <linux/string.h> +#include <linux/mutex.h> +#include <linux/unwind.h> +#include <linux/rculist.h> +#include <asm/uaccess.h> +#include <asm/cacheflush.h> +#include <linux/license.h> +#include <asm/sections.h> +#include <linux/tracepoint.h> +#include <linux/ftrace.h> + +#if 0 +#define DEBUGP printk +#else +#define DEBUGP(fmt , a...) +#endif + +#ifndef ARCH_SHF_SMALL +#define ARCH_SHF_SMALL 0 +#endif + +/* If this is set, the section belongs in the init part of the module */ +#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) + +/* List of modules, protected by module_mutex or preempt_disable + * (delete uses stop_machine/add uses RCU list operations). */ +static DEFINE_MUTEX(module_mutex); +static LIST_HEAD(modules); + +/* Waiting for a module to finish initializing? */ +static DECLARE_WAIT_QUEUE_HEAD(module_wq); + +static BLOCKING_NOTIFIER_HEAD(module_notify_list); + +/* Bounds of module allocation, for speeding __module_text_address */ +static unsigned long module_addr_min = -1UL, module_addr_max = 0; + +int register_module_notifier(struct notifier_block * nb) +{ + return blocking_notifier_chain_register(&module_notify_list, nb); +} +EXPORT_SYMBOL(register_module_notifier); + +int unregister_module_notifier(struct notifier_block * nb) +{ + return blocking_notifier_chain_unregister(&module_notify_list, nb); +} +EXPORT_SYMBOL(unregister_module_notifier); + +/* We require a truly strong try_module_get(): 0 means failure due to + ongoing or failed initialization etc. */ +static inline int strong_try_module_get(struct module *mod) +{ + if (mod && mod->state == MODULE_STATE_COMING) + return -EBUSY; + if (try_module_get(mod)) + return 0; + else + return -ENOENT; +} + +static inline void add_taint_module(struct module *mod, unsigned flag) +{ + add_taint(flag); + mod->taints |= (1U << flag); +} + +/* + * A thread that wants to hold a reference to a module only while it + * is running can call this to safely exit. nfsd and lockd use this. + */ +void __module_put_and_exit(struct module *mod, long code) +{ + module_put(mod); + do_exit(code); +} +EXPORT_SYMBOL(__module_put_and_exit); + +/* Find a module section: 0 means not found. */ +static unsigned int find_sec(Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + const char *secstrings, + const char *name) +{ + unsigned int i; + + for (i = 1; i < hdr->e_shnum; i++) + /* Alloc bit cleared means "ignore it." */ + if ((sechdrs[i].sh_flags & SHF_ALLOC) + && strcmp(secstrings+sechdrs[i].sh_name, name) == 0) + return i; + return 0; +} + +/* Find a module section, or NULL. */ +static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs, + const char *secstrings, const char *name) +{ + /* Section 0 has sh_addr 0. */ + return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr; +} + +/* Find a module section, or NULL. Fill in number of "objects" in section. */ +static void *section_objs(Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + const char *secstrings, + const char *name, + size_t object_size, + unsigned int *num) +{ + unsigned int sec = find_sec(hdr, sechdrs, secstrings, name); + + /* Section 0 has sh_addr 0 and sh_size 0. */ + *num = sechdrs[sec].sh_size / object_size; + return (void *)sechdrs[sec].sh_addr; +} + +/* Provided by the linker */ +extern const struct kernel_symbol __start___ksymtab[]; +extern const struct kernel_symbol __stop___ksymtab[]; +extern const struct kernel_symbol __start___ksymtab_gpl[]; +extern const struct kernel_symbol __stop___ksymtab_gpl[]; +extern const struct kernel_symbol __start___ksymtab_gpl_future[]; +extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; +extern const struct kernel_symbol __start___ksymtab_gpl_future[]; +extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; +extern const unsigned long __start___kcrctab[]; +extern const unsigned long __start___kcrctab_gpl[]; +extern const unsigned long __start___kcrctab_gpl_future[]; +#ifdef CONFIG_UNUSED_SYMBOLS +extern const struct kernel_symbol __start___ksymtab_unused[]; +extern const struct kernel_symbol __stop___ksymtab_unused[]; +extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; +extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; +extern const unsigned long __start___kcrctab_unused[]; +extern const unsigned long __start___kcrctab_unused_gpl[]; +#endif + +#ifndef CONFIG_MODVERSIONS +#define symversion(base, idx) NULL +#else +#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) +#endif + +struct symsearch { + const struct kernel_symbol *start, *stop; + const unsigned long *crcs; + enum { + NOT_GPL_ONLY, + GPL_ONLY, + WILL_BE_GPL_ONLY, + } licence; + bool unused; +}; + +static bool each_symbol_in_section(const struct symsearch *arr, + unsigned int arrsize, + struct module *owner, + bool (*fn)(const struct symsearch *syms, + struct module *owner, + unsigned int symnum, void *data), + void *data) +{ + unsigned int i, j; + + for (j = 0; j < arrsize; j++) { + for (i = 0; i < arr[j].stop - arr[j].start; i++) + if (fn(&arr[j], owner, i, data)) + return true; + } + + return false; +} + +/* Returns true as soon as fn returns true, otherwise false. */ +static bool each_symbol(bool (*fn)(const struct symsearch *arr, + struct module *owner, + unsigned int symnum, void *data), + void *data) +{ + struct module *mod; + const struct symsearch arr[] = { + { __start___ksymtab, __stop___ksymtab, __start___kcrctab, + NOT_GPL_ONLY, false }, + { __start___ksymtab_gpl, __stop___ksymtab_gpl, + __start___kcrctab_gpl, + GPL_ONLY, false }, + { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, + __start___kcrctab_gpl_future, + WILL_BE_GPL_ONLY, false }, +#ifdef CONFIG_UNUSED_SYMBOLS + { __start___ksymtab_unused, __stop___ksymtab_unused, + __start___kcrctab_unused, + NOT_GPL_ONLY, true }, + { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, + __start___kcrctab_unused_gpl, + GPL_ONLY, true }, +#endif + }; + + if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) + return true; + + list_for_each_entry_rcu(mod, &modules, list) { + struct symsearch arr[] = { + { mod->syms, mod->syms + mod->num_syms, mod->crcs, + NOT_GPL_ONLY, false }, + { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, + mod->gpl_crcs, + GPL_ONLY, false }, + { mod->gpl_future_syms, + mod->gpl_future_syms + mod->num_gpl_future_syms, + mod->gpl_future_crcs, + WILL_BE_GPL_ONLY, false }, +#ifdef CONFIG_UNUSED_SYMBOLS + { mod->unused_syms, + mod->unused_syms + mod->num_unused_syms, + mod->unused_crcs, + NOT_GPL_ONLY, true }, + { mod->unused_gpl_syms, + mod->unused_gpl_syms + mod->num_unused_gpl_syms, + mod->unused_gpl_crcs, + GPL_ONLY, true }, +#endif + }; + + if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) + return true; + } + return false; +} + +struct find_symbol_arg { + /* Input */ + const char *name; + bool gplok; + bool warn; + + /* Output */ + struct module *owner; + const unsigned long *crc; + unsigned long value; +}; + +static bool find_symbol_in_section(const struct symsearch *syms, + struct module *owner, + unsigned int symnum, void *data) +{ + struct find_symbol_arg *fsa = data; + + if (strcmp(syms->start[symnum].name, fsa->name) != 0) + return false; + + if (!fsa->gplok) { + if (syms->licence == GPL_ONLY) + return false; + if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { + printk(KERN_WARNING "Symbol %s is being used " + "by a non-GPL module, which will not " + "be allowed in the future\n", fsa->name); + printk(KERN_WARNING "Please see the file " + "Documentation/feature-removal-schedule.txt " + "in the kernel source tree for more details.\n"); + } + } + +#ifdef CONFIG_UNUSED_SYMBOLS + if (syms->unused && fsa->warn) { + printk(KERN_WARNING "Symbol %s is marked as UNUSED, " + "however this module is using it.\n", fsa->name); + printk(KERN_WARNING + "This symbol will go away in the future.\n"); + printk(KERN_WARNING + "Please evalute if this is the right api to use and if " + "it really is, submit a report the linux kernel " + "mailinglist together with submitting your code for " + "inclusion.\n"); + } +#endif + + fsa->owner = owner; + fsa->crc = symversion(syms->crcs, symnum); + fsa->value = syms->start[symnum].value; + return true; +} + +/* Find a symbol, return value, (optional) crc and (optional) module + * which owns it */ +static unsigned long find_symbol(const char *name, + struct module **owner, + const unsigned long **crc, + bool gplok, + bool warn) +{ + struct find_symbol_arg fsa; + + fsa.name = name; + fsa.gplok = gplok; + fsa.warn = warn; + + if (each_symbol(find_symbol_in_section, &fsa)) { + if (owner) + *owner = fsa.owner; + if (crc) + *crc = fsa.crc; + return fsa.value; + } + + DEBUGP("Failed to find symbol %s\n", name); + return -ENOENT; +} + +/* Search for module by name: must hold module_mutex. */ +static struct module *find_module(const char *name) +{ + struct module *mod; + + list_for_each_entry(mod, &modules, list) { + if (strcmp(mod->name, name) == 0) + return mod; + } + return NULL; +} + +#ifdef CONFIG_SMP +/* Number of blocks used and allocated. */ +static unsigned int pcpu_num_used, pcpu_num_allocated; +/* Size of each block. -ve means used. */ +static int *pcpu_size; + +static int split_block(unsigned int i, unsigned short size) +{ + /* Reallocation required? */ + if (pcpu_num_used + 1 > pcpu_num_allocated) { + int *new; + + new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2, + GFP_KERNEL); + if (!new) + return 0; + + pcpu_num_allocated *= 2; + pcpu_size = new; + } + + /* Insert a new subblock */ + memmove(&pcpu_size[i+1], &pcpu_size[i], + sizeof(pcpu_size[0]) * (pcpu_num_used - i)); + pcpu_num_used++; + + pcpu_size[i+1] -= size; + pcpu_size[i] = size; + return 1; +} + +static inline unsigned int block_size(int val) +{ + if (val < 0) + return -val; + return val; +} + +static void *percpu_modalloc(unsigned long size, unsigned long align, + const char *name) +{ + unsigned long extra; + unsigned int i; + void *ptr; + + if (align > PAGE_SIZE) { + printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", + name, align, PAGE_SIZE); + align = PAGE_SIZE; + } + + ptr = __per_cpu_start; + for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { + /* Extra for alignment requirement. */ + extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr; + BUG_ON(i == 0 && extra != 0); + + if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size) + continue; + + /* Transfer extra to previous block. */ + if (pcpu_size[i-1] < 0) + pcpu_size[i-1] -= extra; + else + pcpu_size[i-1] += extra; + pcpu_size[i] -= extra; + ptr += extra; + + /* Split block if warranted */ + if (pcpu_size[i] - size > sizeof(unsigned long)) + if (!split_block(i, size)) + return NULL; + + /* Mark allocated */ + pcpu_size[i] = -pcpu_size[i]; + return ptr; + } + + printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n", + size); + return NULL; +} + +static void percpu_modfree(void *freeme) +{ + unsigned int i; + void *ptr = __per_cpu_start + block_size(pcpu_size[0]); + + /* First entry is core kernel percpu data. */ + for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { + if (ptr == freeme) { + pcpu_size[i] = -pcpu_size[i]; + goto free; + } + } + BUG(); + + free: + /* Merge with previous? */ + if (pcpu_size[i-1] >= 0) { + pcpu_size[i-1] += pcpu_size[i]; + pcpu_num_used--; + memmove(&pcpu_size[i], &pcpu_size[i+1], + (pcpu_num_used - i) * sizeof(pcpu_size[0])); + i--; + } + /* Merge with next? */ + if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) { + pcpu_size[i] += pcpu_size[i+1]; + pcpu_num_used--; + memmove(&pcpu_size[i+1], &pcpu_size[i+2], + (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0])); + } +} + +static unsigned int find_pcpusec(Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + const char *secstrings) +{ + return find_sec(hdr, sechdrs, secstrings, ".data.percpu"); +} + +static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size) +{ + int cpu; + + for_each_possible_cpu(cpu) + memcpy(pcpudest + per_cpu_offset(cpu), from, size); +} + +static int percpu_modinit(void) +{ + pcpu_num_used = 2; + pcpu_num_allocated = 2; + pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated, + GFP_KERNEL); + /* Static in-kernel percpu data (used). */ + pcpu_size[0] = -(__per_cpu_end-__per_cpu_start); + /* Free room. */ + pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0]; + if (pcpu_size[1] < 0) { + printk(KERN_ERR "No per-cpu room for modules.\n"); + pcpu_num_used = 1; + } + + return 0; +} +__initcall(percpu_modinit); +#else /* ... !CONFIG_SMP */ +static inline void *percpu_modalloc(unsigned long size, unsigned long align, + const char *name) +{ + return NULL; +} +static inline void percpu_modfree(void *pcpuptr) +{ + BUG(); +} +static inline unsigned int find_pcpusec(Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + const char *secstrings) +{ + return 0; +} +static inline void percpu_modcopy(void *pcpudst, const void *src, + unsigned long size) +{ + /* pcpusec should be 0, and size of that section should be 0. */ + BUG_ON(size != 0); +} +#endif /* CONFIG_SMP */ + +#define MODINFO_ATTR(field) \ +static void setup_modinfo_##field(struct module *mod, const char *s) \ +{ \ + mod->field = kstrdup(s, GFP_KERNEL); \ +} \ +static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ + struct module *mod, char *buffer) \ +{ \ + return sprintf(buffer, "%s\n", mod->field); \ +} \ +static int modinfo_##field##_exists(struct module *mod) \ +{ \ + return mod->field != NULL; \ +} \ +static void free_modinfo_##field(struct module *mod) \ +{ \ + kfree(mod->field); \ + mod->field = NULL; \ +} \ +static struct module_attribute modinfo_##field = { \ + .attr = { .name = __stringify(field), .mode = 0444 }, \ + .show = show_modinfo_##field, \ + .setup = setup_modinfo_##field, \ + .test = modinfo_##field##_exists, \ + .free = free_modinfo_##field, \ +}; + +MODINFO_ATTR(version); +MODINFO_ATTR(srcversion); + +static char last_unloaded_module[MODULE_NAME_LEN+1]; + +#ifdef CONFIG_MODULE_UNLOAD +/* Init the unload section of the module. */ +static void module_unload_init(struct module *mod) +{ + unsigned int i; + + INIT_LIST_HEAD(&mod->modules_which_use_me); + for (i = 0; i < NR_CPUS; i++) + local_set(&mod->ref[i].count, 0); + /* Hold reference count during initialization. */ + local_set(&mod->ref[raw_smp_processor_id()].count, 1); + /* Backwards compatibility macros put refcount during init. */ + mod->waiter = current; +} + +/* modules using other modules */ +struct module_use +{ + struct list_head list; + struct module *module_which_uses; +}; + +/* Does a already use b? */ +static int already_uses(struct module *a, struct module *b) +{ + struct module_use *use; + + list_for_each_entry(use, &b->modules_which_use_me, list) { + if (use->module_which_uses == a) { + DEBUGP("%s uses %s!\n", a->name, b->name); + return 1; + } + } + DEBUGP("%s does not use %s!\n", a->name, b->name); + return 0; +} + +/* Module a uses b */ +static int use_module(struct module *a, struct module *b) +{ + struct module_use *use; + int no_warn, err; + + if (b == NULL || already_uses(a, b)) return 1; + + /* If we're interrupted or time out, we fail. */ + if (wait_event_interruptible_timeout( + module_wq, (err = strong_try_module_get(b)) != -EBUSY, + 30 * HZ) <= 0) { + printk("%s: gave up waiting for init of module %s.\n", + a->name, b->name); + return 0; + } + + /* If strong_try_module_get() returned a different error, we fail. */ + if (err) + return 0; + + DEBUGP("Allocating new usage for %s.\n", a->name); + use = kmalloc(sizeof(*use), GFP_ATOMIC); + if (!use) { + printk("%s: out of memory loading\n", a->name); + module_put(b); + return 0; + } + + use->module_which_uses = a; + list_add(&use->list, &b->modules_which_use_me); + no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name); + return 1; +} + +/* Clear the unload stuff of the module. */ +static void module_unload_free(struct module *mod) +{ + struct module *i; + + list_for_each_entry(i, &modules, list) { + struct module_use *use; + + list_for_each_entry(use, &i->modules_which_use_me, list) { + if (use->module_which_uses == mod) { + DEBUGP("%s unusing %s\n", mod->name, i->name); + module_put(i); + list_del(&use->list); + kfree(use); + sysfs_remove_link(i->holders_dir, mod->name); + /* There can be at most one match. */ + break; + } + } + } +} + +#ifdef CONFIG_MODULE_FORCE_UNLOAD +static inline int try_force_unload(unsigned int flags) +{ + int ret = (flags & O_TRUNC); + if (ret) + add_taint(TAINT_FORCED_RMMOD); + return ret; +} +#else +static inline int try_force_unload(unsigned int flags) +{ + return 0; +} +#endif /* CONFIG_MODULE_FORCE_UNLOAD */ + +struct stopref +{ + struct module *mod; + int flags; + int *forced; +}; + +/* Whole machine is stopped with interrupts off when this runs. */ +static int __try_stop_module(void *_sref) +{ + struct stopref *sref = _sref; + + /* If it's not unused, quit unless we're forcing. */ + if (module_refcount(sref->mod) != 0) { + if (!(*sref->forced = try_force_unload(sref->flags))) + return -EWOULDBLOCK; + } + + /* Mark it as dying. */ + sref->mod->state = MODULE_STATE_GOING; + return 0; +} + +static int try_stop_module(struct module *mod, int flags, int *forced) +{ + if (flags & O_NONBLOCK) { + struct stopref sref = { mod, flags, forced }; + + return stop_machine(__try_stop_module, &sref, NULL); + } else { + /* We don't need to stop the machine for this. */ + mod->state = MODULE_STATE_GOING; + synchronize_sched(); + return 0; + } +} + +unsigned int module_refcount(struct module *mod) +{ + unsigned int i, total = 0; + + for (i = 0; i < NR_CPUS; i++) + total += local_read(&mod->ref[i].count); + return total; +} +EXPORT_SYMBOL(module_refcount); + +/* This exists whether we can unload or not */ +static void free_module(struct module *mod); + +static void wait_for_zero_refcount(struct module *mod) +{ + /* Since we might sleep for some time, release the mutex first */ + mutex_unlock(&module_mutex); + for (;;) { + DEBUGP("Looking at refcount...\n"); + set_current_state(TASK_UNINTERRUPTIBLE); + if (module_refcount(mod) == 0) + break; + schedule(); + } + current->state = TASK_RUNNING; + mutex_lock(&module_mutex); +} + +SYSCALL_DEFINE2(delete_module, const char __user *, name_user, + unsigned int, flags) +{ + struct module *mod; + char name[MODULE_NAME_LEN]; + int ret, forced = 0; + + if (!capable(CAP_SYS_MODULE)) + return -EPERM; + + if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) + return -EFAULT; + name[MODULE_NAME_LEN-1] = '\0'; + + if (mutex_lock_interruptible(&module_mutex) != 0) + return -EINTR; + + mod = find_module(name); + if (!mod) { + ret = -ENOENT; + goto out; + } + + if (!list_empty(&mod->modules_which_use_me)) { + /* Other modules depend on us: get rid of them first. */ + ret = -EWOULDBLOCK; + goto out; + } + + /* Doing init or already dying? */ + if (mod->state != MODULE_STATE_LIVE) { + /* FIXME: if (force), slam module count and wake up + waiter --RR */ + DEBUGP("%s already dying\n", mod->name); + ret = -EBUSY; + goto out; + } + + /* If it has an init func, it must have an exit func to unload */ + if (mod->init && !mod->exit) { + forced = try_force_unload(flags); + if (!forced) { + /* This module can't be removed */ + ret = -EBUSY; + goto out; + } + } + + /* Set this up before setting mod->state */ + mod->waiter = current; + + /* Stop the machine so refcounts can't move and disable module. */ + ret = try_stop_module(mod, flags, &forced); + if (ret != 0) + goto out; + + /* Never wait if forced. */ + if (!forced && module_refcount(mod) != 0) + wait_for_zero_refcount(mod); + + mutex_unlock(&module_mutex); + /* Final destruction now noone is using it. */ + if (mod->exit != NULL) + mod->exit(); + blocking_notifier_call_chain(&module_notify_list, + MODULE_STATE_GOING, mod); + mutex_lock(&module_mutex); + /* Store the name of the last unloaded module for diagnostic purposes */ + strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); + unregister_dynamic_debug_module(mod->name); + free_module(mod); + + out: + mutex_unlock(&module_mutex); + return ret; +} + +static void print_unload_info(struct seq_file *m, struct module *mod) +{ + struct module_use *use; + int printed_something = 0; + + seq_printf(m, " %u ", module_refcount(mod)); + + /* Always include a trailing , so userspace can differentiate + between this and the old multi-field proc format. */ + list_for_each_entry(use, &mod->modules_which_use_me, list) { + printed_something = 1; + seq_printf(m, "%s,", use->module_which_uses->name); + } + + if (mod->init != NULL && mod->exit == NULL) { + printed_something = 1; + seq_printf(m, "[permanent],"); + } + + if (!printed_something) + seq_printf(m, "-"); +} + +void __symbol_put(const char *symbol) +{ + struct module *owner; + + preempt_disable(); + if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false))) + BUG(); + module_put(owner); + preempt_enable(); +} +EXPORT_SYMBOL(__symbol_put); + +void symbol_put_addr(void *addr) +{ + struct module *modaddr; + + if (core_kernel_text((unsigned long)addr)) + return; + + if (!(modaddr = module_text_address((unsigned long)addr))) + BUG(); + module_put(modaddr); +} +EXPORT_SYMBOL_GPL(symbol_put_addr); + +static ssize_t show_refcnt(struct module_attribute *mattr, + struct module *mod, char *buffer) +{ + return sprintf(buffer, "%u\n", module_refcount(mod)); +} + +static struct module_attribute refcnt = { + .attr = { .name = "refcnt", .mode = 0444 }, + .show = show_refcnt, +}; + +void module_put(struct module *module) +{ + if (module) { + unsigned int cpu = get_cpu(); + local_dec(&module->ref[cpu].count); + /* Maybe they're waiting for us to drop reference? */ + if (unlikely(!module_is_live(module))) + wake_up_process(module->waiter); + put_cpu(); + } +} +EXPORT_SYMBOL(module_put); + +#else /* !CONFIG_MODULE_UNLOAD */ +static void print_unload_info(struct seq_file *m, struct module *mod) +{ + /* We don't know the usage count, or what modules are using. */ + seq_printf(m, " - -"); +} + +static inline void module_unload_free(struct module *mod) +{ +} + +static inline int use_module(struct module *a, struct module *b) +{ + return strong_try_module_get(b) == 0; +} + +static inline void module_unload_init(struct module *mod) +{ +} +#endif /* CONFIG_MODULE_UNLOAD */ + +static ssize_t show_initstate(struct module_attribute *mattr, + struct module *mod, char *buffer) +{ + const char *state = "unknown"; + + switch (mod->state) { + case MODULE_STATE_LIVE: + state = "live"; + break; + case MODULE_STATE_COMING: + state = "coming"; + break; + case MODULE_STATE_GOING: + state = "going"; + break; + } + return sprintf(buffer, "%s\n", state); +} + +static struct module_attribute initstate = { + .attr = { .name = "initstate", .mode = 0444 }, + .show = show_initstate, +}; + +static struct module_attribute *modinfo_attrs[] = { + &modinfo_version, + &modinfo_srcversion, + &initstate, +#ifdef CONFIG_MODULE_UNLOAD + &refcnt, +#endif + NULL, +}; + +static const char vermagic[] = VERMAGIC_STRING; + +static int try_to_force_load(struct module *mod, const char *symname) +{ +#ifdef CONFIG_MODULE_FORCE_LOAD + if (!test_taint(TAINT_FORCED_MODULE)) + printk("%s: no version for \"%s\" found: kernel tainted.\n", + mod->name, symname); + add_taint_module(mod, TAINT_FORCED_MODULE); + return 0; +#else + return -ENOEXEC; +#endif +} + +#ifdef CONFIG_MODVERSIONS +static int check_version(Elf_Shdr *sechdrs, + unsigned int versindex, + const char *symname, + struct module *mod, + const unsigned long *crc) +{ + unsigned int i, num_versions; + struct modversion_info *versions; + + /* Exporting module didn't supply crcs? OK, we're already tainted. */ + if (!crc) + return 1; + + /* No versions at all? modprobe --force does this. */ + if (versindex == 0) + return try_to_force_load(mod, symname) == 0; + + versions = (void *) sechdrs[versindex].sh_addr; + num_versions = sechdrs[versindex].sh_size + / sizeof(struct modversion_info); + + for (i = 0; i < num_versions; i++) { + if (strcmp(versions[i].name, symname) != 0) + continue; + + if (versions[i].crc == *crc) + return 1; + DEBUGP("Found checksum %lX vs module %lX\n", + *crc, versions[i].crc); + goto bad_version; + } + + printk(KERN_WARNING "%s: no symbol version for %s\n", + mod->name, symname); + return 0; + +bad_version: + printk("%s: disagrees about version of symbol %s\n", + mod->name, symname); + return 0; +} + +static inline int check_modstruct_version(Elf_Shdr *sechdrs, + unsigned int versindex, + struct module *mod) +{ + const unsigned long *crc; + + if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false))) + BUG(); + return check_version(sechdrs, versindex, "struct_module", mod, crc); +} + +/* First part is kernel version, which we ignore if module has crcs. */ +static inline int same_magic(const char *amagic, const char *bmagic, + bool has_crcs) +{ + if (has_crcs) { + amagic += strcspn(amagic, " "); + bmagic += strcspn(bmagic, " "); + } + return strcmp(amagic, bmagic) == 0; +} +#else +static inline int check_version(Elf_Shdr *sechdrs, + unsigned int versindex, + const char *symname, + struct module *mod, + const unsigned long *crc) +{ + return 1; +} + +static inline int check_modstruct_version(Elf_Shdr *sechdrs, + unsigned int versindex, + struct module *mod) +{ + return 1; +} + +static inline int same_magic(const char *amagic, const char *bmagic, + bool has_crcs) +{ + return strcmp(amagic, bmagic) == 0; +} +#endif /* CONFIG_MODVERSIONS */ + +/* Resolve a symbol for this module. I.e. if we find one, record usage. + Must be holding module_mutex. */ +static unsigned long resolve_symbol(Elf_Shdr *sechdrs, + unsigned int versindex, + const char *name, + struct module *mod) +{ + struct module *owner; + unsigned long ret; + const unsigned long *crc; + + ret = find_symbol(name, &owner, &crc, + !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); + if (!IS_ERR_VALUE(ret)) { + /* use_module can fail due to OOM, + or module initialization or unloading */ + if (!check_version(sechdrs, versindex, name, mod, crc) || + !use_module(mod, owner)) + ret = -EINVAL; + } + return ret; +} + +/* + * /sys/module/foo/sections stuff + * J. Corbet <corbet@lwn.net> + */ +#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS) +struct module_sect_attr +{ + struct module_attribute mattr; + char *name; + unsigned long address; +}; + +struct module_sect_attrs +{ + struct attribute_group grp; + unsigned int nsections; + struct module_sect_attr attrs[0]; +}; + +static ssize_t module_sect_show(struct module_attribute *mattr, + struct module *mod, char *buf) +{ + struct module_sect_attr *sattr = + container_of(mattr, struct module_sect_attr, mattr); + return sprintf(buf, "0x%lx\n", sattr->address); +} + +static void free_sect_attrs(struct module_sect_attrs *sect_attrs) +{ + unsigned int section; + + for (section = 0; section < sect_attrs->nsections; section++) + kfree(sect_attrs->attrs[section].name); + kfree(sect_attrs); +} + +static void add_sect_attrs(struct module *mod, unsigned int nsect, + char *secstrings, Elf_Shdr *sechdrs) +{ + unsigned int nloaded = 0, i, size[2]; + struct module_sect_attrs *sect_attrs; + struct module_sect_attr *sattr; + struct attribute **gattr; + + /* Count loaded sections and allocate structures */ + for (i = 0; i < nsect; i++) + if (sechdrs[i].sh_flags & SHF_ALLOC) + nloaded++; + size[0] = ALIGN(sizeof(*sect_attrs) + + nloaded * sizeof(sect_attrs->attrs[0]), + sizeof(sect_attrs->grp.attrs[0])); + size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); + sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); + if (sect_attrs == NULL) + return; + + /* Setup section attributes. */ + sect_attrs->grp.name = "sections"; + sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; + + sect_attrs->nsections = 0; + sattr = §_attrs->attrs[0]; + gattr = §_attrs->grp.attrs[0]; + for (i = 0; i < nsect; i++) { + if (! (sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + sattr->address = sechdrs[i].sh_addr; + sattr->name = kstrdup(secstrings + sechdrs[i].sh_name, + GFP_KERNEL); + if (sattr->name == NULL) + goto out; + sect_attrs->nsections++; + sattr->mattr.show = module_sect_show; + sattr->mattr.store = NULL; + sattr->mattr.attr.name = sattr->name; + sattr->mattr.attr.mode = S_IRUGO; + *(gattr++) = &(sattr++)->mattr.attr; + } + *gattr = NULL; + + if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) + goto out; + + mod->sect_attrs = sect_attrs; + return; + out: + free_sect_attrs(sect_attrs); +} + +static void remove_sect_attrs(struct module *mod) +{ + if (mod->sect_attrs) { + sysfs_remove_group(&mod->mkobj.kobj, + &mod->sect_attrs->grp); + /* We are positive that no one is using any sect attrs + * at this point. Deallocate immediately. */ + free_sect_attrs(mod->sect_attrs); + mod->sect_attrs = NULL; + } +} + +/* + * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. + */ + +struct module_notes_attrs { + struct kobject *dir; + unsigned int notes; + struct bin_attribute attrs[0]; +}; + +static ssize_t module_notes_read(struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + /* + * The caller checked the pos and count against our size. + */ + memcpy(buf, bin_attr->private + pos, count); + return count; +} + +static void free_notes_attrs(struct module_notes_attrs *notes_attrs, + unsigned int i) +{ + if (notes_attrs->dir) { + while (i-- > 0) + sysfs_remove_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i]); + kobject_put(notes_attrs->dir); + } + kfree(notes_attrs); +} + +static void add_notes_attrs(struct module *mod, unsigned int nsect, + char *secstrings, Elf_Shdr *sechdrs) +{ + unsigned int notes, loaded, i; + struct module_notes_attrs *notes_attrs; + struct bin_attribute *nattr; + + /* Count notes sections and allocate structures. */ + notes = 0; + for (i = 0; i < nsect; i++) + if ((sechdrs[i].sh_flags & SHF_ALLOC) && + (sechdrs[i].sh_type == SHT_NOTE)) + ++notes; + + if (notes == 0) + return; + + notes_attrs = kzalloc(sizeof(*notes_attrs) + + notes * sizeof(notes_attrs->attrs[0]), + GFP_KERNEL); + if (notes_attrs == NULL) + return; + + notes_attrs->notes = notes; + nattr = ¬es_attrs->attrs[0]; + for (loaded = i = 0; i < nsect; ++i) { + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + if (sechdrs[i].sh_type == SHT_NOTE) { + nattr->attr.name = mod->sect_attrs->attrs[loaded].name; + nattr->attr.mode = S_IRUGO; + nattr->size = sechdrs[i].sh_size; + nattr->private = (void *) sechdrs[i].sh_addr; + nattr->read = module_notes_read; + ++nattr; + } + ++loaded; + } + + notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); + if (!notes_attrs->dir) + goto out; + + for (i = 0; i < notes; ++i) + if (sysfs_create_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i])) + goto out; + + mod->notes_attrs = notes_attrs; + return; + + out: + free_notes_attrs(notes_attrs, i); +} + +static void remove_notes_attrs(struct module *mod) +{ + if (mod->notes_attrs) + free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); +} + +#else + +static inline void add_sect_attrs(struct module *mod, unsigned int nsect, + char *sectstrings, Elf_Shdr *sechdrs) +{ +} + +static inline void remove_sect_attrs(struct module *mod) +{ +} + +static inline void add_notes_attrs(struct module *mod, unsigned int nsect, + char *sectstrings, Elf_Shdr *sechdrs) +{ +} + +static inline void remove_notes_attrs(struct module *mod) +{ +} +#endif + +#ifdef CONFIG_SYSFS +int module_add_modinfo_attrs(struct module *mod) +{ + struct module_attribute *attr; + struct module_attribute *temp_attr; + int error = 0; + int i; + + mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * + (ARRAY_SIZE(modinfo_attrs) + 1)), + GFP_KERNEL); + if (!mod->modinfo_attrs) + return -ENOMEM; + + temp_attr = mod->modinfo_attrs; + for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { + if (!attr->test || + (attr->test && attr->test(mod))) { + memcpy(temp_attr, attr, sizeof(*temp_attr)); + error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); + ++temp_attr; + } + } + return error; +} + +void module_remove_modinfo_attrs(struct module *mod) +{ + struct module_attribute *attr; + int i; + + for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + /* pick a field to test for end of list */ + if (!attr->attr.name) + break; + sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); + if (attr->free) + attr->free(mod); + } + kfree(mod->modinfo_attrs); +} + +int mod_sysfs_init(struct module *mod) +{ + int err; + struct kobject *kobj; + + if (!module_sysfs_initialized) { + printk(KERN_ERR "%s: module sysfs not initialized\n", + mod->name); + err = -EINVAL; + goto out; + } + + kobj = kset_find_obj(module_kset, mod->name); + if (kobj) { + printk(KERN_ERR "%s: module is already loaded\n", mod->name); + kobject_put(kobj); + err = -EINVAL; + goto out; + } + + mod->mkobj.mod = mod; + + memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); + mod->mkobj.kobj.kset = module_kset; + err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, + "%s", mod->name); + if (err) + kobject_put(&mod->mkobj.kobj); + + /* delay uevent until full sysfs population */ +out: + return err; +} + +int mod_sysfs_setup(struct module *mod, + struct kernel_param *kparam, + unsigned int num_params) +{ + int err; + + mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); + if (!mod->holders_dir) { + err = -ENOMEM; + goto out_unreg; + } + + err = module_param_sysfs_setup(mod, kparam, num_params); + if (err) + goto out_unreg_holders; + + err = module_add_modinfo_attrs(mod); + if (err) + goto out_unreg_param; + + kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); + return 0; + +out_unreg_param: + module_param_sysfs_remove(mod); +out_unreg_holders: + kobject_put(mod->holders_dir); +out_unreg: + kobject_put(&mod->mkobj.kobj); + return err; +} + +static void mod_sysfs_fini(struct module *mod) +{ + kobject_put(&mod->mkobj.kobj); +} + +#else /* CONFIG_SYSFS */ + +static void mod_sysfs_fini(struct module *mod) +{ +} + +#endif /* CONFIG_SYSFS */ + +static void mod_kobject_remove(struct module *mod) +{ + module_remove_modinfo_attrs(mod); + module_param_sysfs_remove(mod); + kobject_put(mod->mkobj.drivers_dir); + kobject_put(mod->holders_dir); + mod_sysfs_fini(mod); +} + +/* + * unlink the module with the whole machine is stopped with interrupts off + * - this defends against kallsyms not taking locks + */ +static int __unlink_module(void *_mod) +{ + struct module *mod = _mod; + list_del(&mod->list); + return 0; +} + +/* Free a module, remove from lists, etc (must hold module_mutex). */ +static void free_module(struct module *mod) +{ + /* Delete from various lists */ + stop_machine(__unlink_module, mod, NULL); + remove_notes_attrs(mod); + remove_sect_attrs(mod); + mod_kobject_remove(mod); + + unwind_remove_table(mod->unwind_info, 0); + + /* Arch-specific cleanup. */ + module_arch_cleanup(mod); + + /* Module unload stuff */ + module_unload_free(mod); + + /* release any pointers to mcount in this module */ + ftrace_release(mod->module_core, mod->core_size); + + /* This may be NULL, but that's OK */ + module_free(mod, mod->module_init); + kfree(mod->args); + if (mod->percpu) + percpu_modfree(mod->percpu); + + /* Free lock-classes: */ + lockdep_free_key_range(mod->module_core, mod->core_size); + + /* Finally, free the core (containing the module structure) */ + module_free(mod, mod->module_core); +} + +void *__symbol_get(const char *symbol) +{ + struct module *owner; + unsigned long value; + + preempt_disable(); + value = find_symbol(symbol, &owner, NULL, true, true); + if (IS_ERR_VALUE(value)) + value = 0; + else if (strong_try_module_get(owner)) + value = 0; + preempt_enable(); + + return (void *)value; +} +EXPORT_SYMBOL_GPL(__symbol_get); + +/* + * Ensure that an exported symbol [global namespace] does not already exist + * in the kernel or in some other module's exported symbol table. + */ +static int verify_export_symbols(struct module *mod) +{ + unsigned int i; + struct module *owner; + const struct kernel_symbol *s; + struct { + const struct kernel_symbol *sym; + unsigned int num; + } arr[] = { + { mod->syms, mod->num_syms }, + { mod->gpl_syms, mod->num_gpl_syms }, + { mod->gpl_future_syms, mod->num_gpl_future_syms }, +#ifdef CONFIG_UNUSED_SYMBOLS + { mod->unused_syms, mod->num_unused_syms }, + { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, +#endif + }; + + for (i = 0; i < ARRAY_SIZE(arr); i++) { + for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { + if (!IS_ERR_VALUE(find_symbol(s->name, &owner, + NULL, true, false))) { + printk(KERN_ERR + "%s: exports duplicate symbol %s" + " (owned by %s)\n", + mod->name, s->name, module_name(owner)); + return -ENOEXEC; + } + } + } + return 0; +} + +/* Change all symbols so that st_value encodes the pointer directly. */ +static int simplify_symbols(Elf_Shdr *sechdrs, + unsigned int symindex, + const char *strtab, + unsigned int versindex, + unsigned int pcpuindex, + struct module *mod) +{ + Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; + unsigned long secbase; + unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); + int ret = 0; + + for (i = 1; i < n; i++) { + switch (sym[i].st_shndx) { + case SHN_COMMON: + /* We compiled with -fno-common. These are not + supposed to happen. */ + DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name); + printk("%s: please compile with -fno-common\n", + mod->name); + ret = -ENOEXEC; + break; + + case SHN_ABS: + /* Don't need to do anything */ + DEBUGP("Absolute symbol: 0x%08lx\n", + (long)sym[i].st_value); + break; + + case SHN_UNDEF: + sym[i].st_value + = resolve_symbol(sechdrs, versindex, + strtab + sym[i].st_name, mod); + + /* Ok if resolved. */ + if (!IS_ERR_VALUE(sym[i].st_value)) + break; + /* Ok if weak. */ + if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK) + break; + + printk(KERN_WARNING "%s: Unknown symbol %s\n", + mod->name, strtab + sym[i].st_name); + ret = -ENOENT; + break; + + default: + /* Divert to percpu allocation if a percpu var. */ + if (sym[i].st_shndx == pcpuindex) + secbase = (unsigned long)mod->percpu; + else + secbase = sechdrs[sym[i].st_shndx].sh_addr; + sym[i].st_value += secbase; + break; + } + } + + return ret; +} + +/* Update size with this section: return offset. */ +static long get_offset(unsigned int *size, Elf_Shdr *sechdr) +{ + long ret; + + ret = ALIGN(*size, sechdr->sh_addralign ?: 1); + *size = ret + sechdr->sh_size; + return ret; +} + +/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld + might -- code, read-only data, read-write data, small data. Tally + sizes, and place the offsets into sh_entsize fields: high bit means it + belongs in init. */ +static void layout_sections(struct module *mod, + const Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + const char *secstrings) +{ + static unsigned long const masks[][2] = { + /* NOTE: all executable code must be the first section + * in this array; otherwise modify the text_size + * finder in the two loops below */ + { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, + { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, + { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, + { ARCH_SHF_SMALL | SHF_ALLOC, 0 } + }; + unsigned int m, i; + + for (i = 0; i < hdr->e_shnum; i++) + sechdrs[i].sh_entsize = ~0UL; + + DEBUGP("Core section allocation order:\n"); + for (m = 0; m < ARRAY_SIZE(masks); ++m) { + for (i = 0; i < hdr->e_shnum; ++i) { + Elf_Shdr *s = &sechdrs[i]; + + if ((s->sh_flags & masks[m][0]) != masks[m][0] + || (s->sh_flags & masks[m][1]) + || s->sh_entsize != ~0UL + || strncmp(secstrings + s->sh_name, + ".init", 5) == 0) + continue; + s->sh_entsize = get_offset(&mod->core_size, s); + DEBUGP("\t%s\n", secstrings + s->sh_name); + } + if (m == 0) + mod->core_text_size = mod->core_size; + } + + DEBUGP("Init section allocation order:\n"); + for (m = 0; m < ARRAY_SIZE(masks); ++m) { + for (i = 0; i < hdr->e_shnum; ++i) { + Elf_Shdr *s = &sechdrs[i]; + + if ((s->sh_flags & masks[m][0]) != masks[m][0] + || (s->sh_flags & masks[m][1]) + || s->sh_entsize != ~0UL + || strncmp(secstrings + s->sh_name, + ".init", 5) != 0) + continue; + s->sh_entsize = (get_offset(&mod->init_size, s) + | INIT_OFFSET_MASK); + DEBUGP("\t%s\n", secstrings + s->sh_name); + } + if (m == 0) + mod->init_text_size = mod->init_size; + } +} + +static void set_license(struct module *mod, const char *license) +{ + if (!license) + license = "unspecified"; + + if (!license_is_gpl_compatible(license)) { + if (!test_taint(TAINT_PROPRIETARY_MODULE)) + printk(KERN_WARNING "%s: module license '%s' taints " + "kernel.\n", mod->name, license); + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); + } +} + +/* Parse tag=value strings from .modinfo section */ +static char *next_string(char *string, unsigned long *secsize) +{ + /* Skip non-zero chars */ + while (string[0]) { + string++; + if ((*secsize)-- <= 1) + return NULL; + } + + /* Skip any zero padding. */ + while (!string[0]) { + string++; + if ((*secsize)-- <= 1) + return NULL; + } + return string; +} + +static char *get_modinfo(Elf_Shdr *sechdrs, + unsigned int info, + const char *tag) +{ + char *p; + unsigned int taglen = strlen(tag); + unsigned long size = sechdrs[info].sh_size; + + for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) { + if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') + return p + taglen + 1; + } + return NULL; +} + +static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, + unsigned int infoindex) +{ + struct module_attribute *attr; + int i; + + for (i = 0; (attr = modinfo_attrs[i]); i++) { + if (attr->setup) + attr->setup(mod, + get_modinfo(sechdrs, + infoindex, + attr->attr.name)); + } +} + +#ifdef CONFIG_KALLSYMS + +/* lookup symbol in given range of kernel_symbols */ +static const struct kernel_symbol *lookup_symbol(const char *name, + const struct kernel_symbol *start, + const struct kernel_symbol *stop) +{ + const struct kernel_symbol *ks = start; + for (; ks < stop; ks++) + if (strcmp(ks->name, name) == 0) + return ks; + return NULL; +} + +static int is_exported(const char *name, const struct module *mod) +{ + if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab)) + return 1; + else + if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms)) + return 1; + else + return 0; +} + +/* As per nm */ +static char elf_type(const Elf_Sym *sym, + Elf_Shdr *sechdrs, + const char *secstrings, + struct module *mod) +{ + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { + if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) + return 'v'; + else + return 'w'; + } + if (sym->st_shndx == SHN_UNDEF) + return 'U'; + if (sym->st_shndx == SHN_ABS) + return 'a'; + if (sym->st_shndx >= SHN_LORESERVE) + return '?'; + if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) + return 't'; + if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC + && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { + if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) + return 'r'; + else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) + return 'g'; + else + return 'd'; + } + if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { + if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) + return 's'; + else + return 'b'; + } + if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name, + ".debug", strlen(".debug")) == 0) + return 'n'; + return '?'; +} + +static void add_kallsyms(struct module *mod, + Elf_Shdr *sechdrs, + unsigned int symindex, + unsigned int strindex, + const char *secstrings) +{ + unsigned int i; + + mod->symtab = (void *)sechdrs[symindex].sh_addr; + mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym); + mod->strtab = (void *)sechdrs[strindex].sh_addr; + + /* Set types up while we still have access to sections. */ + for (i = 0; i < mod->num_symtab; i++) + mod->symtab[i].st_info + = elf_type(&mod->symtab[i], sechdrs, secstrings, mod); +} +#else +static inline void add_kallsyms(struct module *mod, + Elf_Shdr *sechdrs, + unsigned int symindex, + unsigned int strindex, + const char *secstrings) +{ +} +#endif /* CONFIG_KALLSYMS */ + +static void dynamic_printk_setup(struct mod_debug *debug, unsigned int num) +{ +#ifdef CONFIG_DYNAMIC_PRINTK_DEBUG + unsigned int i; + + for (i = 0; i < num; i++) { + register_dynamic_debug_module(debug[i].modname, + debug[i].type, + debug[i].logical_modname, + debug[i].flag_names, + debug[i].hash, debug[i].hash2); + } +#endif /* CONFIG_DYNAMIC_PRINTK_DEBUG */ +} + +static void *module_alloc_update_bounds(unsigned long size) +{ + void *ret = module_alloc(size); + + if (ret) { + /* Update module bounds. */ + if ((unsigned long)ret < module_addr_min) + module_addr_min = (unsigned long)ret; + if ((unsigned long)ret + size > module_addr_max) + module_addr_max = (unsigned long)ret + size; + } + return ret; +} + +/* Allocate and load the module: note that size of section 0 is always + zero, and we rely on this for optional sections. */ +static noinline struct module *load_module(void __user *umod, + unsigned long len, + const char __user *uargs) +{ + Elf_Ehdr *hdr; + Elf_Shdr *sechdrs; + char *secstrings, *args, *modmagic, *strtab = NULL; + char *staging; + unsigned int i; + unsigned int symindex = 0; + unsigned int strindex = 0; + unsigned int modindex, versindex, infoindex, pcpuindex; + unsigned int unwindex = 0; + unsigned int num_kp, num_mcount; + struct kernel_param *kp; + struct module *mod; + long err = 0; + void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ + unsigned long *mseg; + mm_segment_t old_fs; + + DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", + umod, len, uargs); + if (len < sizeof(*hdr)) + return ERR_PTR(-ENOEXEC); + + /* Suck in entire file: we'll want most of it. */ + /* vmalloc barfs on "unusual" numbers. Check here */ + if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL) + return ERR_PTR(-ENOMEM); + if (copy_from_user(hdr, umod, len) != 0) { + err = -EFAULT; + goto free_hdr; + } + + /* Sanity checks against insmoding binaries or wrong arch, + weird elf version */ + if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 + || hdr->e_type != ET_REL + || !elf_check_arch(hdr) + || hdr->e_shentsize != sizeof(*sechdrs)) { + err = -ENOEXEC; + goto free_hdr; + } + + if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) + goto truncated; + + /* Convenience variables */ + sechdrs = (void *)hdr + hdr->e_shoff; + secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + sechdrs[0].sh_addr = 0; + + for (i = 1; i < hdr->e_shnum; i++) { + if (sechdrs[i].sh_type != SHT_NOBITS + && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) + goto truncated; + + /* Mark all sections sh_addr with their address in the + temporary image. */ + sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset; + + /* Internal symbols and strings. */ + if (sechdrs[i].sh_type == SHT_SYMTAB) { + symindex = i; + strindex = sechdrs[i].sh_link; + strtab = (char *)hdr + sechdrs[strindex].sh_offset; + } +#ifndef CONFIG_MODULE_UNLOAD + /* Don't load .exit sections */ + if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0) + sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC; +#endif + } + + modindex = find_sec(hdr, sechdrs, secstrings, + ".gnu.linkonce.this_module"); + if (!modindex) { + printk(KERN_WARNING "No module found in object\n"); + err = -ENOEXEC; + goto free_hdr; + } + /* This is temporary: point mod into copy of data. */ + mod = (void *)sechdrs[modindex].sh_addr; + + if (symindex == 0) { + printk(KERN_WARNING "%s: module has no symbols (stripped?)\n", + mod->name); + err = -ENOEXEC; + goto free_hdr; + } + + versindex = find_sec(hdr, sechdrs, secstrings, "__versions"); + infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo"); + pcpuindex = find_pcpusec(hdr, sechdrs, secstrings); +#ifdef ARCH_UNWIND_SECTION_NAME + unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME); +#endif + + /* Don't keep modinfo and version sections. */ + sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; + sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC; +#ifdef CONFIG_KALLSYMS + /* Keep symbol and string tables for decoding later. */ + sechdrs[symindex].sh_flags |= SHF_ALLOC; + sechdrs[strindex].sh_flags |= SHF_ALLOC; +#endif + if (unwindex) + sechdrs[unwindex].sh_flags |= SHF_ALLOC; + + /* Check module struct version now, before we try to use module. */ + if (!check_modstruct_version(sechdrs, versindex, mod)) { + err = -ENOEXEC; + goto free_hdr; + } + + modmagic = get_modinfo(sechdrs, infoindex, "vermagic"); + /* This is allowed: modprobe --force will invalidate it. */ + if (!modmagic) { + err = try_to_force_load(mod, "magic"); + if (err) + goto free_hdr; + } else if (!same_magic(modmagic, vermagic, versindex)) { + printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", + mod->name, modmagic, vermagic); + err = -ENOEXEC; + goto free_hdr; + } + + staging = get_modinfo(sechdrs, infoindex, "staging"); + if (staging) { + add_taint_module(mod, TAINT_CRAP); + printk(KERN_WARNING "%s: module is from the staging directory," + " the quality is unknown, you have been warned.\n", + mod->name); + } + + /* Now copy in args */ + args = strndup_user(uargs, ~0UL >> 1); + if (IS_ERR(args)) { + err = PTR_ERR(args); + goto free_hdr; + } + + if (find_module(mod->name)) { + err = -EEXIST; + goto free_mod; + } + + mod->state = MODULE_STATE_COMING; + + /* Allow arches to frob section contents and sizes. */ + err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod); + if (err < 0) + goto free_mod; + + if (pcpuindex) { + /* We have a special allocation for this section. */ + percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size, + sechdrs[pcpuindex].sh_addralign, + mod->name); + if (!percpu) { + err = -ENOMEM; + goto free_mod; + } + sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC; + mod->percpu = percpu; + } + + /* Determine total sizes, and put offsets in sh_entsize. For now + this is done generically; there doesn't appear to be any + special cases for the architectures. */ + layout_sections(mod, hdr, sechdrs, secstrings); + + /* Do the allocs. */ + ptr = module_alloc_update_bounds(mod->core_size); + if (!ptr) { + err = -ENOMEM; + goto free_percpu; + } + memset(ptr, 0, mod->core_size); + mod->module_core = ptr; + + ptr = module_alloc_update_bounds(mod->init_size); + if (!ptr && mod->init_size) { + err = -ENOMEM; + goto free_core; + } + memset(ptr, 0, mod->init_size); + mod->module_init = ptr; + + /* Transfer each section which specifies SHF_ALLOC */ + DEBUGP("final section addresses:\n"); + for (i = 0; i < hdr->e_shnum; i++) { + void *dest; + + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + + if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK) + dest = mod->module_init + + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK); + else + dest = mod->module_core + sechdrs[i].sh_entsize; + + if (sechdrs[i].sh_type != SHT_NOBITS) + memcpy(dest, (void *)sechdrs[i].sh_addr, + sechdrs[i].sh_size); + /* Update sh_addr to point to copy in image. */ + sechdrs[i].sh_addr = (unsigned long)dest; + DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name); + } + /* Module has been moved. */ + mod = (void *)sechdrs[modindex].sh_addr; + + /* Now we've moved module, initialize linked lists, etc. */ + module_unload_init(mod); + + /* add kobject, so we can reference it. */ + err = mod_sysfs_init(mod); + if (err) + goto free_unload; + + /* Set up license info based on the info section */ + set_license(mod, get_modinfo(sechdrs, infoindex, "license")); + + /* + * ndiswrapper is under GPL by itself, but loads proprietary modules. + * Don't use add_taint_module(), as it would prevent ndiswrapper from + * using GPL-only symbols it needs. + */ + if (strcmp(mod->name, "ndiswrapper") == 0) + add_taint(TAINT_PROPRIETARY_MODULE); + + /* driverloader was caught wrongly pretending to be under GPL */ + if (strcmp(mod->name, "driverloader") == 0) + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); + + /* Set up MODINFO_ATTR fields */ + setup_modinfo(mod, sechdrs, infoindex); + + /* Fix up syms, so that st_value is a pointer to location. */ + err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex, + mod); + if (err < 0) + goto cleanup; + + /* Now we've got everything in the final locations, we can + * find optional sections. */ + kp = section_objs(hdr, sechdrs, secstrings, "__param", sizeof(*kp), + &num_kp); + mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab", + sizeof(*mod->syms), &mod->num_syms); + mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab"); + mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl", + sizeof(*mod->gpl_syms), + &mod->num_gpl_syms); + mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl"); + mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings, + "__ksymtab_gpl_future", + sizeof(*mod->gpl_future_syms), + &mod->num_gpl_future_syms); + mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings, + "__kcrctab_gpl_future"); + +#ifdef CONFIG_UNUSED_SYMBOLS + mod->unused_syms = section_objs(hdr, sechdrs, secstrings, + "__ksymtab_unused", + sizeof(*mod->unused_syms), + &mod->num_unused_syms); + mod->unused_crcs = section_addr(hdr, sechdrs, secstrings, + "__kcrctab_unused"); + mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings, + "__ksymtab_unused_gpl", + sizeof(*mod->unused_gpl_syms), + &mod->num_unused_gpl_syms); + mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings, + "__kcrctab_unused_gpl"); +#endif + +#ifdef CONFIG_MARKERS + mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers", + sizeof(*mod->markers), &mod->num_markers); +#endif +#ifdef CONFIG_TRACEPOINTS + mod->tracepoints = section_objs(hdr, sechdrs, secstrings, + "__tracepoints", + sizeof(*mod->tracepoints), + &mod->num_tracepoints); +#endif + +#ifdef CONFIG_MODVERSIONS + if ((mod->num_syms && !mod->crcs) + || (mod->num_gpl_syms && !mod->gpl_crcs) + || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) +#ifdef CONFIG_UNUSED_SYMBOLS + || (mod->num_unused_syms && !mod->unused_crcs) + || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) +#endif + ) { + printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name); + err = try_to_force_load(mod, "nocrc"); + if (err) + goto cleanup; + } +#endif + + /* Now do relocations. */ + for (i = 1; i < hdr->e_shnum; i++) { + const char *strtab = (char *)sechdrs[strindex].sh_addr; + unsigned int info = sechdrs[i].sh_info; + + /* Not a valid relocation section? */ + if (info >= hdr->e_shnum) + continue; + + /* Don't bother with non-allocated sections */ + if (!(sechdrs[info].sh_flags & SHF_ALLOC)) + continue; + + if (sechdrs[i].sh_type == SHT_REL) + err = apply_relocate(sechdrs, strtab, symindex, i,mod); + else if (sechdrs[i].sh_type == SHT_RELA) + err = apply_relocate_add(sechdrs, strtab, symindex, i, + mod); + if (err < 0) + goto cleanup; + } + + /* Find duplicate symbols */ + err = verify_export_symbols(mod); + if (err < 0) + goto cleanup; + + /* Set up and sort exception table */ + mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table", + sizeof(*mod->extable), &mod->num_exentries); + sort_extable(mod->extable, mod->extable + mod->num_exentries); + + /* Finally, copy percpu area over. */ + percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr, + sechdrs[pcpuindex].sh_size); + + add_kallsyms(mod, sechdrs, symindex, strindex, secstrings); + + if (!mod->taints) { + struct mod_debug *debug; + unsigned int num_debug; + +#ifdef CONFIG_MARKERS + marker_update_probe_range(mod->markers, + mod->markers + mod->num_markers); +#endif + debug = section_objs(hdr, sechdrs, secstrings, "__verbose", + sizeof(*debug), &num_debug); + dynamic_printk_setup(debug, num_debug); + +#ifdef CONFIG_TRACEPOINTS + tracepoint_update_probe_range(mod->tracepoints, + mod->tracepoints + mod->num_tracepoints); +#endif + } + + /* sechdrs[0].sh_size is always zero */ + mseg = section_objs(hdr, sechdrs, secstrings, "__mcount_loc", + sizeof(*mseg), &num_mcount); + ftrace_init_module(mseg, mseg + num_mcount); + + err = module_finalize(hdr, sechdrs, mod); + if (err < 0) + goto cleanup; + + /* flush the icache in correct context */ + old_fs = get_fs(); + set_fs(KERNEL_DS); + + /* + * Flush the instruction cache, since we've played with text. + * Do it before processing of module parameters, so the module + * can provide parameter accessor functions of its own. + */ + if (mod->module_init) + flush_icache_range((unsigned long)mod->module_init, + (unsigned long)mod->module_init + + mod->init_size); + flush_icache_range((unsigned long)mod->module_core, + (unsigned long)mod->module_core + mod->core_size); + + set_fs(old_fs); + + mod->args = args; + if (section_addr(hdr, sechdrs, secstrings, "__obsparm")) + printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", + mod->name); + + /* Now sew it into the lists so we can get lockdep and oops + * info during argument parsing. Noone should access us, since + * strong_try_module_get() will fail. + * lockdep/oops can run asynchronous, so use the RCU list insertion + * function to insert in a way safe to concurrent readers. + * The mutex protects against concurrent writers. + */ + list_add_rcu(&mod->list, &modules); + + err = parse_args(mod->name, mod->args, kp, num_kp, NULL); + if (err < 0) + goto unlink; + + err = mod_sysfs_setup(mod, kp, num_kp); + if (err < 0) + goto unlink; + add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); + add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs); + + /* Size of section 0 is 0, so this works well if no unwind info. */ + mod->unwind_info = unwind_add_table(mod, + (void *)sechdrs[unwindex].sh_addr, + sechdrs[unwindex].sh_size); + + /* Get rid of temporary copy */ + vfree(hdr); + + /* Done! */ + return mod; + + unlink: + stop_machine(__unlink_module, mod, NULL); + module_arch_cleanup(mod); + cleanup: + kobject_del(&mod->mkobj.kobj); + kobject_put(&mod->mkobj.kobj); + ftrace_release(mod->module_core, mod->core_size); + free_unload: + module_unload_free(mod); + module_free(mod, mod->module_init); + free_core: + module_free(mod, mod->module_core); + free_percpu: + if (percpu) + percpu_modfree(percpu); + free_mod: + kfree(args); + free_hdr: + vfree(hdr); + return ERR_PTR(err); + + truncated: + printk(KERN_ERR "Module len %lu truncated\n", len); + err = -ENOEXEC; + goto free_hdr; +} + +/* This is where the real work happens */ +SYSCALL_DEFINE3(init_module, void __user *, umod, + unsigned long, len, const char __user *, uargs) +{ + struct module *mod; + int ret = 0; + + /* Must have permission */ + if (!capable(CAP_SYS_MODULE)) + return -EPERM; + + /* Only one module load at a time, please */ + if (mutex_lock_interruptible(&module_mutex) != 0) + return -EINTR; + + /* Do all the hard work */ + mod = load_module(umod, len, uargs); + if (IS_ERR(mod)) { + mutex_unlock(&module_mutex); + return PTR_ERR(mod); + } + + /* Drop lock so they can recurse */ + mutex_unlock(&module_mutex); + + blocking_notifier_call_chain(&module_notify_list, + MODULE_STATE_COMING, mod); + + /* Start the module */ + if (mod->init != NULL) + ret = do_one_initcall(mod->init); + if (ret < 0) { + /* Init routine failed: abort. Try to protect us from + buggy refcounters. */ + mod->state = MODULE_STATE_GOING; + synchronize_sched(); + module_put(mod); + blocking_notifier_call_chain(&module_notify_list, + MODULE_STATE_GOING, mod); + mutex_lock(&module_mutex); + free_module(mod); + mutex_unlock(&module_mutex); + wake_up(&module_wq); + return ret; + } + if (ret > 0) { + printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, " + "it should follow 0/-E convention\n" + KERN_WARNING "%s: loading module anyway...\n", + __func__, mod->name, ret, + __func__); + dump_stack(); + } + + /* Now it's a first class citizen! Wake up anyone waiting for it. */ + mod->state = MODULE_STATE_LIVE; + wake_up(&module_wq); + + mutex_lock(&module_mutex); + /* Drop initial reference. */ + module_put(mod); + unwind_remove_table(mod->unwind_info, 1); + module_free(mod, mod->module_init); + mod->module_init = NULL; + mod->init_size = 0; + mod->init_text_size = 0; + mutex_unlock(&module_mutex); + + return 0; +} + +static inline int within(unsigned long addr, void *start, unsigned long size) +{ + return ((void *)addr >= start && (void *)addr < start + size); +} + +#ifdef CONFIG_KALLSYMS +/* + * This ignores the intensely annoying "mapping symbols" found + * in ARM ELF files: $a, $t and $d. + */ +static inline int is_arm_mapping_symbol(const char *str) +{ + return str[0] == '$' && strchr("atd", str[1]) + && (str[2] == '\0' || str[2] == '.'); +} + +static const char *get_ksymbol(struct module *mod, + unsigned long addr, + unsigned long *size, + unsigned long *offset) +{ + unsigned int i, best = 0; + unsigned long nextval; + + /* At worse, next value is at end of module */ + if (within(addr, mod->module_init, mod->init_size)) + nextval = (unsigned long)mod->module_init+mod->init_text_size; + else + nextval = (unsigned long)mod->module_core+mod->core_text_size; + + /* Scan for closest preceeding symbol, and next symbol. (ELF + starts real symbols at 1). */ + for (i = 1; i < mod->num_symtab; i++) { + if (mod->symtab[i].st_shndx == SHN_UNDEF) + continue; + + /* We ignore unnamed symbols: they're uninformative + * and inserted at a whim. */ + if (mod->symtab[i].st_value <= addr + && mod->symtab[i].st_value > mod->symtab[best].st_value + && *(mod->strtab + mod->symtab[i].st_name) != '\0' + && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) + best = i; + if (mod->symtab[i].st_value > addr + && mod->symtab[i].st_value < nextval + && *(mod->strtab + mod->symtab[i].st_name) != '\0' + && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) + nextval = mod->symtab[i].st_value; + } + + if (!best) + return NULL; + + if (size) + *size = nextval - mod->symtab[best].st_value; + if (offset) + *offset = addr - mod->symtab[best].st_value; + return mod->strtab + mod->symtab[best].st_name; +} + +/* For kallsyms to ask for address resolution. NULL means not found. Careful + * not to lock to avoid deadlock on oopses, simply disable preemption. */ +const char *module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + char *namebuf) +{ + struct module *mod; + const char *ret = NULL; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (within(addr, mod->module_init, mod->init_size) + || within(addr, mod->module_core, mod->core_size)) { + if (modname) + *modname = mod->name; + ret = get_ksymbol(mod, addr, size, offset); + break; + } + } + /* Make a copy in here where it's safe */ + if (ret) { + strncpy(namebuf, ret, KSYM_NAME_LEN - 1); + ret = namebuf; + } + preempt_enable(); + return ret; +} + +int lookup_module_symbol_name(unsigned long addr, char *symname) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (within(addr, mod->module_init, mod->init_size) || + within(addr, mod->module_core, mod->core_size)) { + const char *sym; + + sym = get_ksymbol(mod, addr, NULL, NULL); + if (!sym) + goto out; + strlcpy(symname, sym, KSYM_NAME_LEN); + preempt_enable(); + return 0; + } + } +out: + preempt_enable(); + return -ERANGE; +} + +int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, + unsigned long *offset, char *modname, char *name) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (within(addr, mod->module_init, mod->init_size) || + within(addr, mod->module_core, mod->core_size)) { + const char *sym; + + sym = get_ksymbol(mod, addr, size, offset); + if (!sym) + goto out; + if (modname) + strlcpy(modname, mod->name, MODULE_NAME_LEN); + if (name) + strlcpy(name, sym, KSYM_NAME_LEN); + preempt_enable(); + return 0; + } + } +out: + preempt_enable(); + return -ERANGE; +} + +int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, + char *name, char *module_name, int *exported) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (symnum < mod->num_symtab) { + *value = mod->symtab[symnum].st_value; + *type = mod->symtab[symnum].st_info; + strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, + KSYM_NAME_LEN); + strlcpy(module_name, mod->name, MODULE_NAME_LEN); + *exported = is_exported(name, mod); + preempt_enable(); + return 0; + } + symnum -= mod->num_symtab; + } + preempt_enable(); + return -ERANGE; +} + +static unsigned long mod_find_symname(struct module *mod, const char *name) +{ + unsigned int i; + + for (i = 0; i < mod->num_symtab; i++) + if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 && + mod->symtab[i].st_info != 'U') + return mod->symtab[i].st_value; + return 0; +} + +/* Look for this name: can be of form module:name. */ +unsigned long module_kallsyms_lookup_name(const char *name) +{ + struct module *mod; + char *colon; + unsigned long ret = 0; + + /* Don't lock: we're in enough trouble already. */ + preempt_disable(); + if ((colon = strchr(name, ':')) != NULL) { + *colon = '\0'; + if ((mod = find_module(name)) != NULL) + ret = mod_find_symname(mod, colon+1); + *colon = ':'; + } else { + list_for_each_entry_rcu(mod, &modules, list) + if ((ret = mod_find_symname(mod, name)) != 0) + break; + } + preempt_enable(); + return ret; +} +#endif /* CONFIG_KALLSYMS */ + +static char *module_flags(struct module *mod, char *buf) +{ + int bx = 0; + + if (mod->taints || + mod->state == MODULE_STATE_GOING || + mod->state == MODULE_STATE_COMING) { + buf[bx++] = '('; + if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) + buf[bx++] = 'P'; + if (mod->taints & (1 << TAINT_FORCED_MODULE)) + buf[bx++] = 'F'; + if (mod->taints & (1 << TAINT_CRAP)) + buf[bx++] = 'C'; + /* + * TAINT_FORCED_RMMOD: could be added. + * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't + * apply to modules. + */ + + /* Show a - for module-is-being-unloaded */ + if (mod->state == MODULE_STATE_GOING) + buf[bx++] = '-'; + /* Show a + for module-is-being-loaded */ + if (mod->state == MODULE_STATE_COMING) + buf[bx++] = '+'; + buf[bx++] = ')'; + } + buf[bx] = '\0'; + + return buf; +} + +#ifdef CONFIG_PROC_FS +/* Called by the /proc file system to return a list of modules. */ +static void *m_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&module_mutex); + return seq_list_start(&modules, *pos); +} + +static void *m_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &modules, pos); +} + +static void m_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&module_mutex); +} + +static int m_show(struct seq_file *m, void *p) +{ + struct module *mod = list_entry(p, struct module, list); + char buf[8]; + + seq_printf(m, "%s %u", + mod->name, mod->init_size + mod->core_size); + print_unload_info(m, mod); + + /* Informative for users. */ + seq_printf(m, " %s", + mod->state == MODULE_STATE_GOING ? "Unloading": + mod->state == MODULE_STATE_COMING ? "Loading": + "Live"); + /* Used by oprofile and other similar tools. */ + seq_printf(m, " 0x%p", mod->module_core); + + /* Taints info */ + if (mod->taints) + seq_printf(m, " %s", module_flags(mod, buf)); + + seq_printf(m, "\n"); + return 0; +} + +/* Format: modulename size refcount deps address + + Where refcount is a number or -, and deps is a comma-separated list + of depends or -. +*/ +static const struct seq_operations modules_op = { + .start = m_start, + .next = m_next, + .stop = m_stop, + .show = m_show +}; + +static int modules_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &modules_op); +} + +static const struct file_operations proc_modules_operations = { + .open = modules_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init proc_modules_init(void) +{ + proc_create("modules", 0, NULL, &proc_modules_operations); + return 0; +} +module_init(proc_modules_init); +#endif + +/* Given an address, look for it in the module exception tables. */ +const struct exception_table_entry *search_module_extables(unsigned long addr) +{ + const struct exception_table_entry *e = NULL; + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (mod->num_exentries == 0) + continue; + + e = search_extable(mod->extable, + mod->extable + mod->num_exentries - 1, + addr); + if (e) + break; + } + preempt_enable(); + + /* Now, if we found one, we are running inside it now, hence + we cannot unload the module, hence no refcnt needed. */ + return e; +} + +/* + * Is this a valid module address? + */ +int is_module_address(unsigned long addr) +{ + struct module *mod; + + preempt_disable(); + + list_for_each_entry_rcu(mod, &modules, list) { + if (within(addr, mod->module_core, mod->core_size)) { + preempt_enable(); + return 1; + } + } + + preempt_enable(); + + return 0; +} + + +/* Is this a valid kernel address? */ +struct module *__module_text_address(unsigned long addr) +{ + struct module *mod; + + if (addr < module_addr_min || addr > module_addr_max) + return NULL; + + list_for_each_entry_rcu(mod, &modules, list) + if (within(addr, mod->module_init, mod->init_text_size) + || within(addr, mod->module_core, mod->core_text_size)) + return mod; + return NULL; +} + +struct module *module_text_address(unsigned long addr) +{ + struct module *mod; + + preempt_disable(); + mod = __module_text_address(addr); + preempt_enable(); + + return mod; +} + +/* Don't grab lock, we're oopsing. */ +void print_modules(void) +{ + struct module *mod; + char buf[8]; + + printk("Modules linked in:"); + /* Most callers should already have preempt disabled, but make sure */ + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) + printk(" %s%s", mod->name, module_flags(mod, buf)); + preempt_enable(); + if (last_unloaded_module[0]) + printk(" [last unloaded: %s]", last_unloaded_module); + printk("\n"); +} + +#ifdef CONFIG_MODVERSIONS +/* Generate the signature for struct module here, too, for modversions. */ +void struct_module(struct module *mod) { return; } +EXPORT_SYMBOL(struct_module); +#endif + +#ifdef CONFIG_MARKERS +void module_update_markers(void) +{ + struct module *mod; + + mutex_lock(&module_mutex); + list_for_each_entry(mod, &modules, list) + if (!mod->taints) + marker_update_probe_range(mod->markers, + mod->markers + mod->num_markers); + mutex_unlock(&module_mutex); +} +#endif + +#ifdef CONFIG_TRACEPOINTS +void module_update_tracepoints(void) +{ + struct module *mod; + + mutex_lock(&module_mutex); + list_for_each_entry(mod, &modules, list) + if (!mod->taints) + tracepoint_update_probe_range(mod->tracepoints, + mod->tracepoints + mod->num_tracepoints); + mutex_unlock(&module_mutex); +} + +/* + * Returns 0 if current not found. + * Returns 1 if current found. + */ +int module_get_iter_tracepoints(struct tracepoint_iter *iter) +{ + struct module *iter_mod; + int found = 0; + + mutex_lock(&module_mutex); + list_for_each_entry(iter_mod, &modules, list) { + if (!iter_mod->taints) { + /* + * Sorted module list + */ + if (iter_mod < iter->module) + continue; + else if (iter_mod > iter->module) + iter->tracepoint = NULL; + found = tracepoint_get_iter_range(&iter->tracepoint, + iter_mod->tracepoints, + iter_mod->tracepoints + + iter_mod->num_tracepoints); + if (found) { + iter->module = iter_mod; + break; + } + } + } + mutex_unlock(&module_mutex); + return found; +} +#endif |
