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-rw-r--r--kernel/module.c2108
1 files changed, 2108 insertions, 0 deletions
diff --git a/kernel/module.c b/kernel/module.c
new file mode 100644
index 000000000000..2dbfa0773faf
--- /dev/null
+++ b/kernel/module.c
@@ -0,0 +1,2108 @@
+/* Rewritten by Rusty Russell, on the backs of many others...
+ 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/config.h>
+#include <linux/module.h>
+#include <linux/moduleloader.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/elf.h>
+#include <linux/seq_file.h>
+#include <linux/syscalls.h>
+#include <linux/fcntl.h>
+#include <linux/rcupdate.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/stop_machine.h>
+#include <linux/device.h>
+#include <asm/uaccess.h>
+#include <asm/semaphore.h>
+#include <asm/cacheflush.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))
+
+/* Protects module list */
+static DEFINE_SPINLOCK(modlist_lock);
+
+/* List of modules, protected by module_mutex AND modlist_lock */
+static DECLARE_MUTEX(module_mutex);
+static LIST_HEAD(modules);
+
+static DECLARE_MUTEX(notify_mutex);
+static struct notifier_block * module_notify_list;
+
+int register_module_notifier(struct notifier_block * nb)
+{
+ int err;
+ down(&notify_mutex);
+ err = notifier_chain_register(&module_notify_list, nb);
+ up(&notify_mutex);
+ return err;
+}
+EXPORT_SYMBOL(register_module_notifier);
+
+int unregister_module_notifier(struct notifier_block * nb)
+{
+ int err;
+ down(&notify_mutex);
+ err = notifier_chain_unregister(&module_notify_list, nb);
+ up(&notify_mutex);
+ return err;
+}
+EXPORT_SYMBOL(unregister_module_notifier);
+
+/* We require a truly strong try_module_get() */
+static inline int strong_try_module_get(struct module *mod)
+{
+ if (mod && mod->state == MODULE_STATE_COMING)
+ return 0;
+ return try_module_get(mod);
+}
+
+/* A thread that wants to hold a reference to a module only while it
+ * is running can call ths 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;
+}
+
+/* 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 unsigned long __start___kcrctab[];
+extern const unsigned long __start___kcrctab_gpl[];
+
+#ifndef CONFIG_MODVERSIONS
+#define symversion(base, idx) NULL
+#else
+#define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL)
+#endif
+
+/* Find a symbol, return value, crc and module which owns it */
+static unsigned long __find_symbol(const char *name,
+ struct module **owner,
+ const unsigned long **crc,
+ int gplok)
+{
+ struct module *mod;
+ unsigned int i;
+
+ /* Core kernel first. */
+ *owner = NULL;
+ for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) {
+ if (strcmp(__start___ksymtab[i].name, name) == 0) {
+ *crc = symversion(__start___kcrctab, i);
+ return __start___ksymtab[i].value;
+ }
+ }
+ if (gplok) {
+ for (i = 0; __start___ksymtab_gpl+i<__stop___ksymtab_gpl; i++)
+ if (strcmp(__start___ksymtab_gpl[i].name, name) == 0) {
+ *crc = symversion(__start___kcrctab_gpl, i);
+ return __start___ksymtab_gpl[i].value;
+ }
+ }
+
+ /* Now try modules. */
+ list_for_each_entry(mod, &modules, list) {
+ *owner = mod;
+ for (i = 0; i < mod->num_syms; i++)
+ if (strcmp(mod->syms[i].name, name) == 0) {
+ *crc = symversion(mod->crcs, i);
+ return mod->syms[i].value;
+ }
+
+ if (gplok) {
+ for (i = 0; i < mod->num_gpl_syms; i++) {
+ if (strcmp(mod->gpl_syms[i].name, name) == 0) {
+ *crc = symversion(mod->gpl_crcs, i);
+ return mod->gpl_syms[i].value;
+ }
+ }
+ }
+ }
+ DEBUGP("Failed to find symbol %s\n", name);
+ return 0;
+}
+
+/* Find a symbol in this elf symbol table */
+static unsigned long find_local_symbol(Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ const char *strtab,
+ const char *name)
+{
+ unsigned int i;
+ Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
+
+ /* Search (defined) internal symbols first. */
+ for (i = 1; i < sechdrs[symindex].sh_size/sizeof(*sym); i++) {
+ if (sym[i].st_shndx != SHN_UNDEF
+ && strcmp(name, strtab + sym[i].st_name) == 0)
+ return sym[i].st_value;
+ }
+ return 0;
+}
+
+/* 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 = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
+ GFP_KERNEL);
+ if (!new)
+ return 0;
+
+ memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
+ pcpu_num_allocated *= 2;
+ kfree(pcpu_size);
+ 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;
+}
+
+/* Created by linker magic */
+extern char __per_cpu_start[], __per_cpu_end[];
+
+static void *percpu_modalloc(unsigned long size, unsigned long align)
+{
+ unsigned long extra;
+ unsigned int i;
+ void *ptr;
+
+ BUG_ON(align > SMP_CACHE_BYTES);
+
+ 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 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] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
+ /* 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)
+{
+ 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 */
+
+#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[_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;
+ if (b == NULL || already_uses(a, b)) return 1;
+
+ if (!strong_try_module_get(b))
+ 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);
+ 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);
+ /* There can be at most one match. */
+ break;
+ }
+ }
+ }
+}
+
+#ifdef CONFIG_MODULE_FORCE_UNLOAD
+static inline int try_force(unsigned int flags)
+{
+ int ret = (flags & O_TRUNC);
+ if (ret)
+ tainted |= TAINT_FORCED_MODULE;
+ return ret;
+}
+#else
+static inline int try_force(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 are told to block. */
+ if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
+ if (!(*sref->forced = try_force(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)
+{
+ struct stopref sref = { mod, flags, forced };
+
+ return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
+}
+
+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, drop the semaphore first */
+ up(&module_mutex);
+ for (;;) {
+ DEBUGP("Looking at refcount...\n");
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (module_refcount(mod) == 0)
+ break;
+ schedule();
+ }
+ current->state = TASK_RUNNING;
+ down(&module_mutex);
+}
+
+asmlinkage long
+sys_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 (down_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 != NULL && mod->exit == NULL)
+ || mod->unsafe) {
+ forced = try_force(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);
+
+ /* Final destruction now noone is using it. */
+ if (mod->exit != NULL) {
+ up(&module_mutex);
+ mod->exit();
+ down(&module_mutex);
+ }
+ free_module(mod);
+
+ out:
+ up(&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->unsafe) {
+ printed_something = 1;
+ seq_printf(m, "[unsafe],");
+ }
+
+ 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;
+ unsigned long flags;
+ const unsigned long *crc;
+
+ spin_lock_irqsave(&modlist_lock, flags);
+ if (!__find_symbol(symbol, &owner, &crc, 1))
+ BUG();
+ module_put(owner);
+ spin_unlock_irqrestore(&modlist_lock, flags);
+}
+EXPORT_SYMBOL(__symbol_put);
+
+void symbol_put_addr(void *addr)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&modlist_lock, flags);
+ if (!kernel_text_address((unsigned long)addr))
+ BUG();
+
+ module_put(module_text_address((unsigned long)addr));
+ spin_unlock_irqrestore(&modlist_lock, flags);
+}
+EXPORT_SYMBOL_GPL(symbol_put_addr);
+
+static ssize_t show_refcnt(struct module_attribute *mattr,
+ struct module *mod, char *buffer)
+{
+ /* sysfs holds a reference */
+ return sprintf(buffer, "%u\n", module_refcount(mod)-1);
+}
+
+static struct module_attribute refcnt = {
+ .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
+ .show = show_refcnt,
+};
+
+#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);
+}
+
+static inline void module_unload_init(struct module *mod)
+{
+}
+#endif /* CONFIG_MODULE_UNLOAD */
+
+#ifdef CONFIG_OBSOLETE_MODPARM
+/* Bounds checking done below */
+static int obsparm_copy_string(const char *val, struct kernel_param *kp)
+{
+ strcpy(kp->arg, val);
+ return 0;
+}
+
+int set_obsolete(const char *val, struct kernel_param *kp)
+{
+ unsigned int min, max;
+ unsigned int size, maxsize;
+ int dummy;
+ char *endp;
+ const char *p;
+ struct obsolete_modparm *obsparm = kp->arg;
+
+ if (!val) {
+ printk(KERN_ERR "Parameter %s needs an argument\n", kp->name);
+ return -EINVAL;
+ }
+
+ /* type is: [min[-max]]{b,h,i,l,s} */
+ p = obsparm->type;
+ min = simple_strtol(p, &endp, 10);
+ if (endp == obsparm->type)
+ min = max = 1;
+ else if (*endp == '-') {
+ p = endp+1;
+ max = simple_strtol(p, &endp, 10);
+ } else
+ max = min;
+ switch (*endp) {
+ case 'b':
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ 1, param_set_byte, &dummy);
+ case 'h':
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ sizeof(short), param_set_short, &dummy);
+ case 'i':
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ sizeof(int), param_set_int, &dummy);
+ case 'l':
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ sizeof(long), param_set_long, &dummy);
+ case 's':
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ sizeof(char *), param_set_charp, &dummy);
+
+ case 'c':
+ /* Undocumented: 1-5c50 means 1-5 strings of up to 49 chars,
+ and the decl is "char xxx[5][50];" */
+ p = endp+1;
+ maxsize = simple_strtol(p, &endp, 10);
+ /* We check lengths here (yes, this is a hack). */
+ p = val;
+ while (p[size = strcspn(p, ",")]) {
+ if (size >= maxsize)
+ goto oversize;
+ p += size+1;
+ }
+ if (size >= maxsize)
+ goto oversize;
+ return param_array(kp->name, val, min, max, obsparm->addr,
+ maxsize, obsparm_copy_string, &dummy);
+ }
+ printk(KERN_ERR "Unknown obsolete parameter type %s\n", obsparm->type);
+ return -EINVAL;
+ oversize:
+ printk(KERN_ERR
+ "Parameter %s doesn't fit in %u chars.\n", kp->name, maxsize);
+ return -EINVAL;
+}
+
+static int obsolete_params(const char *name,
+ char *args,
+ struct obsolete_modparm obsparm[],
+ unsigned int num,
+ Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ const char *strtab)
+{
+ struct kernel_param *kp;
+ unsigned int i;
+ int ret;
+
+ kp = kmalloc(sizeof(kp[0]) * num, GFP_KERNEL);
+ if (!kp)
+ return -ENOMEM;
+
+ for (i = 0; i < num; i++) {
+ char sym_name[128 + sizeof(MODULE_SYMBOL_PREFIX)];
+
+ snprintf(sym_name, sizeof(sym_name), "%s%s",
+ MODULE_SYMBOL_PREFIX, obsparm[i].name);
+
+ kp[i].name = obsparm[i].name;
+ kp[i].perm = 000;
+ kp[i].set = set_obsolete;
+ kp[i].get = NULL;
+ obsparm[i].addr
+ = (void *)find_local_symbol(sechdrs, symindex, strtab,
+ sym_name);
+ if (!obsparm[i].addr) {
+ printk("%s: falsely claims to have parameter %s\n",
+ name, obsparm[i].name);
+ ret = -EINVAL;
+ goto out;
+ }
+ kp[i].arg = &obsparm[i];
+ }
+
+ ret = parse_args(name, args, kp, num, NULL);
+ out:
+ kfree(kp);
+ return ret;
+}
+#else
+static int obsolete_params(const char *name,
+ char *args,
+ struct obsolete_modparm obsparm[],
+ unsigned int num,
+ Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ const char *strtab)
+{
+ if (num != 0)
+ printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
+ name);
+ return 0;
+}
+#endif /* CONFIG_OBSOLETE_MODPARM */
+
+static const char vermagic[] = VERMAGIC_STRING;
+
+#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;
+
+ 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;
+ printk("%s: disagrees about version of symbol %s\n",
+ mod->name, symname);
+ DEBUGP("Found checksum %lX vs module %lX\n",
+ *crc, versions[i].crc);
+ return 0;
+ }
+ /* Not in module's version table. OK, but that taints the kernel. */
+ if (!(tainted & TAINT_FORCED_MODULE)) {
+ printk("%s: no version for \"%s\" found: kernel tainted.\n",
+ mod->name, symname);
+ tainted |= TAINT_FORCED_MODULE;
+ }
+ return 1;
+}
+
+static inline int check_modstruct_version(Elf_Shdr *sechdrs,
+ unsigned int versindex,
+ struct module *mod)
+{
+ const unsigned long *crc;
+ struct module *owner;
+
+ if (!__find_symbol("struct_module", &owner, &crc, 1))
+ BUG();
+ return check_version(sechdrs, versindex, "struct_module", mod,
+ crc);
+}
+
+/* First part is kernel version, which we ignore. */
+static inline int same_magic(const char *amagic, const char *bmagic)
+{
+ 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)
+{
+ 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;
+
+ spin_lock_irq(&modlist_lock);
+ ret = __find_symbol(name, &owner, &crc, mod->license_gplok);
+ if (ret) {
+ /* use_module can fail due to OOM, or module unloading */
+ if (!check_version(sechdrs, versindex, name, mod, crc) ||
+ !use_module(mod, owner))
+ ret = 0;
+ }
+ spin_unlock_irq(&modlist_lock);
+ return ret;
+}
+
+
+/*
+ * /sys/module/foo/sections stuff
+ * J. Corbet <corbet@lwn.net>
+ */
+#ifdef CONFIG_KALLSYMS
+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 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]);
+ if (! (sect_attrs = kmalloc(size[0] + size[1], GFP_KERNEL)))
+ return;
+
+ /* Setup section attributes. */
+ sect_attrs->grp.name = "sections";
+ sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
+
+ sattr = &sect_attrs->attrs[0];
+ gattr = &sect_attrs->grp.attrs[0];
+ for (i = 0; i < nsect; i++) {
+ if (! (sechdrs[i].sh_flags & SHF_ALLOC))
+ continue;
+ sattr->address = sechdrs[i].sh_addr;
+ strlcpy(sattr->name, secstrings + sechdrs[i].sh_name,
+ MODULE_SECT_NAME_LEN);
+ sattr->mattr.show = module_sect_show;
+ sattr->mattr.store = NULL;
+ sattr->mattr.attr.name = sattr->name;
+ sattr->mattr.attr.owner = mod;
+ sattr->mattr.attr.mode = S_IRUGO;
+ *(gattr++) = &(sattr++)->mattr.attr;
+ }
+ *gattr = NULL;
+
+ if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
+ goto out;
+
+ mod->sect_attrs = sect_attrs;
+ return;
+ out:
+ kfree(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. */
+ kfree(mod->sect_attrs);
+ mod->sect_attrs = NULL;
+ }
+}
+
+
+#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)
+{
+}
+#endif /* CONFIG_KALLSYMS */
+
+
+#ifdef CONFIG_MODULE_UNLOAD
+static inline int module_add_refcnt_attr(struct module *mod)
+{
+ return sysfs_create_file(&mod->mkobj.kobj, &refcnt.attr);
+}
+static void module_remove_refcnt_attr(struct module *mod)
+{
+ return sysfs_remove_file(&mod->mkobj.kobj, &refcnt.attr);
+}
+#else
+static inline int module_add_refcnt_attr(struct module *mod)
+{
+ return 0;
+}
+static void module_remove_refcnt_attr(struct module *mod)
+{
+}
+#endif
+
+
+static int mod_sysfs_setup(struct module *mod,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ int err;
+
+ memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
+ err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
+ if (err)
+ goto out;
+ kobj_set_kset_s(&mod->mkobj, module_subsys);
+ mod->mkobj.mod = mod;
+ err = kobject_register(&mod->mkobj.kobj);
+ if (err)
+ goto out;
+
+ err = module_add_refcnt_attr(mod);
+ if (err)
+ goto out_unreg;
+
+ err = module_param_sysfs_setup(mod, kparam, num_params);
+ if (err)
+ goto out_unreg;
+
+ return 0;
+
+out_unreg:
+ kobject_unregister(&mod->mkobj.kobj);
+out:
+ return err;
+}
+
+static void mod_kobject_remove(struct module *mod)
+{
+ module_remove_refcnt_attr(mod);
+ module_param_sysfs_remove(mod);
+
+ kobject_unregister(&mod->mkobj.kobj);
+}
+
+/*
+ * 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_run(__unlink_module, mod, NR_CPUS);
+ remove_sect_attrs(mod);
+ mod_kobject_remove(mod);
+
+ /* Arch-specific cleanup. */
+ module_arch_cleanup(mod);
+
+ /* Module unload stuff */
+ module_unload_free(mod);
+
+ /* This may be NULL, but that's OK */
+ module_free(mod, mod->module_init);
+ kfree(mod->args);
+ if (mod->percpu)
+ percpu_modfree(mod->percpu);
+
+ /* 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, flags;
+ const unsigned long *crc;
+
+ spin_lock_irqsave(&modlist_lock, flags);
+ value = __find_symbol(symbol, &owner, &crc, 1);
+ if (value && !strong_try_module_get(owner))
+ value = 0;
+ spin_unlock_irqrestore(&modlist_lock, flags);
+
+ return (void *)value;
+}
+EXPORT_SYMBOL_GPL(__symbol_get);
+
+/* Change all symbols so that sh_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 (sym[i].st_value != 0)
+ 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 long *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 inline int license_is_gpl_compatible(const char *license)
+{
+ return (strcmp(license, "GPL") == 0
+ || strcmp(license, "GPL v2") == 0
+ || strcmp(license, "GPL and additional rights") == 0
+ || strcmp(license, "Dual BSD/GPL") == 0
+ || strcmp(license, "Dual MPL/GPL") == 0);
+}
+
+static void set_license(struct module *mod, const char *license)
+{
+ if (!license)
+ license = "unspecified";
+
+ mod->license_gplok = license_is_gpl_compatible(license);
+ if (!mod->license_gplok && !(tainted & TAINT_PROPRIETARY_MODULE)) {
+ printk(KERN_WARNING "%s: module license '%s' taints kernel.\n",
+ mod->name, license);
+ tainted |= 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;
+}
+
+#ifdef CONFIG_KALLSYMS
+int is_exported(const char *name, const struct module *mod)
+{
+ unsigned int i;
+
+ if (!mod) {
+ for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++)
+ if (strcmp(__start___ksymtab[i].name, name) == 0)
+ return 1;
+ return 0;
+ }
+ for (i = 0; i < mod->num_syms; i++)
+ if (strcmp(mod->syms[i].name, name) == 0)
+ return 1;
+ 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 */
+
+/* Allocate and load the module: note that size of section 0 is always
+ zero, and we rely on this for optional sections. */
+static 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;
+ unsigned int i, symindex = 0, strindex = 0, setupindex, exindex,
+ exportindex, modindex, obsparmindex, infoindex, gplindex,
+ crcindex, gplcrcindex, versindex, pcpuindex;
+ long arglen;
+ struct module *mod;
+ long err = 0;
+ void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
+ struct exception_table_entry *extable;
+
+ 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, 4) != 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;
+ }
+ 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;
+ }
+
+ /* Optional sections */
+ exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
+ gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
+ crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
+ gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
+ setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
+ exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
+ obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
+ versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
+ infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
+ pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
+
+ /* Don't keep modinfo section */
+ sechdrs[infoindex].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
+
+ /* 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) {
+ tainted |= TAINT_FORCED_MODULE;
+ printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
+ mod->name);
+ } else if (!same_magic(modmagic, vermagic)) {
+ printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
+ mod->name, modmagic, vermagic);
+ err = -ENOEXEC;
+ goto free_hdr;
+ }
+
+ /* Now copy in args */
+ arglen = strlen_user(uargs);
+ if (!arglen) {
+ err = -EFAULT;
+ goto free_hdr;
+ }
+ args = kmalloc(arglen, GFP_KERNEL);
+ if (!args) {
+ err = -ENOMEM;
+ goto free_hdr;
+ }
+ if (copy_from_user(args, uargs, arglen) != 0) {
+ err = -EFAULT;
+ goto free_mod;
+ }
+
+ 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);
+ 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(mod->core_size);
+ if (!ptr) {
+ err = -ENOMEM;
+ goto free_percpu;
+ }
+ memset(ptr, 0, mod->core_size);
+ mod->module_core = ptr;
+
+ ptr = module_alloc(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);
+
+ /* Set up license info based on the info section */
+ set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
+
+ /* 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;
+
+ /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
+ mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
+ mod->syms = (void *)sechdrs[exportindex].sh_addr;
+ if (crcindex)
+ mod->crcs = (void *)sechdrs[crcindex].sh_addr;
+ mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
+ mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
+ if (gplcrcindex)
+ mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
+
+#ifdef CONFIG_MODVERSIONS
+ if ((mod->num_syms && !crcindex) ||
+ (mod->num_gpl_syms && !gplcrcindex)) {
+ printk(KERN_WARNING "%s: No versions for exported symbols."
+ " Tainting kernel.\n", mod->name);
+ tainted |= TAINT_FORCED_MODULE;
+ }
+#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;
+ }
+
+ /* Set up and sort exception table */
+ mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
+ mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
+ sort_extable(extable, 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);
+
+ err = module_finalize(hdr, sechdrs, mod);
+ if (err < 0)
+ goto cleanup;
+
+ mod->args = args;
+ if (obsparmindex) {
+ err = obsolete_params(mod->name, mod->args,
+ (struct obsolete_modparm *)
+ sechdrs[obsparmindex].sh_addr,
+ sechdrs[obsparmindex].sh_size
+ / sizeof(struct obsolete_modparm),
+ sechdrs, symindex,
+ (char *)sechdrs[strindex].sh_addr);
+ if (setupindex)
+ printk(KERN_WARNING "%s: Ignoring new-style "
+ "parameters in presence of obsolete ones\n",
+ mod->name);
+ } else {
+ /* Size of section 0 is 0, so this works well if no params */
+ err = parse_args(mod->name, mod->args,
+ (struct kernel_param *)
+ sechdrs[setupindex].sh_addr,
+ sechdrs[setupindex].sh_size
+ / sizeof(struct kernel_param),
+ NULL);
+ }
+ if (err < 0)
+ goto arch_cleanup;
+
+ err = mod_sysfs_setup(mod,
+ (struct kernel_param *)
+ sechdrs[setupindex].sh_addr,
+ sechdrs[setupindex].sh_size
+ / sizeof(struct kernel_param));
+ if (err < 0)
+ goto arch_cleanup;
+ add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
+
+ /* Get rid of temporary copy */
+ vfree(hdr);
+
+ /* Done! */
+ return mod;
+
+ arch_cleanup:
+ module_arch_cleanup(mod);
+ cleanup:
+ 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);
+ if (err < 0) return ERR_PTR(err);
+ else return ptr;
+
+ truncated:
+ printk(KERN_ERR "Module len %lu truncated\n", len);
+ err = -ENOEXEC;
+ goto free_hdr;
+}
+
+/*
+ * link the module with the whole machine is stopped with interrupts off
+ * - this defends against kallsyms not taking locks
+ */
+static int __link_module(void *_mod)
+{
+ struct module *mod = _mod;
+ list_add(&mod->list, &modules);
+ return 0;
+}
+
+/* This is where the real work happens */
+asmlinkage long
+sys_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 (down_interruptible(&module_mutex) != 0)
+ return -EINTR;
+
+ /* Do all the hard work */
+ mod = load_module(umod, len, uargs);
+ if (IS_ERR(mod)) {
+ up(&module_mutex);
+ return PTR_ERR(mod);
+ }
+
+ /* Flush the instruction cache, since we've played with text */
+ 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);
+
+ /* Now sew it into the lists. They won't access us, since
+ strong_try_module_get() will fail. */
+ stop_machine_run(__link_module, mod, NR_CPUS);
+
+ /* Drop lock so they can recurse */
+ up(&module_mutex);
+
+ down(&notify_mutex);
+ notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod);
+ up(&notify_mutex);
+
+ /* Start the module */
+ if (mod->init != NULL)
+ ret = mod->init();
+ if (ret < 0) {
+ /* Init routine failed: abort. Try to protect us from
+ buggy refcounters. */
+ mod->state = MODULE_STATE_GOING;
+ synchronize_kernel();
+ if (mod->unsafe)
+ printk(KERN_ERR "%s: module is now stuck!\n",
+ mod->name);
+ else {
+ module_put(mod);
+ down(&module_mutex);
+ free_module(mod);
+ up(&module_mutex);
+ }
+ return ret;
+ }
+
+ /* Now it's a first class citizen! */
+ down(&module_mutex);
+ mod->state = MODULE_STATE_LIVE;
+ /* Drop initial reference. */
+ module_put(mod);
+ module_free(mod, mod->module_init);
+ mod->module_init = NULL;
+ mod->init_size = 0;
+ mod->init_text_size = 0;
+ up(&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;
+
+ *size = nextval - mod->symtab[best].st_value;
+ *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.
+ We don't lock, as this is used for oops resolution and races are a
+ lesser concern. */
+const char *module_address_lookup(unsigned long addr,
+ unsigned long *size,
+ unsigned long *offset,
+ char **modname)
+{
+ struct module *mod;
+
+ list_for_each_entry(mod, &modules, list) {
+ if (within(addr, mod->module_init, mod->init_size)
+ || within(addr, mod->module_core, mod->core_size)) {
+ *modname = mod->name;
+ return get_ksymbol(mod, addr, size, offset);
+ }
+ }
+ return NULL;
+}
+
+struct module *module_get_kallsym(unsigned int symnum,
+ unsigned long *value,
+ char *type,
+ char namebuf[128])
+{
+ struct module *mod;
+
+ down(&module_mutex);
+ list_for_each_entry(mod, &modules, list) {
+ if (symnum < mod->num_symtab) {
+ *value = mod->symtab[symnum].st_value;
+ *type = mod->symtab[symnum].st_info;
+ strncpy(namebuf,
+ mod->strtab + mod->symtab[symnum].st_name,
+ 127);
+ up(&module_mutex);
+ return mod;
+ }
+ symnum -= mod->num_symtab;
+ }
+ up(&module_mutex);
+ return NULL;
+}
+
+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)
+ 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. */
+ 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(mod, &modules, list)
+ if ((ret = mod_find_symname(mod, name)) != 0)
+ break;
+ }
+ return ret;
+}
+#endif /* CONFIG_KALLSYMS */
+
+/* Called by the /proc file system to return a list of modules. */
+static void *m_start(struct seq_file *m, loff_t *pos)
+{
+ struct list_head *i;
+ loff_t n = 0;
+
+ down(&module_mutex);
+ list_for_each(i, &modules) {
+ if (n++ == *pos)
+ break;
+ }
+ if (i == &modules)
+ return NULL;
+ return i;
+}
+
+static void *m_next(struct seq_file *m, void *p, loff_t *pos)
+{
+ struct list_head *i = p;
+ (*pos)++;
+ if (i->next == &modules)
+ return NULL;
+ return i->next;
+}
+
+static void m_stop(struct seq_file *m, void *p)
+{
+ up(&module_mutex);
+}
+
+static int m_show(struct seq_file *m, void *p)
+{
+ struct module *mod = list_entry(p, struct module, list);
+ seq_printf(m, "%s %lu",
+ 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);
+
+ 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 -.
+*/
+struct seq_operations modules_op = {
+ .start = m_start,
+ .next = m_next,
+ .stop = m_stop,
+ .show = m_show
+};
+
+/* Given an address, look for it in the module exception tables. */
+const struct exception_table_entry *search_module_extables(unsigned long addr)
+{
+ unsigned long flags;
+ const struct exception_table_entry *e = NULL;
+ struct module *mod;
+
+ spin_lock_irqsave(&modlist_lock, flags);
+ list_for_each_entry(mod, &modules, list) {
+ if (mod->num_exentries == 0)
+ continue;
+
+ e = search_extable(mod->extable,
+ mod->extable + mod->num_exentries - 1,
+ addr);
+ if (e)
+ break;
+ }
+ spin_unlock_irqrestore(&modlist_lock, flags);
+
+ /* 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 kernel address? We don't grab the lock: we are oopsing. */
+struct module *__module_text_address(unsigned long addr)
+{
+ struct module *mod;
+
+ list_for_each_entry(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;
+ unsigned long flags;
+
+ spin_lock_irqsave(&modlist_lock, flags);
+ mod = __module_text_address(addr);
+ spin_unlock_irqrestore(&modlist_lock, flags);
+
+ return mod;
+}
+
+/* Don't grab lock, we're oopsing. */
+void print_modules(void)
+{
+ struct module *mod;
+
+ printk("Modules linked in:");
+ list_for_each_entry(mod, &modules, list)
+ printk(" %s", mod->name);
+ printk("\n");
+}
+
+void module_add_driver(struct module *mod, struct device_driver *drv)
+{
+ if (!mod || !drv)
+ return;
+
+ /* Don't check return code; this call is idempotent */
+ sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
+}
+EXPORT_SYMBOL(module_add_driver);
+
+void module_remove_driver(struct device_driver *drv)
+{
+ if (!drv)
+ return;
+ sysfs_remove_link(&drv->kobj, "module");
+}
+EXPORT_SYMBOL(module_remove_driver);
+
+#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