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-rw-r--r--kernel/module.c107
1 files changed, 62 insertions, 45 deletions
diff --git a/kernel/module.c b/kernel/module.c
index cab4bce49c2..dc582749fa1 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -136,6 +136,7 @@ static int param_set_bool_enable_only(const char *val,
}
static const struct kernel_param_ops param_ops_bool_enable_only = {
+ .flags = KERNEL_PARAM_FL_NOARG,
.set = param_set_bool_enable_only,
.get = param_get_bool,
};
@@ -455,7 +456,7 @@ const struct kernel_symbol *find_symbol(const char *name,
EXPORT_SYMBOL_GPL(find_symbol);
/* Search for module by name: must hold module_mutex. */
-static struct module *find_module_all(const char *name,
+static struct module *find_module_all(const char *name, size_t len,
bool even_unformed)
{
struct module *mod;
@@ -463,7 +464,7 @@ static struct module *find_module_all(const char *name,
list_for_each_entry(mod, &modules, list) {
if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
continue;
- if (strcmp(mod->name, name) == 0)
+ if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
return mod;
}
return NULL;
@@ -471,7 +472,7 @@ static struct module *find_module_all(const char *name,
struct module *find_module(const char *name)
{
- return find_module_all(name, false);
+ return find_module_all(name, strlen(name), false);
}
EXPORT_SYMBOL_GPL(find_module);
@@ -482,23 +483,28 @@ static inline void __percpu *mod_percpu(struct module *mod)
return mod->percpu;
}
-static int percpu_modalloc(struct module *mod,
- unsigned long size, unsigned long align)
+static int percpu_modalloc(struct module *mod, struct load_info *info)
{
+ Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
+ unsigned long align = pcpusec->sh_addralign;
+
+ if (!pcpusec->sh_size)
+ return 0;
+
if (align > PAGE_SIZE) {
printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
mod->name, align, PAGE_SIZE);
align = PAGE_SIZE;
}
- mod->percpu = __alloc_reserved_percpu(size, align);
+ mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
if (!mod->percpu) {
printk(KERN_WARNING
"%s: Could not allocate %lu bytes percpu data\n",
- mod->name, size);
+ mod->name, (unsigned long)pcpusec->sh_size);
return -ENOMEM;
}
- mod->percpu_size = size;
+ mod->percpu_size = pcpusec->sh_size;
return 0;
}
@@ -563,10 +569,12 @@ static inline void __percpu *mod_percpu(struct module *mod)
{
return NULL;
}
-static inline int percpu_modalloc(struct module *mod,
- unsigned long size, unsigned long align)
+static int percpu_modalloc(struct module *mod, struct load_info *info)
{
- return -ENOMEM;
+ /* UP modules shouldn't have this section: ENOMEM isn't quite right */
+ if (info->sechdrs[info->index.pcpu].sh_size != 0)
+ return -ENOMEM;
+ return 0;
}
static inline void percpu_modfree(struct module *mod)
{
@@ -596,7 +604,7 @@ static void setup_modinfo_##field(struct module *mod, const char *s) \
static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
struct module_kobject *mk, char *buffer) \
{ \
- return sprintf(buffer, "%s\n", mk->mod->field); \
+ return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
} \
static int modinfo_##field##_exists(struct module *mod) \
{ \
@@ -1604,6 +1612,14 @@ static void module_remove_modinfo_attrs(struct module *mod)
kfree(mod->modinfo_attrs);
}
+static void mod_kobject_put(struct module *mod)
+{
+ DECLARE_COMPLETION_ONSTACK(c);
+ mod->mkobj.kobj_completion = &c;
+ kobject_put(&mod->mkobj.kobj);
+ wait_for_completion(&c);
+}
+
static int mod_sysfs_init(struct module *mod)
{
int err;
@@ -1631,7 +1647,7 @@ static int mod_sysfs_init(struct module *mod)
err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
"%s", mod->name);
if (err)
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
/* delay uevent until full sysfs population */
out:
@@ -1675,7 +1691,7 @@ out_unreg_param:
out_unreg_holders:
kobject_put(mod->holders_dir);
out_unreg:
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
out:
return err;
}
@@ -1684,7 +1700,7 @@ static void mod_sysfs_fini(struct module *mod)
{
remove_notes_attrs(mod);
remove_sect_attrs(mod);
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
}
#else /* !CONFIG_SYSFS */
@@ -2533,21 +2549,20 @@ static int copy_module_from_user(const void __user *umod, unsigned long len,
/* Sets info->hdr and info->len. */
static int copy_module_from_fd(int fd, struct load_info *info)
{
- struct file *file;
+ struct fd f = fdget(fd);
int err;
struct kstat stat;
loff_t pos;
ssize_t bytes = 0;
- file = fget(fd);
- if (!file)
+ if (!f.file)
return -ENOEXEC;
- err = security_kernel_module_from_file(file);
+ err = security_kernel_module_from_file(f.file);
if (err)
goto out;
- err = vfs_getattr(&file->f_path, &stat);
+ err = vfs_getattr(&f.file->f_path, &stat);
if (err)
goto out;
@@ -2570,7 +2585,7 @@ static int copy_module_from_fd(int fd, struct load_info *info)
pos = 0;
while (pos < stat.size) {
- bytes = kernel_read(file, pos, (char *)(info->hdr) + pos,
+ bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
stat.size - pos);
if (bytes < 0) {
vfree(info->hdr);
@@ -2584,7 +2599,7 @@ static int copy_module_from_fd(int fd, struct load_info *info)
info->len = pos;
out:
- fput(file);
+ fdput(f);
return err;
}
@@ -2927,7 +2942,6 @@ static struct module *layout_and_allocate(struct load_info *info, int flags)
{
/* Module within temporary copy. */
struct module *mod;
- Elf_Shdr *pcpusec;
int err;
mod = setup_load_info(info, flags);
@@ -2942,17 +2956,10 @@ static struct module *layout_and_allocate(struct load_info *info, int flags)
err = module_frob_arch_sections(info->hdr, info->sechdrs,
info->secstrings, mod);
if (err < 0)
- goto out;
+ return ERR_PTR(err);
- pcpusec = &info->sechdrs[info->index.pcpu];
- if (pcpusec->sh_size) {
- /* We have a special allocation for this section. */
- err = percpu_modalloc(mod,
- pcpusec->sh_size, pcpusec->sh_addralign);
- if (err)
- goto out;
- pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC;
- }
+ /* We will do a special allocation for per-cpu sections later. */
+ info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
/* Determine total sizes, and put offsets in sh_entsize. For now
this is done generically; there doesn't appear to be any
@@ -2963,17 +2970,12 @@ static struct module *layout_and_allocate(struct load_info *info, int flags)
/* Allocate and move to the final place */
err = move_module(mod, info);
if (err)
- goto free_percpu;
+ return ERR_PTR(err);
/* Module has been copied to its final place now: return it. */
mod = (void *)info->sechdrs[info->index.mod].sh_addr;
kmemleak_load_module(mod, info);
return mod;
-
-free_percpu:
- percpu_modfree(mod);
-out:
- return ERR_PTR(err);
}
/* mod is no longer valid after this! */
@@ -3014,7 +3016,7 @@ static bool finished_loading(const char *name)
bool ret;
mutex_lock(&module_mutex);
- mod = find_module_all(name, true);
+ mod = find_module_all(name, strlen(name), true);
ret = !mod || mod->state == MODULE_STATE_LIVE
|| mod->state == MODULE_STATE_GOING;
mutex_unlock(&module_mutex);
@@ -3152,7 +3154,8 @@ static int add_unformed_module(struct module *mod)
again:
mutex_lock(&module_mutex);
- if ((old = find_module_all(mod->name, true)) != NULL) {
+ old = find_module_all(mod->name, strlen(mod->name), true);
+ if (old != NULL) {
if (old->state == MODULE_STATE_COMING
|| old->state == MODULE_STATE_UNFORMED) {
/* Wait in case it fails to load. */
@@ -3198,6 +3201,17 @@ out:
return err;
}
+static int unknown_module_param_cb(char *param, char *val, const char *modname)
+{
+ /* Check for magic 'dyndbg' arg */
+ int ret = ddebug_dyndbg_module_param_cb(param, val, modname);
+ if (ret != 0) {
+ printk(KERN_WARNING "%s: unknown parameter '%s' ignored\n",
+ modname, param);
+ }
+ return 0;
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static int load_module(struct load_info *info, const char __user *uargs,
@@ -3237,6 +3251,11 @@ static int load_module(struct load_info *info, const char __user *uargs,
}
#endif
+ /* To avoid stressing percpu allocator, do this once we're unique. */
+ err = percpu_modalloc(mod, info);
+ if (err)
+ goto unlink_mod;
+
/* Now module is in final location, initialize linked lists, etc. */
err = module_unload_init(mod);
if (err)
@@ -3284,7 +3303,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Module is ready to execute: parsing args may do that. */
err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
- -32768, 32767, &ddebug_dyndbg_module_param_cb);
+ -32768, 32767, unknown_module_param_cb);
if (err < 0)
goto bug_cleanup;
@@ -3563,10 +3582,8 @@ unsigned long module_kallsyms_lookup_name(const char *name)
/* Don't lock: we're in enough trouble already. */
preempt_disable();
if ((colon = strchr(name, ':')) != NULL) {
- *colon = '\0';
- if ((mod = find_module(name)) != NULL)
+ if ((mod = find_module_all(name, colon - name, false)) != NULL)
ret = mod_find_symname(mod, colon+1);
- *colon = ':';
} else {
list_for_each_entry_rcu(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)