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Diffstat (limited to 'kernel/module.c')
-rw-r--r--kernel/module.c59
1 files changed, 44 insertions, 15 deletions
diff --git a/kernel/module.c b/kernel/module.c
index dd2a54155b5..f47cce910f2 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -757,8 +757,16 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
return -EFAULT;
name[MODULE_NAME_LEN-1] = '\0';
- if (mutex_lock_interruptible(&module_mutex) != 0)
- return -EINTR;
+ /* Create stop_machine threads since free_module relies on
+ * a non-failing stop_machine call. */
+ ret = stop_machine_create();
+ if (ret)
+ return ret;
+
+ if (mutex_lock_interruptible(&module_mutex) != 0) {
+ ret = -EINTR;
+ goto out_stop;
+ }
mod = find_module(name);
if (!mod) {
@@ -817,10 +825,12 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
out:
mutex_unlock(&module_mutex);
+out_stop:
+ stop_machine_destroy();
return ret;
}
-static void print_unload_info(struct seq_file *m, struct module *mod)
+static inline void print_unload_info(struct seq_file *m, struct module *mod)
{
struct module_use *use;
int printed_something = 0;
@@ -893,7 +903,7 @@ void module_put(struct module *module)
EXPORT_SYMBOL(module_put);
#else /* !CONFIG_MODULE_UNLOAD */
-static void print_unload_info(struct seq_file *m, struct module *mod)
+static inline 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, " - -");
@@ -1578,11 +1588,21 @@ static int simplify_symbols(Elf_Shdr *sechdrs,
return ret;
}
+/* Additional bytes needed by arch in front of individual sections */
+unsigned int __weak arch_mod_section_prepend(struct module *mod,
+ unsigned int section)
+{
+ /* default implementation just returns zero */
+ return 0;
+}
+
/* Update size with this section: return offset. */
-static long get_offset(unsigned int *size, Elf_Shdr *sechdr)
+static long get_offset(struct module *mod, unsigned int *size,
+ Elf_Shdr *sechdr, unsigned int section)
{
long ret;
+ *size += arch_mod_section_prepend(mod, section);
ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
*size = ret + sechdr->sh_size;
return ret;
@@ -1622,7 +1642,7 @@ static void layout_sections(struct module *mod,
|| strncmp(secstrings + s->sh_name,
".init", 5) == 0)
continue;
- s->sh_entsize = get_offset(&mod->core_size, s);
+ s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
DEBUGP("\t%s\n", secstrings + s->sh_name);
}
if (m == 0)
@@ -1640,7 +1660,7 @@ static void layout_sections(struct module *mod,
|| strncmp(secstrings + s->sh_name,
".init", 5) != 0)
continue;
- s->sh_entsize = (get_offset(&mod->init_size, s)
+ s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
| INIT_OFFSET_MASK);
DEBUGP("\t%s\n", secstrings + s->sh_name);
}
@@ -1725,15 +1745,15 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
return NULL;
}
-static int is_exported(const char *name, const struct module *mod)
+static int is_exported(const char *name, unsigned long value,
+ const struct module *mod)
{
- if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
- return 1;
+ const struct kernel_symbol *ks;
+ if (!mod)
+ ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
else
- if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
- return 1;
- else
- return 0;
+ ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
+ return ks != NULL && ks->value == value;
}
/* As per nm */
@@ -1865,6 +1885,13 @@ static noinline struct module *load_module(void __user *umod,
/* vmalloc barfs on "unusual" numbers. Check here */
if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
return ERR_PTR(-ENOMEM);
+
+ /* Create stop_machine threads since the error path relies on
+ * a non-failing stop_machine call. */
+ err = stop_machine_create();
+ if (err)
+ goto free_hdr;
+
if (copy_from_user(hdr, umod, len) != 0) {
err = -EFAULT;
goto free_hdr;
@@ -2248,6 +2275,7 @@ static noinline struct module *load_module(void __user *umod,
/* Get rid of temporary copy */
vfree(hdr);
+ stop_machine_destroy();
/* Done! */
return mod;
@@ -2270,6 +2298,7 @@ static noinline struct module *load_module(void __user *umod,
kfree(args);
free_hdr:
vfree(hdr);
+ stop_machine_destroy();
return ERR_PTR(err);
truncated:
@@ -2504,7 +2533,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
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);
+ *exported = is_exported(name, *value, mod);
preempt_enable();
return 0;
}