aboutsummaryrefslogtreecommitdiff
path: root/kernel/module.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/module.c')
-rw-r--r--kernel/module.c94
1 files changed, 56 insertions, 38 deletions
diff --git a/kernel/module.c b/kernel/module.c
index dd2a54155b5..c9332c90d5a 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -43,7 +43,6 @@
#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>
@@ -51,6 +50,7 @@
#include <asm/sections.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
+#include <linux/async.h>
#if 0
#define DEBUGP printk
@@ -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) {
@@ -809,6 +817,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
mod->exit();
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ async_synchronize_full();
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));
@@ -817,10 +826,12 @@ 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 +904,7 @@ 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, " - -");
@@ -1439,8 +1450,6 @@ static void free_module(struct module *mod)
remove_sect_attrs(mod);
mod_kobject_remove(mod);
- unwind_remove_table(mod->unwind_info, 0);
-
/* Arch-specific cleanup. */
module_arch_cleanup(mod);
@@ -1578,11 +1587,21 @@ 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 +1641,7 @@ 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 +1659,7 @@ 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 +1744,15 @@ 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 */
@@ -1847,7 +1866,6 @@ static noinline struct module *load_module(void __user *umod,
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;
@@ -1865,6 +1883,13 @@ 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;
@@ -1930,9 +1955,6 @@ static noinline struct module *load_module(void __user *umod,
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;
@@ -1942,8 +1964,6 @@ static noinline struct module *load_module(void __user *umod,
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)) {
@@ -2240,14 +2260,10 @@ static noinline struct module *load_module(void __user *umod,
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);
+ stop_machine_destroy();
/* Done! */
return mod;
@@ -2270,6 +2286,7 @@ static noinline struct module *load_module(void __user *umod,
kfree(args);
free_hdr:
vfree(hdr);
+ stop_machine_destroy();
return ERR_PTR(err);
truncated:
@@ -2337,11 +2354,12 @@ sys_init_module(void __user *umod,
/* Now it's a first class citizen! Wake up anyone waiting for it. */
mod->state = MODULE_STATE_LIVE;
wake_up(&module_wq);
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_LIVE, mod);
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;
@@ -2376,7 +2394,7 @@ static const char *get_ksymbol(struct module *mod,
unsigned long nextval;
/* At worse, next value is at end of module */
- if (within(addr, mod->module_init, mod->init_size))
+ if (within_module_init(addr, mod))
nextval = (unsigned long)mod->module_init+mod->init_text_size;
else
nextval = (unsigned long)mod->module_core+mod->core_text_size;
@@ -2424,8 +2442,8 @@ const char *module_address_lookup(unsigned long addr,
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 (within_module_init(addr, mod) ||
+ within_module_core(addr, mod)) {
if (modname)
*modname = mod->name;
ret = get_ksymbol(mod, addr, size, offset);
@@ -2447,8 +2465,8 @@ int lookup_module_symbol_name(unsigned long addr, char *symname)
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 (within_module_init(addr, mod) ||
+ within_module_core(addr, mod)) {
const char *sym;
sym = get_ksymbol(mod, addr, NULL, NULL);
@@ -2471,8 +2489,8 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
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 (within_module_init(addr, mod) ||
+ within_module_core(addr, mod)) {
const char *sym;
sym = get_ksymbol(mod, addr, size, offset);
@@ -2504,7 +2522,7 @@ 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;
}
@@ -2691,7 +2709,7 @@ int is_module_address(unsigned long addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
- if (within(addr, mod->module_core, mod->core_size)) {
+ if (within_module_core(addr, mod)) {
preempt_enable();
return 1;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-17 07:49:38 +0000