From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx>
In order to use execmem's API for temporal remapping of the memory
allocated from ROX cache as writable, there is a need to distinguish
between the state when the module is being formed and the state when it is
deconstructed and freed so that when module_memory_free() is called from
error paths during module loading it could restore ROX mappings.
Replace open coded checks for MODULE_STATE_UNFORMED with a helper
function module_is_formed() and add a new MODULE_STATE_GONE that will be
set when the module is deconstructed and freed.
Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
---
include/linux/module.h | 6 ++++++
kernel/module/kallsyms.c | 8 ++++----
kernel/module/kdb.c | 2 +-
kernel/module/main.c | 19 +++++++++----------
kernel/module/procfs.c | 2 +-
kernel/tracepoint.c | 2 ++
lib/kunit/test.c | 2 ++
samples/livepatch/livepatch-callbacks-demo.c | 1 +
.../test_modules/test_klp_callbacks_demo.c | 1 +
.../test_modules/test_klp_callbacks_demo2.c | 1 +
.../livepatch/test_modules/test_klp_state.c | 1 +
.../livepatch/test_modules/test_klp_state2.c | 1 +
12 files changed, 30 insertions(+), 16 deletions(-)
diff --git a/include/linux/module.h b/include/linux/module.h
index 94acbacdcdf1..bd8cf93d32c8 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -320,6 +320,7 @@ enum module_state {
MODULE_STATE_COMING, /* Full formed, running module_init. */
MODULE_STATE_GOING, /* Going away. */
MODULE_STATE_UNFORMED, /* Still setting it up. */
+ MODULE_STATE_GONE, /* Deconstructing and freeing. */
};
struct mod_tree_node {
@@ -620,6 +621,11 @@ static inline bool module_is_coming(struct module *mod)
return mod->state == MODULE_STATE_COMING;
}
+static inline bool module_is_formed(struct module *mod)
+{
+ return mod->state < MODULE_STATE_UNFORMED;
+}
+
struct module *__module_text_address(unsigned long addr);
struct module *__module_address(unsigned long addr);
bool is_module_address(unsigned long addr);
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
index bf65e0c3c86f..daf9a9b3740f 100644
--- a/kernel/module/kallsyms.c
+++ b/kernel/module/kallsyms.c
@@ -361,7 +361,7 @@ int lookup_module_symbol_name(unsigned long addr, char *symname)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
if (within_module(addr, mod)) {
const char *sym;
@@ -389,7 +389,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
list_for_each_entry_rcu(mod, &modules, list) {
struct mod_kallsyms *kallsyms;
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
kallsyms = rcu_dereference_sched(mod->kallsyms);
if (symnum < kallsyms->num_symtab) {
@@ -441,7 +441,7 @@ static unsigned long __module_kallsyms_lookup_name(const char *name)
list_for_each_entry_rcu(mod, &modules, list) {
unsigned long ret;
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
ret = __find_kallsyms_symbol_value(mod, name);
if (ret)
@@ -484,7 +484,7 @@ int module_kallsyms_on_each_symbol(const char *modname,
list_for_each_entry(mod, &modules, list) {
struct mod_kallsyms *kallsyms;
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
if (modname && strcmp(modname, mod->name))
diff --git a/kernel/module/kdb.c b/kernel/module/kdb.c
index 995c32d3698f..14f14700ffc2 100644
--- a/kernel/module/kdb.c
+++ b/kernel/module/kdb.c
@@ -23,7 +23,7 @@ int kdb_lsmod(int argc, const char **argv)
kdb_printf("Module Size modstruct Used by\n");
list_for_each_entry(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
kdb_printf("%-20s%8u", mod->name, mod->mem[MOD_TEXT].size);
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 5399c182b3cb..ad8ef20c120f 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -153,7 +153,7 @@ EXPORT_SYMBOL(unregister_module_notifier);
*/
static inline int strong_try_module_get(struct module *mod)
{
- BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
+ BUG_ON(mod && !module_is_formed(mod));
if (mod && mod->state == MODULE_STATE_COMING)
return -EBUSY;
if (try_module_get(mod))
@@ -361,7 +361,7 @@ bool find_symbol(struct find_symbol_arg *fsa)
GPL_ONLY },
};
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
for (i = 0; i < ARRAY_SIZE(arr); i++)
@@ -386,7 +386,7 @@ struct module *find_module_all(const char *name, size_t len,
list_for_each_entry_rcu(mod, &modules, list,
lockdep_is_held(&module_mutex)) {
- if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
+ if (!even_unformed && !module_is_formed(mod))
continue;
if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
return mod;
@@ -457,7 +457,7 @@ bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
if (!mod->percpu_size)
continue;
@@ -1326,7 +1326,7 @@ static void free_module(struct module *mod)
* that noone uses it while it's being deconstructed.
*/
mutex_lock(&module_mutex);
- mod->state = MODULE_STATE_UNFORMED;
+ mod->state = MODULE_STATE_GONE;
mutex_unlock(&module_mutex);
/* Arch-specific cleanup. */
@@ -3048,8 +3048,7 @@ static int module_patient_check_exists(const char *name,
if (old == NULL)
return 0;
- if (old->state == MODULE_STATE_COMING ||
- old->state == MODULE_STATE_UNFORMED) {
+ if (old->state == MODULE_STATE_COMING || !module_is_formed(old)) {
/* Wait in case it fails to load. */
mutex_unlock(&module_mutex);
err = wait_event_interruptible(module_wq,
@@ -3608,7 +3607,7 @@ char *module_flags(struct module *mod, char *buf, bool show_state)
{
int bx = 0;
- BUG_ON(mod->state == MODULE_STATE_UNFORMED);
+ BUG_ON(!module_is_formed(mod));
if (!mod->taints && !show_state)
goto out;
if (mod->taints ||
@@ -3702,7 +3701,7 @@ struct module *__module_address(unsigned long addr)
mod = mod_find(addr, &mod_tree);
if (mod) {
BUG_ON(!within_module(addr, mod));
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
mod = NULL;
}
return mod;
@@ -3756,7 +3755,7 @@ void print_modules(void)
/* Most callers should already have preempt disabled, but make sure */
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
continue;
pr_cont(" %s%s", mod->name, module_flags(mod, buf, true));
}
diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c
index 0a4841e88adb..2c617e6f8bc0 100644
--- a/kernel/module/procfs.c
+++ b/kernel/module/procfs.c
@@ -79,7 +79,7 @@ static int m_show(struct seq_file *m, void *p)
unsigned int size;
/* We always ignore unformed modules. */
- if (mod->state == MODULE_STATE_UNFORMED)
+ if (!module_is_formed(mod))
return 0;
size = module_total_size(mod);
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 1848ce7e2976..e94247afb2c6 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -668,6 +668,8 @@ static int tracepoint_module_notify(struct notifier_block *self,
break;
case MODULE_STATE_UNFORMED:
break;
+ case MODULE_STATE_GONE:
+ break;
}
return notifier_from_errno(ret);
}
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index 089c832e3cdb..54eaed92a2d3 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -836,6 +836,8 @@ static int kunit_module_notify(struct notifier_block *nb, unsigned long val,
break;
case MODULE_STATE_UNFORMED:
break;
+ case MODULE_STATE_GONE:
+ break;
}
return 0;
diff --git a/samples/livepatch/livepatch-callbacks-demo.c b/samples/livepatch/livepatch-callbacks-demo.c
index 11c3f4357812..324bddaef9a6 100644
--- a/samples/livepatch/livepatch-callbacks-demo.c
+++ b/samples/livepatch/livepatch-callbacks-demo.c
@@ -93,6 +93,7 @@ static const char *const module_state[] = {
[MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
[MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
[MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
+ [MODULE_STATE_GONE] = "[MODULE_STATE_GONE] Deconstructing and freeing",
};
static void callback_info(const char *callback, struct klp_object *obj)
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
index 3fd8fe1cd1cc..8435e3254f85 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
@@ -16,6 +16,7 @@ static const char *const module_state[] = {
[MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
[MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
[MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
+ [MODULE_STATE_GONE] = "[MODULE_STATE_GONE] Deconstructing and freeing",
};
static void callback_info(const char *callback, struct klp_object *obj)
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
index 5417573e80af..78c1fff5d977 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
@@ -16,6 +16,7 @@ static const char *const module_state[] = {
[MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
[MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
[MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
+ [MODULE_STATE_GONE] = "[MODULE_STATE_GONE] Deconstructing and freeing",
};
static void callback_info(const char *callback, struct klp_object *obj)
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_state.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
index 57a4253acb01..bdebf1d24c98 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
@@ -18,6 +18,7 @@ static const char *const module_state[] = {
[MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
[MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
[MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
+ [MODULE_STATE_GONE] = "[MODULE_STATE_GONE] Deconstructing and freeing",
};
static void callback_info(const char *callback, struct klp_object *obj)
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
index c978ea4d5e67..1a55f84a8eb3 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
@@ -18,6 +18,7 @@ static const char *const module_state[] = {
[MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
[MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
[MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
+ [MODULE_STATE_GONE] = "[MODULE_STATE_GONE] Deconstructing and freeing",
};
static void callback_info(const char *callback, struct klp_object *obj)
--
2.45.2
