Commit e3350aa0 authored by Zheng Yejian's avatar Zheng Yejian
Browse files

livepatch: Bypass dead thread when check calltrace 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8MGE6



--------------------------------

When the thread become zombie or dead, it's stack memory may
have been freed, so ignore it.

Signed-off-by: default avatarZheng Yejian <zhengyejian1@huawei.com>
parent 7a3d8e41

arch/arm/kernel/livepatch.c

+2 −0
Original line number Diff line number Diff line
@@ -119,6 +119,8 @@ static int do_check_calltrace(struct walk_stackframe_args *args, 
	for_each_process_thread(g, t) {

		if (klp_is_migration_thread(t->comm))

			continue;

		if (klp_is_thread_dead(t))

			continue;

		ret = check_task_calltrace(t, args, fn);

		if (ret)

			return ret;

arch/arm64/kernel/livepatch.c

+2 −0
Original line number Diff line number Diff line
@@ -97,6 +97,8 @@ static int do_check_calltrace(struct walk_stackframe_args *args, 
	for_each_process_thread(g, t) {

		if (klp_is_migration_thread(t->comm))

			continue;

		if (klp_is_thread_dead(t))

			continue;

		ret = check_task_calltrace(t, args, fn);

		if (ret)

			return ret;

arch/powerpc/kernel/livepatch.c

+2 −0
Original line number Diff line number Diff line
@@ -214,6 +214,8 @@ static int do_check_calltrace(struct walk_stackframe_args *args, 
	for_each_process_thread(g, t) {

		if (klp_is_migration_thread(t->comm))

			continue;

		if (klp_is_thread_dead(t))

			continue;

		ret = check_task_calltrace(t, args, fn);

		if (ret)

			return ret;

arch/x86/kernel/livepatch.c

+2 −0
Original line number Diff line number Diff line
@@ -184,6 +184,8 @@ static int do_check_calltrace(bool (*fn)(void *, int *, unsigned long), void *da 
	for_each_process_thread(g, t) {

		if (klp_is_migration_thread(t->comm))

			continue;

		if (klp_is_thread_dead(t))

			continue;



		ret = check_task_calltrace(t, fn, data);

		if (ret)

include/linux/livepatch.h

+12 −0
Original line number Diff line number Diff line
@@ -315,6 +315,18 @@ static inline bool klp_is_migration_thread(const char *task_name) 
			sizeof(KLP_MIGRATION_NAME_PREFIX) - 1);

}



/*

 * When the thread become zombie or dead, it's stack memory may have

 * been freed, we can not check calltrace for it.

 */

static inline bool klp_is_thread_dead(const struct task_struct *t)

{

	int exit_state = READ_ONCE(t->exit_state);



	return ((exit_state & EXIT_ZOMBIE) == EXIT_ZOMBIE) ||

		((exit_state & EXIT_DEAD) == EXIT_DEAD);

}



int klp_register_patch(struct klp_patch *patch);

int klp_unregister_patch(struct klp_patch *patch);

static inline int klp_module_coming(struct module *mod) { return 0; }