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authorPetr Mladek <pmladek@suse.cz>2015-02-18 18:02:13 +0100
committerJiri Kosina <jkosina@suse.cz>2015-02-22 23:02:56 +0100
commitc4ce0da8ec62d83c96e29db7dadd6d3985344bb3 (patch)
tree1e7f1cc23c34e21a0238926df348a1d22f4f0cca /kernel/livepatch/core.c
parente0b561ee78d82a4cc7792aa28fa4b1ea15325dcc (diff)
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livepatch: RCU protect struct klp_func all the time when used in klp_ftrace_handler()
func->new_func has been accessed after rcu_read_unlock() in klp_ftrace_handler() and therefore the access was not protected. Signed-off-by: Petr Mladek <pmladek@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'kernel/livepatch/core.c')
-rw-r--r--kernel/livepatch/core.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 69bf3aa3bde8..782172f073c5 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -314,12 +314,12 @@ static void notrace klp_ftrace_handler(unsigned long ip,
rcu_read_lock();
func = list_first_or_null_rcu(&ops->func_stack, struct klp_func,
stack_node);
- rcu_read_unlock();
-
if (WARN_ON_ONCE(!func))
- return;
+ goto unlock;
klp_arch_set_pc(regs, (unsigned long)func->new_func);
+unlock:
+ rcu_read_unlock();
}
static int klp_disable_func(struct klp_func *func)