This patch replaces preempt_{disable, enable} with its corresponding
notrace version in rethook_trampoline_handler so no worries about stack
recursion or overflow introduced by preempt_count_{add, sub} under
fprobe + rethook context.
Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook")
Signed-off-by: Ze Gao <zegao@xxxxxxxxxxx>
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
---
kernel/trace/rethook.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c
index 32c3dfdb4d6a..60f6cb2b486b 100644
--- a/kernel/trace/rethook.c
+++ b/kernel/trace/rethook.c
@@ -288,7 +288,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs,
* These loops must be protected from rethook_free_rcu() because those
* are accessing 'rhn->rethook'.
*/
- preempt_disable();
+ preempt_disable_notrace();
/*
* Run the handler on the shadow stack. Do not unlink the list here because
@@ -321,7 +321,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs,
first = first->next;
rethook_recycle(rhn);
}
- preempt_enable();
+ preempt_enable_notrace();
return correct_ret_addr;
}
--
2.40.1
