From 5f0c584daf7464f04114c65dd07269ee2bfedc13 Mon Sep 17 00:00:00 2001
From: Ze Gao <zegao2021@gmail.com>
Date: Mon, 3 Jul 2023 17:23:36 +0800
Subject: [PATCH] fprobe: add unlock to match a succeeded
ftrace_test_recursion_trylock
Unlock ftrace recursion lock when fprobe_kprobe_handler() is failed
because of some running kprobe.
Link: https://lore.kernel.org/all/20230703092336.268371-1-zegao@tencent.com/
Fixes: 3cc4e2c5fbae ("fprobe: make fprobe_kprobe_handler recursion free")
Reported-by: Yafang <laoar.shao@gmail.com>
Closes: https://lore.kernel.org/linux-trace-kernel/CALOAHbC6UpfFOOibdDiC7xFc5YFUgZnk3MZ=3Ny6we=AcrNbew@mail.gmail.com/
Signed-off-by: Ze Gao <zegao@tencent.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
kernel/trace/fprobe.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 0121e8c0d54e7..58e4b3607aefe 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -102,12 +102,14 @@ static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip,
if (unlikely(kprobe_running())) {
fp->nmissed++;
- return;
+ goto recursion_unlock;
}
kprobe_busy_begin();
__fprobe_handler(ip, parent_ip, ops, fregs);
kprobe_busy_end();
+
+recursion_unlock:
ftrace_test_recursion_unlock(bit);
}
--
2.30.2