This is a note to let you know that I've just added the patch titled
fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fprobe-add-unlock-to-match-a-succeeded-ftrace_test_r.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9ea6b366f8d472e6814dbc9aad4e5bfb1d00ac39
Author: Ze Gao <zegao2021@xxxxxxxxx>
Date: Mon Jul 3 17:23:36 2023 +0800
fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock
[ Upstream commit 5f0c584daf7464f04114c65dd07269ee2bfedc13 ]
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@xxxxxxxxxxx/
Fixes: 3cc4e2c5fbae ("fprobe: make fprobe_kprobe_handler recursion free")
Reported-by: Yafang <laoar.shao@xxxxxxxxx>
Closes: https://lore.kernel.org/linux-trace-kernel/CALOAHbC6UpfFOOibdDiC7xFc5YFUgZnk3MZ=3Ny6we=AcrNbew@xxxxxxxxxxxxxx/
Signed-off-by: Ze Gao <zegao@xxxxxxxxxxx>
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Acked-by: Yafang Shao <laoar.shao@xxxxxxxxx>
Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 18d36842faf57..93b3e361bb97a 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);
}
