tracing/fprobe: Fix to check whether fprobe is registered correctly

Since commit ab51e15d53 ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
for fprobe") introduced fprobe_kprobe_handler() for fprobe::ops::func,
unregister_fprobe() fails to unregister the registered if user specifies
FPROBE_FL_KPROBE_SHARED flag.
Moreover, __register_ftrace_function() is possible to change the
ftrace_ops::func, thus we have to check fprobe::ops::saved_func instead.

To check it correctly, it should confirm the fprobe::ops::saved_func is
either fprobe_handler() or fprobe_kprobe_handler().

Link: https://lore.kernel.org/all/166677683946.1459107.15997653945538644683.stgit@devnote3/

Fixes: cad9931f64 ("fprobe: Add ftrace based probe APIs")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This commit is contained in:
Masami Hiramatsu (Google) 2022-10-23 11:11:43 +09:00
parent d05ea35e7e
commit 61b304b73a

View file

@ -303,7 +303,8 @@ int unregister_fprobe(struct fprobe *fp)
{
int ret;
if (!fp || fp->ops.func != fprobe_handler)
if (!fp || (fp->ops.saved_func != fprobe_handler &&
fp->ops.saved_func != fprobe_kprobe_handler))
return -EINVAL;
/*