diff mbox series

[v2] tracing/fprobe: Fix to check whether fprobe is registered correctly

Message ID 166677683946.1459107.15997653945538644683.stgit@devnote3 (mailing list archive)
State Accepted
Headers show
Series [v2] tracing/fprobe: Fix to check whether fprobe is registered correctly | expand

Commit Message

Masami Hiramatsu (Google) Oct. 26, 2022, 9:33 a.m. UTC 
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Since commit ab51e15d535e ("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().

Fixes: cad9931f64dc ("fprobe: Add ftrace based probe APIs")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 kernel/trace/fprobe.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 71614b2a67ff..e8143e368074 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -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;
 
 	/*