tracing: Fix wrong return in kprobe_event_gen_test.c

[PATCH] tracing: Fix wrong return in kprobe_event_gen_test.c

Posted by Anton Gusev 2 years, 7 months ago

Overwriting the error code with the deletion result may cause the
function to return 0 despite encountering an error. Commit b111545d26c0
("tracing: Remove the useless value assignment in
test_create_synth_event()") solves a similar issue by
returning the original error code, so this patch does the same.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Anton Gusev <aagusev@ispras.ru>
---
 kernel/trace/kprobe_event_gen_test.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c
index c736487fc0e4..e0c420eb0b2b 100644
--- a/kernel/trace/kprobe_event_gen_test.c
+++ b/kernel/trace/kprobe_event_gen_test.c
@@ -146,7 +146,7 @@ static int __init test_gen_kprobe_cmd(void)
 	if (trace_event_file_is_valid(gen_kprobe_test))
 		gen_kprobe_test = NULL;
 	/* We got an error after creating the event, delete it */
-	ret = kprobe_event_delete("gen_kprobe_test");
+	kprobe_event_delete("gen_kprobe_test");
 	goto out;
 }
 
@@ -211,7 +211,7 @@ static int __init test_gen_kretprobe_cmd(void)
 	if (trace_event_file_is_valid(gen_kretprobe_test))
 		gen_kretprobe_test = NULL;
 	/* We got an error after creating the event, delete it */
-	ret = kprobe_event_delete("gen_kretprobe_test");
+	kprobe_event_delete("gen_kretprobe_test");
 	goto out;
 }
 
-- 
2.39.1

Re: [PATCH] tracing: Fix wrong return in kprobe_event_gen_test.c

Posted by Masami Hiramatsu (Google) 2 years, 7 months ago

On Tue, 31 Jan 2023 10:58:18 +0300
Anton Gusev <aagusev@ispras.ru> wrote:

> Overwriting the error code with the deletion result may cause the
> function to return 0 despite encountering an error. Commit b111545d26c0
> ("tracing: Remove the useless value assignment in
> test_create_synth_event()") solves a similar issue by
> returning the original error code, so this patch does the same.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Anton Gusev <aagusev@ispras.ru>

Oops, thanks for the fix!

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

> ---
>  kernel/trace/kprobe_event_gen_test.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c
> index c736487fc0e4..e0c420eb0b2b 100644
> --- a/kernel/trace/kprobe_event_gen_test.c
> +++ b/kernel/trace/kprobe_event_gen_test.c
> @@ -146,7 +146,7 @@ static int __init test_gen_kprobe_cmd(void)
>  	if (trace_event_file_is_valid(gen_kprobe_test))
>  		gen_kprobe_test = NULL;
>  	/* We got an error after creating the event, delete it */
> -	ret = kprobe_event_delete("gen_kprobe_test");
> +	kprobe_event_delete("gen_kprobe_test");
>  	goto out;
>  }
>  
> @@ -211,7 +211,7 @@ static int __init test_gen_kretprobe_cmd(void)
>  	if (trace_event_file_is_valid(gen_kretprobe_test))
>  		gen_kretprobe_test = NULL;
>  	/* We got an error after creating the event, delete it */
> -	ret = kprobe_event_delete("gen_kretprobe_test");
> +	kprobe_event_delete("gen_kretprobe_test");
>  	goto out;
>  }
>  
> -- 
> 2.39.1
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>

Re: [PATCH] tracing: Fix wrong return in kprobe_event_gen_test.c

Posted by Steven Rostedt 2 years, 7 months ago

On Tue, 31 Jan 2023 10:58:18 +0300
Anton Gusev <aagusev@ispras.ru> wrote:

> Overwriting the error code with the deletion result may cause the
> function to return 0 despite encountering an error. Commit b111545d26c0
> ("tracing: Remove the useless value assignment in
> test_create_synth_event()") solves a similar issue by
> returning the original error code, so this patch does the same.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Anton Gusev <aagusev@ispras.ru>

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Thanks Anton!

-- Steve