kernel/trace: Initialize integer variable to prevent garbage return value

[PATCH] kernel/trace: Initialize integer variable to prevent garbage return value

Posted by Gautam Menghani 3 years, 10 months ago

Initialize the integer variable to 0 to fix the clang scan warning:
Undefined or garbage value returned to caller 
[core.uninitialized.UndefReturn]
        return ret;

Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
---
 kernel/trace/trace_boot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 0580287d7a0d..778200dd8ede 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -300,7 +300,7 @@ trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
 {
 	struct xbc_node *node;
 	const char *p, *handler;
-	int ret;
+	int ret = 0;
 
 	handler = xbc_node_get_data(hnode);
 
-- 
2.25.1

Re: [PATCH] kernel/trace: Initialize integer variable to prevent garbage return value

Posted by Steven Rostedt 3 years, 10 months ago

On Sat, 21 May 2022 23:18:26 -0700
Gautam Menghani <gautammenghani201@gmail.com> wrote:

> Initialize the integer variable to 0 to fix the clang scan warning:
> Undefined or garbage value returned to caller 
> [core.uninitialized.UndefReturn]
>         return ret;
> 
> Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
> ---
>  kernel/trace/trace_boot.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
> index 0580287d7a0d..778200dd8ede 100644
> --- a/kernel/trace/trace_boot.c
> +++ b/kernel/trace/trace_boot.c
> @@ -300,7 +300,7 @@ trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
>  {
>  	struct xbc_node *node;
>  	const char *p, *handler;
> -	int ret;
> +	int ret = 0;

Looks good to me. Masami, care to ack it?

-- Steve

>  
>  	handler = xbc_node_get_data(hnode);
>

Re: [PATCH] kernel/trace: Initialize integer variable to prevent garbage return value

Posted by Masami Hiramatsu (Google) 3 years, 10 months ago

On Wed, 25 May 2022 11:25:51 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Sat, 21 May 2022 23:18:26 -0700
> Gautam Menghani <gautammenghani201@gmail.com> wrote:
> 
> > Initialize the integer variable to 0 to fix the clang scan warning:
> > Undefined or garbage value returned to caller 
> > [core.uninitialized.UndefReturn]
> >         return ret;
> > 
> > Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
> > ---
> >  kernel/trace/trace_boot.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
> > index 0580287d7a0d..778200dd8ede 100644
> > --- a/kernel/trace/trace_boot.c
> > +++ b/kernel/trace/trace_boot.c
> > @@ -300,7 +300,7 @@ trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
> >  {
> >  	struct xbc_node *node;
> >  	const char *p, *handler;
> > -	int ret;
> > +	int ret = 0;
> 
> Looks good to me. Masami, care to ack it?

Thanks! This looks good to me.

Fixes: 8993665abcce ("tracing/boot: Support multiple handlers for per-event histogram")
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you!

> 
> -- Steve
> 
> >  
> >  	handler = xbc_node_get_data(hnode);
> >  
> 


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