On Fri, 9 Aug 2024, Dan Carpenter wrote:
> If the "tool->data" allocation fails then there is no need to call
> osnoise_free_top() and, in fact, doing so will lead to a NULL dereference.
>
> Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> tools/tracing/rtla/src/osnoise_top.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
> index f594a44df840..2f756628613d 100644
> --- a/tools/tracing/rtla/src/osnoise_top.c
> +++ b/tools/tracing/rtla/src/osnoise_top.c
> @@ -651,8 +651,10 @@ struct osnoise_tool *osnoise_init_top(struct osnoise_top_params *params)
> return NULL;
>
> tool->data = osnoise_alloc_top(nr_cpus);
> - if (!tool->data)
> - goto out_err;
> + if (!tool->data) {
> + osnoise_destroy_tool(tool);
> + return NULL;
> + }
>
> tool->params = params;
>
> @@ -660,11 +662,6 @@ struct osnoise_tool *osnoise_init_top(struct osnoise_top_params *params)
> osnoise_top_handler, NULL);
>
> return tool;
> -
> -out_err:
> - osnoise_free_top(tool->data);
> - osnoise_destroy_tool(tool);
> - return NULL;
> }
>
> static int stop_tracing;
> --
Although your fix appears to be correct, I wonder if it would be better to
create a second error label, such as out_destroy_tool: as described in
section 7 of the coding-style.rst
Thanks
John Kacur
