Re: [PATCH] rtla/osnoise_hist: avoid NULL pointer dereference on out

[Daniel Bristot de Oliveira <bristot@kernel.org>]

On 3/30/22 09:13, Haowen Bai wrote:
> record is NULL and go out but dereference record->trace.
> 
> report by coccicheck:
> tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR:
> record is NULL but dereferenced.

Duplicated of:
https://lore.kernel.org/lkml/20220322113253.57390-1-wanjiabing@vivo.com/

Next time, please, consolidate your patches for the same Fixes: into a single one.

Thanks,
-- Daniel

> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> ---
>  tools/tracing/rtla/src/osnoise_hist.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
> index b4380d4..b7862b4 100644
> --- a/tools/tracing/rtla/src/osnoise_hist.c
> +++ b/tools/tracing/rtla/src/osnoise_hist.c
> @@ -819,13 +819,13 @@ int osnoise_hist_main(int argc, char *argv[])
>  		record = osnoise_init_trace_tool("osnoise");
>  		if (!record) {
>  			err_msg("Failed to enable the trace instance\n");
> -			goto out_hist;
> +			goto out_top;
>  		}
>  
>  		if (params->events) {
>  			retval = trace_events_enable(&record->trace, params->events);
>  			if (retval)
> -				goto out_hist;
> +				goto out_top;
>  		}
>  
>  		trace_instance_start(&record->trace);
> @@ -845,7 +845,7 @@ int osnoise_hist_main(int argc, char *argv[])
>  						    trace);
>  		if (retval < 0) {
>  			err_msg("Error iterating on events\n");
> -			goto out_hist;
> +			goto out_top;
>  		}
>  
>  		if (trace_is_off(&tool->trace, &record->trace))
> @@ -865,9 +865,9 @@ int osnoise_hist_main(int argc, char *argv[])
>  			save_trace_to_file(record->trace.inst, params->trace_output);
>  		}
>  	}
> -
> -out_hist:
> +out_top:
>  	trace_events_destroy(&record->trace, params->events);
> +out_hist:
>  	params->events = NULL;
>  	osnoise_free_histogram(tool->data);
>  out_destroy: