[PATCH weston 2/3] screenshooter: fix various memory handling

[Derek Foreman]

On 05/12/14 06:49 AM, Marek Chalupa wrote:
> There were unchecked malloc and free of conditionally allocated
> memory without checking if the memory was really allocated.
> Also simplify error handling in one function.
> 
> Signed-off-by: Marek Chalupa <mchqwerty at gmail.com>
> ---
>  src/screenshooter.c | 27 +++++++++++++++++++--------
>  1 file changed, 19 insertions(+), 8 deletions(-)
> 
> diff --git a/src/screenshooter.c b/src/screenshooter.c
> index 6246cda..b7b1fd0 100644
> --- a/src/screenshooter.c
> +++ b/src/screenshooter.c
> @@ -464,8 +464,11 @@ weston_recorder_free(struct weston_recorder *recorder)
>  {
>  	if (recorder == NULL)
>  		return;
> +
> +	if (recorder->tmpbuf)
> +		free(recorder->tmpbuf);
> +
>  	free(recorder->rect);
> -	free(recorder->tmpbuf);

I think recorder->tmpbuf should be NULL if it was never required
(recorder is allocated with zalloc), and free(NULL); is a NOP...

>  	free(recorder->frame);
>  	free(recorder);
>  }
> @@ -495,12 +498,16 @@ weston_recorder_create(struct weston_output *output, const char *filename)
>  
>  	if ((recorder->frame == NULL) || (recorder->rect == NULL)) {
>  		weston_log("%s: out of memory\n", __func__);
> -		weston_recorder_free(recorder);
> -		return;
> +		goto err_recorder;
>  	}
>  
> -	if (!do_yflip)
> +	if (!do_yflip) {
>  		recorder->tmpbuf = malloc(size);
> +		if (recorder->tmpbuf == NULL) {
> +			weston_log("%s: out of memory\n", __func__);
> +			goto err_recorder;
> +		}

Yup, we need this bit.

And I like the goto err_recorder stuff as well, though I guess that's a
matter of preference.

> +	}
>  
>  	header.magic = WCAP_HEADER_MAGIC;
>  
> @@ -514,8 +521,7 @@ weston_recorder_create(struct weston_output *output, const char *filename)
>  		break;
>  	default:
>  		weston_log("unknown recorder format\n");
> -		weston_recorder_free(recorder);
> -		return;
> +		goto err_recorder;
>  	}
>  
>  	recorder->fd = open(filename,
> @@ -523,8 +529,7 @@ weston_recorder_create(struct weston_output *output, const char *filename)
>  
>  	if (recorder->fd < 0) {
>  		weston_log("problem opening output file %s: %m\n", filename);
> -		weston_recorder_free(recorder);
> -		return;
> +		goto err_recorder;
>  	}
>  
>  	header.width = output->current_mode->width;
> @@ -535,6 +540,12 @@ weston_recorder_create(struct weston_output *output, const char *filename)
>  	wl_signal_add(&output->frame_signal, &recorder->frame_listener);
>  	output->disable_planes++;
>  	weston_output_damage(output);
> +
> +	return;
> +
> +err_recorder:
> +	weston_recorder_free(recorder);
> +	return;
>  }
>  
>  static void
>