[FFmpeg-devel] [PATCH 10/11] avcodec/h264_parser: zero-initialize H264PredWeightTable

[Mark Thompson]

On 11/06/17 15:07, Timo Rothenpieler wrote:
> Fixes CID 1404889
> ---
>  libavcodec/h264_parser.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c
> index 2564c6c6c3..1a304f318f 100644
> --- a/libavcodec/h264_parser.c
> +++ b/libavcodec/h264_parser.c
> @@ -155,7 +155,7 @@ found:
>  static int scan_mmco_reset(AVCodecParserContext *s, GetBitContext *gb,
>                             void *logctx)
>  {
> -    H264PredWeightTable pwt;
> +    H264PredWeightTable pwt = { 0 };
>      int slice_type_nos = s->pict_type & 3;
>      H264ParseContext *p = s->priv_data;
>      int list_count, ref_count[2];
> 

Seems dubious?  That is not a small structure, and it's being used essentially write-only here to skip over an unwanted part of the slice header - since it will only ever write to a small proportion of the elements, initialising all of them to zero feels like a waste.

(The only argument in Coverity seems to be that passing a pointer to an uninitialised structure to an external function is bad - it hasn't actually looked at the function to observe that it doesn't read anything currently in the structure.)