[FFmpeg-devel] MOV: fix crash when 'meta' occurs before first 'trak'

[Baptiste Coudurier]

Hi Alex,

On 3/2/2009 9:21 PM, Alex Converse wrote:
> Hi,
> 
> $subj.
> 
> An example of such a file is 12_metas.mp4 from the Amd. 24 conformance
> streams. [1]
> 
> Regards,
> Alex Converse
> 
> [1] http://standards.iso.org/ittf/PubliclyAvailableStandards/c046294_ISO_IEC_14496-4_2004_Amd_24_2008_Conformance_Testing.zip
> 
> 
> ------------------------------------------------------------------------
> 
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index b34326c..c9d5fdc 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -21,7 +21,8 @@
>  
>  #include <limits.h>
>  
> -//#define DEBUG
> +#define DEBUG
> +#undef NDEBUG
>  
>  #include "libavutil/intreadwrite.h"
>  #include "libavutil/avstring.h"

Forgotten hunk

> @@ -308,10 +309,12 @@ static int mov_read_dref(MOVContext *c, ByteIOContext *pb, MOVAtom atom)
>  
>  static int mov_read_hdlr(MOVContext *c, ByteIOContext *pb, MOVAtom atom)
>  {
> -    AVStream *st = c->fc->streams[c->fc->nb_streams-1];
> +    AVStream *st = NULL;
>      uint32_t type;
>      uint32_t ctype;
>  
> +    if (c->fc->nb_streams > 0)
> +        st = c->fc->streams[c->fc->nb_streams-1];
>      get_byte(pb); /* version */
>      get_be24(pb); /* flags */
>  
> @@ -325,6 +328,7 @@ static int mov_read_hdlr(MOVContext *c, ByteIOContext *pb, MOVAtom atom)
>              *((char *)&type), ((char *)&type)[1], ((char *)&type)[2], ((char *)&type)[3]);
>      if(!ctype)
>          c->isom = 1;
> +    if(st) {
>      if     (type == MKTAG('v','i','d','e'))
>          st->codec->codec_type = CODEC_TYPE_VIDEO;
>      else if(type == MKTAG('s','o','u','n'))
> @@ -334,6 +338,7 @@ static int mov_read_hdlr(MOVContext *c, ByteIOContext *pb, MOVAtom atom)
>      else if(type == MKTAG('s','u','b','p')) {
>          st->codec->codec_type = CODEC_TYPE_SUBTITLE;
>      }
> +    }
>      get_be32(pb); /* component  manufacture */
>      get_be32(pb); /* component flags */
>      get_be32(pb); /* component flags mask */
> 

Does

if (c->fc->nb_streams < 1) // meta before first trak
    return 0;

work ?

like in mov_read_extradata ? If so I prefer this.

-- 
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