[FFmpeg-devel] [PATCH] avfilter/af_pan: fix null pointer dereference on empty token

Marton Balint cus at passwd.hu
Mon Feb 6 00:01:03 EET 2017


On Sun, 5 Feb 2017, Nicolas George wrote:

> Le septidi 17 pluviôse, an CCXXV, Marton Balint a écrit :
>> Fixes Coverity CID 1396254.
>>
>> Signed-off-by: Marton Balint <cus at passwd.hu>
>> ---
>>  libavfilter/af_pan.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/libavfilter/af_pan.c b/libavfilter/af_pan.c
>> index 94f1587..00eef2b 100644
>> --- a/libavfilter/af_pan.c
>> +++ b/libavfilter/af_pan.c
>> @@ -115,6 +115,11 @@ static av_cold int init(AVFilterContext *ctx)
>>      if (!args)
>>          return AVERROR(ENOMEM);
>>      arg = av_strtok(args, "|", &tokenizer);
>
>> +    if (!arg) {
>> +        av_log(ctx, AV_LOG_ERROR, "Cannot tokenize argument\n");
>> +        ret = AVERROR(EINVAL);
>> +        goto fail;
>> +    }
>
> Thanks for catching this. The fix seems correct. The error message, on
> the other hand, is not good: it is meant for users but does not tell
> them anything.
>
> If I read the code correctly, this can only be triggered if the argument
> to pan contains only the delimiter character. Something like "channel
> layout not specified" would be more useful.
>

Well, Coverity found it, I only fixed it :)

Pushed with the proposed error message.

Thanks,
Marton


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