[FFmpeg-devel] [PATCH] avformat/hlsenc: Check that data is set

[Steven Liu]

> 在 2018年1月20日，上午10:35，Jeyapal, Karthick <kjeyapal at akamai.com> 写道：
> 
> 
> 
>> On 1/20/18 6:29 AM, Brendan McGrath wrote:
>> If codecpar->extradata is not set (for example, when the stream goes
>> through the 'tee' muxer), then a segfault occurs.
>> 
>> This patch ensures the data variable is not null before attempting
>> to access it
>> 
>> Signed-off-by: Brendan McGrath <redmcg at redmandi.dyndns.org>
>> ---
>> Before the var_stream_map option was available - I was using the tee
>> muxer to create each resolution as an individual stream.
>> 
>> When running this configuration after the most recent hlsenc change
>> I hit a segfault
>> 
>> The most simple command which recreates the segfault is:
>> ffmpeg -i in.ts -map 0:a -map 0:v -c:a aac -c:v h264 \
>>  -f tee [select=\'a,v\':f=hls]tv_hls_hd.m3u8
>> 
>> libavformat/hlsenc.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
>> index 8ad906a..42e437f 100644
>> --- a/libavformat/hlsenc.c
>> +++ b/libavformat/hlsenc.c
>> @@ -308,7 +308,7 @@ static void write_codec_attr(AVStream *st, VariantStream *vs) {
>> 
>>     if (st->codecpar->codec_id == AV_CODEC_ID_H264) {
>>         uint8_t *data = st->codecpar->extradata;
>> -        if ((data[0] | data[1] | data[2]) == 0 && data[3] == 1 && (data[4] & 0x1F) == 7) {
>> +        if (data && (data[0] | data[1] | data[2]) == 0 && data[3] == 1 && (data[4] & 0x1F) == 7) {
>>             snprintf(attr, sizeof(attr),
>>                      "avc1.%02x%02x%02x", data[5], data[6], data[7]);
>>         } else {
> 
> LGTM. Thanks for the fix

will apply