James Almer: > On 8/9/2023 7:08 AM, Nicolas George wrote: >> Andreas Rheinhardt (12023-08-06): >>> The AVBPrint API guarantees that the string buffer is always >>> zero-terminated; in order to honour this guarantee, there >>> obviously must be a string buffer at all and it must have >>> a size >= 1. Therefore av_bprint_init_for_buffer() treats >>> passing a NULL buffer or size == 0 as invalid data that >>> leads to undefined behaviour, namely NPD in case NULL is provided >>> or a write to a buffer of size 0 in case size == 0. >>> >>> But it would be easy to support this, namely by using the internal >>> buffer with AV_BPRINT_SIZE_COUNT_ONLY in case size == 0. >>> >>> There is a reason to allow this: Several functions like >>> av_channel_(description|name) are actually wrappers >>> around corresponding AVBPrint functions. They accept user >>> provided buffers and are supposed to return the required >>> size of the buffer, which would allow the user to call >>> it once to get the required buffer size and call it once >>> more after having allocated the buffer. >>> If av_bprint_init_for_buffer() treats size == 0 as invalid, >>> all these users would need to check for this themselves >>> and basically add the same codeblock that this patch >>> adds to av_bprint_init_for_buffer(). >>> >>> This change is in line with e.g. snprintf() which also allows >>> the pointer to be NULL in case size is zero. >>> >>> This fixes Coverity issues #1503074, #1503076 and #1503082; >>> all of these issues are about providing NULL to the channel-layout >>> functions that are wrappers around AVBPrint versions. >>> >>> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@outlook.com> >>> --- >>> Missing lavu minor version bump. >> >> Looks good to me. >> >> The other patches in the series too, but I do not maintain the channel >> layouts. >> >> Regards, > > The layout patches are ok too.
Ok, then I'll already apply them tomorrow. Thanks for the reviews. - Andreas _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
