ffmpeg | branch: master | Matt Wolenetz <wolen...@chromium.org> | Fri Mar 2 15:12:41 2018 -0800| [133ddd38750acc01d0a9599d5b31375d33798d67] | committer: Michael Niedermayer
avformat/mov: Initialize a potential gap in ctts_data in mov_build_index mov_read_ctts ignores ctts entries having count <= 0. Generally, the aggregate of all ctts entries' count fields resulting from mov_read_ctts can be less than the corresponding sample_count. mov_build_index attempts to normalize any existing ctts_data counts to be 1, to make a 1-1 mapping of a ctts_data entry to a sample. That 1-1 mapping left a tail of uninitialized ctts_data entries when the aggregate, normalized ctts_count < sample_count. Even more generally, later usage of ctts_data may depend on the entire ctts_allocated_size having been initialized. This change memsets the entire allocation of the normalized ctts_data in mov_build_index, to prevent use of uninitialized data later. BUG=816787 Change-Id: I7fd7db255e3aeed076ee32c90cb2df211741c052 Reviewed-on: https://chromium-review.googlesource.com/947110 Reviewed-by: Xiaohan Wang <xhw...@chromium.org> Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=133ddd38750acc01d0a9599d5b31375d33798d67 --- libavformat/mov.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavformat/mov.c b/libavformat/mov.c index 00b3b25944..95b9cd3f8b 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -3747,6 +3747,9 @@ static void mov_build_index(MOVContext *mov, AVStream *st) av_free(ctts_data_old); return; } + + memset((uint8_t*)(sc->ctts_data), 0, sc->ctts_allocated_size); + for (i = 0; i < ctts_count_old && sc->ctts_count < sc->sample_count; i++) for (j = 0; j < ctts_data_old[i].count && _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
