ffmpeg | branch: release/1.2 | wm4 <nfx...@googlemail.com> | Mon Jan 5 04:45:26 2015 +0100| [931f4313b2ec2e47bb34b6906ec53df6d3d45f9a] | committer: Michael Niedermayer
avcodec/dvdsubdec: fix out of bounds accesses The code blindly trusted buffer offsets read from the file in the RLE decoder. Explicitly check the offset. Also error out on other RLE decoding errors. Signed-off-by: Michael Niedermayer <michae...@gmx.at> (cherry picked from commit c9151de7c42553bb145be608df8513c1287f1f24) Signed-off-by: Michael Niedermayer <michae...@gmx.at> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=931f4313b2ec2e47bb34b6906ec53df6d3d45f9a --- libavcodec/dvdsubdec.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/libavcodec/dvdsubdec.c b/libavcodec/dvdsubdec.c index cb268b8..2200633 100644 --- a/libavcodec/dvdsubdec.c +++ b/libavcodec/dvdsubdec.c @@ -99,6 +99,9 @@ static int decode_rle(uint8_t *bitmap, int linesize, int w, int h, int x, y, len, color; uint8_t *d; + if (start >= buf_size) + return -1; + bit_len = (buf_size - start) * 8; init_get_bits(&gb, buf + start, bit_len); @@ -340,10 +343,12 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header, sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect)); sub_header->num_rects = 1; sub_header->rects[0]->pict.data[0] = bitmap; - decode_rle(bitmap, w * 2, w, (h + 1) / 2, - buf, offset1, buf_size, is_8bit); - decode_rle(bitmap + w, w * 2, w, h / 2, - buf, offset2, buf_size, is_8bit); + if (decode_rle(bitmap, w * 2, w, (h + 1) / 2, + buf, offset1, buf_size, is_8bit) < 0) + goto fail; + if (decode_rle(bitmap + w, w * 2, w, h / 2, + buf, offset2, buf_size, is_8bit) < 0) + goto fail; sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE); if (is_8bit) { if (yuv_palette == 0) _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
