ffmpeg | branch: master | Michael Niedermayer <michae...@gmx.at> | Fri Oct 3 20:15:52 2014 +0200| [0b39ac6f54505a538c21fe49a626de94c518c903] | committer: Anton Khirnov
gifdec: refactor interleave end handling Fixes invalid writes with very small image heights. CC: libav-sta...@libav.org Bug-ID: CVE-2014-8547 Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind Signed-off-by: Anton Khirnov <an...@khirnov.net> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0b39ac6f54505a538c21fe49a626de94c518c903 --- libavcodec/gifdec.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/libavcodec/gifdec.c b/libavcodec/gifdec.c index cdb7f23..df5ab78 100644 --- a/libavcodec/gifdec.c +++ b/libavcodec/gifdec.c @@ -125,26 +125,21 @@ static int gif_read_image(GifState *s, AVFrame *frame) case 1: y1 += 8; ptr += linesize * 8; - if (y1 >= height) { - y1 = pass ? 2 : 4; - ptr = ptr1 + linesize * y1; - pass++; - } break; case 2: y1 += 4; ptr += linesize * 4; - if (y1 >= height) { - y1 = 1; - ptr = ptr1 + linesize; - pass++; - } break; case 3: y1 += 2; ptr += linesize * 2; break; } + while (y1 >= height) { + y1 = 4 >> pass; + ptr = ptr1 + linesize * y1; + pass++; + } } else { ptr += linesize; } _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
