From 12245ab1f677074b8ff83e87f76a41aba692ccd6 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 14 Jun 2017 23:55:17 +0200 Subject: [PATCH] avcodec/mpeg4videodec: Check sprite delta upshift against overflowing. Fixes: runtime error: signed integer overflow: -268386304 * 16 cannot be represented in type 'int' Fixes: 2204/clusterfuzz-testcase-minimized-5616756909408256 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mpeg4videodec.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 3edf266580..99680dabc3 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -361,14 +361,16 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g int shift_y = 16 - ctx->sprite_shift[0]; int shift_c = 16 - ctx->sprite_shift[1]; - if (shift_c < 0 || shift_y < 0 || - FFABS(sprite_offset[0][0]) >= INT_MAX >> shift_y || - FFABS(sprite_offset[1][0]) >= INT_MAX >> shift_c || - FFABS(sprite_offset[0][1]) >= INT_MAX >> shift_y || - FFABS(sprite_offset[1][1]) >= INT_MAX >> shift_c - ) { - avpriv_request_sample(s->avctx, "Too large sprite shift or offset"); - goto overflow; + for (i = 0; i < 2; i++) { + if (shift_c < 0 || shift_y < 0 || + FFABS( sprite_offset[0][i]) >= INT_MAX >> shift_y || + FFABS( sprite_offset[1][i]) >= INT_MAX >> shift_c || + FFABS(s->sprite_delta[0][i]) >= INT_MAX >> shift_y || + FFABS(s->sprite_delta[1][i]) >= INT_MAX >> shift_y + ) { + avpriv_request_sample(s->avctx, "Too large sprite shift, delta or offset"); + goto overflow; + } } for (i = 0; i < 2; i++) {