From 5443c4bdf4828ac5b7b19cf54feb496c2da40079 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 20 Jun 2017 13:52:06 +0200 Subject: [PATCH] avcodec/mpeg4videodec: Fix overflow in virtual_ref computation Fixes: runtime error: signed integer overflow: 262144 * -16120 cannot be represented in type 'int' Fixes: 2292/clusterfuzz-testcase-minimized-6156080415506432 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mpeg4videodec.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 99680dabc3..d2f22dd372 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -243,18 +243,18 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g * from w&h based to w2&h2 based which are of the 2^x form. */ virtual_ref[0][0] = 16 * (vop_ref[0][0] + w2) + ROUNDED_DIV(((w - w2) * - (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) + - w2 * (r * sprite_ref[1][0] - 16 * vop_ref[1][0])), w); + (r * sprite_ref[0][0] - 16LL * vop_ref[0][0]) + + w2 * (r * sprite_ref[1][0] - 16LL * vop_ref[1][0])), w); virtual_ref[0][1] = 16 * vop_ref[0][1] + ROUNDED_DIV(((w - w2) * - (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) + - w2 * (r * sprite_ref[1][1] - 16 * vop_ref[1][1])), w); + (r * sprite_ref[0][1] - 16LL * vop_ref[0][1]) + + w2 * (r * sprite_ref[1][1] - 16LL * vop_ref[1][1])), w); virtual_ref[1][0] = 16 * vop_ref[0][0] + - ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) + - h2 * (r * sprite_ref[2][0] - 16 * vop_ref[2][0])), h); + ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][0] - 16LL * vop_ref[0][0]) + + h2 * (r * sprite_ref[2][0] - 16LL * vop_ref[2][0])), h); virtual_ref[1][1] = 16 * (vop_ref[0][1] + h2) + - ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) + - h2 * (r * sprite_ref[2][1] - 16 * vop_ref[2][1])), h); + ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][1] - 16LL * vop_ref[0][1]) + + h2 * (r * sprite_ref[2][1] - 16LL * vop_ref[2][1])), h); switch (ctx->num_sprite_warping_points) { case 0: