path: root/user/ffmpeg/CVE-2019-13312.patch

From ea56af88956061d700043c5c4b026ac57834b0c8 Mon Sep 17 00:00:00 2001
From: Carl Eugen Hoyos <ceffmpeg@gmail.com>
Date: Mon, 1 Jul 2019 01:45:36 +0200
Subject: [PATCH] lavc/zmbvenc: Do not left-shift negative values.

Fixes the following ubsan errors with the sample from ticket #7980:
libavcodec/zmbvenc.c:243:29: runtime error: left shift of negative value -4
libavcodec/zmbvenc.c:244:28: runtime error: left shift of negative value -2
---
 libavcodec/zmbvenc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/zmbvenc.c b/libavcodec/zmbvenc.c
index 4887175..0e22ce6 100644
--- a/libavcodec/zmbvenc.c
+++ b/libavcodec/zmbvenc.c
@@ -240,8 +240,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
                 tprev = prev + x * c->bypp;
 
                 zmbv_me(c, tsrc, p->linesize[0], tprev, c->pstride, x, y, &mx, &my, &xored);
-                mv[0] = (mx << 1) | !!xored;
-                mv[1] = my << 1;
+                mv[0] = (mx * 2) | !!xored;
+                mv[1] = my * 2;
                 tprev += mx * c->bypp + my * c->pstride;
                 if(xored){
                     for(j = 0; j < bh2; j++){
-- 
2.7.4