From 247a1de7f7d9c5628cf188e677d10ce9e12bd2f2 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 15 Jun 2019 00:47:06 +0200 Subject: [PATCH] avcodec/videodsp_template: Fix overflow of addition Fixes: addition of unsigned offset to 0x7f56fc26a9b6 overflowed to 0x7f56fc26a8be* Fixes: clusterfuzz-testcase-minimized-mediasource_MP4_AVC1_pipeline_integration_fuzzer-4917949056679936 Reported-by: Matt Wolenetz Reviewed-by: Matt Wolenetz Signed-off-by: Michael Niedermayer --- libavcodec/videodsp_template.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavcodec/videodsp_template.c b/libavcodec/videodsp_template.c index 94c1b7188d..55123a5844 100644 --- a/libavcodec/videodsp_template.c +++ b/libavcodec/videodsp_template.c @@ -44,7 +44,8 @@ void FUNC(ff_emulated_edge_mc)(uint8_t *buf, const uint8_t *src, src_y = 1 - block_h; } if (src_x >= w) { - src += (w - 1 - src_x) * sizeof(pixel); + // The subtracted expression has an unsigned type and must thus not be negative + src -= (1 + src_x - w) * sizeof(pixel); src_x = w - 1; } else if (src_x <= -block_w) { src += (1 - block_w - src_x) * sizeof(pixel);