From 936ca7f1012ebb52233cc0a5acad3febfdbe9ec3 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 28 Jun 2019 20:38:56 +0200 Subject: [PATCH] avcodec/sanm: Optimize fill_frame() with av_memcpy_backptr() Fixes: Timeout (76 sec -> 24 sec) Fixes: 15043/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SANM_fuzzer-5699856238116864 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/sanm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/libavcodec/sanm.c b/libavcodec/sanm.c index 811fd2188e..25aee7220f 100644 --- a/libavcodec/sanm.c +++ b/libavcodec/sanm.c @@ -1358,8 +1358,10 @@ static int read_frame_header(SANMVideoContext *ctx, SANMFrameHeader *hdr) static void fill_frame(uint16_t *pbuf, int buf_size, uint16_t color) { - while (buf_size--) + if (buf_size--) { *pbuf++ = color; + av_memcpy_backptr((uint8_t*)pbuf, 2, 2*buf_size); + } } static int copy_output(SANMVideoContext *ctx, SANMFrameHeader *hdr)