From dbac849c4db9c9378ab6e55f4f489debf2659b04 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Mon, 13 Aug 2018 00:19:55 +0200
Subject: [PATCH] avcodec/lagarith: Optimize FRAME_SOLID_RGBA
Changes 5466110 decicycles to 1798072 decicycles (tested with fate-suite/lagarith/lag-rgb32.avi)
Fixes: Timeout
Fixes: 9484/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LAGARITH_fuzzer-5707859156271104
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavcodec/lagarith.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/libavcodec/lagarith.c b/libavcodec/lagarith.c
index 510a6ff2d6a..3d3b4d41f43 100644
--- a/libavcodec/lagarith.c
+++ b/libavcodec/lagarith.c
@@ -572,8 +572,14 @@ static int lag_decode_frame(AVCodecContext *avctx,
dst = p->data[0];
if (frametype == FRAME_SOLID_RGBA) {
+ int qwidth = avctx->width>>2;
+ uint64_t c = ((uint64_t)offset_gu << 32) | offset_gu;
for (j = 0; j < avctx->height; j++) {
- for (i = 0; i < avctx->width; i++)
+ for (i = 0; i < qwidth; i++) {
+ AV_WN64(dst + i * 16 , c);
+ AV_WN64(dst + i * 16 + 8, c);
+ }
+ for (i = 4*qwidth; i < avctx->width; i++)
AV_WN32(dst + i * 4, offset_gu);
dst += p->linesize[0];
}
--
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