From c20f4fcb74da2d0432c7b54499bb98f48236b904 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Mon, 9 Oct 2017 11:49:28 +0200
Subject: [PATCH] avcodec/ffv1dec: Fix out of array read in slice counting
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Fixes: test-201710.mp4
Found-by: 连一汉 <lianyihan@360.cn> and Zhibin Hu
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavcodec/ffv1dec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index d2bfee784fb..5eadb6b1586 100644
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -717,7 +717,7 @@ static int read_header(FFV1Context *f)
} else {
const uint8_t *p = c->bytestream_end;
for (f->slice_count = 0;
- f->slice_count < MAX_SLICES && 3 < p - c->bytestream_start;
+ f->slice_count < MAX_SLICES && 3 + 5*!!f->ec < p - c->bytestream_start;
f->slice_count++) {
int trailer = 3 + 5*!!f->ec;
int size = AV_RB24(p-trailer);
--
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