1. ffmpeg
  2. Commit 5a1e0cae2f78b10cc7ab6cd41d6908c4ae89276f
Browse code

avformat/vividas: check for tiny blocks using alignment

Ask for a sample for these
Fixes: out of array access
Fixes: 16624/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5762455661182976

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 55d4e22d71ca75223ee61f7d2535fdc6e9991026)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Michael Niedermayer authored on 2019/09/01 06:20:01
Showing 1 changed files
libavformat/vividas.c
History View file @ 5a1e0ca
... ... 
@@ -153,6 +153,10 @@ static void decode_block(uint8_t *src, uint8_t *dest, unsigned size,
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     if (align) {
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         uint32_t tmpkey = *key_ptr - key;
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+        if (a2 > s) {
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+            a2 = s;
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+            avpriv_request_sample(NULL, "tiny aligned block\n");
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+        }
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         memcpy(tmp + align, src, a2);
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         xor_block(tmp, tmp, 4, key, &tmpkey);
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         memcpy(dest, tmp + align, a2);