diff options
author | Michael Niedermayer | 2019-09-09 20:05:09 +0200 |
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committer | Michael Niedermayer | 2019-10-02 14:49:04 +0200 |
commit | 9c84c162e9f9f000ef47d4fcd07354805f38d455 (patch) | |
tree | 0589f20f32f0fdb03032603e6b2a4b342c4ed7ee /libavcodec | |
parent | 9847380f5f5a3850ecc9f32fa310a7e5e3f703f7 (diff) |
avcodec/g2meet: Check if adjusted pixel was on the stack
This basically checks if a pixel that was coded with prediction
and residual could have been stored using a previous case.
This avoids basically a string of 0 symbols stored in less than
50 bytes to hit a O(n²) codepath.
Fixes: Timeout (too slow to wait -> immediately)
Fixes: 8668/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G2M_fuzzer-4895946310680576
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Diffstat (limited to 'libavcodec')
-rw-r--r-- | libavcodec/g2meet.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/libavcodec/g2meet.c b/libavcodec/g2meet.c index a1dec8d823..19e1c130ce 100644 --- a/libavcodec/g2meet.c +++ b/libavcodec/g2meet.c @@ -854,6 +854,9 @@ static int epic_decode_tile(ePICContext *dc, uint8_t *out, int tile_height, uint32_t ref_pix = curr_row[x - 1]; if (!x || !epic_decode_from_cache(dc, ref_pix, &pix)) { pix = epic_decode_pixel_pred(dc, x, y, curr_row, above_row); + if (is_pixel_on_stack(dc, pix)) + return AVERROR_INVALIDDATA; + if (x) { int ret = epic_add_pixel_to_cache(&dc->hash, ref_pix, |