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| author | Michael Niedermayer <michael@niedermayer.cc> | 2017-03-02 03:02:07 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2017-05-14 12:20:15 +0200 |
| commit | 4071e7eaab8330844bacbb9e807c7bddd896df91 (patch) | |
| tree | 1f7f8ec4d12379811b39c7d0c4a4bc5bb0ccf9a7 | |
| parent | fe4b666707f351daa8b9d164f6828b7a1badaee6 (diff) | |
| download | ffmpeg-4071e7eaab8330844bacbb9e807c7bddd896df91.tar.gz | |
avcodec/mpeg4videodec: Improve the overflow checks in mpeg4_decode_sprite_trajectory()
Also clear the state on errors
Fixes integer overflows in 701/clusterfuzz-testcase-6594719951880192
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit eb41956636fc264fe2077b78ef00591d83bbbace)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/mpeg4videodec.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 7b5a05eda9..8e23578010 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -375,7 +375,7 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g FFABS(s->sprite_offset[1][1]) >= INT_MAX >> shift_c ) { avpriv_request_sample(s->avctx, "Too large sprite shift or offset"); - return AVERROR_PATCHWELCOME; + goto overflow; } for (i = 0; i < 2; i++) { @@ -385,17 +385,23 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g s->sprite_delta[1][i] *= 1 << shift_y; ctx->sprite_shift[i] = 16; - if (llabs(s->sprite_offset[i][0] + s->sprite_delta[i][0] * (int64_t)w) >= INT_MAX || - llabs(s->sprite_offset[i][0] + s->sprite_delta[i][1] * (int64_t)h) >= INT_MAX || - llabs(s->sprite_offset[i][0] + s->sprite_delta[i][0] * (int64_t)w + s->sprite_delta[i][1] * (int64_t)h) >= INT_MAX) { + } + for (i = 0; i < 2; i++) { + if (llabs(s->sprite_offset[0][i] + s->sprite_delta[i][0] * (w+16LL)) >= INT_MAX || + llabs(s->sprite_offset[0][i] + s->sprite_delta[i][1] * (h+16LL)) >= INT_MAX || + llabs(s->sprite_offset[0][i] + s->sprite_delta[i][0] * (w+16LL) + s->sprite_delta[i][1] * (h+16LL)) >= INT_MAX) { avpriv_request_sample(s->avctx, "Overflow on sprite points"); - return AVERROR_PATCHWELCOME; + goto overflow; } } s->real_sprite_warping_points = ctx->num_sprite_warping_points; } return 0; +overflow: + memset(s->sprite_offset, 0, sizeof(s->sprite_offset)); + memset(s->sprite_delta, 0, sizeof(s->sprite_delta)); + return AVERROR_PATCHWELCOME; } static int decode_new_pred(Mpeg4DecContext *ctx, GetBitContext *gb) { |