diff options
author | Michael Niedermayer <michael@niedermayer.cc> | 2018-09-15 01:20:38 +0300 |
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committer | Michael Niedermayer <michael@niedermayer.cc> | 2018-10-03 13:32:56 +0300 |
commit | 49023147c7fcb8319830be698b280e65e82ddf22 (patch) | |
tree | df54174d84cfa8d97f43453f8b0fbfa627066e94 /libavcodec/mpeg4videodec.c | |
parent | 79c018351e6e0a3e3f58b4b7831a6642c3a4f42c (diff) |
avcodec/mpeg4videodec: Fix undefined shift in get_amv()
Fixes: runtime error: shift exponent -1 is negative
Fixes: 9938/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG4_fuzzer-5653783529914368
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 c88afa44c4823aba7b6f4a1b01fd6a4169643c57)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Diffstat (limited to 'libavcodec/mpeg4videodec.c')
-rw-r--r-- | libavcodec/mpeg4videodec.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 23dde9ee85..936406d2d1 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -537,7 +537,7 @@ static inline int get_amv(Mpeg4DecContext *ctx, int n) len >>= s->quarter_sample; if (s->real_sprite_warping_points == 1) { - if (ctx->divx_version == 500 && ctx->divx_build == 413) + if (ctx->divx_version == 500 && ctx->divx_build == 413 && a >= s->quarter_sample) sum = s->sprite_offset[0][n] / (1 << (a - s->quarter_sample)); else sum = RSHIFT(s->sprite_offset[0][n] * (1 << s->quarter_sample), a); |