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| author | Michael Niedermayer <michael@niedermayer.cc> | 2019-12-07 20:38:13 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2020-01-11 23:31:18 +0100 |
| commit | c0bd5fa43d193aa389bea7c5176b2fe23f6eeddd (patch) | |
| tree | a86cae2bbeb1fa3c0afb9a6f4df90a5012d945b6 | |
| parent | fea90e9438b0eaf529b756585b78c579051f1b38 (diff) | |
avcodec/g729postfilter: Optimize out overflowing multiplication from apply_tilt_comp()
Fixes: signed integer overflow: -1114392282 * 2 cannot be represented in type 'int'
Fixes: 19236/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G729_fuzzer-5741678938030080
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/g729postfilter.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/libavcodec/g729postfilter.c b/libavcodec/g729postfilter.c index fc9a8d54cc..ab668594d2 100644 --- a/libavcodec/g729postfilter.c +++ b/libavcodec/g729postfilter.c @@ -486,14 +486,14 @@ static int16_t apply_tilt_comp(int16_t* out, int16_t* res_pst, int refl_coeff, if (refl_coeff > 0) { gt = (refl_coeff * G729_TILT_FACTOR_PLUS + 0x4000) >> 15; - fact = 0x4000; // 0.5 in (0.15) - sh_fact = 15; + fact = 0x2000; // 0.5 in (0.15) + sh_fact = 14; } else { gt = (refl_coeff * G729_TILT_FACTOR_MINUS + 0x4000) >> 15; - fact = 0x800; // 0.5 in (3.12) - sh_fact = 12; + fact = 0x400; // 0.5 in (3.12) + sh_fact = 11; } - ga = (fact << 15) / av_clip_int16(32768 - FFABS(gt)); + ga = (fact << 16) / av_clip_int16(32768 - FFABS(gt)); gt >>= 1; /* Apply tilt compensation filter to signal. */ @@ -503,12 +503,12 @@ static int16_t apply_tilt_comp(int16_t* out, int16_t* res_pst, int refl_coeff, tmp2 = (gt * res_pst[i-1]) * 2 + 0x4000; tmp2 = res_pst[i] + (tmp2 >> 15); - tmp2 = (tmp2 * ga * 2 + fact) >> sh_fact; + tmp2 = (tmp2 * ga + fact) >> sh_fact; out[i] = tmp2; } tmp2 = (gt * ht_prev_data) * 2 + 0x4000; tmp2 = res_pst[0] + (tmp2 >> 15); - tmp2 = (tmp2 * ga * 2 + fact) >> sh_fact; + tmp2 = (tmp2 * ga + fact) >> sh_fact; out[0] = tmp2; return tmp; |