From 6580a7b2b27973947118482235a2eb1214d968a2 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 7 Sep 2023 02:13:13 +0200 Subject: [PATCH] avcodec/celp_math: avoid overflow in shift by making gain unsigned we have 1 bit more available alternatively we can clip twice as in the g729 reference Fixes: left shift of 23404 by 17 places cannot be represented in type 'int' Fixes: 61728/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ACELP_KELVIN_fuzzer-6280412547383296 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/celp_math.h | 2 +- libavcodec/g729postfilter.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/libavcodec/celp_math.h b/libavcodec/celp_math.h index 18888a425d..99a0470719 100644 --- a/libavcodec/celp_math.h +++ b/libavcodec/celp_math.h @@ -78,7 +78,7 @@ int64_t ff_dot_product(const int16_t *a, const int16_t *b, int length); * * @return value << offset, if offset>=0; value >> -offset - otherwise */ -static inline int bidir_sal(int value, int offset) +static inline unsigned bidir_sal(unsigned value, int offset) { if(offset < 0) return value >> -offset; else return value << offset; diff --git a/libavcodec/g729postfilter.c b/libavcodec/g729postfilter.c index 26e937f0ba..382db92432 100644 --- a/libavcodec/g729postfilter.c +++ b/libavcodec/g729postfilter.c @@ -581,7 +581,7 @@ void ff_g729_postfilter(AudioDSPContext *adsp, int16_t* ht_prev_data, int* voici int16_t ff_g729_adaptive_gain_control(int gain_before, int gain_after, int16_t *speech, int subframe_size, int16_t gain_prev) { - int gain; // (3.12) + unsigned gain; // (3.12) int n; int exp_before, exp_after; @@ -603,7 +603,7 @@ int16_t ff_g729_adaptive_gain_control(int gain_before, int gain_after, int16_t * gain = ((gain_before - gain_after) << 14) / gain_after + 0x4000; gain = bidir_sal(gain, exp_after - exp_before); } - gain = av_clip_int16(gain); + gain = FFMIN(gain, 32767); gain = (gain * G729_AGC_FAC1 + 0x4000) >> 15; // gain * (1-0.9875) } else gain = 0;