From 067485b673f6ac4b1207d6fc975d1fd968edc68e Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 19 Feb 2017 20:32:48 +0100 Subject: [PATCH] avcodec/eac3dec: Fix runtime error: left shift of negative value Fixes: 610/clusterfuzz-testcase-4831030085156864 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/eac3dec.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavcodec/eac3dec.c b/libavcodec/eac3dec.c index 83a54bcfab..be2350237e 100644 --- a/libavcodec/eac3dec.c +++ b/libavcodec/eac3dec.c @@ -252,7 +252,7 @@ static void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch) /* Vector Quantization */ int v = get_bits(gbc, bits); for (blk = 0; blk < 6; blk++) { - s->pre_mantissa[ch][bin][blk] = ff_eac3_mantissa_vq[hebap][v][blk] << 8; + s->pre_mantissa[ch][bin][blk] = ff_eac3_mantissa_vq[hebap][v][blk] * (1 << 8); } } else { /* Gain Adaptive Quantization */ @@ -271,12 +271,12 @@ static void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch) int b; int mbits = bits - (2 - log_gain); mant = get_sbits(gbc, mbits); - mant <<= (23 - (mbits - 1)); + mant = ((unsigned)mant) << (23 - (mbits - 1)); /* remap mantissa value to correct for asymmetric quantization */ if (mant >= 0) b = 1 << (23 - log_gain); else - b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] << 8; + b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] * (1 << 8); mant += ((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (int64_t)mant) >> 15) + b; } else { /* small mantissa, no GAQ, or Gk=1 */