From f2abd36b3863188894fd21964c662b6c17268bfb Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 5 Jun 2018 13:19:35 +0200 Subject: [PATCH] avcodec/shorten: Fix multiple integer overflows Fixes: signed integer overflow: 3 * 1006632960 cannot be represented in type 'int' Fixes: 8278/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SHORTEN_fuzzer-5692857166856192 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/shorten.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/shorten.c b/libavcodec/shorten.c index 0bd3e1e5f7..18a12d0b97 100644 --- a/libavcodec/shorten.c +++ b/libavcodec/shorten.c @@ -389,7 +389,7 @@ static int decode_subframe_lpc(ShortenContext *s, int command, int channel, for (i = 0; i < s->blocksize; i++) { sum = init_sum; for (j = 0; j < pred_order; j++) - sum += coeffs[j] * s->decoded[channel][i - j - 1]; + sum += coeffs[j] * (unsigned)s->decoded[channel][i - j - 1]; s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> qshift); } @@ -700,7 +700,7 @@ static int shorten_decode_frame(AVCodecContext *avctx, void *data, /* update means with info from the current block */ if (s->nmean > 0) { - int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2; + int64_t sum = (s->version < 2) ? 0 : s->blocksize / 2; for (i = 0; i < s->blocksize; i++) sum += s->decoded[channel][i];