From 1eb8cbd09c5f22d7ba9e0d443712a6ab80648637 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 26 Mar 2024 03:14:08 +0100 Subject: [PATCH] avcodec/wavarc: avoid signed integer overflow in AC code Fixes: 62285/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVARC_fuzzer-659847401740697 Fixes: signed integer overflow: 65312 * 34078 cannot be represented in type 'int' Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/wavarc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavcodec/wavarc.c b/libavcodec/wavarc.c index 99cbaf0109..aa1af6330b 100644 --- a/libavcodec/wavarc.c +++ b/libavcodec/wavarc.c @@ -414,7 +414,7 @@ static int ac_init(AVCodecContext *avctx, static uint16_t ac_get_prob(WavArcContext *s) { - return ((s->freq_range - 1) + (s->ac_value - s->ac_low) * s->freq_range) / + return ((s->freq_range - 1) + (s->ac_value - s->ac_low) * (unsigned)s->freq_range) / ((s->ac_high - s->ac_low) + 1U); } @@ -439,8 +439,8 @@ static int ac_normalize(AVCodecContext *avctx, WavArcContext *s, GetBitContext * goto fail; range = (s->ac_high - s->ac_low) + 1; - s->ac_high = (range * s->range_high) / s->freq_range + s->ac_low - 1; - s->ac_low += (range * s->range_low) / s->freq_range; + s->ac_high = (range * (unsigned)s->range_high) / s->freq_range + s->ac_low - 1; + s->ac_low += (range * (unsigned)s->range_low) / s->freq_range; if (s->ac_high < s->ac_low) goto fail;