From c897a9285846b6a072b9650976afd4f091b7a71f Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 5 Nov 2017 21:20:05 +0100 Subject: [PATCH] avcodec/snowdec: Fix integer overflow in header parsing Fixes: 3984/clusterfuzz-testcase-minimized-5265759929368576 Fixes: runtime error: signed integer overflow: -1085585801 + -1094995529 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/snowdec.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c index 13668c2105..727e908fb5 100644 --- a/libavcodec/snowdec.c +++ b/libavcodec/snowdec.c @@ -374,7 +374,7 @@ static int decode_header(SnowContext *s){ } } - s->spatial_decomposition_type+= get_symbol(&s->c, s->header_state, 1); + s->spatial_decomposition_type+= (unsigned)get_symbol(&s->c, s->header_state, 1); if(s->spatial_decomposition_type > 1U){ av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_type %d not supported\n", s->spatial_decomposition_type); return AVERROR_INVALIDDATA; @@ -390,10 +390,10 @@ static int decode_header(SnowContext *s){ } - s->qlog += get_symbol(&s->c, s->header_state, 1); - s->mv_scale += get_symbol(&s->c, s->header_state, 1); - s->qbias += get_symbol(&s->c, s->header_state, 1); - s->block_max_depth+= get_symbol(&s->c, s->header_state, 1); + s->qlog += (unsigned)get_symbol(&s->c, s->header_state, 1); + s->mv_scale += (unsigned)get_symbol(&s->c, s->header_state, 1); + s->qbias += (unsigned)get_symbol(&s->c, s->header_state, 1); + s->block_max_depth+= (unsigned)get_symbol(&s->c, s->header_state, 1); if(s->block_max_depth > 1 || s->block_max_depth < 0 || s->mv_scale > 256U){ av_log(s->avctx, AV_LOG_ERROR, "block_max_depth= %d is too large\n", s->block_max_depth); s->block_max_depth= 0;