From 32e971886f52482f76b0f2864183a58f49c158df Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 30 Sep 2023 00:51:29 +0200 Subject: [PATCH] avformat/dxa: Adjust order of operations around block align Fixes: 51896/clusterfuzz-testcase-minimized-ffmpeg_dem_DXA_fuzzer-5730576523198464 Fixes: signed integer overflow: 2147483566 + 82 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 Signed-off-by: Paul B Mahol --- libavformat/dxa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavformat/dxa.c b/libavformat/dxa.c index 58757e8358..813e665a27 100644 --- a/libavformat/dxa.c +++ b/libavformat/dxa.c @@ -123,7 +123,7 @@ static int dxa_read_header(AVFormatContext *s) if(ast->codecpar->block_align) { if (c->bpc > INT_MAX - ast->codecpar->block_align + 1) return AVERROR_INVALIDDATA; - c->bpc = ((c->bpc + ast->codecpar->block_align - 1) / ast->codecpar->block_align) * ast->codecpar->block_align; + c->bpc = ((c->bpc - 1 + ast->codecpar->block_align) / ast->codecpar->block_align) * ast->codecpar->block_align; } c->bytes_left = fsize; c->wavpos = avio_tell(pb);