From f51e4d026cc762ff2d47d6107658dbff42ba5ea8 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 20 Aug 2019 16:52:07 +0200 Subject: [PATCH] avcodec/alsdec: Limit maximum channels to 512 There seems to be no limit in the specification and upto 64k could be stored 512 is choosen as limit as thats the maximum in a conformance sample An alternative to this patch would be a max_channels variable Fixes: OOM Fixes: 16200/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5764788793114624 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Suggested-by: Thilo Borgmann Reviewed-by: Thilo Borgmann Signed-off-by: Michael Niedermayer --- libavcodec/alsdec.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c index 26c496c769..1fdd0cb0fe 100644 --- a/libavcodec/alsdec.c +++ b/libavcodec/alsdec.c @@ -348,6 +348,11 @@ static av_cold int read_specific_config(ALSDecContext *ctx) if (als_id != MKBETAG('A','L','S','\0')) return AVERROR_INVALIDDATA; + if (avctx->channels > FF_SANE_NB_CHANNELS) { + avpriv_request_sample(avctx, "Huge number of channels\n"); + return AVERROR_PATCHWELCOME; + } + ctx->cur_frame_length = sconf->frame_length; // read channel config