From 2cebde69e031b638f3439dfce4c729424aa294ca Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 1 Jul 2020 21:27:23 +0200 Subject: [PATCH] avcodec/dstdec: Replace AC overread check by sample rate check Real files do skip coding 0 bits at the end, thus this kind of check does not work reliable. Fixes: Ticket 8770 Fixes: dst-256fs44-6ch-refdstencoder.dff The samplerate is specified in ISO/IEC 14496-3:2005(E) as one of 3 fixed values, this also can be used to limit the duration and avoid the timeout This reverts commit f6df99dba1ae64b05d08fba8160d13eb9795042f. (cherry picked from commit 1679f23beb3cfc3639352b3cbe7c08c00189c6b0) Signed-off-by: Michael Niedermayer --- libavcodec/dstdec.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/libavcodec/dstdec.c b/libavcodec/dstdec.c index a38360fb95..ebba6cc2c9 100644 --- a/libavcodec/dstdec.c +++ b/libavcodec/dstdec.c @@ -85,6 +85,12 @@ static av_cold int decode_init(AVCodecContext *avctx) return AVERROR_PATCHWELCOME; } + // the sample rate is only allowed to be 64,128,256 * 44100 by ISO/IEC 14496-3:2005(E) + // We are a bit more tolerant here, but this check is needed to bound the size and duration + if (avctx->sample_rate > 512 * 44100) + return AVERROR_INVALIDDATA; + + if (DST_SAMPLES_PER_FRAME(avctx->sample_rate) & 7) { return AVERROR_PATCHWELCOME; }