From 68cc1744db828e929b74f96478c18f1d226510be Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 5 Oct 2023 00:19:53 +0200 Subject: [PATCH] avcodec/evc_parse: Check tid The check is based on not infinite looping. It is likely a more strict check can be done Fixes: Infinite loop Fixes: 62473/clusterfuzz-testcase-minimized-ffmpeg_BSF_EVC_FRAME_MERGE_fuzzer-5719883750703104 Fixes: 62765/clusterfuzz-testcase-minimized-ffmpeg_dem_EVC_fuzzer-6448531252314112 Fixes: 63378/clusterfuzz-testcase-minimized-ffmpeg_dem_MPEGPS_fuzzer-6504993844494336 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Reviewed-by: "Dawid Kozinski/Multimedia (PLT) /SRPOL/Staff Engineer/Samsung Electronics" Signed-off-by: Michael Niedermayer --- libavcodec/evc_parse.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c index 255706ce61..43b8dabf8b 100644 --- a/libavcodec/evc_parse.c +++ b/libavcodec/evc_parse.c @@ -174,6 +174,9 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh, } else { int SubGopLength = 1 << sps->log2_sub_gop_length; + if (tid > (SubGopLength > 1 ? 1 + av_log2(SubGopLength - 1) : 0)) + return AVERROR_INVALIDDATA; + if (tid == 0) { poc->PicOrderCntVal = poc->prevPicOrderCntVal + SubGopLength; poc->DocOffset = 0;