From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 368B44BBE4 for ; Mon, 15 Jul 2024 14:48:36 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 6C19F68D941; Mon, 15 Jul 2024 17:48:34 +0300 (EEST) Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [217.70.183.199]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 6383568D8C2 for ; Mon, 15 Jul 2024 17:48:27 +0300 (EEST) Received: by mail.gandi.net (Postfix) with ESMTPSA id 881A1FF807 for ; Mon, 15 Jul 2024 14:48:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=niedermayer.cc; s=gm1; t=1721054906; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=FOg13n+9xm10wUb6G258GeRVpy3DfA/280mAuQvrrDQ=; b=P/IMGtJAGY4cSIVzLiW9wCyRrfmqy76ST3OUuEjTM/kDAjdn9S5OyWwHVNDXNpCQXfl+Fb iNFjclKzdZmdalm0h3QKtEcEgxDXWrQssxFXj+z48iVo96mJ+ZnjC07xAmES2+fSHVUMJg YtpFD7FqUV4eBkg0uxY6CZ+w4OHz38P7auAdzeIDEudMqy7HUuaOYmSEUa+DKyKXRwkgYq ebK7CRq+q6/Yz/JuNrodL1eI0s3Jb6K8rW2auE74hWW+jT1ctvbnjFj3G4ROO7Ieu72/99 eSVWEQwF19cBT1XufkPwwWVe50tp+yuCUIWBWgLFoQHsZc05OODKXDWPuY28nA== From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Mon, 15 Jul 2024 16:48:25 +0200 Message-ID: <20240715144825.3652038-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 X-GND-Sasl: michael@niedermayer.cc Subject: [FFmpeg-devel] [PATCH v2] avcodec/hevc/hevcdec: Do not allow slices to depend on failed slices X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: An alternative would be to leave the context unchanged on failure of hls_slice_header() Fixes: out of array access Fixes: NULL pointer dereference Fixes: 69584/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-5931086299856896 Fixes: 69724/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-5104066422702080 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/hevc/hevcdec.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/libavcodec/hevc/hevcdec.c b/libavcodec/hevc/hevcdec.c index 0e4b26dad3b..80d59ab1916 100644 --- a/libavcodec/hevc/hevcdec.c +++ b/libavcodec/hevc/hevcdec.c @@ -621,6 +621,10 @@ static int hls_slice_header(SliceHeader *sh, const HEVCContext *s, GetBitContext if (pps->dependent_slice_segments_enabled_flag) sh->dependent_slice_segment_flag = get_bits1(gb); + if (sh->dependent_slice_segment_flag && !s->slice_initialized) { + av_log(s->avctx, AV_LOG_ERROR, "dependent slice failed\n"); + return AVERROR_INVALIDDATA; + } slice_address_length = av_ceil_log2(sps->ctb_width * sps->ctb_height); @@ -893,9 +897,6 @@ static int hls_slice_header(SliceHeader *sh, const HEVCContext *s, GetBitContext } else { sh->slice_loop_filter_across_slices_enabled_flag = pps->seq_loop_filter_across_slices_enabled_flag; } - } else if (!s->slice_initialized) { - av_log(s->avctx, AV_LOG_ERROR, "Independent slice segment missing.\n"); - return AVERROR_INVALIDDATA; } sh->num_entry_point_offsets = 0; @@ -3155,8 +3156,11 @@ static int decode_slice(HEVCContext *s, const H2645NAL *nal, GetBitContext *gb) int ret; ret = hls_slice_header(&s->sh, s, gb); - if (ret < 0) + if (ret < 0) { + //The code is not capable to rewind from an error, the state now is inconsistant so we cannot use it on depandant slices + s->slice_initialized = 0; return ret; + } if ((s->avctx->skip_frame >= AVDISCARD_BIDIR && s->sh.slice_type == HEVC_SLICE_B) || (s->avctx->skip_frame >= AVDISCARD_NONINTRA && s->sh.slice_type != HEVC_SLICE_I) || -- 2.45.2 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".