From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.ffmpeg.org (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTPS id 74FE248E03 for ; Fri, 15 Aug 2025 21:24:27 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTP id 5FC5668D2CF; Sat, 16 Aug 2025 00:24:22 +0300 (EEST) Received: from 1e8b7847f7d1 (code.ffmpeg.org [188.245.149.3]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTPS id AD0B068CCDF for ; Sat, 16 Aug 2025 00:24:20 +0300 (EEST) MIME-Version: 1.0 From: Marvin Scholz To: ffmpeg-devel@ffmpeg.org Subject: [FFmpeg-devel] =?utf-8?q?=5BPATCH=5D_avformat/mov=3A_Check_that_?= =?utf-8?q?sample=5Fsizes_is_allocated_=28PR_=2320250=29?= 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" Message-Id: <20250815212422.5FC5668D2CF@ffbox0-bg.ffmpeg.org> Date: Sat, 16 Aug 2025 00:24:22 +0300 (EEST) Archived-At: List-Archive: List-Post: PR #20250 opened by Marvin Scholz (ePirat) URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20250 Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20250.patch The previous fix in 0ffe97d9b9e10e88db29d8d910c24ec00ef24edc only checked the count, which is not sufficient. In case there is an invalid (for example truncated) STSZ/STZ2 box, the previously allocated sample_sizes array will be freed. If then another STSZ box is encountered with a non-zero sample_size, the sample_count will be written without a new sample_sizes array being allocated. Fixes: NULL pointer dereference Fixes: 437528618/clusterfuzz-testcase-minimized-ffmpeg_dem_MOV_fuzzer-6537287645331456 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg >From 3ebb021ebd9703eaa6d1106eaebc2e358dcb3e32 Mon Sep 17 00:00:00 2001 From: Marvin Scholz Date: Fri, 15 Aug 2025 23:05:53 +0200 Subject: [PATCH] avformat/mov: Check that sample_sizes is allocated The previous fix in 0ffe97d9b9e10e88db29d8d910c24ec00ef24edc only checked the count, which is not sufficient. In case there is an invalid (for example truncated) STSZ/STZ2 box, the previously allocated sample_sizes array will be freed. If then another STSZ box is encountered with a non-zero sample_size, the sample_count will be written without a new sample_sizes array being allocated. Fixes: NULL pointer dereference Fixes: 437528618/clusterfuzz-testcase-minimized-ffmpeg_dem_MOV_fuzzer-6537287645331456 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg --- libavformat/mov.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavformat/mov.c b/libavformat/mov.c index 86037c6712..d6fcb0c5dc 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -10472,7 +10472,7 @@ static int mov_parse_heif_items(AVFormatContext *s) st->codecpar->height = item->height; err = sanity_checks(s, sc, item->item_id); - if (err || !sc->sample_count) + if (err || !sc->sample_sizes) return AVERROR_INVALIDDATA; sc->sample_sizes[0] = item->extent_length; -- 2.49.1 _______________________________________________ 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".