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 1249948DBA for ; Fri, 26 Apr 2024 23:52:23 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 2825368D385; Sat, 27 Apr 2024 02:52:20 +0300 (EEST) Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [217.70.183.193]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 20FA968CD5C for ; Sat, 27 Apr 2024 02:52:12 +0300 (EEST) Received: by mail.gandi.net (Postfix) with ESMTPSA id 0DBCC240002 for ; Fri, 26 Apr 2024 23:52:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=niedermayer.cc; s=gm1; t=1714175532; 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=0WeOXuYYwuPsVnrFPhZ8CZGNTwRpF/98Bqxkmax47xA=; b=KuXBs5NuHMSzGXlgSKpE0Lt4RWOwdOwRiuCxvsvpaQQ6lnJOlh/3Tla3H5TdPN14vmDpA+ b3ql6lWPMIwap/r2+8u5DLDSVqXeMcZWGNeynSB3uP8zY16c76u9JkU1uS3K2xImD1QSCu Sq6WbnsSUhsbAt3jGHvhXHkTF+rt9x2itLelp8v8V/56SUh51IlaxNDss68mTIs8a0XgZN nxO1GchaRrGNVe/aqyAErXBNUOAqaOGjxrVZcnyunZ4lWkx4mkyOxxYs7auMtIgpvrdGPs ImfSxHbi7aG9tW5EKFYrIrGZ0qEDhVrYUYAuw1acThc+RXmzy60Cq+vYCPCoFw== From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Sat, 27 Apr 2024 01:52:07 +0200 Message-ID: <20240426235211.3718252-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.43.2 MIME-Version: 1.0 X-GND-Sasl: michael@niedermayer.cc Subject: [FFmpeg-devel] [PATCH 1/5] avcodec/pngdec: Check last AVFrame before deref 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: Fixes: NULL pointer dereference Fixes: 68184/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APNG_fuzzer-4926478069334016 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/pngdec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index f7751223b81..b24bfa248dc 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -1218,7 +1218,7 @@ static int decode_fctl_chunk(AVCodecContext *avctx, PNGDecContext *s, return AVERROR_INVALIDDATA; } - if ((sequence_number == 0 || !s->last_picture.f->data[0]) && + if ((sequence_number == 0 || !s->last_picture.f || !s->last_picture.f->data[0]) && dispose_op == APNG_DISPOSE_OP_PREVIOUS) { // No previous frame to revert to for the first frame // Spec says to just treat it as a APNG_DISPOSE_OP_BACKGROUND -- 2.43.2 _______________________________________________ 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".