From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.17.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6FC7F20E3; Thu, 11 Jul 2024 06:00:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.17.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720677651; cv=none; b=FLZU2wSoKW6a+OMN6qEsc16miloDxVtQAv1IxKs528aWx6nSh2Q1bxoR2f3yraBfrSbBSfTDAJtM0WtrLa5Q1ZpQF3qW22gikgXVB5COll4ou+6A5G6I3x4/ib/DvKN098Lcknomr36IftcgLX/d5+YpG33+d4AI3EQnGf+T/NI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720677651; c=relaxed/simple; bh=15yJgavZmfHOIomQLcsyf8HlH0B8GycDnNaojP2vIFw=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=cO1ZbQljcHxnlnZw7alTc2dI6HOHXpPU3UkglMgMatua1hTVqmCh9NYm1m7uwDRn61cuJdEKwQms1jer2ich1iIIPKl4m5s5XdJ5CblDvMEm5YoKHGbypfKYDZCoW7VLmtOspZPqvo7WFZEgrxUhv22EiDWAMP/cBel8bEV/+qY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de; spf=pass smtp.mailfrom=web.de; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b=onZ0lg4L; arc=none smtp.client-ip=212.227.17.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=web.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b="onZ0lg4L" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=web.de; s=s29768273; t=1720677636; x=1721282436; i=markus.elfring@web.de; bh=c5z5eE89ZdgKIAIW2hKoAi6mxSiJBE0HAuchu+r3jpE=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:From:Subject:To: Cc:References:In-Reply-To:Content-Type:Content-Transfer-Encoding: cc:content-transfer-encoding:content-type:date:from:message-id: mime-version:reply-to:subject:to; b=onZ0lg4LU/P7TTOlP2WIBvLsLNPG+qhcOwQWg78btNLs2wt71SxLJSDBEdqjPMWt 6lqzetMVvdlpbBCsyYQmROJNNRkNkekp489199Vh3e7XyI9SoPFqKNfk2t/NGuGp2 DXm8NgI3bQQxvpj9juGLR2RkWHdxhiBFm5ImhnxQ3dtRLJbsoEJPRVuteFPQuEaVF nm8EwvxjGk6LKcIwBxSZ0MOiuewCqIVta5u8pxdyS1Uju1iw5pc39cnm5NyvdbFVh ywDfhXdc6M98noslQEE72n5gaYNR+dOSCkrP5kvOlRsyXqZ2SHc1DcnWsnrg3MmG+ 7D2RI/mW/ItEXe4X2w== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.89.95]) by smtp.web.de (mrweb106 [213.165.67.124]) with ESMTPSA (Nemesis) id 1MxHYA-1sCRu02gwq-00x2l5; Thu, 11 Jul 2024 08:00:36 +0200 Message-ID: Date: Thu, 11 Jul 2024 08:00:15 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Markus Elfring Subject: Re: [fs/bfs 1/2] bfs: fix null-ptr-deref in bfs_move_block To: =?UTF-8?B?0JLQsNGB0LjQu9C40Lkg0JrQvtCy0LDQu9C10LI=?= , linux-fsdevel@vger.kernel.org, lvc-patches@linuxtesting.org, syzbot+d98fd19acd08b36ff422@syzkaller.appspotmail.com Cc: stable@vger.kernel.org, LKML , "Tigran A. Aivazian" , dutyrok@altlinux.org References: <20240710191118.40431-2-kovalev@altlinux.org> <8fd93c4e-3324-49b6-a77c-ea9986bc3033@web.de> Content-Language: en-GB In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:86ZKGI08fjNtBWXHY9MnuWMqn3PBSvK2+nPyLSxvjz7M9h1fSDI lqLtoPG/Hx7oyVpjV20sdIdX+ejpKssu3fPi69yn1P9fW+P5JPlpi4/0vutt+u3s8+95324 NMXBNsXa7we7bDoAjKtOKq4idAobG4YjKjL5Vo1l/+KCd0WXmfhNgZq+DmlM1zKCWgMbq53 stj82fY+93Lgp4jQXEAJA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:POb5WFD1nyk=;cgbCI0MOffS3c4AuoLKqyh9y493 3TX7eB0IgQmMXJdTH3o8PjBXI1Yg0ASIN7LeyoaYXlGtyuG6dLSLoCHzZM19AJCUqUnFKYcbL S5t1AH/+UtyFelSxU+5f3Mo9/xa0gjC2Ms8DUeSizaaQYoJsdzKbZ0q/WZowTZePAMf0yVO0M OPGOYGcup2kDbNfQEZadB6uQGqIb6VjOnDvE9+vcJFocFJHGIzNek28A+wEQ0LSKSkVG6W0F1 EMm9HvGAgPYvpt7Muam67osu9vXMPqF08LNU3xCJSE5Yg327Hw/RZeLRs8rKp5HXbFV48lsof tOsqMsxOchMAtbEuL9J0y8IhgRbugHT/1+h5hSU3kGClaTnJmACw/cOnuG+Mtgd4IwQOwoPAv P7oZJXqOvyr0sbdTeKdoo4byuEg9pt6LfpFauYCYLtZWf79W5MU2JLZdfEOtazeHCFZ88tjLS Jmk7760Wxy2RsKJRHYELcnojIPtTmRFThKtx9QpCQzbU1f536Uy0YscspnaKXC20wm9js9u3+ qUNy1X0rqSRnyTSrLYwidLI9pgV3AnLw2aIjPqIqt45s2HUVoqWuz8na297mlzzrgWW1wSyMO uXNSni+RbRjL6WRpOTqIA58YZXKfN7PsM+4xPsUixSrx2f07BMic4qA2TSjb6N+J3+oqTGdDy k1QKtpVkEZOTP/opnlRk5BbSIcvUp5WU4/Ib4qjIw2zIz6A+OrpDHJCmX1C6idSCSd9HdSGn5 Zy2yeo7w75hNiiYZLAfeGvHL2V/idQ4hx2iicJbqZGHhjqd5nrqibgARnJ64Xvl3ZztTekhkF 5B9IFOLhyNYsvrBYnWLRunBA== > Add a check to ensure that a sb_getblk() call did not return NULL before copying data. How do you think about another refinement for such a change description? Detect a failed sb_getblk() call (before copying data) so that null pointer dereferences should not happen any more. Regards, Markus