From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgau1.qq.com (smtpbgau1.qq.com [54.206.16.166]) (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 101243BB674 for ; Thu, 27 Aug 2026 08:05:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.206.16.166 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787817959; cv=none; b=BHRS/935QkTnhAF3DF+71g1WFiPscXd7mZjt4srxhHcVipq4ScPoe90i76c4d3t1FiRK4YkFp6mZlk3/lXWm89BiVk8m5PHLEs+kdnzG7Y/HpLCt+D2+qFqr2O4OYc2gWAvMJHjmz1OOOyYGu0f7yfSECG2uhPZCzwdxPkiWcOI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787817959; c=relaxed/simple; bh=9CVWleTaSrdVhxxRUhw4ZUJyn3Jg9XY0R1skItqGr00=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=LfCjWrzqlC2LardlSwNt2cRKcLWkmeTpuHZS5ArfhoQGCxh+j4xpQHtGTOMevpaa5YJP7xodnANC/J8/SBcAGbWhx0LeUZkCSg3vK+fq/Fd2KXHRqqgo0pTVif0JL1hymoatVy2hNHj643MNosBaJ6mLEMFEaKUuKjZ33NXC7fc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com; spf=pass smtp.mailfrom=uniontech.com; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b=n+NVd3oQ; arc=none smtp.client-ip=54.206.16.166 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=uniontech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b="n+NVd3oQ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1787817928; bh=QoH1s/dQqMRnerLRulBMAWipEN11a7O5ilwtRmrJkUc=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=n+NVd3oQvZOwC8G3DpOMhkkwycbp4CFzffgq/6jMZjZXvo5C1xGurOMe3IlbLBmPP yG3Ds1ou4UaxCnD4fMIXDjTBc35qXt9PWEYw7cIJ0Q7s+XYZn0zn6a2x7p6fxcnscI FAhDmwXBkmqAJ6dRmoHWG84F1nO7xOJVhELU3amw= X-QQ-mid: zesmtpgz5t1787817922te8c9b670 X-QQ-Originating-IP: mOk7kULihjnbT2BpzspnOIplwfDxYHLmryj7MxW7dqU= Received: from uniontech.com ( [113.57.152.160]) by bizesmtp.qq.com (ESMTP) with id ; Thu, 27 Aug 2026 16:05:20 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 1 X-BIZMAIL-ID: 11851014657286288873 From: Yichong Chen To: dhowells@redhat.com Cc: netfs@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cachefiles: fix out-of-bounds read in coherency trace Date: Thu, 27 Aug 2026 16:05:20 +0800 Message-Id: <20260827080520.2410207-1-chenyichong@uniontech.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <1924988.1787815878@warthog.procyon.org.uk> References: <1924988.1787815878@warthog.procyon.org.uk> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: zesmtpgz:uniontech.com:qybglogicsvrgz:qybglogicsvrgz3a-0 X-QQ-XMAILINFO: METBPFwEUDZ+UD7wuFRW848CLi3z1KE5VwH+3z1cLr+sdd1MLKsmeRSf jsg7pG+94fGF0g9KuWADsaUfsYAwlja77dtBP9wjKvSlPu+VP0G/7gstdZr+tE8okNsGvDt 7ghUpKFoZj1aXCCkJGlGPOnjxkoSskIabr2shJh5v3d9tszLP84RIQj9M+FC82Vsn7rujoG PbdR3eSYM7puZr+TU9dV0TYQI2yAB3puFfWJcvqZ1bLNPg4180o/AeCMxYBpW/WjUSotZMT 3ux6ISTlP66lKlWcGdUxcIx2LTqR3YjSVYElNgO90Gf2sNue2zZRwZoq44Z3uEuHIW8L1aN e9N9aXSzdPJO1Tc+vR+CTzIsAfPgSry2c64vqRdE9FuUQCTQNZ9gmjsOfvMz2kjfOhjMdW9 W/P29whPCUWonxfnOw8iEvV4nFOMZKFIJ+2720LKLTeNBe9bxBHk0/24tJ5PEUd5GdhJDSd j3iBc3o98WMD6aL5z1Gl7+5usM+0E1vB4bIOiYsRIqqrqYn+Ru0kEk1xJQNM9bzZLFWZkq+ MZRN/4Pf0xNhQ2aHD+TeVl5O7H6KwB5Cp/LDSwaNqMbGmsJaBPTnSoiK5M28j7C9gbsRV2f TCMV/5wgllUvXMse0PnsGbRTSKtVIgW3zYunHLp3bLORPICh3+KPmXM1Krk+kst3C+Y0E2G ZIphXnTrQYj2QDwz+5IgDMgMWlzCuSTxbvBy5iVNh3s+DfCZln9tM+tZX78Akzo4yTvymxU OpV04LxNeJQHvzI9u4XXQf/itGeTCsKVYDw9fiCIy0A5hWzrLnMP5tEUBi0g+MQ8vcaIuDN BSGtpbyETxxFnPa5SeHYElxsL/uqoGHbGNP8W3+Wlcc60ITJCTVAmuuW+SioWl1YiF0UJ7k w8TBtjrqZK8mNTvNCTO7njYY9rmhKmyH4lEqv1WiQgEvUnc9BZ1OB7/GKgjB3yXdNoHovTi xu5ZNWeDaEw0ESMSwVmJPj5lQvWMjhaWpjyzzaVaJVsoT7U1zrCDQFSeb5dTXzoX2e1cJSD NCvLCtIg+jqLNMi8rI6gFch0amW/j1Pu8v0bFsuXqTTXBSw7BktnDy1/4kswtp1KWVoUYJp aKrs2qrcrom X-QQ-XMRINFO: MSVp+SPm3vtSI1QTLgDHQqIV1w2oNKDqfg== X-QQ-RECHKSPAM: 0 On Thu, Aug 27, 2026 at 08:31:18AM +0100, David Howells wrote: > Thanks, but I have a patch for this. See patch 9 here: > > https://lore.kernel.org/linux-fsdevel/20260825132045.1000787-1-dhowells@redhat.com/ > > I don't want to call memcpy() like this just for the purposes of a tracepoint > that is almost certainly not actually be active. > > You're also moving buf->content into a variable rather than using it directly > - is there a reason for that? Thanks for pointing me to your patch. The local content variable was intended to avoid reading fields from the xattr buffer on the getxattr failure path, where the buffer contents may not be valid. Your patch already handles the short auxiliary data case by making room for the traced bytes and pre-clearing them, so please ignore my patch. I'll drop it on my side. Thanks, Yichong