From patchwork Mon May 10 10:21:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 433090 Delivered-To: patch@linaro.org Received: by 2002:a02:c901:0:0:0:0:0 with SMTP id t1csp2756529jao; Mon, 10 May 2021 04:43:36 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzHSCiBRWN+gaf5za7iroZTDJIyNo17zlaB1A8hnyNrgR+G0YOIMOyG6bUTsufmCTspkPDc X-Received: by 2002:a17:906:3c4e:: with SMTP id i14mr24945444ejg.245.1620646915157; Mon, 10 May 2021 04:41:55 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1620646915; cv=none; d=google.com; s=arc-20160816; b=aVosQa9nk82AEEr31ldkV6A9HXlSLDm5Swd7R7zkIzB7r/hKqrp36Naq+EIIZmThq+ h9HEGr206hUfxLBMJoPayvkDG7iRScJrNfHTWeGnqLGHzQ42xAxKGUuLh60x40sBhZTS 9NxjmhuSp5wpjm9tP7oa2faI0raQ7sN/H2VdrduLpwb1JZ/1tNpDRl2AFxLKLOy6tfSj gcI4bYEZOPmvsYFk78echFEddWQHMr8kqV4i4oJMv4oh2Rb8UvUEXy+BGnKaxNbb2EIJ WILEU6oQ97pzTLkr1ELc4bonoE0cAI4pGcgbj5AtpKgfxc6mGF4co2pI9djciMOeWwlf FeMA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=DXlnq0aWud/fnMo/2wTp+6EzVkLdA2p0NG5ewyC66vo=; b=WjMBdUCu5i0cb4mT1ul0BRHdLS4kt51XpKkOST7LgxTYJYZGniQJY3ThxCITn047IO mYcyoe/W3JMUYhuvcYVSI8fYEwfQLFTA9p8yF/h/dvoPGh5gHiNhYe6FW7U9OORHD5nj 4lT7dab1jW7rv/DMIVcbOlKhMDKcRQl/Rg1/G4pq/QeFejSWKk50EIXwoY2Svpg3QGVs tPxCyk9Wxy21ZRikMIUZRscd/oh41HfG7p0HQXgspzjw+DD7URTGNTq+EDalDK2K3+pw TtAJO7LAY4Kj7H37dnHPAivkN1ulp3ROYDvy6aSxGvaYAJOJB9R0gtMTHTWuEtevu46r lNDA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=wpXnFVee; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id r17si13500365edw.273.2021.05.10.04.41.54; Mon, 10 May 2021 04:41:55 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=wpXnFVee; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234588AbhEJLNB (ORCPT + 12 others); Mon, 10 May 2021 07:13:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:44332 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235854AbhEJLGW (ORCPT ); Mon, 10 May 2021 07:06:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A930D60FE3; Mon, 10 May 2021 10:56:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620644199; bh=6aDdcVRD5XDeRzPu5cDpy+CeTozswdh322xviITHbFE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wpXnFVeeKCC2tns4e0LHH3pFZegfLWpAJQoXjMv6MsqzyKSuCqotc7nkOGXIzEikz SvUI0OGsVftVKxmy7DtIeut0iTDIvFlJ+qtmMTqiIK3WUEBIk3FcZpI94zPOdhx+4w 6QB/7luv9Z7olwx7e5aTr16rHvH5kHH3gR2Y2EEU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Christian Brauner , James Morris , Andrey Zhizhikin Subject: [PATCH 5.11 293/342] security: commoncap: fix -Wstringop-overread warning Date: Mon, 10 May 2021 12:21:23 +0200 Message-Id: <20210510102019.796657790@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102010.096403571@linuxfoundation.org> References: <20210510102010.096403571@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnd Bergmann commit 82e5d8cc768b0c7b03c551a9ab1f8f3f68d5f83f upstream. gcc-11 introdces a harmless warning for cap_inode_getsecurity: security/commoncap.c: In function ‘cap_inode_getsecurity’: security/commoncap.c:440:33: error: ‘memcpy’ reading 16 bytes from a region of size 0 [-Werror=stringop-overread] 440 | memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The problem here is that tmpbuf is initialized to NULL, so gcc assumes it is not accessible unless it gets set by vfs_getxattr_alloc(). This is a legitimate warning as far as I can tell, but the code is correct since it correctly handles the error when that function fails. Add a separate NULL check to tell gcc about it as well. Signed-off-by: Arnd Bergmann Acked-by: Christian Brauner Signed-off-by: James Morris Cc: Andrey Zhizhikin Signed-off-by: Greg Kroah-Hartman --- security/commoncap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/security/commoncap.c +++ b/security/commoncap.c @@ -391,7 +391,7 @@ int cap_inode_getsecurity(struct inode * &tmpbuf, size, GFP_NOFS); dput(dentry); - if (ret < 0) + if (ret < 0 || !tmpbuf) return ret; fs_ns = inode->i_sb->s_user_ns;