From patchwork Mon May 10 10:20:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 433066 Delivered-To: patch@linaro.org Received: by 2002:a02:c901:0:0:0:0:0 with SMTP id t1csp2710291jao; Mon, 10 May 2021 03:40:55 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxss0kFxvmT91fz7HwRJbSIfRSZfYGhLlrbax04sVs7xGhXzyIWxdw3XFl+MTmGGp7AWZNs X-Received: by 2002:a05:6402:1c07:: with SMTP id ck7mr28841813edb.149.1620643255755; Mon, 10 May 2021 03:40:55 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1620643255; cv=none; d=google.com; s=arc-20160816; b=DfyTEeDWbXmqKPevzXbhYUCMd++YRnMfr5oI9PFmUS453JPn+10HDNyMoR+8IBdcpy F+HZ7UjtmYjVRbw7iGYJCin3ViEm+waahlQx51V6gdU5BKBksUtfZj1QhfMJy8TqIHkU ltGtzUk/3U597619PjPeoTo+fzwCgfPSj4ZhecJDdBswlbd4HAfT4gcduVyYuc1a3k32 4dYRVILr3Mtw83FXic13zldGYZhqGGEApf3fg5Ufob8ShMPlovEKwRSscWgP+W0nggbL I6cKtCM9vgqAu4WJ3dmDTVM8a1VodgsC2FqBW1Iz0yz0N8eAxSfh77/lJpoxXI6XlzFA Hr7Q== 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=eE5s2A5XjhtrWZlR8UM4mhv6ZlkWgo2CrCZnGqZn6dFMTfP7Eh/CLMDwRNiuLeY/Bk O5Znwz5QBeysEbY3xVfuoMSZFs9ejJxYUCEVT6HeCVUjQFkotiBxArSh3h4YhmDK64lG oQFLU3bmyTT1QGDO4+W0gMaA+sTzclwoL42zhSS8OCHW+zON+kUz2Ho+jSjFv9Eiz+iI heWEnpb4bvl+7ie79Ed+I7EhIRNO6vpPeUHCH4DnZdVK59f1J3OkT/8pr3Lhs53EWQMv a6WHTYN5w5tBf+jWnikjCwnKWceLjnhmWoz5SuPyQbI0VO8VkaotVq2fhJEXzW/wyNuE ZPfw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=cONWBwIp; 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 t19si13813436edw.191.2021.05.10.03.40.55; Mon, 10 May 2021 03:40:55 -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=cONWBwIp; 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 S232006AbhEJKlv (ORCPT + 12 others); Mon, 10 May 2021 06:41:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:48608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232064AbhEJKh6 (ORCPT ); Mon, 10 May 2021 06:37:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7214D61944; Mon, 10 May 2021 10:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620642594; bh=6aDdcVRD5XDeRzPu5cDpy+CeTozswdh322xviITHbFE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cONWBwIpngOjyZ3aml8NRQsaFpKqlIKpApeWZmM7777pdO4O2oAc4cMGuyquS4b9G 54KIgTtFL/jj8uN0ERYyqIohbNsVQxRfPsvsYIEOPo0j0CVJV+/QZLQ5vbm6rFCxto kUrZVNZgUjzYIl1HgS5UYoylDdXcTCw0HNqby8CY= 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 5.4 157/184] security: commoncap: fix -Wstringop-overread warning Date: Mon, 10 May 2021 12:20:51 +0200 Message-Id: <20210510101955.260466315@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510101950.200777181@linuxfoundation.org> References: <20210510101950.200777181@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;