From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41E54C433DB for ; Mon, 8 Feb 2021 18:08:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EBF8764E37 for ; Mon, 8 Feb 2021 18:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235296AbhBHSHg (ORCPT ); Mon, 8 Feb 2021 13:07:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:46604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235239AbhBHSDk (ORCPT ); Mon, 8 Feb 2021 13:03:40 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1A53064EE8; Mon, 8 Feb 2021 17:59:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612807192; bh=egN8kW5Z55ckGja4eJwQaEtGjHmBhaSTC0Nr0vjE+as=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S5ING7HJa4ZByhVgPsa0RMYaZqke4AtSq+9gKMQvXeg0TRARY9vc4SixZxoIa3004 CUAj3cT2kdbZjZkufKW1HIc8Fc3QKEZ8CimL8xZQLadiXMclHyl62Mx2prKybK8rq3 4tIFp0PTcDDMxF0NQYcRSvBVz53vELHweYOacAAcYYFLhRqBa+vUe64SIz0XZTgGfZ biq2Joth9efQGCAY3RZs7XuedtZbRWDzJqLKGYeJGZgHM6VK0/9VwfKbGFbEIfGw0M 5lLJkOS99ysSMePCi7D5yNOJFjkefNRpiW+EdWgN6eMek5xBLwMce7wPfRoLgNp+Zz 3/rWEo+olO9kQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Miklos Szeredi , "Eric W. Biederman" , Sasha Levin , linux-unionfs@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 4/9] ovl: perform vfs_getxattr() with mounter creds Date: Mon, 8 Feb 2021 12:59:41 -0500 Message-Id: <20210208175946.2092374-4-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210208175946.2092374-1-sashal@kernel.org> References: <20210208175946.2092374-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org From: Miklos Szeredi [ Upstream commit 554677b97257b0b69378bd74e521edb7e94769ff ] The vfs_getxattr() in ovl_xattr_set() is used to check whether an xattr exist on a lower layer file that is to be removed. If the xattr does not exist, then no need to copy up the file. This call of vfs_getxattr() wasn't wrapped in credential override, and this is probably okay. But for consitency wrap this instance as well. Reported-by: "Eric W. Biederman" Signed-off-by: Miklos Szeredi Signed-off-by: Sasha Levin --- fs/overlayfs/inode.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 30a1c7fc8c75c..ac6efac119fb9 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -216,7 +216,9 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name, goto out; if (!value && !upperdentry) { + old_cred = ovl_override_creds(dentry->d_sb); err = vfs_getxattr(realdentry, name, NULL, 0); + revert_creds(old_cred); if (err < 0) goto out_drop_write; } -- 2.27.0