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 01B4EC433E6 for ; Mon, 8 Feb 2021 18:05:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C625464DE1 for ; Mon, 8 Feb 2021 18:05:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235406AbhBHSFj (ORCPT ); Mon, 8 Feb 2021 13:05:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:46562 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234926AbhBHSDe (ORCPT ); Mon, 8 Feb 2021 13:03:34 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6976C64EF2; Mon, 8 Feb 2021 17:59:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612807172; bh=YBqvqgp6PAHx6W9ojsyrbRpMv8DrvI2KfiN7xQINXmA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U6ItKUIdNGgapgdPffoxZZLmmChivL6y043UKuL9zWvmNjFXRe0lne6mG5gPRuYWV VWjTCydJEF57ZQ0qXUvU9lU9DMIy/EkXhUxx63YkLfsgWN/W8YyDoiFoA/PcLzhkOM AxcPux4A0xFXelbwI67lAlBsS8bBOhfgN35Nf71Ogyq0P74RfvxMVt/gNsr97ttGwu ObmU4wLazby8BhfwQXfLHVqLpN9XE3yrXcs3dSAgngd9XQqdwqanPhdn6J2O0ngnsd jrdk+Q+m23lmhQ8ATu0BD4ExIZU/hhDdLp5sQ6veTyzPo03MRXzNqkllj+IiTThjqZ GxBVm97Q32EGA== 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 4.19 04/14] ovl: perform vfs_getxattr() with mounter creds Date: Mon, 8 Feb 2021 12:59:16 -0500 Message-Id: <20210208175926.2092211-4-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210208175926.2092211-1-sashal@kernel.org> References: <20210208175926.2092211-1-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 8b3c284ce92ea..08e60a6df77c3 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -340,7 +340,9 @@ 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