From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754977Ab1A2TJA (ORCPT ); Sat, 29 Jan 2011 14:09:00 -0500 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:49506 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754878Ab1A2TIr (ORCPT ); Sat, 29 Jan 2011 14:08:47 -0500 From: "Aneesh Kumar K.V" To: hch@infradead.org, viro@zeniv.linux.org.uk, adilger@sun.com, corbet@lwn.net, neilb@suse.de, npiggin@kernel.dk, hooanon05@yahoo.co.jp, bfields@fieldses.org, miklos@szeredi.hu Cc: linux-fsdevel@vger.kernel.org, sfrench@us.ibm.com, philippe.deniel@CEA.FR, linux-kernel@vger.kernel.org, "Aneesh Kumar K.V" Subject: [PATCH -V26 04/16] fs: Don't allow to create hardlink for deleted file Date: Sun, 30 Jan 2011 00:38:07 +0530 Message-Id: <1296328099-23263-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1296328099-23263-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1296328099-23263-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add inode->i_nlink == 0 check in VFS. Some of the file systems do this internally. A followup patch will remove those instance. This is needed to ensure that with link by handle we don't allow to create hardlink of an unlinked file. The check also prevent a race between unlink and link Signed-off-by: Aneesh Kumar K.V --- fs/namei.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 6b0536f..a8346fa 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3318,7 +3318,11 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de return error; mutex_lock(&inode->i_mutex); - error = dir->i_op->link(old_dentry, dir, new_dentry); + /* Make sure we don't allow creating hardlink to an unlinked file */ + if (inode->i_nlink == 0) + error = -ENOENT; + else + error = dir->i_op->link(old_dentry, dir, new_dentry); mutex_unlock(&inode->i_mutex); if (!error) fsnotify_link(dir, inode, new_dentry); -- 1.7.1