From: Aneesh Kumar K.V Date: Sat, 29 Jan 2011 13:13:27 +0000 (+0530) Subject: fs: Don't allow to create hardlink for deleted file X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=aae8a97d3ec30788790d1720b71d76fd8eb44b73;p=openwrt%2Fstaging%2Fblogic.git fs: Don't allow to create hardlink for deleted file 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 Signed-off-by: Al Viro --- diff --git a/fs/namei.c b/fs/namei.c index 83e92bab79a6..33be51a2ddb7 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2906,7 +2906,11 @@ 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);