From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id p1L8SlhZ136819 for ; Mon, 21 Feb 2011 02:28:47 -0600 Received: from mail-ww0-f41.google.com (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 8C9102EDD5E for ; Mon, 21 Feb 2011 00:31:29 -0800 (PST) Received: from mail-ww0-f41.google.com (mail-ww0-f41.google.com [74.125.82.41]) by cuda.sgi.com with ESMTP id VRdW1qFhrS4FeSuu for ; Mon, 21 Feb 2011 00:31:29 -0800 (PST) Received: by wwi18 with SMTP id 18so2744746wwi.2 for ; Mon, 21 Feb 2011 00:31:29 -0800 (PST) Message-ID: <4D6221B8.9040303@gmail.com> Date: Mon, 21 Feb 2011 09:26:32 +0100 From: Marco Stornelli MIME-Version: 1.0 Subject: [PATCH] Check for immutable flag in fallocate path List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Linux Kernel Cc: cluster-devel@redhat.com, Linux FS Devel , linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, xfs@oss.sgi.com From: Marco Stornelli All fs must check for the immutable flag in their fallocate callback. It's possible to have a race condition in this scenario: an application open a file in read/write and it does something, meanwhile root set the immutable flag on the file, the application at that point can call fallocate with success. Only Ocfs2 check for the immutable flag at the moment. Signed-off-by: Marco Stornelli --- Patch is against 2.6.38-rc5 --- linux-2.6.38-rc5-orig/fs/ext4/extents.c 2011-02-16 04:23:45.000000000 +0100 +++ linux-2.6.38-rc5/fs/ext4/extents.c 2011-02-21 08:43:37.000000000 +0100 @@ -3670,6 +3670,12 @@ long ext4_fallocate(struct file *file, i */ credits = ext4_chunk_trans_blocks(inode, max_blocks); mutex_lock(&inode->i_mutex); + + if (IS_IMMUTABLE(inode)) { + mutex_unlock(&inode->i_mutex); + return -EPERM; + } + ret = inode_newsize_ok(inode, (len + offset)); if (ret) { mutex_unlock(&inode->i_mutex); --- linux-2.6.38-rc5-orig/fs/btrfs/file.c 2011-02-16 04:23:45.000000000 +0100 +++ linux-2.6.38-rc5/fs/btrfs/file.c 2011-02-21 08:55:58.000000000 +0100 @@ -1289,6 +1289,12 @@ static long btrfs_fallocate(struct file btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start); mutex_lock(&inode->i_mutex); + + if (IS_IMMUTABLE(inode)) { + ret = -EPERM; + goto out; + } + ret = inode_newsize_ok(inode, alloc_end); if (ret) goto out; --- linux-2.6.38-rc5-orig/fs/xfs/linux-2.6/xfs_file.c 2011-02-16 04:23:45.000000000 +0100 +++ linux-2.6.38-rc5/fs/xfs/linux-2.6/xfs_file.c 2011-02-21 09:07:46.000000000 +0100 @@ -909,6 +909,11 @@ xfs_file_fallocate( if (mode & FALLOC_FL_PUNCH_HOLE) cmd = XFS_IOC_UNRESVSP; + if (IS_IMMUTABLE(inode)) { + error = -EPERM; + goto out_unlock; + } + /* check the new inode size is valid before allocating */ if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > i_size_read(inode)) { --- linux-2.6.38-rc5-orig/fs/gfs2/file.c 2011-02-16 04:23:45.000000000 +0100 +++ linux-2.6.38-rc5/fs/gfs2/file.c 2011-02-21 09:09:17.000000000 +0100 @@ -797,6 +797,11 @@ static long gfs2_fallocate(struct file * if (unlikely(error)) goto out_uninit; + if (IS_IMMUTABLE(inode)) { + error = -EPERM; + goto out_unlock; + } + if (!gfs2_write_alloc_required(ip, offset, len)) goto out_unlock; _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs