From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932524Ab0FYTIP (ORCPT ); Fri, 25 Jun 2010 15:08:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:20659 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932490Ab0FYTH0 (ORCPT ); Fri, 25 Jun 2010 15:07:26 -0400 From: Valerie Aurora To: Alexander Viro Cc: Miklos Szeredi , Jan Blunck , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Valerie Aurora Subject: [PATCH 33/38] union-mount: Implement union-aware truncate() Date: Fri, 25 Jun 2010 12:05:23 -0700 Message-Id: <1277492728-11446-34-git-send-email-vaurora@redhat.com> In-Reply-To: <1277492728-11446-1-git-send-email-vaurora@redhat.com> References: <1277492728-11446-1-git-send-email-vaurora@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --- fs/open.c | 24 ++++++++++++++++++++---- 1 files changed, 20 insertions(+), 4 deletions(-) diff --git a/fs/open.c b/fs/open.c index 68c97dd..3c1ae55 100644 --- a/fs/open.c +++ b/fs/open.c @@ -230,14 +230,17 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, static long do_sys_truncate(const char __user *pathname, loff_t length) { struct path path; + struct nameidata nd; + struct vfsmount *mnt; struct inode *inode; + char *tmp; int error; error = -EINVAL; if (length < 0) /* sorry, but loff_t says... */ goto out; - error = user_path(pathname, &path); + error = user_path_nd(AT_FDCWD, pathname, 0, &nd, &path, &tmp); if (error) goto out; inode = path.dentry->d_inode; @@ -251,11 +254,16 @@ static long do_sys_truncate(const char __user *pathname, loff_t length) if (!S_ISREG(inode->i_mode)) goto dput_and_out; - error = mnt_want_write(path.mnt); + if (IS_DIR_UNIONED(nd.path.dentry)) + mnt = nd.path.mnt; + else + mnt = path.mnt; + + error = mnt_want_write(mnt); if (error) goto dput_and_out; - error = inode_permission(inode, MAY_WRITE); + error = path_permission(&path, &nd.path, MAY_WRITE); if (error) goto mnt_drop_write_and_out; @@ -263,6 +271,12 @@ static long do_sys_truncate(const char __user *pathname, loff_t length) if (IS_APPEND(inode)) goto mnt_drop_write_and_out; + error = union_copyup_len(&nd, &path, length); + if (error) + goto mnt_drop_write_and_out; + + /* path may have changed after copyup */ + inode = path.dentry->d_inode; error = get_write_access(inode); if (error) goto mnt_drop_write_and_out; @@ -284,9 +298,11 @@ static long do_sys_truncate(const char __user *pathname, loff_t length) put_write_and_out: put_write_access(inode); mnt_drop_write_and_out: - mnt_drop_write(path.mnt); + mnt_drop_write(mnt); dput_and_out: path_put(&path); + path_put(&nd.path); + putname(tmp); out: return error; } -- 1.6.3.3