From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: [RFC][PATCH 13/27] sys_linkat(): elevate write count around vfs_link() Date: Wed, 07 Jun 2006 17:10:24 -0700 Message-ID: <20060608001024.A08D2781@localhost.localdomain> References: <20060608001013.0D041507@localhost.localdomain> Cc: herbert@13thfloor.at, viro@ftp.linux.org.uk, hch@infradead.org, trond.myklebust@fys.uio.no, Dave Hansen Return-path: Received: from e5.ny.us.ibm.com ([32.97.182.145]:42970 "EHLO e5.ny.us.ibm.com") by vger.kernel.org with ESMTP id S932493AbWFHAKe (ORCPT ); Wed, 7 Jun 2006 20:10:34 -0400 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e5.ny.us.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id k580AULb013691 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 7 Jun 2006 20:10:31 -0400 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay02.pok.ibm.com (8.13.6/NCO/VER7.0) with ESMTP id k580ATGu266678 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 7 Jun 2006 20:10:29 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id k580ASWd005023 for ; Wed, 7 Jun 2006 20:10:29 -0400 To: linux-fsdevel@vger.kernel.org In-Reply-To: <20060608001013.0D041507@localhost.localdomain> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Signed-off-by: Dave Hansen --- lxc-dave/fs/namei.c | 14 ++++++++++---- 1 files changed, 10 insertions(+), 4 deletions(-) diff -puN fs/namei.c~elevate-writers-vfs_link-part1 fs/namei.c --- lxc/fs/namei.c~elevate-writers-vfs_link-part1 2006-06-07 16:53:19.000000000 -0700 +++ lxc-dave/fs/namei.c 2006-06-07 16:53:19.000000000 -0700 @@ -2285,10 +2285,16 @@ asmlinkage long sys_linkat(int olddfd, c goto out_release; new_dentry = lookup_create(&nd, 0); error = PTR_ERR(new_dentry); - if (!IS_ERR(new_dentry)) { - error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry); - dput(new_dentry); - } + if (IS_ERR(new_dentry)) + goto out_unlock; + error = mnt_want_write(nd.mnt); + if (error) + goto out_dput; + error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry); + mnt_drop_write(nd.mnt); +out_dput: + dput(new_dentry); +out_unlock: mutex_unlock(&nd.dentry->d_inode->i_mutex); out_release: path_release(&nd); _