Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764120AbYBOWt2 (ORCPT ); Fri, 15 Feb 2008 17:49:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932107AbYBOWiD (ORCPT ); Fri, 15 Feb 2008 17:38:03 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.141]:36210 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765572AbYBOWhx (ORCPT ); Fri, 15 Feb 2008 17:37:53 -0500 Subject: [PATCH 21/30] r/o bind mounts: get write access for vfs_rename() callers To: linux-kernel@vger.kernel.org Cc: hch@lst.de, miklos@szeredi.hu, akpm@osdl.org, Dave Hansen From: Dave Hansen Date: Fri, 15 Feb 2008 14:37:49 -0800 References: <20080215223721.9E0A088A@kernel> In-Reply-To: <20080215223721.9E0A088A@kernel> Message-Id: <20080215223749.E8D2C121@kernel> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2581 Lines: 73 This also uses the little helper in the NFS code to make an if() a little bit less ugly. We introduced the helper at the beginning of the series. Acked-by: Al Viro Signed-off-by: Christoph Hellwig Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton --- linux-2.6.git-dave/fs/namei.c | 4 ++++ linux-2.6.git-dave/fs/nfsd/vfs.c | 17 +++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff -puN fs/namei.c~r-o-bind-mounts-elevate-write-count-over-calls-to-vfs_rename fs/namei.c --- linux-2.6.git/fs/namei.c~r-o-bind-mounts-elevate-write-count-over-calls-to-vfs_rename 2008-02-15 13:25:54.000000000 -0800 +++ linux-2.6.git-dave/fs/namei.c 2008-02-15 13:25:54.000000000 -0800 @@ -2751,8 +2751,12 @@ static int do_rename(int olddfd, const c if (new_dentry == trap) goto exit5; + error = mnt_want_write(oldnd.path.mnt); + if (error) + goto exit5; error = vfs_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, new_dentry); + mnt_drop_write(oldnd.path.mnt); exit5: dput(new_dentry); exit4: diff -puN fs/nfsd/vfs.c~r-o-bind-mounts-elevate-write-count-over-calls-to-vfs_rename fs/nfsd/vfs.c --- linux-2.6.git/fs/nfsd/vfs.c~r-o-bind-mounts-elevate-write-count-over-calls-to-vfs_rename 2008-02-15 13:25:54.000000000 -0800 +++ linux-2.6.git-dave/fs/nfsd/vfs.c 2008-02-15 13:25:54.000000000 -0800 @@ -1678,13 +1678,20 @@ nfsd_rename(struct svc_rqst *rqstp, stru if (ndentry == trap) goto out_dput_new; -#ifdef MSNFS - if ((ffhp->fh_export->ex_flags & NFSEXP_MSNFS) && + if (svc_msnfs(ffhp) && ((atomic_read(&odentry->d_count) > 1) || (atomic_read(&ndentry->d_count) > 1))) { host_err = -EPERM; - } else -#endif + goto out_dput_new; + } + + host_err = -EXDEV; + if (ffhp->fh_export->ex_mnt != tfhp->fh_export->ex_mnt) + goto out_dput_new; + host_err = mnt_want_write(ffhp->fh_export->ex_mnt); + if (host_err) + goto out_dput_new; + host_err = vfs_rename(fdir, odentry, tdir, ndentry); if (!host_err && EX_ISSYNC(tfhp->fh_export)) { host_err = nfsd_sync_dir(tdentry); @@ -1692,6 +1699,8 @@ nfsd_rename(struct svc_rqst *rqstp, stru host_err = nfsd_sync_dir(fdentry); } + mnt_drop_write(ffhp->fh_export->ex_mnt); + out_dput_new: dput(ndentry); out_dput_old: _ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/