From: Dave Hansen <haveblue@us.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org, herbert@13thfloor.at,
viro@ftp.linux.org.uk, Dave Hansen <haveblue@us.ibm.com>
Subject: [RFC][PATCH 16/20] sys_mknodat(): elevate write count for vfs_mknod/create()
Date: Fri, 16 Jun 2006 16:12:25 -0700 [thread overview]
Message-ID: <20060616231225.68636C81@localhost.localdomain> (raw)
In-Reply-To: <20060616231213.D4C5D6AF@localhost.localdomain>
This takes care of all of the direct callers of vfs_mknod().
Since a few of these cases also handle normal file creation
as well, this also covers some calls to vfs_create().
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
---
lxc-dave/fs/namei.c | 12 ++++++++++++
lxc-dave/fs/nfsd/vfs.c | 4 ++++
lxc-dave/net/unix/af_unix.c | 4 ++++
3 files changed, 20 insertions(+)
diff -puN fs/namei.c~C-elevate-writers-vfs_mknod-try2 fs/namei.c
--- lxc/fs/namei.c~C-elevate-writers-vfs_mknod-try2 2006-06-16 15:58:09.000000000 -0700
+++ lxc-dave/fs/namei.c 2006-06-16 15:58:09.000000000 -0700
@@ -1857,14 +1857,26 @@ asmlinkage long sys_mknodat(int dfd, con
if (!IS_ERR(dentry)) {
switch (mode & S_IFMT) {
case 0: case S_IFREG:
+ error = mnt_want_write(nd.mnt);
+ if (error)
+ break;
error = vfs_create(nd.dentry->d_inode,dentry,mode,&nd);
+ mnt_drop_write(nd.mnt);
break;
case S_IFCHR: case S_IFBLK:
+ error = mnt_want_write(nd.mnt);
+ if (error)
+ break;
error = vfs_mknod(nd.dentry->d_inode,dentry,mode,
new_decode_dev(dev));
+ mnt_drop_write(nd.mnt);
break;
case S_IFIFO: case S_IFSOCK:
+ error = mnt_want_write(nd.mnt);
+ if (error)
+ break;
error = vfs_mknod(nd.dentry->d_inode,dentry,mode,0);
+ mnt_drop_write(nd.mnt);
break;
case S_IFDIR:
error = -EPERM;
diff -puN fs/nfsd/vfs.c~C-elevate-writers-vfs_mknod-try2 fs/nfsd/vfs.c
--- lxc/fs/nfsd/vfs.c~C-elevate-writers-vfs_mknod-try2 2006-06-16 15:58:09.000000000 -0700
+++ lxc-dave/fs/nfsd/vfs.c 2006-06-16 15:58:09.000000000 -0700
@@ -1153,6 +1153,9 @@ nfsd_create(struct svc_rqst *rqstp, stru
/*
* Get the dir op function pointer.
*/
+ err = mnt_want_write(fhp->fh_export->ex_mnt);
+ if (err)
+ goto out_nfserr;
err = nfserr_perm;
switch (type) {
case S_IFREG:
@@ -1171,6 +1174,7 @@ nfsd_create(struct svc_rqst *rqstp, stru
printk("nfsd: bad file type %o in nfsd_create\n", type);
err = -EINVAL;
}
+ mnt_drop_write(fhp->fh_export->ex_mnt);
if (err < 0)
goto out_nfserr;
diff -puN net/unix/af_unix.c~C-elevate-writers-vfs_mknod-try2 net/unix/af_unix.c
--- lxc/net/unix/af_unix.c~C-elevate-writers-vfs_mknod-try2 2006-06-16 15:58:09.000000000 -0700
+++ lxc-dave/net/unix/af_unix.c 2006-06-16 15:58:09.000000000 -0700
@@ -789,7 +789,11 @@ static int unix_bind(struct socket *sock
*/
mode = S_IFSOCK |
(SOCK_INODE(sock)->i_mode & ~current->fs->umask);
+ err = mnt_want_write(nd.mnt);
+ if (err)
+ goto out_mknod_dput;
err = vfs_mknod(nd.dentry->d_inode, dentry, mode, 0);
+ mnt_drop_write(nd.mnt);
if (err)
goto out_mknod_dput;
mutex_unlock(&nd.dentry->d_inode->i_mutex);
_
next prev parent reply other threads:[~2006-06-16 23:12 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-06-16 23:12 [RFC][PATCH 00/20] Mount writer count and read-only bind mounts (v2) Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 01/20] prepare for write access checks: collapse if() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 02/20] r/o bind mount prepwork: move open_namei()'s vfs_create() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 03/20] Add vfsmount writer count Dave Hansen
2006-06-18 18:33 ` Al Viro
2006-06-19 17:02 ` Dave Hansen
2006-06-20 21:20 ` Al Viro
2006-06-22 17:01 ` Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 04/20] elevate mnt writers for callers of vfs_mkdir() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 05/20] elevate write count during entire ncp_ioctl() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 07/20] elevate mount count for extended attributes Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 06/20] sys_symlinkat() elevate write count around vfs_symlink() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 08/20] sys_linkat(): elevate write count around vfs_link() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 09/20] mount_is_safe(): add comment Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 10/20] unix_find_other() elevate write count for touch_atime() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 11/20] elevate write count over calls to vfs_rename() Dave Hansen
2006-06-18 18:23 ` Al Viro
2006-06-19 17:18 ` Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 12/20] tricky: elevate write count files are open()ed Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 13/20] elevate writer count for do_sys_truncate() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 14/20] elevate write count for do_utimes() Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 15/20] elevate write count for do_sys_utime() and touch_atime() Dave Hansen
2006-06-16 23:12 ` Dave Hansen [this message]
2006-06-16 23:12 ` [RFC][PATCH 17/20] elevate mnt writers for vfs_unlink() callers Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 18/20] do_rmdir(): elevate write count Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 19/20] elevate writer count for custom 'struct file' Dave Hansen
2006-06-16 23:12 ` [RFC][PATCH 20/20] honor r/w changes at do_remount() time Dave Hansen
2006-06-18 18:36 ` Al Viro
2006-06-19 16:45 ` Dave Hansen
2006-06-16 23:29 ` [RFC][PATCH 00/20] Mount writer count and read-only bind mounts (v2) Grzegorz Kulewski
2006-06-16 23:41 ` Dave Hansen
2006-06-17 0:10 ` Grzegorz Kulewski
2006-06-17 3:35 ` Herbert Poetzl
2006-06-17 9:36 ` Jan Engelhardt
2006-06-17 13:29 ` Herbert Poetzl
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