linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dave Hansen <haveblue@us.ibm.com>
To: akpm@osdl.org
Cc: linux-kernel@vger.kernel.org, hch@infradead.org,
	Dave Hansen <haveblue@us.ibm.com>
Subject: [PATCH 11/25] elevate write count during entire ncp_ioctl()
Date: Thu, 20 Sep 2007 12:53:02 -0700	[thread overview]
Message-ID: <20070920195302.ACDE8A3E@kernel> (raw)
In-Reply-To: <20070920195249.852667D5@kernel>


Some ioctls need write access, but others don't.  Make a helper
function to decide when write access is needed, and take it.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
---

 lxc-dave/fs/ncpfs/ioctl.c |   54 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 53 insertions(+), 1 deletion(-)

diff -puN fs/ncpfs/ioctl.c~elevate-write-count-during-entire-ncp-ioctl fs/ncpfs/ioctl.c
--- lxc/fs/ncpfs/ioctl.c~elevate-write-count-during-entire-ncp-ioctl	2007-09-20 12:16:15.000000000 -0700
+++ lxc-dave/fs/ncpfs/ioctl.c	2007-09-20 12:16:15.000000000 -0700
@@ -14,6 +14,7 @@
 #include <linux/ioctl.h>
 #include <linux/time.h>
 #include <linux/mm.h>
+#include <linux/mount.h>
 #include <linux/highuid.h>
 #include <linux/smp_lock.h>
 #include <linux/vmalloc.h>
@@ -261,7 +262,7 @@ ncp_get_charsets(struct ncp_server* serv
 }
 #endif /* CONFIG_NCPFS_NLS */
 
-int ncp_ioctl(struct inode *inode, struct file *filp,
+static int __ncp_ioctl(struct inode *inode, struct file *filp,
 	      unsigned int cmd, unsigned long arg)
 {
 	struct ncp_server *server = NCP_SERVER(inode);
@@ -822,6 +823,57 @@ outrel:			
 	return -EINVAL;
 }
 
+static int ncp_ioctl_need_write(unsigned int cmd)
+{
+	switch (cmd) {
+	case NCP_IOC_GET_FS_INFO:
+	case NCP_IOC_GET_FS_INFO_V2:
+	case NCP_IOC_NCPREQUEST:
+	case NCP_IOC_SETDENTRYTTL:
+	case NCP_IOC_SIGN_INIT:
+	case NCP_IOC_LOCKUNLOCK:
+	case NCP_IOC_SET_SIGN_WANTED:
+		return 1;
+	case NCP_IOC_GETOBJECTNAME:
+	case NCP_IOC_SETOBJECTNAME:
+	case NCP_IOC_GETPRIVATEDATA:
+	case NCP_IOC_SETPRIVATEDATA:
+	case NCP_IOC_SETCHARSETS:
+	case NCP_IOC_GETCHARSETS:
+	case NCP_IOC_CONN_LOGGED_IN:
+	case NCP_IOC_GETDENTRYTTL:
+	case NCP_IOC_GETMOUNTUID2:
+	case NCP_IOC_SIGN_WANTED:
+	case NCP_IOC_GETROOT:
+	case NCP_IOC_SETROOT:
+		return 0;
+	default:
+		/* unkown IOCTL command, assume write */
+	}
+	return 1;
+}
+
+int ncp_ioctl(struct inode *inode, struct file *filp,
+	      unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	if (ncp_ioctl_need_write(cmd)) {
+		/*
+		 * inside the ioctl(), any failures which
+		 * are because of file_permission() are
+		 * -EACCESS, so it seems consistent to keep
+		 *  that here.
+		 */
+		if (mnt_want_write(filp->f_vfsmnt))
+			return -EACCES;
+	}
+	ret = __ncp_ioctl(inode, filp, cmd, arg);
+	if (ncp_ioctl_need_write(cmd))
+		mnt_drop_write(filp->f_vfsmnt);
+	return ret;
+}
+
 #ifdef CONFIG_COMPAT
 long ncp_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
_

  parent reply	other threads:[~2007-09-20 19:55 UTC|newest]

Thread overview: 48+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-20 19:52 [PATCH 00/25] Read-only bind mounts Dave Hansen
2007-09-20 19:52 ` [PATCH 01/25] filesystem helpers for custom 'struct file's Dave Hansen
2007-09-20 19:52 ` [PATCH 02/25] rearrange may_open() to be r/o friendly Dave Hansen
2007-09-20 19:52 ` [PATCH 03/25] give may_open() a local 'mnt' variable Dave Hansen
2007-09-20 19:57   ` Christoph Hellwig
2007-09-20 19:52 ` [PATCH 04/25] create cleanup helper svc_msnfs() Dave Hansen
2007-09-20 19:52 ` [PATCH 05/25] r/o bind mounts: stub functions Dave Hansen
2007-09-20 19:52 ` [PATCH 06/25] elevate write count open()'d files Dave Hansen
2007-11-28  8:41   ` Andrew Morton
2007-11-28 17:33     ` Dave Hansen
2007-09-20 19:52 ` [PATCH 07/25] r/o bind mounts: elevate write count for some ioctls Dave Hansen
2007-09-21  8:17   ` Andrew Morton
2007-09-21 21:15     ` Dave Hansen
2007-09-26  1:34     ` [RFC] detect missed mnt_want_write() calls Dave Hansen
2007-09-21 23:03   ` [PATCH 07/25] r/o bind mounts: elevate write count for some ioctls Andrew Morton
2007-09-21 23:39     ` Dave Hansen
2007-09-21 23:47       ` Andrew Morton
2007-09-20 19:52 ` [PATCH 08/25] elevate writer count for chown and friends Dave Hansen
2007-09-20 19:53 ` [PATCH 09/25] make access() use mnt check Dave Hansen
2007-09-20 19:53 ` [PATCH 10/25] elevate mnt writers for callers of vfs_mkdir() Dave Hansen
2007-09-20 19:53 ` Dave Hansen [this message]
2007-09-20 19:53 ` [PATCH 12/25] elevate write count for link and symlink calls Dave Hansen
2007-09-20 19:53 ` [PATCH 13/25] elevate mount count for extended attributes Dave Hansen
2007-09-20 19:53 ` [PATCH 14/25] elevate write count for file_update_time() Dave Hansen
2007-09-20 19:53 ` [PATCH 15/25] unix_find_other() elevate write count for touch_atime() Dave Hansen
2007-09-20 19:53 ` [PATCH 16/25] elevate write count over calls to vfs_rename() Dave Hansen
2007-09-20 19:53 ` [PATCH 17/25] nfs: check mnt instead of superblock directly Dave Hansen
2007-09-20 19:53 ` [PATCH 18/25] elevate writer count for do_sys_truncate() Dave Hansen
2007-09-20 19:53 ` [PATCH 19/25] elevate write count for do_utimes() Dave Hansen
2007-09-20 19:53 ` [PATCH 20/25] elevate write count for do_sys_utime() and touch_atime() Dave Hansen
2007-09-20 19:53 ` [PATCH 21/25] sys_mknodat(): elevate write count for vfs_mknod/create() Dave Hansen
2007-09-20 19:53 ` [PATCH 22/25] elevate mnt writers for vfs_unlink() callers Dave Hansen
2007-09-20 19:53 ` [PATCH 23/25] do_rmdir(): elevate write count Dave Hansen
2007-09-20 19:53 ` [PATCH 24/25] r/o bind mounts: track number of mount writers Dave Hansen
2007-09-24  6:17   ` Andrew Morton
2007-09-24 14:34     ` Arjan van de Ven
2007-09-24 22:06     ` Dave Hansen
2007-09-24 22:25       ` Andrew Morton
2007-09-24 23:05         ` Dave Hansen
2007-09-24 23:15           ` Andrew Morton
2007-09-25 16:10             ` Dave Hansen
2007-09-24 17:54   ` Christoph Hellwig
2007-09-24 19:10     ` Andrew Morton
2007-09-24 19:24       ` Christoph Hellwig
2007-09-24 19:28     ` Dave Hansen
2007-09-24 19:42       ` Andrew Morton
2007-10-01 18:06         ` Dave Hansen
2007-09-20 19:53 ` [PATCH 25/25] honor r/w changes at do_remount() time Dave Hansen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20070920195302.ACDE8A3E@kernel \
    --to=haveblue@us.ibm.com \
    --cc=akpm@osdl.org \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).