Re: [PATCH] cifs: use standard token parser for mount options

[Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On Wed, 2012-03-21 at 13:38 -0400, Jeff Layton wrote:
> On Fri, 09 Mar 2012 15:33:17 +0000
> Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> 
> > Use the standard token parser instead of the long if confidtion to parse
> > cifs mount options.
> > 
> > This was first proposed by Scott Lovenberg
> > http://lists.samba.org/archive/linux-cifs-client/2010-May/006079.html
> > 
> > Mount options have been grouped together in terms of their input types.
> > Aliases for username, password, domain and credentials have been added.
> > The password parser has been modified to make it easier to read.
> > 
> > Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> > 
> 
> 
> In testing this today, I found a problem. I tried to mount up a share
> with sec=none as the options. With that, I got this error:
> 
>     CIFS: Unknown mount option pass=
> 
> The problem is that the mount.cifs helper will pass a blank "pass="
> option to the kernel. It seems like the standard option parser doesn't
> have a way to allow you to specify an optional argument. That may need
> to be added in order for this to work.


We could use it in this manner.

----
Allow mount option pass to be a blank value.

When using sec=none, the mount.cifs helper will pass a blank 'pass='
mount option. This should be handled by the parser.

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/connect.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 8f83ea0..831f242 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -107,6 +107,9 @@ enum {
 	/* Mount options to be ignored */
 	Opt_ignore,
 
+	/* Options which could be blank */
+	Opt_blank_pass,
+
 	Opt_err
 };
 
@@ -180,6 +183,7 @@ static const match_table_t cifs_mount_option_tokens = {
 
 	{ Opt_user, "user=%s" },
 	{ Opt_user, "username=%s" },
+	{ Opt_blank_pass, "pass=" },
 	{ Opt_pass, "pass=%s" },
 	{ Opt_pass, "password=%s" },
 	{ Opt_ip, "ip=%s" },
@@ -1546,6 +1550,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 			}
 			vol->nullauth = 0;
 			break;
+		case Opt_blank_pass:
+			vol->password = NULL;
+			break;
 		case Opt_pass:
 			/* passwords have to be handled differently
 			 * to allow the character used for deliminator
-- 
1.7.7.6