Issue with upgrade to kernel 3.4.10 -> invalid argument error

Issue with upgrade to kernel 3.4.10 -> invalid argument error

[Federico Sauter]

[-- Attachment #1: Type: text/plain, Size: 2495 bytes --]

Greetings,


I am having an issue mounting CIFS shares since we upgraded our Linux 
kernel from 2.6.27 to 3.4.10. Each time I try to mount a share drive I 
get an "Invalid argument" error message even though I am using the same 
command line that had previously worked, e.g.:

mount -t cifs //172.16.1.10/allusers /mnt/TEST -o 
'ro,user=cifs,password=secret

I went ahead and checked the source code, and found out that the 
following condition did not evaluate to true:

fs/cifs/connect.c:2130
	if (volume_info->UNCip && volume_info->UNC)
	{
         	rc = cifs_fill_sockaddr((struct sockaddr *)&addr,
                 	    volume_info->UNCip,
	                    strlen(volume_info->UNCip),
         	            volume_info->port);

Thus I obtained a kernel message "Connecting to DFS root not implemented 
yet." So I am now explicitly specifying the UNC as an option, as well as 
the device name:

mount -t cifs //172.16.1.10/allusers /mnt/TEST -o 
'ro,user=cifs,password=secret,unc=\\172.16.1.10\allusers'

Question #1: Why do I have to explicitly provide the UNC now?

It almost seem like a bug to me, given that the devname parameter to the 
cifs_parse_mount_options function already contains this information. The 
newest sources for the 3.7-rc1 kernel seem to have no changes in this 
regard (even though I just took a *quick* look at those sources.)

If this is a bug I would be glad to provide a patch to fix it.

The second observation that I made concerned specifying the UNC as an 
option and passing in slashes as separators instead of backslashes:

mount -t cifs //172.16.1.10/allusers /mnt/TEST -o 
'ro,user=cifs,password=secret,unc=//172.16.1.10/allusers'

This also results in an invalid argument error, as the parser does not 
convert all slashes into backslashes (for the unc option, as the devname 
parameter is already converted!), and thus extract_hostname is not able 
to function properly.

Question #2: Should this be considered a bug?

If that is the case, I would like to suggest the attached bugfix.

Please let me know what you think and thank you in advance for your kind 
support!


Best regards,


-- 
Federico Sauter / Senior firmware programmer
Innominate Security Technologies AG / protecting industrial networks
tel: +49.30.921028-210 / fax: +49.30.921028-020
Rudower Chaussee 13 / D-12489 Berlin / http://www.innominate.com/

Register Court: AG Charlottenburg, HR B 81603
Management Board: Dirk Seewald
Chairman of the Supervisory Board: Christoph Leifer

[-- Attachment #2: connect.patch --]
[-- Type: text/x-patch, Size: 834 bytes --]

--- fs/cifs/connect.c.stable	2012-10-16 16:44:50.000000000 +0200
+++ fs/cifs/connect.c.fixed	2012-10-16 18:56:37.000000000 +0200
@@ -1204,6 +1204,7 @@
 	char *string = NULL;
 	char *tmp_end, *value;
 	char delim;
+	char *p, *q;
 
 	separator[0] = ',';
 	separator[1] = 0;
@@ -1662,12 +1663,12 @@
 				printk(KERN_WARNING "CIFS: no memory for UNC\n");
 				goto cifs_parse_mount_err;
 			}
-			strcpy(vol->UNC, string);
 
-			if (strncmp(string, "//", 2) == 0) {
-				vol->UNC[0] = '\\';
-				vol->UNC[1] = '\\';
-			} else if (strncmp(string, "\\\\", 2) != 0) {
+			for (p = string, q = vol->UNC; *p; ++p, ++q) {
+				*q = *p == '/'? '\\' : *p;
+			}
+			*q = '\0';
+			if (strncmp(vol->UNC, "\\\\", 2) != 0) {
 				printk(KERN_WARNING "CIFS: UNC Path does not "
 						    "begin with // or \\\\\n");
 				goto cifs_parse_mount_err;

Fwd: Issue with upgrade to kernel 3.4.10 -> invalid argument error

[Steve French]

Why the ' (apostrophes) around the arguments to -o ?

What version of mount.cifs ("/sbin/mount.cifs -V" will display it) are you
using?


On Tue, Oct 16, 2012 at 12:03 PM, Federico Sauter <fsauter-LVkJPw3T+odGBRGhe+f61g@public.gmane.org>
wrote:
>
> Greetings,
>
>
> I am having an issue mounting CIFS shares since we upgraded our Linux
> kernel from 2.6.27 to 3.4.10. Each time I try to mount a share drive I get
> an "Invalid argument" error message even though I am using the same command
> line that had previously worked, e.g.:
>
> mount -t cifs //172.16.1.10/allusers /mnt/TEST -o
> 'ro,user=cifs,password=secret
>
> I went ahead and checked the source code, and found out that the following
> condition did not evaluate to true:
>
> fs/cifs/connect.c:2130
>         if (volume_info->UNCip && volume_info->UNC)
>         {
>                 rc = cifs_fill_sockaddr((struct sockaddr *)&addr,
>                             volume_info->UNCip,
>                             strlen(volume_info->UNCip),
>                             volume_info->port);
>
> Thus I obtained a kernel message "Connecting to DFS root not implemented
> yet." So I am now explicitly specifying the UNC as an option, as well as the
> device name:
>
> mount -t cifs //172.16.1.10/allusers /mnt/TEST -o
> 'ro,user=cifs,password=secret,unc=\\172.16.1.10\allusers'
>
> Question #1: Why do I have to explicitly provide the UNC now?
>
> It almost seem like a bug to me, given that the devname parameter to the
> cifs_parse_mount_options function already contains this information. The
> newest sources for the 3.7-rc1 kernel seem to have no changes in this regard
> (even though I just took a *quick* look at those sources.)
>
> If this is a bug I would be glad to provide a patch to fix it.
>
> The second observation that I made concerned specifying the UNC as an
> option and passing in slashes as separators instead of backslashes:
>
> mount -t cifs //172.16.1.10/allusers /mnt/TEST -o
> 'ro,user=cifs,password=secret,unc=//172.16.1.10/allusers'
>
> This also results in an invalid argument error, as the parser does not
> convert all slashes into backslashes (for the unc option, as the devname
> parameter is already converted!), and thus extract_hostname is not able to
> function properly.
>
> Question #2: Should this be considered a bug?
>
> If that is the case, I would like to suggest the attached bugfix.
>
> Please let me know what you think and thank you in advance for your kind
> support!
>
>
> Best regards,
>
>
> --
> Federico Sauter / Senior firmware programmer
> Innominate Security Technologies AG / protecting industrial networks
> tel: +49.30.921028-210 / fax: +49.30.921028-020
> Rudower Chaussee 13 / D-12489 Berlin / http://www.innominate.com/
>
> Register Court: AG Charlottenburg, HR B 81603
> Management Board: Dirk Seewald
> Chairman of the Supervisory Board: Christoph Leifer




--
Thanks,

Steve



--
Thanks,

Steve

Re: Issue with upgrade to kernel 3.4.10 -> invalid argument error

[Suresh Jayaraman]

On 10/16/2012 10:33 PM, Federico Sauter wrote:
> Greetings,
> 
> 
> I am having an issue mounting CIFS shares since we upgraded our Linux
> kernel from 2.6.27 to 3.4.10. Each time I try to mount a share drive I
> get an "Invalid argument" error message even though I am using the same
> command line that had previously worked, e.g.:
> 

A quick look suggests that the symptom is similar to the one fixed by
the below commit

commit e73f843a3235a19de38359c91586e9eadef12238
Author: Suresh Jayaraman <sjayaraman-IBi9RG/b67k@public.gmane.org>
Date:   Tue Jun 12 07:15:50 2012 +0530

    cifs: fix parsing of password mount option


It might be worth trying to see whether the commit fixes the problem you
are seeing.


Thanks
Suresh

Re: Issue with upgrade to kernel 3.4.10 -> invalid argument error

[Federico Sauter]

Hello Steve,

I use the apostrophes just to avoid escaping backslashes when I use them.

Thank you very much for your question, since it led me to solve my 
problem. I was using a different mount version (busybox) and now that 
you pointed me in the right direction I found the issue by comparing the 
mount.cifs source code and the busybox sources and making the 
appropriate fixes.

Kind regards,

Fred


On 10/16/2012 08:46 PM, Steve French wrote:
> Why the ' (apostrophes) around the arguments to -o ?
>
> What version of mount.cifs ("/sbin/mount.cifs -V" will display it) are
> you using?
>
> On Tue, Oct 16, 2012 at 12:03 PM, Federico Sauter
> <fsauter-LVkJPw3T+odGBRGhe+f61g@public.gmane.org <mailto:fsauter-LVkJPw3T+odGBRGhe+f61g@public.gmane.org>> wrote:
>
>     Greetings,
>
>
>     I am having an issue mounting CIFS shares since we upgraded our
>     Linux kernel from 2.6.27 to 3.4.10. Each time I try to mount a share
>     drive I get an "Invalid argument" error message even though I am
>     using the same command line that had previously worked, e.g.:
>
>     mount -t cifs //172.16.1.10/allusers <http://172.16.1.10/allusers>
>     /mnt/TEST -o 'ro,user=cifs,password=secret
>
>     I went ahead and checked the source code, and found out that the
>     following condition did not evaluate to true:
>
>     fs/cifs/connect.c:2130
>              if (volume_info->UNCip && volume_info->UNC)
>              {
>                      rc = cifs_fill_sockaddr((struct sockaddr *)&addr,
>                                  volume_info->UNCip,
>                                  strlen(volume_info->UNCip),
>                                  volume_info->port);
>
>     Thus I obtained a kernel message "Connecting to DFS root not
>     implemented yet." So I am now explicitly specifying the UNC as an
>     option, as well as the device name:
>
>     mount -t cifs //172.16.1.10/allusers <http://172.16.1.10/allusers>
>     /mnt/TEST -o 'ro,user=cifs,password=secret,__unc=\\172.16.1.10\allusers'
>
>     Question #1: Why do I have to explicitly provide the UNC now?
>
>     It almost seem like a bug to me, given that the devname parameter to
>     the cifs_parse_mount_options function already contains this
>     information. The newest sources for the 3.7-rc1 kernel seem to have
>     no changes in this regard (even though I just took a *quick* look at
>     those sources.)
>
>     If this is a bug I would be glad to provide a patch to fix it.
>
>     The second observation that I made concerned specifying the UNC as
>     an option and passing in slashes as separators instead of backslashes:
>
>     mount -t cifs //172.16.1.10/allusers <http://172.16.1.10/allusers>
>     /mnt/TEST -o
>     'ro,user=cifs,password=secret,__unc=//172.16.1.10/allusers
>     <http://172.16.1.10/allusers>'
>
>     This also results in an invalid argument error, as the parser does
>     not convert all slashes into backslashes (for the unc option, as the
>     devname parameter is already converted!), and thus extract_hostname
>     is not able to function properly.
>
>     Question #2: Should this be considered a bug?
>
>     If that is the case, I would like to suggest the attached bugfix.
>
>     Please let me know what you think and thank you in advance for your
>     kind support!
>
>
>     Best regards,
>
>
>     --
>     Federico Sauter / Senior firmware programmer
>     Innominate Security Technologies AG / protecting industrial networks
>     tel: +49.30.921028-210 <tel:%2B49.30.921028-210> / fax:
>     +49.30.921028-020 <tel:%2B49.30.921028-020>
>     Rudower Chaussee 13 / D-12489 Berlin / http://www.innominate.com/
>
>     Register Court: AG Charlottenburg, HR B 81603
>     Management Board: Dirk Seewald
>     Chairman of the Supervisory Board: Christoph Leifer
>
>
>
>
> --
> Thanks,
>
> Steve

Re: Issue with upgrade to kernel 3.4.10 -> invalid argument error

[Federico Sauter]

[-- Attachment #1: Type: text/plain, Size: 1570 bytes --]

Dear Suresh,


I took a look at the patch that you mention, but *no*, it does not 
address the issue that I mention. The new code still does not convert 
all slashes to backslashes in the UNC field (i.e. the UNC given 
explicitly as in the unc= option.) Thus, it is still possible to get an 
"invalid parameter" error if you provide the UNC with slashes in it:

mount.cifs //myserver/share /mnt/point -o unc=//myserver/share

This will result in an error, since the unc option contains slashes and 
is converted as follows:

\\myserver/share

Thus causing an error within the extract_hostname function in connect.c.

Please take a look at the attached patch, which corrects this issue and 
let me know what you think. :-)


Thanks and regards

Fred


On 10/17/2012 11:55 AM, Suresh Jayaraman wrote:
> On 10/16/2012 10:33 PM, Federico Sauter wrote:
>> Greetings,
>>
>>
>> I am having an issue mounting CIFS shares since we upgraded our Linux
>> kernel from 2.6.27 to 3.4.10. Each time I try to mount a share drive I
>> get an "Invalid argument" error message even though I am using the same
>> command line that had previously worked, e.g.:
>>
>
> A quick look suggests that the symptom is similar to the one fixed by
> the below commit
>
> commit e73f843a3235a19de38359c91586e9eadef12238
> Author: Suresh Jayaraman<sjayaraman-IBi9RG/b67k@public.gmane.org>
> Date:   Tue Jun 12 07:15:50 2012 +0530
>
>      cifs: fix parsing of password mount option
>
>
> It might be worth trying to see whether the commit fixes the problem you
> are seeing.
>
>
> Thanks
> Suresh
>
>
>

[-- Attachment #2: connect.patch --]
[-- Type: text/x-patch, Size: 834 bytes --]

--- fs/cifs/connect.c.stable	2012-10-16 16:44:50.000000000 +0200
+++ fs/cifs/connect.c.fixed	2012-10-16 18:56:37.000000000 +0200
@@ -1204,6 +1204,7 @@
 	char *string = NULL;
 	char *tmp_end, *value;
 	char delim;
+	char *p, *q;
 
 	separator[0] = ',';
 	separator[1] = 0;
@@ -1662,12 +1663,12 @@
 				printk(KERN_WARNING "CIFS: no memory for UNC\n");
 				goto cifs_parse_mount_err;
 			}
-			strcpy(vol->UNC, string);
 
-			if (strncmp(string, "//", 2) == 0) {
-				vol->UNC[0] = '\\';
-				vol->UNC[1] = '\\';
-			} else if (strncmp(string, "\\\\", 2) != 0) {
+			for (p = string, q = vol->UNC; *p; ++p, ++q) {
+				*q = *p == '/'? '\\' : *p;
+			}
+			*q = '\0';
+			if (strncmp(vol->UNC, "\\\\", 2) != 0) {
 				printk(KERN_WARNING "CIFS: UNC Path does not "
 						    "begin with // or \\\\\n");
 				goto cifs_parse_mount_err;