2013-12-16 03:19:08

by Tony Asleson

Subject: exportfs: Messages indicating unsupported operation that works

When I try to export a directory that has a space in it I get the following:

# exportfs *:"/mnt/has space"
exportfs: /mnt/has space does not support NFS export

exit code is 0.

If I do:

# exportfs -v
/mnt/has space <world>(ro,wdelay,root_squash,no_subtree_check,
sec=sys,ro,secure,root_squash,no_all_squash)

It exists and I can mount it from a client and everything appears fine.

I took a peek at the code and we are failing in test_export. We are
getting a -1 returned when we write to: /proc/net/rpc/nfsd.export/channel .

This seems like a confusing message when it appears that everything is
working, thoughts?

Notes:
- Kernel Linux rawhide 3.13.0-0.rc3.git1.2.fc21.x86_64
- nfs-utils: Latest from git, but this happens on older released
versions tested too.

Thanks,
Tony

2013-12-16 18:36:11

by J. Bruce Fields

Subject: Re: exportfs: Messages indicating unsupported operation that works

On Sun, Dec 15, 2013 at 09:19:07PM -0600, Tony Asleson wrote:
> When I try to export a directory that has a space in it I get the following:
>
> # exportfs *:"/mnt/has space"
> exportfs: /mnt/has space does not support NFS export
>
> exit code is 0.
>
> If I do:
>
> # exportfs -v
> /mnt/has space <world>(ro,wdelay,root_squash,no_subtree_check,
> sec=sys,ro,secure,root_squash,no_all_squash)
>
> It exists and I can mount it from a client and everything appears fine.
>
> I took a peek at the code and we are failing in test_export. We are
> getting a -1 returned when we write to: /proc/net/rpc/nfsd.export/channel .
>
> This seems like a confusing message when it appears that everything is
> working, thoughts?
>
> Notes:
> - Kernel Linux rawhide 3.13.0-0.rc3.git1.2.fc21.x86_64
> - nfs-utils: Latest from git, but this happens on older released
> versions tested too.

test_export clearly isn't escaping the pathname. It probably needs
something like the following (completely untested).

--b.

diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c
index 4331697..d5dfb0b 100644
--- a/utils/exportfs/exportfs.c
+++ b/utils/exportfs/exportfs.c
@@ -418,11 +418,15 @@ static int can_test(void)
static int test_export(char *path, int with_fsid)
{
char buf[1024];
+ char *bp = buf;
+ int len = sizeof(buf);
int fd, n;

- sprintf(buf, "-test-client- %s 3 %d 65534 65534 0\n",
- path,
- with_fsid ? NFSEXP_FSID : 0);
+ n = sprintf(buf, "-test-client- ");
+ bp += n;
+ len -= n;
+ qword_add(&bp, &len, path);
+ sprintf(bp, " 3 %d 65534 65534 0\n", with_fsid ? NFSEXP_FSID : 0);
fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
if (fd < 0)
return 0;