[PATCH 3.16 078/129] fs/nfs: Fix nfs_parse_devname to not modify it's argument

[Ben Hutchings]

3.16.70-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>

commit 40cc394be1aa18848b8757e03bd8ed23281f572e upstream.

In the rare and unsupported case of a hostname list nfs_parse_devname
will modify dev_name.  There is no need to modify dev_name as the all
that is being computed is the length of the hostname, so the computed
length can just be shorted.

Fixes: dc04589827f7 ("NFS: Use common device name parsing logic for NFSv4 and NFSv2/v3")
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 fs/nfs/super.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1893,7 +1893,7 @@ static int nfs_parse_devname(const char
 		/* kill possible hostname list: not supported */
 		comma = strchr(dev_name, ',');
 		if (comma != NULL && comma < end)
-			*comma = 0;
+			len = comma - dev_name;
 	}
 
 	if (len > maxnamlen)