NFSv4: Disallow 'mount -t nfs4 -overs=2' and 'mount -t nfs4 -overs=3'

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 34b1ccf..867f705 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2321,6 +2321,12 @@ static int nfs4_validate_text_mount_data(void *options,
 
        nfs4_validate_mount_flags(args);
 
+       if (args->version != 4) {
+               dfprintk(MOUNT,
+                        "NFS4: Illegal mount version\n");
+               return -EINVAL;
+       }
+
        if (args->auth_flavor_len > 1) {
                dfprintk(MOUNT,
                         "NFS4: Too many RPC auth flavours specified\n");