NFSv4: Refuse mount attempts with proto=udp

RFC3530 disallows the use of udp as a transport protocol for NFSv4.

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

1 files changed, 12 insertions, 0 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 71fdc0dfa0d2..f2071d221c77 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2084,6 +2084,8 @@ static int nfs_validate_text_mount_data(void *options,
                 max_namelen = NFS4_MAXNAMLEN;
                 max_pathlen = NFS4_MAXPATHLEN;
                 nfs_validate_transport_protocol(args);
+                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
+                        goto out_invalid_transport_udp;
                 nfs4_validate_mount_flags(args);
 #else
                 goto out_v4_not_compiled;
@@ -2106,6 +2108,10 @@ static int nfs_validate_text_mount_data(void *options,
 out_v4_not_compiled:
         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
         return -EPROTONOSUPPORT;
+#else
+out_invalid_transport_udp:
+        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
+        return -EINVAL;
 #endif /* !CONFIG_NFS_V4 */
 
 out_no_address:
@@ -2711,6 +2717,8 @@ static int nfs4_validate_mount_data(void *options,
                 args->acdirmax  = data->acdirmax;
                 args->nfs_server.protocol = data->proto;
                 nfs_validate_transport_protocol(args);
+                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
+                        goto out_invalid_transport_udp;
 
                 break;
         default:
@@ -2731,6 +2739,10 @@ out_inval_auth:
 out_no_address:
         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
         return -EINVAL;
+
+out_invalid_transport_udp:
+        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
+        return -EINVAL;
 }
 
 /*