net: dsa: Error out on tagging protocol mismatches

If there is a mismatch between enabled tagging protocols and the
protocol the switch supports, error out, rather than continue with a
situation which is unlikely to work.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
cc: alexander.h.duyck@intel.com
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 1 deletions

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 22f34cf4cb27..6317b41c99b0 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -174,8 +174,11 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
                         dst->rcv = brcm_netdev_ops.rcv;
                         break;
 #endif
-                default:
+                case DSA_TAG_PROTO_NONE:
                         break;
+                default:
+                        ret = -ENOPROTOOPT;
+                        goto out;
                 }
 
                 dst->tag_protocol = drv->tag_protocol;