Index: head/sys/net/if_mib.c
===================================================================
--- head/sys/net/if_mib.c
+++ head/sys/net/if_mib.c
@@ -122,10 +122,6 @@
 		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
 		if (error || !req->newptr)
 			goto out;
-
-		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
-		if (error)
-			goto out;
 		break;
 
 	case IFDATA_DRIVERNAME:
@@ -152,6 +148,6 @@
 }
 
 static SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata,
-    CTLFLAG_RW | CTLFLAG_NEEDGIANT, sysctl_ifdata,
+    CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ifdata,
     "Interface table");