diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index af51cf9..8513c59 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -580,16 +580,25 @@
 		if (err)
 			goto out4;
 		/*
+		 * No point caching this if it would immediately expire.
+		 * Also, this protects exportfs's dummy export from the
+		 * anon_uid/anon_gid checks:
+		 */
+		if (exp.h.expiry_time < seconds_since_boot())
+			goto out4;
+		/*
 		 * For some reason exportfs has been passing down an
 		 * invalid (-1) uid & gid on the "dummy" export which it
 		 * uses to test export support.  To make sure exportfs
 		 * sees errors from check_export we therefore need to
 		 * delay these checks till after check_export:
 		 */
+		err = -EINVAL;
 		if (!uid_valid(exp.ex_anon_uid))
 			goto out4;
 		if (!gid_valid(exp.ex_anon_gid))
 			goto out4;
+		err = 0;
 	}
 
 	expp = svc_export_lookup(&exp);