diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 55144f7d930373a8efdbdd48aba9c1121aa28bab..5e166282973278b88c662875a54c5ce87990605e 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3605,6 +3605,8 @@ static int setup_geo(struct geom *geo, struct mddev *mddev, enum geo_type new)
 	nc = layout & 255;
 	fc = (layout >> 8) & 255;
 	fo = layout & (1<<16);
+	if (!nc || !fc)
+		return -1;
 	geo->raid_disks = disks;
 	geo->near_copies = nc;
 	geo->far_copies = fc;