diff --git a/drivers/net/ethernet/sun/sunhme.c b/drivers/net/ethernet/sun/sunhme.c
index 48f0a96c0e9e..666998082998 100644
--- a/drivers/net/ethernet/sun/sunhme.c
+++ b/drivers/net/ethernet/sun/sunhme.c
@@ -2551,6 +2551,9 @@ static int happy_meal_sbus_probe_one(struct platform_device *op, int is_qfe)
 		goto err_out_clear_quattro;
 	}
 
+	/* BIGMAC may have bogus sizes */
+	if ((op->resource[3].end - op->resource[3].start) >= BMAC_REG_SIZE)
+		op->resource[3].end = op->resource[3].start + BMAC_REG_SIZE - 1;
 	hp->bigmacregs = devm_platform_ioremap_resource(op, 3);
 	if (IS_ERR(hp->bigmacregs)) {
 		dev_err(&op->dev, "Cannot map BIGMAC registers.\n");