diff --git a/drivers/infiniband/core/cma_configfs.c b/drivers/infiniband/core/cma_configfs.c
index 726e70b68249..4348adc570a0 100644
--- a/drivers/infiniband/core/cma_configfs.c
+++ b/drivers/infiniband/core/cma_configfs.c
@@ -218,7 +218,7 @@ static int make_cma_ports(struct cma_dev_group *cma_dev_group,
 	}
 
 	for (i = 0; i < ports_num; i++) {
-		char port_str[10];
+		char port_str[11];
 
 		ports[i].port_num = i + 1;
 		snprintf(port_str, sizeof(port_str), "%u", i + 1);