diff --git a/drivers/s390/net/lcs.c b/drivers/s390/net/lcs.c
index a3adf4b1c60d..2ca0f1dd7a00 100644
--- a/drivers/s390/net/lcs.c
+++ b/drivers/s390/net/lcs.c
@@ -282,7 +282,7 @@ lcs_setup_write_ccws(struct lcs_card *card)
 
 	LCS_DBF_TEXT(3, setup, "iwritccw");
 	/* Setup write ccws. */
-	memset(card->write.ccws, 0, sizeof(struct ccw1) * LCS_NUM_BUFFS + 1);
+	memset(card->write.ccws, 0, sizeof(struct ccw1) * (LCS_NUM_BUFFS + 1));
 	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
 		card->write.ccws[cnt].cmd_code = LCS_CCW_WRITE;
 		card->write.ccws[cnt].count = 0;