diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c
index cdd4c09fda96..a22a7a502740 100644
--- a/drivers/char/ipmi/ipmi_bt_sm.c
+++ b/drivers/char/ipmi/ipmi_bt_sm.c
@@ -95,9 +95,9 @@ struct si_sm_data {
 	enum bt_states	state;
 	unsigned char	seq;		/* BT sequence number */
 	struct si_sm_io	*io;
-	unsigned char	write_data[IPMI_MAX_MSG_LENGTH];
+	unsigned char	write_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */
 	int		write_count;
-	unsigned char	read_data[IPMI_MAX_MSG_LENGTH];
+	unsigned char	read_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */
 	int		read_count;
 	int		truncated;
 	long		timeout;	/* microseconds countdown */