From 5086df9f1f3925734229495b3e467c0ba6c07346 Mon Sep 17 00:00:00 2001
From: Adrian Chadd <adrian@FreeBSD.org>
Date: Mon, 13 May 2013 21:17:27 +0000
Subject: [PATCH] Support sending ATH_ALQ messages with no payload.

---
 sys/dev/ath/if_ath_alq.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/sys/dev/ath/if_ath_alq.c b/sys/dev/ath/if_ath_alq.c
index 1ad13db5e75d..8ca53ae2c579 100644
--- a/sys/dev/ath/if_ath_alq.c
+++ b/sys/dev/ath/if_ath_alq.c
@@ -184,9 +184,11 @@ if_ath_alq_post(struct if_ath_alq *alq, uint16_t op, uint16_t len,
 	/*
 	 * Copy the payload _after_ the header field.
 	 */
-	memcpy(((char *) ap) + sizeof(struct if_ath_alq_hdr),
-	    buf,
-	    len);
+	if (buf != NULL) {
+		memcpy(((char *) ap) + sizeof(struct if_ath_alq_hdr),
+		    buf,
+		    len);
+	}
 
 	alq_post(alq->sc_alq_alq, ale);
 }