net: wireless: wcn36xx: fix potential NULL pointer dereference

If kmalloc fails wcn36xx_smd_rsp_process will attempt to dereference
a NULL pointer.  There might be a better error recovery then just
printing an error, but printing an error message is better then the
current behaviour.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/wcn36xx/smd.c

@@ -2041,13 +2041,20 @@ static void wcn36xx_smd_rsp_process(struct wcn36xx *wcn, void *buf, size_t len)
 	case WCN36XX_HAL_DELETE_STA_CONTEXT_IND:
 		mutex_lock(&wcn->hal_ind_mutex);
 		msg_ind = kmalloc(sizeof(*msg_ind), GFP_KERNEL);
+		if (msg_ind) {
 			msg_ind->msg_len = len;
 			msg_ind->msg = kmalloc(len, GFP_KERNEL);
 			memcpy(msg_ind->msg, buf, len);
 			list_add_tail(&msg_ind->list, &wcn->hal_ind_queue);
 			queue_work(wcn->hal_ind_wq, &wcn->hal_ind_work);
 			wcn36xx_dbg(WCN36XX_DBG_HAL, "indication arrived\n");
+		}
 		mutex_unlock(&wcn->hal_ind_mutex);
+		if (msg_ind)
+			break;
+		/* FIXME: Do something smarter then just printing an error. */
+		wcn36xx_err("Run out of memory while handling SMD_EVENT (%d)\n",
+			    msg_header->msg_type);
 		break;
 	default:
 		wcn36xx_err("SMD_EVENT (%d) not supported\n",