mwifiex: fix bugs in event handling code

This patch ensures uniformity in event skb sent by interface code
(USB/PCIe/SDIO) which automatically fixes following bugs.

1) For USB interface, same buffer is reused for receiving cmd and
events from firmware. While handling events, we perform
skb_pull(skb, 4) to remove event header. Corresponding skb_push()
call is missing while submitting the buffer.
2) For PCIe interface, event skb is passed with event header.
Recently added uAP events EVENT_UAP_STA_ASSOC, EVENT_UAP_STA_DEAUTH
will not work for PCIe, as they assume event skb points to event body.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Kiran Divekar <dkiran@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/mwifiex/sdio.c

@@ -978,10 +978,10 @@ static int mwifiex_decode_rx_packet(struct mwifiex_adapter *adapter,
 		dev_dbg(adapter->dev, "info: --- Rx: Event ---\n");
 		adapter->event_cause = *(u32 *) skb->data;
 
-		skb_pull(skb, MWIFIEX_EVENT_HEADER_LEN);
-
 		if ((skb->len > 0) && (skb->len  < MAX_EVENT_SIZE))
-			memcpy(adapter->event_body, skb->data, skb->len);
+			memcpy(adapter->event_body,
+			       skb->data + MWIFIEX_EVENT_HEADER_LEN,
+			       skb->len);
 
 		/* event cause has been saved to adapter->event_cause */
 		adapter->event_received = true;

drivers/net/wireless/mwifiex/sta_event.c

@@ -406,9 +406,9 @@ int mwifiex_process_sta_event(struct mwifiex_private *priv)
 		break;
 
 	case EVENT_UAP_STA_ASSOC:
-		skb_pull(adapter->event_skb, MWIFIEX_UAP_EVENT_EXTRA_HEADER);
 		memset(&sinfo, 0, sizeof(sinfo));
-		event = (struct mwifiex_assoc_event *)adapter->event_skb->data;
+		event = (struct mwifiex_assoc_event *)
+			(adapter->event_body + MWIFIEX_UAP_EVENT_EXTRA_HEADER);
 		if (le16_to_cpu(event->type) == TLV_TYPE_UAP_MGMT_FRAME) {
 			len = -1;
 
@@ -433,9 +433,8 @@ int mwifiex_process_sta_event(struct mwifiex_private *priv)
 				 GFP_KERNEL);
 		break;
 	case EVENT_UAP_STA_DEAUTH:
-		skb_pull(adapter->event_skb, MWIFIEX_UAP_EVENT_EXTRA_HEADER);
-		cfg80211_del_sta(priv->netdev, adapter->event_skb->data,
-				 GFP_KERNEL);
+		cfg80211_del_sta(priv->netdev, adapter->event_body +
+				 MWIFIEX_UAP_EVENT_EXTRA_HEADER, GFP_KERNEL);
 		break;
 	case EVENT_UAP_BSS_IDLE:
 		priv->media_connected = false;

drivers/net/wireless/mwifiex/usb.c

@@ -91,16 +91,16 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
 			}
 			skb_copy_from_linear_data(skb, &tmp, sizeof(u32));
 			adapter->event_cause = le32_to_cpu(tmp);
-			skb_pull(skb, sizeof(u32));
 			dev_dbg(dev, "event_cause %#x\n", adapter->event_cause);
 
 			if (skb->len > MAX_EVENT_SIZE) {
 				dev_err(dev, "EVENT: event body too large\n");
 				return -1;
 			}
 
-			skb_copy_from_linear_data(skb, adapter->event_body,
-						  skb->len);
+			memcpy(adapter->event_body, skb->data +
+			       MWIFIEX_EVENT_HEADER_LEN, skb->len);
+
 			adapter->event_received = true;
 			adapter->event_skb = skb;
 			break;