[03/12] mwl8k: prevent corruption of QoS field on receive

Commit Message

Lennert Buytenhek Nov. 30, 2009, 5:12 p.m. UTC

None

Patch

diff --git a/drivers/net/wireless/mwl8k.c b/drivers/net/wireless/mwl8k.c
index a72ee1f..8eed851 100644
--- a/drivers/net/wireless/mwl8k.c
+++ b/drivers/net/wireless/mwl8k.c
@@ -84,7 +84,8 @@  struct rxd_ops {
 	int rxd_size;
 	void (*rxd_init)(void *rxd, dma_addr_t next_dma_addr);
 	void (*rxd_refill)(void *rxd, dma_addr_t addr, int len);
-	int (*rxd_process)(void *rxd, struct ieee80211_rx_status *status);
+	int (*rxd_process)(void *rxd, struct ieee80211_rx_status *status,
+			   __le16 *qos);
 };
 
 struct mwl8k_device_info {
@@ -699,21 +700,29 @@  static inline u16 mwl8k_qos_setbit_qlen(u16 qos, u8 len)
 struct mwl8k_dma_data {
 	__le16 fwlen;
 	struct ieee80211_hdr wh;
+	char data[0];
 } __attribute__((packed));
 
 /* Routines to add/remove DMA header from skb.  */
-static inline void mwl8k_remove_dma_header(struct sk_buff *skb)
+static inline void mwl8k_remove_dma_header(struct sk_buff *skb, __le16 qos)
 {
-	struct mwl8k_dma_data *tr = (struct mwl8k_dma_data *)skb->data;
-	void *dst, *src = &tr->wh;
-	int hdrlen = ieee80211_hdrlen(tr->wh.frame_control);
-	u16 space = sizeof(struct mwl8k_dma_data) - hdrlen;
+	struct mwl8k_dma_data *tr;
+	int hdrlen;
+
+	tr = (struct mwl8k_dma_data *)skb->data;
+	hdrlen = ieee80211_hdrlen(tr->wh.frame_control);
 
-	dst = (void *)tr + space;
-	if (dst != src) {
-		memmove(dst, src, hdrlen);
-		skb_pull(skb, space);
+	if (hdrlen != sizeof(tr->wh)) {
+		if (ieee80211_is_data_qos(tr->wh.frame_control)) {
+			memmove(tr->data - hdrlen, &tr->wh, hdrlen - 2);
+			*((__le16 *)(tr->data - 2)) = qos;
+		} else {
+			memmove(tr->data - hdrlen, &tr->wh, hdrlen);
+		}
 	}
+
+	if (hdrlen != sizeof(*tr))
+		skb_pull(skb, sizeof(*tr) - hdrlen);
 }
 
 static inline void mwl8k_add_dma_header(struct sk_buff *skb)
@@ -793,7 +802,8 @@  static void mwl8k_rxd_8366_refill(void *_rxd, dma_addr_t addr, int len)
 }
 
 static int
-mwl8k_rxd_8366_process(void *_rxd, struct ieee80211_rx_status *status)
+mwl8k_rxd_8366_process(void *_rxd, struct ieee80211_rx_status *status,
+		       __le16 *qos)
 {
 	struct mwl8k_rxd_8366 *rxd = _rxd;
 
@@ -823,6 +833,8 @@  mwl8k_rxd_8366_process(void *_rxd, struct ieee80211_rx_status *status)
 	status->band = IEEE80211_BAND_2GHZ;
 	status->freq = ieee80211_channel_to_frequency(rxd->channel);
 
+	*qos = rxd->qos_control;
+
 	return le16_to_cpu(rxd->pkt_len);
 }
 
@@ -881,7 +893,8 @@  static void mwl8k_rxd_8687_refill(void *_rxd, dma_addr_t addr, int len)
 }
 
 static int
-mwl8k_rxd_8687_process(void *_rxd, struct ieee80211_rx_status *status)
+mwl8k_rxd_8687_process(void *_rxd, struct ieee80211_rx_status *status,
+		       __le16 *qos)
 {
 	struct mwl8k_rxd_8687 *rxd = _rxd;
 	u16 rate_info;
@@ -912,6 +925,8 @@  mwl8k_rxd_8687_process(void *_rxd, struct ieee80211_rx_status *status)
 	status->band = IEEE80211_BAND_2GHZ;
 	status->freq = ieee80211_channel_to_frequency(rxd->channel);
 
+	*qos = rxd->qos_control;
+
 	return le16_to_cpu(rxd->pkt_len);
 }
 
@@ -1083,6 +1098,7 @@  static int rxq_process(struct ieee80211_hw *hw, int index, int limit)
 		void *rxd;
 		int pkt_len;
 		struct ieee80211_rx_status status;
+		__le16 qos;
 
 		skb = rxq->buf[rxq->head].skb;
 		if (skb == NULL)
@@ -1090,7 +1106,7 @@  static int rxq_process(struct ieee80211_hw *hw, int index, int limit)
 
 		rxd = rxq->rxd + (rxq->head * priv->rxd_ops->rxd_size);
 
-		pkt_len = priv->rxd_ops->rxd_process(rxd, &status);
+		pkt_len = priv->rxd_ops->rxd_process(rxd, &status, &qos);
 		if (pkt_len < 0)
 			break;
 
@@ -1108,7 +1124,7 @@  static int rxq_process(struct ieee80211_hw *hw, int index, int limit)
 		rxq->rxd_count--;
 
 		skb_put(skb, pkt_len);
-		mwl8k_remove_dma_header(skb);
+		mwl8k_remove_dma_header(skb, qos);
 
 		/*
 		 * Check for a pending join operation.  Save a
@@ -1354,7 +1370,7 @@  static void mwl8k_txq_reclaim(struct ieee80211_hw *hw, int index, int force)
 		BUG_ON(skb == NULL);
 		pci_unmap_single(priv->pdev, addr, size, PCI_DMA_TODEVICE);
 
-		mwl8k_remove_dma_header(skb);
+		mwl8k_remove_dma_header(skb, tx_desc->qos_control);
 
 		/* Mark descriptor as unused */
 		tx_desc->pkt_phys_addr = 0;