Digi del-5.6 Complete2.6.31-digi-201102151558

1 files changed, 28 insertions, 8 deletions

diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c
index 7964cc32b258..32e9513bbc0b 100644
--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -1158,8 +1158,9 @@ struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
 }
 
 static int dma_tx_fragment(struct b43_dmaring *ring,
-			   struct sk_buff *skb)
+			   struct sk_buff **in_skb)
 {
+	struct sk_buff *skb = *in_skb;
 	const struct b43_dma_ops *ops = ring->ops;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	u8 *header;
@@ -1225,8 +1226,14 @@ static int dma_tx_fragment(struct b43_dmaring *ring,
 		}
 
 		memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
+		memcpy(bounce_skb->cb, skb->cb, sizeof(skb->cb));
+		bounce_skb->dev = skb->dev;
+		skb_set_queue_mapping(bounce_skb, skb_get_queue_mapping(skb));
+		info = IEEE80211_SKB_CB(bounce_skb);
+
 		dev_kfree_skb_any(skb);
 		skb = bounce_skb;
+		*in_skb = bounce_skb;
 		meta->skb = skb;
 		meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
 		if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
@@ -1334,13 +1341,22 @@ int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
 	spin_lock_irqsave(&ring->lock, flags);
 
 	B43_WARN_ON(!ring->tx);
-	/* Check if the queue was stopped in mac80211,
-	 * but we got called nevertheless.
-	 * That would be a mac80211 bug. */
-	B43_WARN_ON(ring->stopped);
 
-	if (unlikely(free_slots(ring) < TX_SLOTS_PER_FRAME)) {
-		b43warn(dev->wl, "DMA queue overflow\n");
+	if (unlikely(ring->stopped)) {
+		/* We get here only because of a bug in mac80211.
+		 * Because of a race, one packet may be queued after
+		 * the queue is stopped, thus we got called when we shouldn't.
+		 * For now, just refuse the transmit. */
+		if (b43_debug(dev, B43_DBG_DMAVERBOSE))
+			b43err(dev->wl, "Packet after queue stopped\n");
+		err = -ENOSPC;
+		goto out_unlock;
+	}
+
+	if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
+		/* If we get here, we have a real error with the queue
+		 * full, but queues not stopped. */
+		b43err(dev->wl, "DMA queue overflow\n");
 		err = -ENOSPC;
 		goto out_unlock;
 	}
@@ -1350,7 +1366,11 @@ int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
 	 * static, so we don't need to store it per frame. */
 	ring->queue_prio = skb_get_queue_mapping(skb);
 
-	err = dma_tx_fragment(ring, skb);
+	/* dma_tx_fragment might reallocate the skb, so invalidate pointers pointing
+	 * into the skb data or cb now. */
+	hdr = NULL;
+	info = NULL;
+	err = dma_tx_fragment(ring, &skb);
 	if (unlikely(err == -ENOKEY)) {
 		/* Drop this packet, as we don't have the encryption key
 		 * anymore and must not transmit it unencrypted. */