From d2d8cda7fc0b7a133492e70332217a7f20757615 Mon Sep 17 00:00:00 2001 From: Larry Finger Date: Fri, 30 Oct 2009 11:58:21 -0500 Subject: [PATCH] b43legacy: Fix DMA TX bounce buffer copying This patch is adapted from the submission by Michael Buesch for a bounce-buffer copying problem with b43. Signed-off-by: Larry Finger Signed-off-by: John W. Linville --- drivers/net/wireless/b43legacy/dma.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/b43legacy/dma.c b/drivers/net/wireless/b43legacy/dma.c index 866403415811..0a86bdf53154 100644 --- a/drivers/net/wireless/b43legacy/dma.c +++ b/drivers/net/wireless/b43legacy/dma.c @@ -1240,8 +1240,9 @@ struct b43legacy_dmaring *parse_cookie(struct b43legacy_wldev *dev, } static int dma_tx_fragment(struct b43legacy_dmaring *ring, - struct sk_buff *skb) + struct sk_buff **in_skb) { + struct sk_buff *skb = *in_skb; const struct b43legacy_dma_ops *ops = ring->ops; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); u8 *header; @@ -1305,8 +1306,14 @@ static int dma_tx_fragment(struct b43legacy_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 (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) { @@ -1360,8 +1367,10 @@ int b43legacy_dma_tx(struct b43legacy_wldev *dev, struct sk_buff *skb) { struct b43legacy_dmaring *ring; + struct ieee80211_hdr *hdr; int err = 0; unsigned long flags; + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); ring = priority_to_txring(dev, skb_get_queue_mapping(skb)); spin_lock_irqsave(&ring->lock, flags); @@ -1386,7 +1395,11 @@ int b43legacy_dma_tx(struct b43legacy_wldev *dev, goto out_unlock; } - 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. */ -- 2.30.2