solos-pci: fix double-free of TX skb in DMA mode
David Woodhouse [Tue, 11 Dec 2012 14:57:14 +0000 (14:57 +0000)]
We weren't clearing card->tx_skb[port] when processing the TX done interrupt.
If there wasn't another skb ready to transmit immediately, this led to a
double-free because we'd free it *again* next time we did have a packet to
send.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/atm/solos-pci.c

index 6619a8a..c909b7b 100644 (file)
@@ -945,10 +945,11 @@ static uint32_t fpga_tx(struct solos_card *card)
        for (port = 0; tx_pending; tx_pending >>= 1, port++) {
                if (tx_pending & 1) {
                        struct sk_buff *oldskb = card->tx_skb[port];
-                       if (oldskb)
+                       if (oldskb) {
                                pci_unmap_single(card->dev, SKB_CB(oldskb)->dma_addr,
                                                 oldskb->len, PCI_DMA_TODEVICE);
-
+                               card->tx_skb[port] = NULL;
+                       }
                        spin_lock(&card->tx_queue_lock);
                        skb = skb_dequeue(&card->tx_queue[port]);
                        if (!skb)