netxen: fix off by one bug in netxen_release_tx_buffer()

Christoph Paasch found netxen could trigger a BUG in its dismantle
phase, in netxen_release_tx_buffer(), using full size TSO packets.

cmd_buf->frag_count includes the skb->data part, so the loop must
start at index 1 instead of 0, or else we can make an out
of bound access to cmd_buff->frag_array[MAX_SKB_FRAGS + 2]

Christoph provided the fixes in netxen_map_tx_skb() function.
In case of a dma mapping error, its better to clear the dma fields
so that we don't try to unmap them again in netxen_release_tx_buffer()

Reported-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Cc: Sony Chacko <sony.chacko@qlogic.com>
Cc: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
index bc165f4d0f65cebb6cc82e3aa99590863963f767..695667d471a1bef8dc81dd8034a593a118993e07 100644 (file)
--- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
+++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
@@ -144,7 +144,7 @@ void netxen_release_tx_buffers(struct netxen_adapter *adapter)
                                         buffrag->length, PCI_DMA_TODEVICE);
                        buffrag->dma = 0ULL;
                }
-               for (j = 0; j < cmd_buf->frag_count; j++) {
+               for (j = 1; j < cmd_buf->frag_count; j++) {
                        buffrag++;
                        if (buffrag->dma) {
                                pci_unmap_page(adapter->pdev, buffrag->dma,

diff --git a/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c b/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
index 6098fd4adfeb89ef5ed9c15407799ddbdcf02e7a..69e321a650779c9d3bae975a273035b922fca08f 100644 (file)
--- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
+++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
@@ -1963,10 +1963,12 @@ unwind:
        while (--i >= 0) {
                nf = &pbuf->frag_array[i+1];
                pci_unmap_page(pdev, nf->dma, nf->length, PCI_DMA_TODEVICE);
+               nf->dma = 0ULL;
        }
 
        nf = &pbuf->frag_array[0];
        pci_unmap_single(pdev, nf->dma, skb_headlen(skb), PCI_DMA_TODEVICE);
+       nf->dma = 0ULL;
 
 out_err:
        return -ENOMEM;