Commit a05948f2 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller

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: default avatarChristoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Tested-by: default avatarChristoph Paasch <christoph.paasch@uclouvain.be>
Cc: Sony Chacko <sony.chacko@qlogic.com>
Cc: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: default avatarChristoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d721a175
...@@ -144,7 +144,7 @@ void netxen_release_tx_buffers(struct netxen_adapter *adapter) ...@@ -144,7 +144,7 @@ void netxen_release_tx_buffers(struct netxen_adapter *adapter)
buffrag->length, PCI_DMA_TODEVICE); buffrag->length, PCI_DMA_TODEVICE);
buffrag->dma = 0ULL; buffrag->dma = 0ULL;
} }
for (j = 0; j < cmd_buf->frag_count; j++) { for (j = 1; j < cmd_buf->frag_count; j++) {
buffrag++; buffrag++;
if (buffrag->dma) { if (buffrag->dma) {
pci_unmap_page(adapter->pdev, buffrag->dma, pci_unmap_page(adapter->pdev, buffrag->dma,
......
...@@ -1963,10 +1963,12 @@ netxen_map_tx_skb(struct pci_dev *pdev, ...@@ -1963,10 +1963,12 @@ netxen_map_tx_skb(struct pci_dev *pdev,
while (--i >= 0) { while (--i >= 0) {
nf = &pbuf->frag_array[i+1]; nf = &pbuf->frag_array[i+1];
pci_unmap_page(pdev, nf->dma, nf->length, PCI_DMA_TODEVICE); pci_unmap_page(pdev, nf->dma, nf->length, PCI_DMA_TODEVICE);
nf->dma = 0ULL;
} }
nf = &pbuf->frag_array[0]; nf = &pbuf->frag_array[0];
pci_unmap_single(pdev, nf->dma, skb_headlen(skb), PCI_DMA_TODEVICE); pci_unmap_single(pdev, nf->dma, skb_headlen(skb), PCI_DMA_TODEVICE);
nf->dma = 0ULL;
out_err: out_err:
return -ENOMEM; return -ENOMEM;
......
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