From: Eric Dumazet Date: Sat, 18 Sep 2010 05:58:08 +0000 (-0700) Subject: qlcnic: dont assume NET_IP_ALIGN is 2 X-Git-Tag: v2.6.36-rc6~6^2~45 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=04746ff1289f75af26af279eb4b0b3e231677ee4;p=~shefty%2Frdma-dev.git qlcnic: dont assume NET_IP_ALIGN is 2 qlcnic driver allocates rx skbs and gives to hardware too bytes of extra storage, allowing for corruption of kernel data. NET_IP_ALIGN being 0 on some platforms (including x86), drivers should not assume it's 2. rds_ring->skb_size = rds_ring->dma_size + NET_IP_ALIGN; ... skb = dev_alloc_skb(rds_ring->skb_size); skb_reserve(skb, 2); pci_map_single(pdev, skb->data, rds_ring->dma_size, PCI_DMA_FROMDEVICE); (and rds_ring->skb_size == rds_ring->dma_size) -> bug Because of extra alignment (1500 + 32) -> four extra bytes are available before the struct skb_shared_info, so corruption is not noticed. Note: this driver could use netdev_alloc_skb_ip_align() Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- diff --git a/drivers/net/qlcnic/qlcnic_init.c b/drivers/net/qlcnic/qlcnic_init.c index 75ba744b173..60ab753f809 100644 --- a/drivers/net/qlcnic/qlcnic_init.c +++ b/drivers/net/qlcnic/qlcnic_init.c @@ -1316,7 +1316,7 @@ qlcnic_alloc_rx_skb(struct qlcnic_adapter *adapter, return -ENOMEM; } - skb_reserve(skb, 2); + skb_reserve(skb, NET_IP_ALIGN); dma = pci_map_single(pdev, skb->data, rds_ring->dma_size, PCI_DMA_FROMDEVICE);