• Xuan Zhuo's avatar
    virtio-net: fix for skb_over_panic inside big mode · 1a802423
    Xuan Zhuo authored
    In virtio-net's large packet mode, there is a hole in the space behind
    buf.
    
        hdr_padded_len - hdr_len
    
    We must take this into account when calculating tailroom.
    
    [   44.544385] skb_put.cold (net/core/skbuff.c:5254 (discriminator 1) net/core/skbuff.c:5252 (discriminator 1))
    [   44.544864] page_to_skb (drivers/net/virtio_net.c:485) [   44.545361] receive_buf (drivers/net/virtio_net.c:849 drivers/net/virtio_net.c:1131)
    [   44.545870] ? netif_receive_skb_list_internal (net/core/dev.c:5714)
    [   44.546628] ? dev_gro_receive (net/core/dev.c:6103)
    [   44.547135] ? napi_complete_done (./include/linux/list.h:35 net/core/dev.c:5867 net/core/dev.c:5862 net/core/dev.c:6565)
    [   44.547672] virtnet_poll (drivers/net/virtio_net.c:1427 drivers/net/virtio_net.c:1525)
    [   44.548251] __napi_poll (net/core/dev.c:6985)
    [   44.548744] net_rx_action (net/core/dev.c:7054 net/core/dev.c:7139)
    [   44.549264] __do_softirq (./arch/x86/include/asm/jump_label.h:19 ./include/linux/jump_label.h:200 ./include/trace/events/irq.h:142 kernel/softirq.c:560)
    [   44.549762] irq_exit_rcu (kernel/softirq.c:433 kernel/softirq.c:637 kernel/softirq.c:649)
    [   44.551384] common_interrupt (arch/x86/kernel/irq.c:240 (discriminator 13))
    [   44.551991] ? asm_common_interrupt (./arch/x86/include/asm/idtentry.h:638)
    [   44.552654] asm_common_interrupt (./arch/x86/include/asm/idtentry.h:638)
    
    Fixes: fb32856b ("virtio-net: page_to_skb() use build_skb when there's sufficient tailroom")
    Signed-off-by: default avatarXuan Zhuo <xuanzhuo@linux.alibaba.com>
    Reported-by: default avatarCorentin Noël <corentin.noel@collabora.com>
    Tested-by: default avatarCorentin Noël <corentin.noel@collabora.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    1a802423
virtio_net.c 87 KB