• Michael S. Tsirkin's avatar
    net: copy userspace buffers on device forwarding · 48c83012
    Michael S. Tsirkin authored
    
    
    dev_forward_skb loops an skb back into host networking
    stack which might hang on the memory indefinitely.
    In particular, this can happen in macvtap in bridged mode.
    Copy the userspace fragments to avoid blocking the
    sender in that case.
    
    As this patch makes skb_copy_ubufs extern now,
    I also added some documentation and made it clear
    the SKBTX_DEV_ZEROCOPY flag automatically instead
    of doing it in all callers. This can be made into a separate
    patch if people feel it's worth it.
    Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    48c83012