• Eric Dumazet's avatar
    udp: fix behavior of wrong checksums · fcff4119
    Eric Dumazet authored
    [ Upstream commit beb39db5 ]
    
    We have two problems in UDP stack related to bogus checksums :
    
    1) We return -EAGAIN to application even if receive queue is not empty.
       This breaks applications using edge trigger epoll()
    
    2) Under UDP flood, we can loop forever without yielding to other
       processes, potentially hanging the host, especially on non SMP.
    
    This patch is an attempt to make things better.
    
    We might in the future add extra support for rt applications
    wanting to better control time spent doing a recv() in a hostile
    environment. For example we could validate checksums before queuing
    packets in socket receive queue.
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Cc: Willem de Bruijn <willemb@google.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
    fcff4119
udp.c 64.7 KB