On Fri, 2017-03-24 at 15:34 -0700, Cong Wang wrote: > (Cc'ing Michael Kerrisk) > > On Wed, Mar 22, 2017 at 10:18 PM, Eric Dumazet <eric.duma...@gmail.com> wrote: > > On Thu, 2017-03-23 at 13:22 +1100, Daurnimator wrote: > >> On 9 March 2017 at 14:10, Daurnimator <q...@daurnimator.com> wrote: > >> > When debugging https://github.com/daurnimator/lua-http/issues/73 which > >> > uses https://github.com/wahern/dns we ran into an issue where modern > >> > linux kernels return EINVAL if you try and re-use a udp socket. > >> > The issue seems to occur if you go from a local destination ip to a > >> > non-local one. > >> > >> Did anyone get a chance to look into this issue? > > > > I believe man page is not complete. > > > > A disconnect is needed before another connect() > > Is it? Making connect() reentrant is reasonable for connection-less > protocol like UDP, but I don't dig POSIX for the details. If so we need > something like below... > > --- a/net/ipv4/datagram.c > +++ b/net/ipv4/datagram.c > @@ -40,7 +40,7 @@ int __ip4_datagram_connect(struct sock *sk, struct > sockaddr *uaddr, int addr_len > sk_dst_reset(sk); > > oif = sk->sk_bound_dev_if; > - saddr = inet->inet_saddr; > + saddr = inet->inet_saddr = 0; > if (ipv4_is_multicast(usin->sin_addr.s_addr)) { > if (!oif) > oif = inet->mc_index;
Wont this break bind() ?
