Re: [PATCH 06/17] SUNRPC: Set IPV6ONLY flag on PF_INET6 RPC listenersockets

[Trond Myklebust <Trond.Myklebust@netapp.com>]

On Tue, 2009-03-03 at 15:32 -0700, Chuck Lever wrote:
> We are about to convert to using separate RPC listener sockets for
> AF_INET and AF_INET6.  This echoes the way IPv6 is handled in user
> space by TI-RPC, and eliminates the need to worry about mapped IPv4
> AF_INET6 addresses when doing address comparisons.
> 
> Start by setting the IPV6ONLY flag on RPC listener sockets.
> 
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
> 
>  net/sunrpc/svcsock.c |   10 ++++------
>  1 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
> index d00bc33..ac6cd65 100644
> --- a/net/sunrpc/svcsock.c
> +++ b/net/sunrpc/svcsock.c
> @@ -1144,13 +1144,11 @@ static struct svc_sock
> *svc_setup_socket(struct svc_serv *serv,
>                 svc_tcp_init(svsk, serv);
> 
>         /*
> -        * We start one listener per sv_serv.  We want AF_INET
> -        * requests to be automatically shunted to our PF_INET6
> -        * listener using a mapped IPv4 address.  Make sure
> -        * no-one starts an equivalent IPv4 listener, which
> -        * would steal our incoming connections.
> +        * If this is a PF_INET6 listener, we want to avoid
> +        * getting requests from IPv4 remotes.  Those should
> +        * be shunted to a PF_INET listener via rpcbind.
>          */
> -       val = 0;
> +       val = 1;
>         if (inet->sk_family == PF_INET6)
			         AF_INET6...

...and this should probably be set before we bind the socket...

>                 kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
>                                         (char *)&val, sizeof(val));
> 
> 
> 
-- 
Trond Myklebust
Linux NFS client maintainer

NetApp
Trond.Myklebust@netapp.com
www.netapp.com