Re: [PATCH v2] sctp: full support for ipv6 ip_nonlocal_bind & IP_FREEBIND

[David Miller]

From: Laszlo Toth 
Date: Mon, 23 Oct 2017 19:19:33 +0200

> Commit 9b9742022888 ("sctp: support ipv6 nonlocal bind")
> introduced support for the above options as v4 sctp did,
> so patched sctp_v6_available().
> 
> In the v4 implementation it's enough, because
> sctp_inet_bind_verify() just returns with sctp_v4_available().
> However sctp_inet6_bind_verify() has an extra check before that
> for link-local scope_id, which won't respect the above options.
> 
> Added the checks before calling ipv6_chk_addr(), but
> not before the validation of scope_id.
> 
> before (w/ both options):
>  ./v6test fe80::10 sctp
>  bind failed, errno: 99 (Cannot assign requested address)
>  ./v6test fe80::10 tcp
>  bind success, errno: 0 (Success)
> 
> after (w/ both options):
>  ./v6test fe80::10 sctp
>  bind success, errno: 0 (Success)
> 
> Signed-off-by: Laszlo Toth 

Applied.

Re: [PATCH v2] sctp: full support for ipv6 ip_nonlocal_bind & IP_FREEBIND

[Xin Long]

On Tue, Oct 24, 2017 at 1:19 AM, Laszlo Toth  wrote:
> Commit 9b9742022888 ("sctp: support ipv6 nonlocal bind")
> introduced support for the above options as v4 sctp did,
> so patched sctp_v6_available().
>
> In the v4 implementation it's enough, because
> sctp_inet_bind_verify() just returns with sctp_v4_available().
> However sctp_inet6_bind_verify() has an extra check before that
> for link-local scope_id, which won't respect the above options.
>
> Added the checks before calling ipv6_chk_addr(), but
> not before the validation of scope_id.
>
> before (w/ both options):
>  ./v6test fe80::10 sctp
>  bind failed, errno: 99 (Cannot assign requested address)
>  ./v6test fe80::10 tcp
>  bind success, errno: 0 (Success)
>
> after (w/ both options):
>  ./v6test fe80::10 sctp
>  bind success, errno: 0 (Success)
>
> Signed-off-by: Laszlo Toth 
> ---
> changed in v2:
>  - fixed indentation
>
>  net/sctp/ipv6.c | 6 --
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
> index 51c4887..7fe9e1d1 100644
> --- a/net/sctp/ipv6.c
> +++ b/net/sctp/ipv6.c
> @@ -882,8 +882,10 @@ static int sctp_inet6_bind_verify(struct sctp_sock *opt, 
> union sctp_addr *addr)
> net = sock_net(>inet.sk);
> rcu_read_lock();
> dev = dev_get_by_index_rcu(net, 
> addr->v6.sin6_scope_id);
> -   if (!dev ||
> -   !ipv6_chk_addr(net, >v6.sin6_addr, dev, 0)) 
> {
> +   if (!dev || !(opt->inet.freebind ||
> + net->ipv6.sysctl.ip_nonlocal_bind ||
> + ipv6_chk_addr(net, >v6.sin6_addr,
> +   dev, 0))) {
> rcu_read_unlock();
> return 0;
> }
> --
> 2.7.4
>
Reviewed-by: Xin Long 

Thanks.