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 <lasz...@gmail.com>
---
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(&opt->inet.sk);
                        rcu_read_lock();
                        dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
-                       if (!dev ||
-                           !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) {
+                       if (!dev || !(opt->inet.freebind ||
+                                     net->ipv6.sysctl.ip_nonlocal_bind ||
+                                     ipv6_chk_addr(net, &addr->v6.sin6_addr,
+                                                   dev, 0))) {
                                rcu_read_unlock();
                                return 0;
                        }
-- 
2.7.4

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