[PATCH v4 net] ipvs: fix bind to link-local mcast IPv6 address in backup
From: Quentin Armitage <hidden>
Date: 2016-06-16 07:00:33
When using HEAD from
https://git.kernel.org/cgit/utils/kernel/ipvsadm/ipvsadm.git/,
the command:
ipvsadm --start-daemon backup --mcast-interface eth0.60 \
--mcast-group ff02::1:81
fails with the error message:
Argument list too long
whereas both:
ipvsadm --start-daemon master --mcast-interface eth0.60 \
--mcast-group ff02::1:81
and:
ipvsadm --start-daemon backup --mcast-interface eth0.60 \
--mcast-group 224.0.0.81
are successful.
The error message "Argument list too long" isn't helpful. The error occurs
because an IPv6 address is given in backup mode.
The error is in make_receive_sock() in net/netfilter/ipvs/ip_vs_sync.c,
since it fails to set the interface on the address or the socket before
calling inet6_bind() (via sock->ops->bind), where the test
'if (!sk->sk_bound_dev_if)' failed.
Setting sock->sk->sk_bound_dev_if on the socket before calling
inet6_bind() resolves the issue.
Fixes: d33288172e72 ("ipvs: add more mcast parameters for the sync daemon")
Signed-off-by: Quentin Armitage <redacted>
---
net/netfilter/ipvs/ip_vs_sync.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 803001a..1b07578 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c@@ -1545,7 +1545,8 @@ error: /* * Set up receiving multicast socket over UDP */ -static struct socket *make_receive_sock(struct netns_ipvs *ipvs, int id) +static struct socket *make_receive_sock(struct netns_ipvs *ipvs, int id, + int ifindex) { /* multicast addr */ union ipvs_sockaddr mcast_addr;
@@ -1566,6 +1567,7 @@ static struct socket *make_receive_sock(struct netns_ipvs *ipvs, int id) set_sock_size(sock->sk, 0, result); get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->bcfg, id); + sock->sk->sk_bound_dev_if = ifindex; result = sock->ops->bind(sock, (struct sockaddr *)&mcast_addr, salen); if (result < 0) { pr_err("Error binding to the multicast addr\n");
@@ -1868,7 +1870,7 @@ int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *c, if (state == IP_VS_STATE_MASTER) sock = make_send_sock(ipvs, id); else - sock = make_receive_sock(ipvs, id); + sock = make_receive_sock(ipvs, id, dev->ifindex); if (IS_ERR(sock)) { result = PTR_ERR(sock); goto outtinfo;
--
1.7.7.6