Commit b8607805 authored Dec 20, 2016 by Xin Long Committed by David S. Miller Dec 20, 2016

sctp: not copying duplicate addrs to the assoc's bind address list



sctp.local_addr_list is a global address list that is supposed to include
all the local addresses. sctp updates this list according to NETDEV_UP/
NETDEV_DOWN notifications.

However, if multiple NICs have the same address, the global list would
have duplicate addresses. Even if for one NIC, promote secondaries in
__inet_del_ifa can also lead to accumulating duplicate addresses.

When sctp binds address 'ANY' and creates a connection, it copies all
the addresses from global list into asoc's bind addr list, which makes
sctp pack the duplicate addresses into INIT/INIT_ACK packets.

This patch is to filter the duplicate addresses when copying the addrs
from global list in sctp_copy_local_addr_list and unpacking addr_param
from cookie in sctp_raw_to_bind_addrs to asoc's bind addr list.

Note that we can't filter the duplicate addrs when global address list
gets updated, As NETDEV_DOWN event may remove an addr that still exists
in another NIC.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 165f2cf6

net/sctp/bind_addr.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -292,6 +292,8 @@ int sctp_raw_to_bind_addrs(struct sctp_bind_addr bp, __u8 raw_addr_list,
		}

		af->from_addr_param(&addr, rawaddr, htons(port), 0);
		if (sctp_bind_addr_state(bp, &addr) != -1)
		goto next;
		retval = sctp_add_bind_addr(bp, &addr, sizeof(addr),
		SCTP_ADDR_SRC, gfp);
		if (retval) {
		@@ -300,6 +302,7 @@ int sctp_raw_to_bind_addrs(struct sctp_bind_addr bp, __u8 raw_addr_list,
		break;
		}

		next:
		len = ntohs(param->length);
		addrs_len -= len;
		raw_addr_list += len;

net/sctp/protocol.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -220,6 +220,9 @@ int sctp_copy_local_addr_list(struct net net, struct sctp_bind_addr bp,
		!(copy_flags & SCTP_ADDR6_PEERSUPP)))
		continue;

		if (sctp_bind_addr_state(bp, &addr->a) != -1)
		continue;

		error = sctp_add_bind_addr(bp, &addr->a, sizeof(addr->a),
		SCTP_ADDR_SRC, GFP_ATOMIC);
		if (error)

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