Commit 1071ec9d authored by Xin Long's avatar Xin Long Committed by David S. Miller
Browse files

sctp: do not check port in sctp_inet6_cmp_addr 



pf->cmp_addr() is called before binding a v6 address to the sock. It
should not check ports, like in sctp_inet_cmp_addr.

But sctp_inet6_cmp_addr checks the addr by invoking af(6)->cmp_addr,
sctp_v6_cmp_addr where it also compares the ports.

This would cause that setsockopt(SCTP_SOCKOPT_BINDX_ADD) could bind
multiple duplicated IPv6 addresses after Commit 40b4f0fd ("sctp:
lack the check for ports in sctp_v6_cmp_addr").

This patch is to remove af->cmp_addr called in sctp_inet6_cmp_addr,
but do the proper check for both v6 addrs and v4mapped addrs.

v1->v2:
  - define __sctp_v6_cmp_addr to do the common address comparison
    used for both pf and af v6 cmp_addr.

Fixes: 40b4f0fd ("sctp: lack the check for ports in sctp_v6_cmp_addr")
Reported-by: default avatarJianwen Ji <jiji@redhat.com>
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 837708a8

net/sctp/ipv6.c

+30 −30
Original line number Diff line number Diff line
@@ -556,46 +556,49 @@ static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 
	addr->v6.sin6_scope_id = 0;

}



/* Compare addresses exactly.

 * v4-mapped-v6 is also in consideration.

 */

static int sctp_v6_cmp_addr(const union sctp_addr *addr1,

static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,

			      const union sctp_addr *addr2)

{

	if (addr1->sa.sa_family != addr2->sa.sa_family) {

		if (addr1->sa.sa_family == AF_INET &&

		    addr2->sa.sa_family == AF_INET6 &&

		    ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {

			if (addr2->v6.sin6_port == addr1->v4.sin_port &&

		    ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&

		    addr2->v6.sin6_addr.s6_addr32[3] ==

		    addr1->v4.sin_addr.s_addr)

			return 1;

		}



		if (addr2->sa.sa_family == AF_INET &&

		    addr1->sa.sa_family == AF_INET6 &&

		    ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {

			if (addr1->v6.sin6_port == addr2->v4.sin_port &&

		    ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&

		    addr1->v6.sin6_addr.s6_addr32[3] ==

		    addr2->v4.sin_addr.s_addr)

			return 1;

		}



		return 0;

	}

	if (addr1->v6.sin6_port != addr2->v6.sin6_port)

		return 0;



	if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))

		return 0;



	/* If this is a linklocal address, compare the scope_id. */

	if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {

		if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&

		    (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {

	if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&

	    addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&

	    addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)

		return 0;

		}

	}



	return 1;

}



/* Compare addresses exactly.

 * v4-mapped-v6 is also in consideration.

 */

static int sctp_v6_cmp_addr(const union sctp_addr *addr1,

			    const union sctp_addr *addr2)

{

	return __sctp_v6_cmp_addr(addr1, addr2) &&

	       addr1->v6.sin6_port == addr2->v6.sin6_port;

}



/* Initialize addr struct to INADDR_ANY. */

static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)

{
@@ -875,8 +878,8 @@ static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 
			       const union sctp_addr *addr2,

			       struct sctp_sock *opt)

{

	struct sctp_af *af1, *af2;

	struct sock *sk = sctp_opt2sk(opt);

	struct sctp_af *af1, *af2;



	af1 = sctp_get_af_specific(addr1->sa.sa_family);

	af2 = sctp_get_af_specific(addr2->sa.sa_family);
@@ -892,10 +895,7 @@ static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 
	if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))

		return 1;



	if (addr1->sa.sa_family != addr2->sa.sa_family)

		return 0;



	return af1->cmp_addr(addr1, addr2);

	return __sctp_v6_cmp_addr(addr1, addr2);

}



/* Verify that the provided sockaddr looks bindable.   Common verification,

CRA Git | Maintained and supported by SUSTech CRA and CCSE