4.4-stable review patch. If anyone has any objections, please let me know.
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From: Xin Long lucien.xin@gmail.com
[ Upstream commit 1071ec9d453a38023579714b64a951a2fb982071 ]
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 40b4f0fd74e4 ("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: 40b4f0fd74e4 ("sctp: lack the check for ports in sctp_v6_cmp_addr") Reported-by: Jianwen Ji jiji@redhat.com Signed-off-by: Xin Long lucien.xin@gmail.com Acked-by: Neil Horman nhorman@tuxdriver.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sctp/ipv6.c | 60 ++++++++++++++++++++++++++++---------------------------- 1 file changed, 30 insertions(+), 30 deletions(-)
--- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -519,46 +519,49 @@ static void sctp_v6_to_addr(union sctp_a 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, - const union sctp_addr *addr2) +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 && - addr2->v6.sin6_addr.s6_addr32[3] == - addr1->v4.sin_addr.s_addr) - return 1; - } + 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 && - addr1->v6.sin6_addr.s6_addr32[3] == - addr2->v4.sin_addr.s_addr) - return 1; - } + 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)) { - return 0; - } - } + 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) { @@ -843,8 +846,8 @@ static int sctp_inet6_cmp_addr(const uni 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); @@ -860,10 +863,7 @@ static int sctp_inet6_cmp_addr(const uni 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,