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. Fixes: 40b4f0fd74e4 ("sctp: lack the check for ports in sctp_v6_cmp_addr") Reported-by: Jianwen Ji <jiji@xxxxxxxxxx> Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> --- net/sctp/ipv6.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index f1fc48e..be4b72c 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -846,8 +846,8 @@ 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); @@ -863,10 +863,31 @@ 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) + 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_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_addr.s6_addr32[3] == + addr2->v4.sin_addr.s_addr) + return 1; + return 0; + } + + if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) + 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 af1->cmp_addr(addr1, addr2); + return 1; } /* Verify that the provided sockaddr looks bindable. Common verification, -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html