From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [PATCH net] sctp: do not check port in sctp_inet6_cmp_addr Date: Wed, 11 Apr 2018 11:59:10 -0300 Message-ID: <20180411145910.GC3711@localhost.localdomain> References: <340aad3be762046ca9d02e54edba5bfefa2f4e71.1523451485.git.lucien.xin@gmail.com> <20180411143607.GA4141@hmswarspite.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Xin Long , network dev , linux-sctp@vger.kernel.org, davem@davemloft.net To: Neil Horman Return-path: Received: from mail-qt0-f193.google.com ([209.85.216.193]:45240 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752938AbeDKO7O (ORCPT ); Wed, 11 Apr 2018 10:59:14 -0400 Content-Disposition: inline In-Reply-To: <20180411143607.GA4141@hmswarspite.think-freely.org> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Apr 11, 2018 at 10:36:07AM -0400, Neil Horman wrote: > On Wed, Apr 11, 2018 at 08:58:05PM +0800, Xin Long wrote: > > 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 > > Signed-off-by: Xin Long > > --- > > 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 > > > This looks correct to me, but is it worth duplicating the comparison code like > this from the cmp_addr function? It might be more worthwhile to add a flag to > the cmp_addr method to direct weather it needs to check port values or not. > That way you could continue to use the cmp_addr function here. Adding a flag into sctp_v6_cmp_addr will get us a terrible code to read. It's already not one of the best looking part of it. Maybe still duplicate part of it it, but at 'af' level? As in: - af->cmp_addr - af->cmp_addr_port Marcelo From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Date: Wed, 11 Apr 2018 14:59:10 +0000 Subject: Re: [PATCH net] sctp: do not check port in sctp_inet6_cmp_addr Message-Id: <20180411145910.GC3711@localhost.localdomain> List-Id: References: <340aad3be762046ca9d02e54edba5bfefa2f4e71.1523451485.git.lucien.xin@gmail.com> <20180411143607.GA4141@hmswarspite.think-freely.org> In-Reply-To: <20180411143607.GA4141@hmswarspite.think-freely.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Neil Horman Cc: Xin Long , network dev , linux-sctp@vger.kernel.org, davem@davemloft.net On Wed, Apr 11, 2018 at 10:36:07AM -0400, Neil Horman wrote: > On Wed, Apr 11, 2018 at 08:58:05PM +0800, Xin Long wrote: > > 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 > > Signed-off-by: Xin Long > > --- > > 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 > > > This looks correct to me, but is it worth duplicating the comparison code like > this from the cmp_addr function? It might be more worthwhile to add a flag to > the cmp_addr method to direct weather it needs to check port values or not. > That way you could continue to use the cmp_addr function here. Adding a flag into sctp_v6_cmp_addr will get us a terrible code to read. It's already not one of the best looking part of it. Maybe still duplicate part of it it, but at 'af' level? As in: - af->cmp_addr - af->cmp_addr_port Marcelo