From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH net] net: sctp: fix copying sk_v6_rcv_saddr in sctp_v6_create_accept_sk Date: Thu, 21 Nov 2013 10:08:00 +0100 Message-ID: <528DCD70.6060306@redhat.com> References: <1384858284-2246-1-git-send-email-dborkman@redhat.com> <528B85E2.5080403@gmail.com> <528DAD15.20901@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Vlad Yasevich , davem@davemloft.net, netdev@vger.kernel.org, linux-sctp@vger.kernel.org, Eric Dumazet To: wangweidong Return-path: Received: from mx1.redhat.com ([209.132.183.28]:7757 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753337Ab3KUJIM (ORCPT ); Thu, 21 Nov 2013 04:08:12 -0500 In-Reply-To: <528DAD15.20901@huawei.com> Sender: netdev-owner@vger.kernel.org List-ID: On 11/21/2013 07:49 AM, wangweidong wrote: > On 2013/11/19 23:38, Vlad Yasevich wrote: >> On 11/19/2013 05:51 AM, Daniel Borkmann wrote: >>> Wang reported an issue that lksctp's test_getname_v6 seems to fail. >>> >>> The issue is that we do not copy sk_v6_rcv_saddr over to the new >>> socket, although the comment above says so regarding rcv_saddr. >>> >>> Commit 914e1c8b6980 ("sctp: Inherit all socket options from parent >>> correctly.") originally moved that over to sctp_copy_sock(), but >>> after commit efe4208f47f9 ("ipv6: make lookups simpler and faster") >>> this no longer holds and the actual value of sk_v6_rcv_saddr was >>> no longer being migrated. >>> >>> With this patch, the lksctp test suite passes again for IPv6. >>> >>> Fixes: efe4208f47f9 ("ipv6: make lookups simpler and faster") >>> Signed-off-by: Daniel Borkmann >>> Signed-off-by: Wang Weidong >>> Cc: Eric Dumazet >>> --- >>> net/sctp/ipv6.c | 1 + >>> 1 file changed, 1 insertion(+) >>> >>> diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c >>> index 7567e6f..be08592 100644 >>> --- a/net/sctp/ipv6.c >>> +++ b/net/sctp/ipv6.c >>> @@ -661,6 +661,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, >>> * and getpeername(). >>> */ >>> sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); >>> + newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; >>> >>> sk_refcnt_debug_inc(newsk); >>> >>> >> >> This fixes the issue for the accept() case, but the bug is still there >> in the peeloff case. >> >> I think you should make sctp_copy_sock() use sock_copy() for now. It >> looks like it will catch all the cases. >> > > I copied the part of the sock_copy() codes into sctp_v6_create_accept_sk instead of > sctp_copy_sock for testing. Like this: > > -------------- > > @@ -645,7 +645,11 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, > > sock_init_data(NULL, newsk); > > - sctp_copy_sock(newsk, sk, asoc); > + memcpy(newsk, sk, offsetof(struct sock, sk_dontcopy_begin)); > + > + memcpy(&newsk->sk_dontcopy_end, &sk->sk_dontcopy_end, > + sk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); > + > sock_reset_flag(sk, SOCK_ZAPPED); > > newsctp6sk = (struct sctp6_sock *)newsk; > > -------------- > > when I did the test_getname_v6 of lksctp tools. It would hang. And I used the ps aux, > I can see the process got a D+ STAT. > > BTW, I test it in the virtual machine. > > So I think: when we use the sock_copy or which calls it, maybe we will get the problem here. > Is there I do something wrong? Sorry, got distracted with other things in the mean time. I will have a closer look at it very soon, so that we can find a proper fix. > Thanks. > >> We can then look at possibly getting rid of sctp_copy_sock() for net-next. >> >> -vlad >> >> >> > > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >