From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH net v4] sctp: asconf's process should verify address parameter is in the beginning Date: Thu, 27 Aug 2015 08:46:15 -0400 Message-ID: <55DF0697.5050608@gmail.com> References: <842bb5735d0ea0e632695f49dc85021faa176784.1440663994.git.lucien.xin@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: mleitner@redhat.com, davem@davemloft.net To: Xin Long , network dev Return-path: Received: from mail-qg0-f45.google.com ([209.85.192.45]:35391 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754586AbbH0MqX (ORCPT ); Thu, 27 Aug 2015 08:46:23 -0400 Received: by qgj62 with SMTP id 62so9814333qgj.2 for ; Thu, 27 Aug 2015 05:46:23 -0700 (PDT) In-Reply-To: <842bb5735d0ea0e632695f49dc85021faa176784.1440663994.git.lucien.xin@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On 08/27/2015 04:26 AM, Xin Long wrote: > in sctp_process_asconf(), we get address parameter from the beginning of > the addip params. but we never check if it's really there. if the addr > param is not there, it still can pass sctp_verify_asconf(), then to be > handled by sctp_process_asconf(), it will not be safe. > > so add a code in sctp_verify_asconf() to check the address parameter is in > the beginning, or return false to send abort. > > note that this can also detect multiple address parameters, and reject it. > > Signed-off-by: Xin Long > Signed-off-by: Marcelo Ricardo Leitner Looks good to me. Acked-by: Vlad Yasevich -vlad > --- > net/sctp/sm_make_chunk.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c > index 06320c8..a655ddc 100644 > --- a/net/sctp/sm_make_chunk.c > +++ b/net/sctp/sm_make_chunk.c > @@ -3132,11 +3132,18 @@ bool sctp_verify_asconf(const struct sctp_association *asoc, > case SCTP_PARAM_IPV4_ADDRESS: > if (length != sizeof(sctp_ipv4addr_param_t)) > return false; > + /* ensure there is only one addr param and it's in the > + * beginning of addip_hdr params, or we reject it. > + */ > + if (param.v != addip->addip_hdr.params) > + return false; > addr_param_seen = true; > break; > case SCTP_PARAM_IPV6_ADDRESS: > if (length != sizeof(sctp_ipv6addr_param_t)) > return false; > + if (param.v != addip->addip_hdr.params) > + return false; > addr_param_seen = true; > break; > case SCTP_PARAM_ADD_IP: >