From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [PATCH net] sctp: init active key for the new asoc in dupcook_a and dupcook_b Date: Wed, 2 May 2018 09:04:25 -0300 Message-ID: <20180502120425.GF4977@localhost.localdomain> References: <96c2191206cb67ccec250ca1ec66d83dc9f40c9a.1525239464.git.lucien.xin@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: network dev , linux-sctp@vger.kernel.org, davem@davemloft.net, Neil Horman To: Xin Long Return-path: Received: from mail-qt0-f196.google.com ([209.85.216.196]:44120 "EHLO mail-qt0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751216AbeEBME3 (ORCPT ); Wed, 2 May 2018 08:04:29 -0400 Content-Disposition: inline In-Reply-To: <96c2191206cb67ccec250ca1ec66d83dc9f40c9a.1525239464.git.lucien.xin@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, May 02, 2018 at 01:37:44PM +0800, Xin Long wrote: > When processing a duplicate cookie-echo chunk, for case 'A' and 'B', > after sctp_process_init for the new asoc, if auth is enabled for the > cookie-ack chunk, the active key should also be initialized. > > Otherwise, the cookie-ack chunk made later can not be set with auth > shkey properly, and a crash can even be caused by this, as after > Commit 1b1e0bc99474 ("sctp: add refcnt support for sh_key"), sctp > needs to hold the shkey when making control chunks. > > Fixes: 1b1e0bc99474 ("sctp: add refcnt support for sh_key") > Reported-by: Jianwen Ji > Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner > --- > net/sctp/sm_statefuns.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c > index dd0594a..98acfed 100644 > --- a/net/sctp/sm_statefuns.c > +++ b/net/sctp/sm_statefuns.c > @@ -1794,6 +1794,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_a( > GFP_ATOMIC)) > goto nomem; > > + if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) > + goto nomem; > + > /* Make sure no new addresses are being added during the > * restart. Though this is a pretty complicated attack > * since you'd have to get inside the cookie. > @@ -1906,6 +1909,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_b( > GFP_ATOMIC)) > goto nomem; > > + if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) > + goto nomem; > + > /* Update the content of current association. */ > sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); > sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, > -- > 2.1.0 > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Date: Wed, 02 May 2018 12:04:25 +0000 Subject: Re: [PATCH net] sctp: init active key for the new asoc in dupcook_a and dupcook_b Message-Id: <20180502120425.GF4977@localhost.localdomain> List-Id: References: <96c2191206cb67ccec250ca1ec66d83dc9f40c9a.1525239464.git.lucien.xin@gmail.com> In-Reply-To: <96c2191206cb67ccec250ca1ec66d83dc9f40c9a.1525239464.git.lucien.xin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Xin Long Cc: network dev , linux-sctp@vger.kernel.org, davem@davemloft.net, Neil Horman On Wed, May 02, 2018 at 01:37:44PM +0800, Xin Long wrote: > When processing a duplicate cookie-echo chunk, for case 'A' and 'B', > after sctp_process_init for the new asoc, if auth is enabled for the > cookie-ack chunk, the active key should also be initialized. > > Otherwise, the cookie-ack chunk made later can not be set with auth > shkey properly, and a crash can even be caused by this, as after > Commit 1b1e0bc99474 ("sctp: add refcnt support for sh_key"), sctp > needs to hold the shkey when making control chunks. > > Fixes: 1b1e0bc99474 ("sctp: add refcnt support for sh_key") > Reported-by: Jianwen Ji > Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner > --- > net/sctp/sm_statefuns.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c > index dd0594a..98acfed 100644 > --- a/net/sctp/sm_statefuns.c > +++ b/net/sctp/sm_statefuns.c > @@ -1794,6 +1794,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_a( > GFP_ATOMIC)) > goto nomem; > > + if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) > + goto nomem; > + > /* Make sure no new addresses are being added during the > * restart. Though this is a pretty complicated attack > * since you'd have to get inside the cookie. > @@ -1906,6 +1909,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_b( > GFP_ATOMIC)) > goto nomem; > > + if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) > + goto nomem; > + > /* Update the content of current association. */ > sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); > sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, > -- > 2.1.0 >