From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [PATCH net] sctp: check af before verify address in sctp_addr_id2transport Date: Tue, 7 Feb 2017 10:58:55 -0200 Message-ID: <20170207125855.GB3414@localhost.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: network dev , linux-sctp@vger.kernel.org, davem@davemloft.net, Neil Horman , Vlad Yasevich To: Xin Long Return-path: Received: from mx1.redhat.com ([209.132.183.28]:38738 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754015AbdBGM7D (ORCPT ); Tue, 7 Feb 2017 07:59:03 -0500 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Feb 07, 2017 at 08:56:08PM +0800, Xin Long wrote: > Commit 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the > addr before looking up assoc") invoked sctp_verify_addr to verify the > addr. > > But it didn't check af variable beforehand, once users pass an address > with family = 0 through sockopt, sctp_get_af_specific will return NULL > and NULL pointer dereference will be caused by af->sockaddr_len. > > This patch is to fix it by returning NULL if af variable is NULL. > > Fixes: 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the addr before looking up assoc") > Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner > --- > net/sctp/socket.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/sctp/socket.c b/net/sctp/socket.c > index 37eeab7..f354375 100644 > --- a/net/sctp/socket.c > +++ b/net/sctp/socket.c > @@ -239,7 +239,7 @@ static struct sctp_transport *sctp_addr_id2transport(struct sock *sk, > union sctp_addr *laddr = (union sctp_addr *)addr; > struct sctp_transport *transport; > > - if (sctp_verify_addr(sk, laddr, af->sockaddr_len)) > + if (!af || sctp_verify_addr(sk, laddr, af->sockaddr_len)) > return NULL; > > addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep, > -- > 2.1.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-sctp" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >