From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-4046011-1517256728-2-10286230868400691013 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1517256728; b=Vw4qv232E+XoO17vV93SujuchyacR3O5pKFkUXM7YKPLECB /k60VpWLjQ+IeYg8fnuoRpDA/ZNCaPYgP8LiUCQO9KGeOEcGJdGloip+rst1fbkX yqQgj5aGGSP1xITG6riCv6XFgeixHaV16PEboqmVdv2YEhOmF5Lej8pT6NE1+X9i 7XeguAWkh4Mh0X99hF7eElFIeNK7YEbD6WJTrAbvFqZqHLkTE6bBpRMmdhSP4JyB 04y/j0aTKcJeXc9ZCgBdU4++i6/+9yg0WO8nD+QLclDiQ1TZL7dfEc5O/YisQovO piYlxH1rz/lda/XY29SZom4+Q5cfokCT19xQtvw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1517256728; bh=j7fKgw6nbGVQWlIj19Wj0jynpq AKVMWXbrDV2Pd+OJE=; b=d3NVS7DKZR6+p82gbueVynawKs080dwpkSFe6Yyl9T LQHGUkpP99K72Oc4FoNTj6bCaciq6+AFr9wn/3zaQy99cymTaIO0e5Fj/CcK8U9F 0qZ9wyEPS0Nb59K0FYoLOTf8xhZkGN4oGZtgvqtsCxjuGhokMt08RaN6bT5nAFPd Tfy8wh9uGN+J2qzZQU7ZZLaaL06V1NFgX0hWlTmYVf4vHYNcpmCVdTN/qNu4TZYc ln/LrBP0vJYaXf4iSvED5oE7/JzJtsXlu+rzhbFzRe2PybD408odUQOd4CEG9Fv6 +3L4YydMMCv6sSN9uV+/ILtWwLacHkAdj30eF8D0mxrg== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753556AbeA2UMF (ORCPT ); Mon, 29 Jan 2018 15:12:05 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:33950 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753886AbeA2UME (ORCPT ); Mon, 29 Jan 2018 15:12:04 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+7b7b518b1228d2743963@syzkaller.appspotmail.com, Neil Horman , Xin Long , Marcelo Ricardo Leitner , "David S. Miller" Subject: [PATCH 4.9 43/66] sctp: do not allow the v4 socket to bind a v4mapped v6 address Date: Mon, 29 Jan 2018 13:57:07 +0100 Message-Id: <20180129123842.154208303@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180129123839.842860149@linuxfoundation.org> References: <20180129123839.842860149@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit c5006b8aa74599ce19104b31d322d2ea9ff887cc ] The check in sctp_sockaddr_af is not robust enough to forbid binding a v4mapped v6 addr on a v4 socket. The worse thing is that v4 socket's bind_verify would not convert this v4mapped v6 addr to a v4 addr. syzbot even reported a crash as the v4 socket bound a v6 addr. This patch is to fix it by doing the common sa.sa_family check first, then AF_INET check for v4mapped v6 addrs. Fixes: 7dab83de50c7 ("sctp: Support ipv6only AF_INET6 sockets.") Reported-by: syzbot+7b7b518b1228d2743963@syzkaller.appspotmail.com Acked-by: Neil Horman Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/socket.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -332,16 +332,14 @@ static struct sctp_af *sctp_sockaddr_af( if (len < sizeof (struct sockaddr)) return NULL; + if (!opt->pf->af_supported(addr->sa.sa_family, opt)) + return NULL; + /* V4 mapped address are really of AF_INET family */ if (addr->sa.sa_family == AF_INET6 && - ipv6_addr_v4mapped(&addr->v6.sin6_addr)) { - if (!opt->pf->af_supported(AF_INET, opt)) - return NULL; - } else { - /* Does this PF support this AF? */ - if (!opt->pf->af_supported(addr->sa.sa_family, opt)) - return NULL; - } + ipv6_addr_v4mapped(&addr->v6.sin6_addr) && + !opt->pf->af_supported(AF_INET, opt)) + return NULL; /* If we get this far, af is valid. */ af = sctp_get_af_specific(addr->sa.sa_family);