From owner-svn-src-stable@freebsd.org Wed Jul 1 21:52:14 2020 Return-Path: Delivered-To: svn-src-stable@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id E840F35CB05; Wed, 1 Jul 2020 21:52:14 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 49xw1V5rnFz3bFY; Wed, 1 Jul 2020 21:52:14 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id AC3EB10406; Wed, 1 Jul 2020 21:52:14 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 061LqEBf029548; Wed, 1 Jul 2020 21:52:14 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 061LqE6i029546; Wed, 1 Jul 2020 21:52:14 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <202007012152.061LqE6i029546@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Wed, 1 Jul 2020 21:52:14 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r362872 - stable/12/sys/netinet X-SVN-Group: stable-12 X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: stable/12/sys/netinet X-SVN-Commit-Revision: 362872 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Jul 2020 21:52:15 -0000 Author: tuexen Date: Wed Jul 1 21:52:14 2020 New Revision: 362872 URL: https://svnweb.freebsd.org/changeset/base/362872 Log: MFC r356270: Improve input validation of the spp_pathmtu field in the SCTP_PEER_ADDR_PARAMS socket option. The code in the stack assumes sane values for the MTU. This issue was found by running an instance of syzkaller. MFC r356271: Remove empty line which was added in previous commit by accident. Modified: stable/12/sys/netinet/sctp.h stable/12/sys/netinet/sctp_usrreq.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/netinet/sctp.h ============================================================================== --- stable/12/sys/netinet/sctp.h Wed Jul 1 21:48:17 2020 (r362871) +++ stable/12/sys/netinet/sctp.h Wed Jul 1 21:52:14 2020 (r362872) @@ -585,8 +585,10 @@ struct sctp_error_auth_invalid_hmac { #define SCTP_MOBILITY_PRIM_DELETED 0x00000004 -#define SCTP_SMALLEST_PMTU 512 /* smallest pmtu allowed when disabling PMTU - * discovery */ +/* Smallest PMTU allowed when disabling PMTU discovery */ +#define SCTP_SMALLEST_PMTU 512 +/* Largest PMTU allowed when disabling PMTU discovery */ +#define SCTP_LARGEST_PMTU 65536 #undef SCTP_PACKED Modified: stable/12/sys/netinet/sctp_usrreq.c ============================================================================== --- stable/12/sys/netinet/sctp_usrreq.c Wed Jul 1 21:48:17 2020 (r362871) +++ stable/12/sys/netinet/sctp_usrreq.c Wed Jul 1 21:52:14 2020 (r362872) @@ -5363,6 +5363,14 @@ sctp_setopt(struct socket *so, int optname, void *optv SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, EINVAL); return (EINVAL); } + if ((paddrp->spp_flags & SPP_PMTUD_DISABLE) && + ((paddrp->spp_pathmtu < SCTP_SMALLEST_PMTU) || + (paddrp->spp_pathmtu > SCTP_LARGEST_PMTU))) { + if (stcb) + SCTP_TCB_UNLOCK(stcb); + SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, EINVAL); + return (EINVAL); + } if (stcb != NULL) { /************************TCB SPECIFIC SET ******************/ @@ -5394,7 +5402,7 @@ sctp_setopt(struct socket *so, int optname, void *optv sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net); } } - if ((paddrp->spp_flags & SPP_PMTUD_DISABLE) && (paddrp->spp_pathmtu >= SCTP_SMALLEST_PMTU)) { + if (paddrp->spp_flags & SPP_PMTUD_DISABLE) { if (SCTP_OS_TIMER_PENDING(&net->pmtu_timer.timer)) { sctp_timer_stop(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net, SCTP_FROM_SCTP_USRREQ + SCTP_LOC_11); @@ -5536,7 +5544,7 @@ sctp_setopt(struct socket *so, int optname, void *optv } sctp_stcb_feature_on(inp, stcb, SCTP_PCB_FLAGS_DONOT_HEARTBEAT); } - if ((paddrp->spp_flags & SPP_PMTUD_DISABLE) && (paddrp->spp_pathmtu >= SCTP_SMALLEST_PMTU)) { + if (paddrp->spp_flags & SPP_PMTUD_DISABLE) { TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { if (SCTP_OS_TIMER_PENDING(&net->pmtu_timer.timer)) { sctp_timer_stop(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net, @@ -5635,9 +5643,7 @@ sctp_setopt(struct socket *so, int optname, void *optv inp->sctp_ep.default_mtu = 0; sctp_feature_off(inp, SCTP_PCB_FLAGS_DO_NOT_PMTUD); } else if (paddrp->spp_flags & SPP_PMTUD_DISABLE) { - if (paddrp->spp_pathmtu >= SCTP_SMALLEST_PMTU) { - inp->sctp_ep.default_mtu = paddrp->spp_pathmtu; - } + inp->sctp_ep.default_mtu = paddrp->spp_pathmtu; sctp_feature_on(inp, SCTP_PCB_FLAGS_DO_NOT_PMTUD); } if (paddrp->spp_flags & SPP_DSCP) {