From owner-svn-src-head@freebsd.org Mon May 14 13:50:18 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 28850DBB8C6; Mon, 14 May 2018 13:50:18 +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 TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D08CF7E13D; Mon, 14 May 2018 13:50:17 +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 913D81CE44; Mon, 14 May 2018 13:50:17 +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 w4EDoHHG033835; Mon, 14 May 2018 13:50:17 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w4EDoH6V033834; Mon, 14 May 2018 13:50:17 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201805141350.w4EDoH6V033834@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Mon, 14 May 2018 13:50:17 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r333603 - head/sys/netinet X-SVN-Group: head X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: head/sys/netinet X-SVN-Commit-Revision: 333603 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 May 2018 13:50:18 -0000 Author: tuexen Date: Mon May 14 13:50:17 2018 New Revision: 333603 URL: https://svnweb.freebsd.org/changeset/base/333603 Log: Ensure that the MTU's used are multiple of 4. The length of SCTP packets is always a multiple of 4. Therefore, ensure that the MTUs used are also a multiple of 4. Thanks to Irene Ruengeler for providing an earlier version of this patch. MFC after: 1 week Modified: head/sys/netinet/sctputil.c Modified: head/sys/netinet/sctputil.c ============================================================================== --- head/sys/netinet/sctputil.c Mon May 14 07:20:34 2018 (r333602) +++ head/sys/netinet/sctputil.c Mon May 14 13:50:17 2018 (r333603) @@ -758,8 +758,8 @@ sctp_stop_timers_for_shutdown(struct sctp_tcb *stcb) } /* - * a list of sizes based on typical mtu's, used only if next hop size not - * returned. + * A list of sizes based on typical mtu's, used only if next hop size not + * returned. These values MUST be multiples of 4 and MUST be ordered. */ static uint32_t sctp_mtu_sizes[] = { 68, @@ -768,29 +768,32 @@ static uint32_t sctp_mtu_sizes[] = { 512, 544, 576, - 1006, + 1004, 1492, 1500, 1536, - 2002, + 2000, 2048, 4352, 4464, 8166, - 17914, + 17912, 32000, - 65535 + 65532 }; /* - * Return the largest MTU smaller than val. If there is no - * entry, just return val. + * Return the largest MTU in sctp_mtu_sizes smaller than val. + * If val is smaller than the minimum, just return the largest + * multiple of 4 smaller or equal to val. + * Ensure that the result is a multiple of 4. */ uint32_t sctp_get_prev_mtu(uint32_t val) { uint32_t i; + val &= 0x00000003; if (val <= sctp_mtu_sizes[0]) { return (val); } @@ -799,12 +802,16 @@ sctp_get_prev_mtu(uint32_t val) break; } } + KASSERT((sctp_mtu_sizes[i - 1] & 0x00000003) == 0, + ("sctp_mtu_sizes[%u] not a multiple of 4", i - 1)); return (sctp_mtu_sizes[i - 1]); } /* - * Return the smallest MTU larger than val. If there is no - * entry, just return val. + * Return the smallest MTU in sctp_mtu_sizes larger than val. + * If val is larger than the maximum, just return the largest multiple of 4 smaller + * or equal to val. + * Ensure that the result is a multiple of 4. */ uint32_t sctp_get_next_mtu(uint32_t val) @@ -812,8 +819,11 @@ sctp_get_next_mtu(uint32_t val) /* select another MTU that is just bigger than this one */ uint32_t i; + val &= 0x00000003; for (i = 0; i < (sizeof(sctp_mtu_sizes) / sizeof(uint32_t)); i++) { if (val < sctp_mtu_sizes[i]) { + KASSERT((sctp_mtu_sizes[i] & 0x00000003) == 0, + ("sctp_mtu_sizes[%u] not a multiple of 4", i)); return (sctp_mtu_sizes[i]); } }