From owner-svn-src-head@freebsd.org Wed Apr 29 22:01:34 2020 Return-Path: Delivered-To: svn-src-head@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 985E42C4257; Wed, 29 Apr 2020 22:01:34 +0000 (UTC) (envelope-from rscheff@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) server-signature RSA-PSS (4096 bits) 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 49CCCL3Z1Yz3NY8; Wed, 29 Apr 2020 22:01:34 +0000 (UTC) (envelope-from rscheff@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 5B8AAC89B; Wed, 29 Apr 2020 22:01:34 +0000 (UTC) (envelope-from rscheff@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 03TM1Y1Y031149; Wed, 29 Apr 2020 22:01:34 GMT (envelope-from rscheff@FreeBSD.org) Received: (from rscheff@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 03TM1XgU031146; Wed, 29 Apr 2020 22:01:33 GMT (envelope-from rscheff@FreeBSD.org) Message-Id: <202004292201.03TM1XgU031146@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: rscheff set sender to rscheff@FreeBSD.org using -f From: Richard Scheffenegger Date: Wed, 29 Apr 2020 22:01:33 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r360479 - in head/sys/netinet: . tcp_stacks X-SVN-Group: head X-SVN-Commit-Author: rscheff X-SVN-Commit-Paths: in head/sys/netinet: . tcp_stacks X-SVN-Commit-Revision: 360479 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: 2.1.29 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: Wed, 29 Apr 2020 22:01:34 -0000 Author: rscheff Date: Wed Apr 29 22:01:33 2020 New Revision: 360479 URL: https://svnweb.freebsd.org/changeset/base/360479 Log: Prevent premature shrinking of the scaled receive window which can cause a TCP client to use invalid or stale TCP sequence numbers for ACK packets. Packets with old sequence numbers are ignored and not used to update the send window size. This might cause the TCP session to hang indefinitely under some circumstances. Reported by: Cui Cheng Reviewed by: tuexen (mentor), rgrimes (mentor) Approved by: tuexen (mentor), rgrimes (mentor) MFC after: 3 weeks Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D24515 Modified: head/sys/netinet/tcp_output.c head/sys/netinet/tcp_stacks/bbr.c head/sys/netinet/tcp_stacks/rack.c Modified: head/sys/netinet/tcp_output.c ============================================================================== --- head/sys/netinet/tcp_output.c Wed Apr 29 21:54:09 2020 (r360478) +++ head/sys/netinet/tcp_output.c Wed Apr 29 22:01:33 2020 (r360479) @@ -1238,8 +1238,11 @@ send: if (flags & TH_SYN) th->th_win = htons((u_short) (min(sbspace(&so->so_rcv), TCP_MAXWIN))); - else + else { + /* Avoid shrinking window with window scaling. */ + recwin = roundup2(recwin, 1 << tp->rcv_scale); th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); + } /* * Adjust the RXWIN0SENT flag - indicate that we have advertised Modified: head/sys/netinet/tcp_stacks/bbr.c ============================================================================== --- head/sys/netinet/tcp_stacks/bbr.c Wed Apr 29 21:54:09 2020 (r360478) +++ head/sys/netinet/tcp_stacks/bbr.c Wed Apr 29 22:01:33 2020 (r360479) @@ -13756,8 +13756,11 @@ send: if (flags & TH_SYN) th->th_win = htons((u_short) (min(sbspace(&so->so_rcv), TCP_MAXWIN))); - else + else { + /* Avoid shrinking window with window scaling. */ + recwin = roundup2(recwin, 1 << tp->rcv_scale); th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); + } /* * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0 * window. This may cause the remote transmitter to stall. This Modified: head/sys/netinet/tcp_stacks/rack.c ============================================================================== --- head/sys/netinet/tcp_stacks/rack.c Wed Apr 29 21:54:09 2020 (r360478) +++ head/sys/netinet/tcp_stacks/rack.c Wed Apr 29 22:01:33 2020 (r360479) @@ -9572,8 +9572,11 @@ send: if (flags & TH_SYN) th->th_win = htons((u_short) (min(sbspace(&so->so_rcv), TCP_MAXWIN))); - else + else { + /* Avoid shrinking window with window scaling. */ + recwin = roundup2(recwin, 1 << tp->rcv_scale); th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); + } /* * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0 * window. This may cause the remote transmitter to stall. This