From owner-svn-src-stable@freebsd.org Sat Sep 7 10:45:45 2019 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 610FDECA62; Sat, 7 Sep 2019 10:45:45 +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) 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 46QWL11lPgz4LsY; Sat, 7 Sep 2019 10:45:45 +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 205D045D8; Sat, 7 Sep 2019 10:45:45 +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 x87AjjFT012590; Sat, 7 Sep 2019 10:45:45 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x87AjjUR012589; Sat, 7 Sep 2019 10:45:45 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201909071045.x87AjjUR012589@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Sat, 7 Sep 2019 10:45:45 +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: r351971 - stable/12/sys/netinet6 X-SVN-Group: stable-12 X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: stable/12/sys/netinet6 X-SVN-Commit-Revision: 351971 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: 2.1.29 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: Sat, 07 Sep 2019 10:45:45 -0000 Author: tuexen Date: Sat Sep 7 10:45:44 2019 New Revision: 351971 URL: https://svnweb.freebsd.org/changeset/base/351971 Log: MFC r349968: r348494 fixes a race in udp_output(). The same race exists in udp_output6(), therefore apply a similar patch to IPv6. Reviewed by: bz@, markj@ Differential Revision: https://reviews.freebsd.org/D20936 Modified: stable/12/sys/netinet6/udp6_usrreq.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/netinet6/udp6_usrreq.c ============================================================================== --- stable/12/sys/netinet6/udp6_usrreq.c Sat Sep 7 10:39:49 2019 (r351970) +++ stable/12/sys/netinet6/udp6_usrreq.c Sat Sep 7 10:45:44 2019 (r351971) @@ -742,9 +742,24 @@ udp6_output(struct socket *so, int flags_arg, struct m * - when we are not bound to an address and source port (it is * in6_pcbsetport() which will require the write lock). */ +retry: if (sin6 == NULL || (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) && inp->inp_lport == 0)) { INP_WLOCK(inp); + /* + * In case we lost a race and another thread bound addr/port + * on the inp we cannot keep the wlock (which still would be + * fine) as further down, based on these values we make + * decisions for the pcbinfo lock. If the locks are not in + * synch the assertions on unlock will fire, hence we go for + * one retry loop. + */ + if (sin6 != NULL && + (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) || + inp->inp_lport != 0)) { + INP_WUNLOCK(inp); + goto retry; + } unlock_inp = UH_WLOCKED; } else { INP_RLOCK(inp);