From owner-svn-src-head@freebsd.org Sat Jul 13 12:45:10 2019 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 26DAE15E8998; Sat, 13 Jul 2019 12:45:10 +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 BBFFB850A2; Sat, 13 Jul 2019 12:45:09 +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 57A1625FF7; Sat, 13 Jul 2019 12:45:09 +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 x6DCj90d050355; Sat, 13 Jul 2019 12:45:09 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x6DCj9iK050354; Sat, 13 Jul 2019 12:45:09 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201907131245.x6DCj9iK050354@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Sat, 13 Jul 2019 12:45:09 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r349968 - head/sys/netinet6 X-SVN-Group: head X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: head/sys/netinet6 X-SVN-Commit-Revision: 349968 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: BBFFB850A2 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.96 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; NEURAL_HAM_SHORT(-0.96)[-0.960,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] 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: Sat, 13 Jul 2019 12:45:10 -0000 Author: tuexen Date: Sat Jul 13 12:45:08 2019 New Revision: 349968 URL: https://svnweb.freebsd.org/changeset/base/349968 Log: r348494 fixes a race in udp_output(). The same race exists in udp_output6(), therefore apply a similar patch to IPv6. Reported by: syzbot+c5ffbc8f14294c7b0e54@syzkaller.appspotmail.com Reviewed by: bz@, markj@ MFC after: 2 weeks Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D20936 Modified: head/sys/netinet6/udp6_usrreq.c Modified: head/sys/netinet6/udp6_usrreq.c ============================================================================== --- head/sys/netinet6/udp6_usrreq.c Sat Jul 13 10:46:01 2019 (r349967) +++ head/sys/netinet6/udp6_usrreq.c Sat Jul 13 12:45:08 2019 (r349968) @@ -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);