From owner-svn-src-all@freebsd.org Fri Jan 25 20:24:55 2019 Return-Path: Delivered-To: svn-src-all@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 E121F14C20CC; Fri, 25 Jan 2019 20:24:54 +0000 (UTC) (envelope-from markj@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 87B94711AF; Fri, 25 Jan 2019 20:24:54 +0000 (UTC) (envelope-from markj@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 5B3B0D645; Fri, 25 Jan 2019 20:24:54 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x0PKOskv003353; Fri, 25 Jan 2019 20:24:54 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x0PKOrYc003351; Fri, 25 Jan 2019 20:24:53 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201901252024.x0PKOrYc003351@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Fri, 25 Jan 2019 20:24:53 +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: r343454 - in stable/12/sys: netinet netinet6 X-SVN-Group: stable-12 X-SVN-Commit-Author: markj X-SVN-Commit-Paths: in stable/12/sys: netinet netinet6 X-SVN-Commit-Revision: 343454 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 87B94711AF X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.98 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.998,0]; NEURAL_HAM_SHORT(-0.98)[-0.981,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Jan 2019 20:24:55 -0000 Author: markj Date: Fri Jan 25 20:24:53 2019 New Revision: 343454 URL: https://svnweb.freebsd.org/changeset/base/343454 Log: MFC r343363, r343364: Fix an LLE lookup race. PR: 234296 Modified: stable/12/sys/netinet/in.c stable/12/sys/netinet6/in6.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/netinet/in.c ============================================================================== --- stable/12/sys/netinet/in.c Fri Jan 25 20:20:27 2019 (r343453) +++ stable/12/sys/netinet/in.c Fri Jan 25 20:24:53 2019 (r343454) @@ -1378,15 +1378,13 @@ in_lltable_lookup(struct lltable *llt, u_int flags, co IF_AFDATA_LOCK_ASSERT(llt->llt_ifp); KASSERT(l3addr->sa_family == AF_INET, ("sin_family %d", l3addr->sa_family)); - lle = in_lltable_find_dst(llt, sin->sin_addr); + KASSERT((flags & (LLE_UNLOCKED | LLE_EXCLUSIVE)) != + (LLE_UNLOCKED | LLE_EXCLUSIVE), + ("wrong lle request flags: %#x", flags)); + lle = in_lltable_find_dst(llt, sin->sin_addr); if (lle == NULL) return (NULL); - - KASSERT((flags & (LLE_UNLOCKED|LLE_EXCLUSIVE)) != - (LLE_UNLOCKED|LLE_EXCLUSIVE),("wrong lle request flags: 0x%X", - flags)); - if (flags & LLE_UNLOCKED) return (lle); @@ -1395,6 +1393,17 @@ in_lltable_lookup(struct lltable *llt, u_int flags, co else LLE_RLOCK(lle); + /* + * If the afdata lock is not held, the LLE may have been unlinked while + * we were blocked on the LLE lock. Check for this case. + */ + if (__predict_false((lle->la_flags & LLE_LINKED) == 0)) { + if (flags & LLE_EXCLUSIVE) + LLE_WUNLOCK(lle); + else + LLE_RUNLOCK(lle); + return (NULL); + } return (lle); } Modified: stable/12/sys/netinet6/in6.c ============================================================================== --- stable/12/sys/netinet6/in6.c Fri Jan 25 20:20:27 2019 (r343453) +++ stable/12/sys/netinet6/in6.c Fri Jan 25 20:24:53 2019 (r343454) @@ -2315,16 +2315,13 @@ in6_lltable_lookup(struct lltable *llt, u_int flags, IF_AFDATA_LOCK_ASSERT(llt->llt_ifp); KASSERT(l3addr->sa_family == AF_INET6, ("sin_family %d", l3addr->sa_family)); + KASSERT((flags & (LLE_UNLOCKED | LLE_EXCLUSIVE)) != + (LLE_UNLOCKED | LLE_EXCLUSIVE), + ("wrong lle request flags: %#x", flags)); lle = in6_lltable_find_dst(llt, &sin6->sin6_addr); - if (lle == NULL) return (NULL); - - KASSERT((flags & (LLE_UNLOCKED|LLE_EXCLUSIVE)) != - (LLE_UNLOCKED|LLE_EXCLUSIVE),("wrong lle request flags: 0x%X", - flags)); - if (flags & LLE_UNLOCKED) return (lle); @@ -2332,6 +2329,18 @@ in6_lltable_lookup(struct lltable *llt, u_int flags, LLE_WLOCK(lle); else LLE_RLOCK(lle); + + /* + * If the afdata lock is not held, the LLE may have been unlinked while + * we were blocked on the LLE lock. Check for this case. + */ + if (__predict_false((lle->la_flags & LLE_LINKED) == 0)) { + if (flags & LLE_EXCLUSIVE) + LLE_WUNLOCK(lle); + else + LLE_RUNLOCK(lle); + return (NULL); + } return (lle); }