From owner-freebsd-pf@FreeBSD.ORG Mon Jun 4 10:30:19 2012 Return-Path: Delivered-To: freebsd-pf@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 18A2F1065673 for ; Mon, 4 Jun 2012 10:30:19 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 02C958FC17 for ; Mon, 4 Jun 2012 10:30:19 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.5/8.14.5) with ESMTP id q54AUIRo024480 for ; Mon, 4 Jun 2012 10:30:18 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.5/8.14.5/Submit) id q54AUIvC024477; Mon, 4 Jun 2012 10:30:18 GMT (envelope-from gnats) Date: Mon, 4 Jun 2012 10:30:18 GMT Message-Id: <201206041030.q54AUIvC024477@freefall.freebsd.org> To: freebsd-pf@FreeBSD.org From: Daniel Hartmeier Cc: Subject: Re: kern/168190: [pf] panic when using pf and route-to (maybe: bad fragment handling?) X-BeenThere: freebsd-pf@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Daniel Hartmeier List-Id: "Technical discussion and general questions about packet filter \(pf\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 04 Jun 2012 10:30:19 -0000 The following reply was made to PR kern/168190; it has been noted by GNATS. From: Daniel Hartmeier To: Joerg Pulz Cc: bug-followup@freebsd.org, freebsd-pf@freebsd.org Subject: Re: kern/168190: [pf] panic when using pf and route-to (maybe: bad fragment handling?) Date: Mon, 4 Jun 2012 12:25:44 +0200 Here's a patch that directly tests this theory. If correct, it will replace the panics with simple log messages that show when ipfilter left an m_len==0 mbuf. Daniel Index: sys/contrib/ipfilter/netinet/ip_fil_freebsd.c =================================================================== RCS file: /home/ncvs/src/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c,v retrieving revision 1.20.4.1 diff -u -r1.20.4.1 ip_fil_freebsd.c --- sys/contrib/ipfilter/netinet/ip_fil_freebsd.c 23 Sep 2011 00:51:37 -0000 1.20.4.1 +++ sys/contrib/ipfilter/netinet/ip_fil_freebsd.c 4 Jun 2012 10:19:04 -0000 @@ -182,8 +182,18 @@ static int fr_check_wrapper(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir) { + int r; + struct ip *ip = mtod(*mp, struct ip *); - return fr_check(ip, ip->ip_hl << 2, ifp, (dir == PFIL_OUT), mp); + ASSERT_HOST_BYTE_ORDER(*mp); + r = fr_check(ip, ip->ip_hl << 2, ifp, (dir == PFIL_OUT), mp); + if (*mp != NULL && (*mp)->m_pkthdr.len >= sizeof(struct ip) && + (*mp)->m_len < sizeof(struct ip)) { + printf("fr_check_wrapper: m_len %d fixed\n", + (int)(*mp)->m_len); + *mp = m_pullup(*mp, sizeof(struct ip)); + } + return r; } # ifdef USE_INET6