From owner-freebsd-net@freebsd.org Wed Nov 28 09:10:46 2018 Return-Path: Delivered-To: freebsd-net@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 9FD97114D3EA for ; Wed, 28 Nov 2018 09:10:46 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 3487F6A2A5 for ; Wed, 28 Nov 2018 09:10:46 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id ECCE8114D3E0; Wed, 28 Nov 2018 09:10:45 +0000 (UTC) Delivered-To: net@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 CA836114D3DF for ; Wed, 28 Nov 2018 09:10:45 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.ysv.freebsd.org (mxrelay.ysv.freebsd.org [IPv6:2001:1900:2254:206a::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 69C016A29A for ; Wed, 28 Nov 2018 09:10:45 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.ysv.freebsd.org (Postfix) with ESMTPS id 9F3FD13F99 for ; Wed, 28 Nov 2018 09:10:44 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id wAS9AiE6054373 for ; Wed, 28 Nov 2018 09:10:44 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id wAS9AiQC054348 for net@FreeBSD.org; Wed, 28 Nov 2018 09:10:44 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 230498] Fatal trap 12: page fault while in kernel mode in sysctl_dumpentry from sysctl NET_RT_DUMP Date: Wed, 28 Nov 2018 09:10:41 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 11.2-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: ae@FreeBSD.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-Rspamd-Queue-Id: 3487F6A2A5 X-Spamd-Result: default: False [2.21 / 15.00]; local_wl_from(0.00)[freebsd.org]; NEURAL_SPAM_LONG(0.62)[0.618,0]; NEURAL_SPAM_MEDIUM(0.71)[0.707,0]; ASN(0.00)[asn:10310, ipnet:2001:1900:2254::/48, country:US]; NEURAL_SPAM_SHORT(0.88)[0.885,0] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Nov 2018 09:10:47 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D230498 --- Comment #21 from Andrey V. Elsukov --- (In reply to Franck Rousseau from comment #20) > (In reply to commit-hook from comment #19) >=20 > As mentioned in comment #9 above, this patch breaks ppp, I get this when > trying to re-open a second connection, this is the stage at which the cra= sh > occured before: > PPp ON localhost> Warning: iface add: ioctl(SIOCAIFADDR, 192.168.0.2 = -> > 192.168.0.1): File exists > Error: ipcp_InterfaceUp: unable to set ip address >=20 > Also, the patch in attachment #199450 [details] does not fix this specific > problem, we still crash the kernel with the procedure described earlier in > comment #12. As I said, I could narrow down the cause and find a fix for = our > use case, by using two different IPv4 addresses for Ethernet and PPP tun > interfaces the kernel does not crash anymore. >=20 > About the fix, I suspect that internal structures are corrupted, so any k= ind > of fix at this point will fail, for example with this patch on 11.2-p4 it > looks like I keep getting these values after the crash: >=20 > (kgdb) print rt->rt_ifp->if_flags > $3 =3D 3 > (kgdb) print rt->rt_ifp->if_index > $4 =3D 63488 >=20 > I will try to setup on-line debugging to watch internal structures and see > if I can get an idea of what is breaking things up. According to if_flags this patch doesn't affect your case, since if_flags = =3D (IFF_UP | IFF_BROADCAST). There is no IFF_DYING flag. Also, rtsock has seve= ral places where it can panic due to the similar issue, but with different stack trace (for example https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D205= 678). Are you sure that your panic is the same? Also if_index has unusual very la= rge value. Pleas, show your backtrace and show in context of noted frame the ou= tput of "p *rt->rt_ifp" command. --=20 You are receiving this mail because: You are the assignee for the bug.=