From owner-freebsd-net@freebsd.org Thu Jan 24 22:31:42 2019 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 3948314C12CF for ; Thu, 24 Jan 2019 22:31:42 +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 C6C138AA7E for ; Thu, 24 Jan 2019 22:31:41 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id 843F914C12CD; Thu, 24 Jan 2019 22:31:41 +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 72D0714C12CC for ; Thu, 24 Jan 2019 22:31:41 +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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 118B98AA74 for ; Thu, 24 Jan 2019 22:31:41 +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 590F414E12 for ; Thu, 24 Jan 2019 22:31:40 +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 x0OMVevG002457 for ; Thu, 24 Jan 2019 22:31:40 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id x0OMVeB3002456 for net@FreeBSD.org; Thu, 24 Jan 2019 22:31:40 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 235097] ci runs panic with use-after-free when running sys/netpfil/pf/nat tests Date: Thu, 24 Jan 2019 22:31:40 +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: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: kp@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-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: Thu, 24 Jan 2019 22:31:42 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D235097 --- Comment #11 from Kristof Provost --- I think I understand the use-after-free bug, and it's a pf problem. Patching the counter increment code to check for 0xdeadc0dedeadc0de (and panicing) produces this backtrace: panic: Incrementing freed counter! cpuid =3D 0 time =3D 1548368229 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe00a94da= 210 vpanic() at vpanic+0x1b4/frame 0xfffffe00a94da270 panic() at panic+0x43/frame 0xfffffe00a94da2d0 pf_purge_expired_src_nodes() at pf_purge_expired_src_nodes+0x1f4/frame 0xfffffe00a94da320 pf_unload_vnet_purge() at pf_unload_vnet_purge+0x2b/frame 0xfffffe00a94da330 vnet_pf_uninit() at vnet_pf_uninit+0x74a/frame 0xfffffe00a94da7d0 vnet_destroy() at vnet_destroy+0x124/frame 0xfffffe00a94da800 prison_deref() at prison_deref+0x29d/frame 0xfffffe00a94da840 sys_jail_remove() at sys_jail_remove+0x28e/frame 0xfffffe00a94da890 amd64_syscall() at amd64_syscall+0x29b/frame 0xfffffe00a94da9b0 fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe00a94da9b0 Essentially, pf frees its counters before it's all the way done cleaning up, and it can end up incrementing a counter. --=20 You are receiving this mail because: You are the assignee for the bug.=