From owner-freebsd-current@freebsd.org Wed Aug 5 03:56:50 2015 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 27F959B3E29 for ; Wed, 5 Aug 2015 03:56:50 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Received: from gold.funkthat.com (gate2.funkthat.com [208.87.223.18]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "gold.funkthat.com", Issuer "gold.funkthat.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id DE95B6E1; Wed, 5 Aug 2015 03:56:49 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Received: from gold.funkthat.com (localhost [127.0.0.1]) by gold.funkthat.com (8.14.5/8.14.5) with ESMTP id t753ullA037644 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 4 Aug 2015 20:56:47 -0700 (PDT) (envelope-from jmg@gold.funkthat.com) Received: (from jmg@localhost) by gold.funkthat.com (8.14.5/8.14.5/Submit) id t753ulkv037643; Tue, 4 Aug 2015 20:56:47 -0700 (PDT) (envelope-from jmg) Date: Tue, 4 Aug 2015 20:56:47 -0700 From: John-Mark Gurney To: Ed Maste Cc: FreeBSD Current Subject: Re: Memory modified after free, seemingly geli related Message-ID: <20150805035646.GS78154@funkthat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: FreeBSD 9.1-PRERELEASE amd64 X-PGP-Fingerprint: 54BA 873B 6515 3F10 9E88 9322 9CB1 8F74 6D3F A396 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html X-TipJar: bitcoin:13Qmb6AeTgQecazTWph4XasEsP7nGRbAPE X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? User-Agent: Mutt/1.5.21 (2010-09-15) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (gold.funkthat.com [127.0.0.1]); Tue, 04 Aug 2015 20:56:48 -0700 (PDT) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Aug 2015 03:56:50 -0000 Ed Maste wrote this message on Wed, Aug 05, 2015 at 03:24 +0000: > I've encountered a few memory modified after free panics recently, > which seem to be from geli. I don't yet have any debugging to > completely confirm it's geli, but it has not happened on my other test > laptop which configured similarly but without geli. It is possible, but this doesn't tell us who last used the bio, just that when geli was allocating a bio, that the newly allocated bio was modified while it was free... It's likely that r284861 is just exposed a previously existing bug in the system... You could try to use memguard(9) to help catch the modification when it happens... > This has a few local patches from my to-commit-to-HEAD queue. > FreeBSD volta 11.0-CURRENT FreeBSD 11.0-CURRENT #10 > r284409+6a002d9(staging): Tue Jul 7 17:57:01 EDT 2015 > > panic: Memory modified after free 0xfffff80009d504d8(248) val=0 @ > 0xfffff80009d50518 > > cpuid = 1 > KDB: stack backtrace: > db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe011414a880 > vpanic() at vpanic+0x189/frame 0xfffffe011414a900 > panic() at panic+0x43/frame 0xfffffe011414a960 > trash_ctor() at trash_ctor+0x48/frame 0xfffffe011414a970 > uma_zalloc_arg() at uma_zalloc_arg+0x573/frame 0xfffffe011414a9e0 > g_clone_bio() at g_clone_bio+0x1d/frame 0xfffffe011414aa00 > g_eli_start() at g_eli_start+0xbd/frame 0xfffffe011414aa30 > g_io_schedule_down() at g_io_schedule_down+0xe6/frame 0xfffffe011414aa60 > g_down_procbody() at g_down_procbody+0x7d/frame 0xfffffe011414aa70 > fork_exit() at fork_exit+0x84/frame 0xfffffe011414aab0 > fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe011414aab0 > --- trap 0, rip = 0, rsp = 0xfffffe011414ab70, rbp = 0 --- > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."