From owner-freebsd-bugs@FreeBSD.ORG Tue May 15 18:10:16 2007 Return-Path: X-Original-To: freebsd-bugs@hub.freebsd.org Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7CB7416A400 for ; Tue, 15 May 2007 18:10:16 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [69.147.83.40]) by mx1.freebsd.org (Postfix) with ESMTP id 34E5A13C455 for ; Tue, 15 May 2007 18:10:16 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.13.4/8.13.4) with ESMTP id l4FIAFOi041337 for ; Tue, 15 May 2007 18:10:15 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.13.4/8.13.4/Submit) id l4FIAF0O041336; Tue, 15 May 2007 18:10:15 GMT (envelope-from gnats) Date: Tue, 15 May 2007 18:10:15 GMT Message-Id: <200705151810.l4FIAF0O041336@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Remko Lodder Cc: Subject: Re: kern/112670: [if_tap] stat /dev/tapN leads to panic for N >= 2G X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Remko Lodder List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 May 2007 18:10:16 -0000 The following reply was made to PR kern/112670; it has been noted by GNATS. From: Remko Lodder To: Ludovico Gardenghi Cc: freebsd-gnats-submit@FreeBSD.org Subject: Re: kern/112670: [if_tap] stat /dev/tapN leads to panic for N >= 2G Date: Tue, 15 May 2007 20:08:05 +0200 Ludovico Gardenghi wrote: >> Number: 112670 >> Category: kern >> Synopsis: [if_tap] stat /dev/tapN leads to panic for N >= 2G >> Confidential: no >> Severity: serious >> Priority: medium >> Responsible: freebsd-bugs >> State: open >> Quarter: >> Keywords: >> Date-Required: >> Class: sw-bug >> Submitter-Id: current-users >> Arrival-Date: Mon May 14 23:00:11 GMT 2007 >> Closed-Date: >> Last-Modified: >> Originator: Ludovico Gardenghi >> Release: 6.2-RELEASE >> Organization: > Virtual Square Team >> Environment: > FreeBSD devil.localdomain 6.2-RELEASE FreeBSD 6.2-RELEASE #0: Fri Jan 12 10:40:27 UTC 2007 root@dessler.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC i386 >> Description: > Trying to access a tap device in /dev leads to a kernel panic ("foo") if the tap name is tapN when N is greater or equal than 2^31 and less than 2^32-1. > > This is probably due to a bad conversion between unsigned and signed in dev_stdclone (kern_conf.c:750). The tap name is converted from string to integer with a loop (lines 762--765) and stored in the signed int variable 'u'; if the resulting value is greater than 2G, u becomes negative and the check at line 766 (if (u > 0xffffff)) fails, but the original value is in fact greater than that value and should be rejected. >> How-To-Repeat: > shammash@devil:~$ ls -l /dev/tap2147483648 > > (the following is in /var/log/messages) > > May 10 13:57:12 devil kernel: dev 0xc370a000 (tap-1530494977) is on clonelist > May 10 13:57:12 devil kernel: unit=-1530494977, low=0, extra=0x0 > May 10 13:57:12 devil kernel: 0xc36b4b00 tap0 > May 10 13:57:12 devil kernel: 0xc36f1500 tap255 > May 10 13:57:12 devil kernel: 0xc34f2000 tap256 > May 10 13:57:12 devil kernel: 0xc32aee00 tap65537 > May 10 13:57:12 devil kernel: 0xc36f1a00 tap1 > May 10 13:57:12 devil kernel: 0xc36f1600 tap2 > May 10 13:57:12 devil kernel: 0xc370a000 tap-1530494977 > May 10 13:57:12 devil kernel: panic: foo > May 10 13:57:12 devil kernel: Uptime: 35m24s > May 10 13:57:12 devil kernel: Cannot dump. No dump device defined. > May 10 13:57:12 devil kernel: Automatic reboot in 15 seconds - press a key on the console to abort > May 10 13:57:12 devil kernel: Rebooting... >> Fix: > It should be enough to change 'int' to 'unsigned int' inside the functions involved in tap creation, mainly dev_stdclone() in kern/kern_conf.c. >> Release-Note: >> Audit-Trail: >> Unformatted: > _______________________________________________ > freebsd-bugs@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-bugs > To unsubscribe, send any mail to "freebsd-bugs-unsubscribe@freebsd.org" Can you try obtaining us a kernel dump as mentioned in the developers handbook? Thanks! -- Kind regards, Remko Lodder ** remko@elvandar.org FreeBSD ** remko@FreeBSD.org /* Quis custodiet ipsos custodes */