From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754528AbZLBOeT (ORCPT ); Wed, 2 Dec 2009 09:34:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752986AbZLBOeS (ORCPT ); Wed, 2 Dec 2009 09:34:18 -0500 Received: from cantor.suse.de ([195.135.220.2]:34669 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752402AbZLBOeR (ORCPT ); Wed, 2 Dec 2009 09:34:17 -0500 Subject: Re: [PATCH][stable] b44 WOL setup: one-bit-off stack corruption kernel panic fix From: Stanislav Brabec To: Gary Zambrano Cc: Linux Kernel Mailing List , stable@kernel.org In-Reply-To: <1259761547.8709.264.camel@hammer.suse.cz> References: <1259761547.8709.264.camel@hammer.suse.cz> Content-Type: text/plain; charset="ISO-8859-2" Organization: SuSE CR, s. r. o. Date: Wed, 02 Dec 2009 15:35:20 +0100 Message-Id: <1259764520.8709.293.camel@hammer.suse.cz> Mime-Version: 1.0 X-Mailer: Evolution 2.28.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Stanislav Brabec wrote: > About 50% of shutdowns of b44 Ethernet adapter ends by kernel panic with > kernels compiled with stack-protector. > > Checking b44_magic_pattern() return values, one call of > b44_magic_pattern() returns 127. It means, that set_bit(128, pmask) was > called on line 1509. It means that bit 0 of 17th byte of pmask was > overwritten. But pmask has only 16 bytes. Stack corruption happens. > > It seems that set_bit() on line 1509 always writes one bit off. > > The fix does not only solve the stack corruption, but also makes Wake On > LAN working on my onboard B44 on Asus A7V-333X mainboard. > > It seems that this problem affects all kernel versions since commit > 725ad800 on 2006-06-20. stable@kernel.org may be interested as well. Adding Cc:. Signed-off-by: Stanislav Brabec Cc: stable@kernel.org diff --git a/drivers/net/b44.c b/drivers/net/b44.c index 2a91323..4869adb 100644 --- a/drivers/net/b44.c +++ b/drivers/net/b44.c @@ -1505,8 +1505,7 @@ static int b44_magic_pattern(u8 *macaddr, u8 *ppattern, u8 *pmask, int offset) for (k = 0; k< ethaddr_bytes; k++) { ppattern[offset + magicsync + (j * ETH_ALEN) + k] = macaddr[k]; - len++; - set_bit(len, (unsigned long *) pmask); + set_bit(len++, (unsigned long *) pmask); } } return len - 1; -- Best Regards / S pozdravem, Stanislav Brabec software developer --------------------------------------------------------------------- SUSE LINUX, s. r. o. e-mail: sbrabec@suse.cz Lihovarská 1060/12 tel: +420 284 028 966, +49 911 740538747 190 00 Praha 9 fax: +420 284 028 951 Czech Republic http://www.suse.cz/