From mboxrd@z Thu Jan 1 00:00:00 1970 From: Micah Gruber Subject: [PATCH] Fix a potential NULL pointer dereference in uli526x_interrupt() in drivers/net/tulip/uli526x.c Date: Tue, 04 Sep 2007 16:06:50 +0800 Message-ID: <46DD121A.2010404@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, jgarzik@pobox.com Return-path: Received: from wx-out-0506.google.com ([66.249.82.225]:40362 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751309AbXIDIFn (ORCPT ); Tue, 4 Sep 2007 04:05:43 -0400 Received: by wx-out-0506.google.com with SMTP id h31so1736660wxd for ; Tue, 04 Sep 2007 01:05:42 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org This patch fixes a potential null dereference bug where we dereference dev before a null check. This patch simply moves the dereferencing after the null check. Signed-off-by: Micah Gruber --- --- a/drivers/net/tulip/uli526x.c +++ b/drivers/net/tulip/uli526x.c @@ -663,7 +663,7 @@ { struct net_device *dev = dev_id; struct uli526x_board_info *db = netdev_priv(dev); - unsigned long ioaddr; + unsigned long ioaddr = dev->base_addr; unsigned long flags; if (!dev) { @@ -671,8 +671,6 @@ return IRQ_NONE; } - ioaddr = dev->base_addr; - spin_lock_irqsave(&db->lock, flags); outl(0, ioaddr + DCR7);