From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [PATCH 1/2] wimax: i2400m - prevent a possible kernel bug due to missing fw_name string Date: Mon, 26 Mar 2012 15:57:10 +0100 Message-ID: <1332773830.3500.88.camel@deadeye> References: <1332761036-8913-1-git-send-email-phil.sutter@viprinet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: David Miller , , To: Phil Sutter Return-path: Received: from mail.solarflare.com ([216.237.3.220]:31759 "EHLO ocex02.SolarFlarecom.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932444Ab2CZO5P (ORCPT ); Mon, 26 Mar 2012 10:57:15 -0400 In-Reply-To: <1332761036-8913-1-git-send-email-phil.sutter@viprinet.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 2012-03-26 at 13:23 +0200, Phil Sutter wrote: > This happened on a machine with a custom hotplug script calling nameif, > probably due to slow firmware loading. At the time nameif uses ethtool > to gather interface information, i2400m->fw_name is zero and so a null > pointer dereference occurs from within i2400m_get_drvinfo(). > > Signed-off-by: Phil Sutter > --- > drivers/net/wimax/i2400m/netdev.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/wimax/i2400m/netdev.c b/drivers/net/wimax/i2400m/netdev.c > index 64a1106..020bd8d 100644 > --- a/drivers/net/wimax/i2400m/netdev.c > +++ b/drivers/net/wimax/i2400m/netdev.c > @@ -607,7 +607,8 @@ static void i2400m_get_drvinfo(struct net_device *net_dev, > struct i2400m *i2400m = net_dev_to_i2400m(net_dev); > > strncpy(info->driver, KBUILD_MODNAME, sizeof(info->driver) - 1); > - strncpy(info->fw_version, i2400m->fw_name, sizeof(info->fw_version) - 1); > + strncpy(info->fw_version, > + i2400m->fw_name ? : "N/A", sizeof(info->fw_version) - 1); Use an empty string, not "N/A". Ben. > if (net_dev->dev.parent) > strncpy(info->bus_info, dev_name(net_dev->dev.parent), > sizeof(info->bus_info) - 1); -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.