linux-kernel - Re: [PATCH] net/ethoc: fix null dereference on error exit path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <57422295.4050007@canonical.com>
Date:	Sun, 22 May 2016 22:20:21 +0100
From:	Colin Ian King <colin.king@...onical.com>
To:	Max Filippov <jcmvbkbc@...il.com>
Cc:	"David S . Miller" <davem@...emloft.net>,
	Andrew Lunn <andrew@...n.ch>,
	Florian Fainelli <f.fainelli@...il.com>,
	Tobias Klauser <tklauser@...tanz.ch>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] net/ethoc: fix null dereference on error exit path

On 22/05/16 20:42, Max Filippov wrote:
> Hi Colin,
> 
> On Sun, May 22, 2016 at 08:08:18PM +0100, Colin King wrote:
>> From: Colin Ian King <colin.king@...onical.com>
>>
>> priv is assigned to NULL however all the error exit paths to label 'free'
>> dereference priv, causing a null pointer dereference.
>>
>> Examination of the code shows that all error exits via the 'free'
>> label path occur before priv is assigned to netdev_priv(netdev), hence
>> there is no need to call clk_disable_unprepare and so the location of
>> the label should be moved to free_netdev statement to avoid this null
>> dereference on priv.
> 
> This description is a bit inaccurate. Indeed all 'goto free' above the
> 'priv = netdev_priv(netdev);' need to skip 'if (priv->clk)' check, but
> there are two more 'goto free' below that line, and they look correct
> now, but after this patch they'll leave the clock enabled.
> 
Oops, I'll resend a corrected fix tomorrow