linux-kernel - Re: [PATCH] __bitmap_parselist: fix bug in empty string handling

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20FD3D67-54CF-45E6-81A9-273E25B8A154@ezchip.com>
Date:	Mon, 20 Apr 2015 23:50:19 +0000
From:	Chris Metcalf <cmetcalf@...hip.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
CC:	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Tejun Heo <tj@...nel.org>,
	"Peter Zijlstra (Intel)" <peterz@...radead.org>,
	Sudeep Holla <sudeep.holla@....com>,
	Michal Nazarewicz <mina86@...a86.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"stable@...r.kernel.org" <stable@...r.kernel.org>
Subject: Re: [PATCH] __bitmap_parselist: fix bug in empty string handling


> On Apr 20, 2015, at 1:17 PM, Andrew Morton <akpm@...ux-foundation.org> wrote:
> 
>> On Fri, 17 Apr 2015 14:00:04 -0400 Chris Metcalf <cmetcalf@...hip.com> wrote:
>> 
>> bitmap_parselist("", &mask, nmaskbits) will erroneously set bit
>> zero in the mask.  The same bug is visible in cpumask_parselist()
>> since it is layered on top of the bitmask code, e.g. if you boot with
>> "isolcpus=", you will actually end up with cpu zero isolated.
>> 
>> The bug was introduced in commit 4b060420a596 ("bitmap, irq: add
>> smp_affinity_list interface to /proc/irq") when bitmap_parselist()
>> was generalized to support userspace as well as kernelspace.
>> 
>> Signed-off-by: Chris Metcalf <cmetcalf@...hip.com>
>> Cc: stable@...r.kernel.org
> 
> I don't think we need to backport a fix for a 4 year old bug which has
> very minor consequences.  Am I wrong?

I don't have a strong feeling on this one. My guess is it's trivial to backport but also very low impact so either way is pretty reasonable.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/