From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH] sched/core: check format and overflows in cgroup2 cpu.max
Date: Tue, 5 Mar 2019 07:57:41 -0800
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To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org, Ingo Molnar <mingo@redhat.com>

Hello,

On Wed, Feb 27, 2019 at 11:13:21AM +0300, Konstantin Khlebnikov wrote:
> Cgroup2 interface for cpu bandwidth limit has some flaws:
> 
> - on stack buffer overflow
> - no checks for valid format or trailing garbage
> - no checks for integer overflows
> 
> This patch fixes all these flaws.

Ditto as the blkio patch.  Unless there is a correctness problem, my
preference is towards keeping the parsing functions simple and I don't
think the kernel needs to play the role of strict input verifier here
as long as the only foot getting shot is the user's own.

Thanks.

-- 
tejun