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	Fri, 26 Jul 2024 07:48:04 +0000
Date: Fri, 26 Jul 2024 08:48:04 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Michal Hocko <mhocko@suse.com>
Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] memcg_write_event_control(): fix a user-triggerable oops
Message-ID: <20240726074804.GE99483@ZenIV>
References: <20240726054357.GD99483@ZenIV>
 <ZqNLEc54NVP40Kpn@tiehlicka>
 <ZqNMfL6JmgHCJwBv@tiehlicka>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, Jul 26, 2024 at 09:13:00AM +0200, Michal Hocko wrote:
> On Fri 26-07-24 09:06:59, Michal Hocko wrote:
> > On Fri 26-07-24 06:43:57, Al Viro wrote:
> > > We are *not* guaranteed that anything past the terminating NUL
> > > is mapped (let alone initialized with anything sane).
> > >     
> > 
> > Fixes: 0dea116876ee ("cgroup: implement eventfd-based generic API for notifications")
> > 
> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> > 
> > Acked-by: Michal Hocko <mhocko@suse.com>
> 
> Btw. this should be
> Cc: stable

Point, except that for -stable it needs to be applied to mm/memcontrol.c
instead...