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[109.81.83.231]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5ac63590ac3sm1578410a12.34.2024.07.26.00.54.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Jul 2024 00:54:33 -0700 (PDT) Date: Fri, 26 Jul 2024 09:54:32 +0200 From: Michal Hocko To: Al Viro Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] memcg_write_event_control(): fix a user-triggerable oops Message-ID: References: <20240726054357.GD99483@ZenIV> <20240726074804.GE99483@ZenIV> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240726074804.GE99483@ZenIV> On Fri 26-07-24 08:48:04, Al Viro wrote: > 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 > > > > > > Acked-by: Michal Hocko > > > > Btw. this should be > > Cc: stable > > Point, except that for -stable it needs to be applied to mm/memcontrol.c > instead... Correct. And if anybody wants to backport to pre 3.14 then to kernel/cgroup.c -- Michal Hocko SUSE Labs