From: Simon Horman <horms@kernel.org>
To: Gui-Dong Han <2045gemini@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>,
3chas3@gmail.com, linux-atm-general@lists.sourceforge.net,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
baijiaju1990@gmail.com, stable@vger.kernel.org
Subject: Re: [PATCH] atm/fore200e: Fix possible data race in fore200e_open()
Date: Mon, 20 Jan 2025 10:55:55 +0000 [thread overview]
Message-ID: <20250120105555.GV6206@kernel.org> (raw)
In-Reply-To: <CAOPYjvaVZAHqWhzYsLjtc4Q8CSCF2g4bG-efLHPOP_NMSs0crg@mail.gmail.com>
On Fri, Jan 17, 2025 at 10:28:59AM +0800, Gui-Dong Han wrote:
> > On Wed, 15 Jan 2025 13:10:06 +0000 Gui-Dong Han wrote:
> > > Protect access to fore200e->available_cell_rate with rate_mtx lock to
> > > prevent potential data race.
> > >
> > > The field fore200e.available_cell_rate is generally protected by the lock
> > > fore200e.rate_mtx when accessed. In all other read and write cases, this
> > > field is consistently protected by the lock, except for this case and
> > > during initialization.
> >
> > That's not sufficient in terms of analysis.
> >
> > You need to be able to articulate what can go wrong.
>
> fore200e->available_cell_rate += vcc->qos.txtp.max_pcr;
> In this case, since the update depends on a prior read, a data race
> could lead to a wrong fore200e.available_cell_rate value.
Hi Gui-Dong Han,
I think it would be good to post a v2 of this patch with
an explanation along the lines of the above included in
the patch description.
next prev parent reply other threads:[~2025-01-20 10:55 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-15 13:10 [PATCH] atm/fore200e: Fix possible data race in fore200e_open() Gui-Dong Han
2025-01-17 0:59 ` Jakub Kicinski
2025-01-17 2:28 ` Gui-Dong Han
2025-01-20 10:55 ` Simon Horman [this message]
2025-01-22 2:48 ` Gui-Dong Han
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