From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Thierry Reding <thierry.reding@gmail.com>
Cc: Shailendra Verma <shailendra.v@samsung.com>,
Laxman Dewangan <ldewangan@nvidia.com>,
Wolfram Sang <wsa@the-dreams.de>,
Stephen Warren <swarren@wwwdotorg.org>,
Alexandre Courbot <gnurou@gmail.com>,
linux-i2c@vger.kernel.org, linux-tegra@vger.kernel.org,
linux-kernel@vger.kernel.org, p.shailesh@samsung.com,
ashish.kalra@samsung.com,
Shailendra Verma <shailendra.capricorn@gmail.com>
Subject: Re: [PATCH] I2c: busses - Fix possible NULL derefrence.
Date: Mon, 30 Jan 2017 09:07:15 +0100 [thread overview]
Message-ID: <20170130080715.wuvx7ro3kuneolnu@pengutronix.de> (raw)
In-Reply-To: <20170130071217.GG3585@ulmo.ba.sec>
Hello,
On Mon, Jan 30, 2017 at 08:12:17AM +0100, Thierry Reding wrote:
> On Mon, Jan 30, 2017 at 10:33:07AM +0530, Shailendra Verma wrote:
> > of_device_get_match_data could return NULL, and so can cause
> > a NULL pointer dereference later.
> >
> > Signed-off-by: Shailendra Verma <shailendra.v@samsung.com>
> > ---
> > drivers/i2c/busses/i2c-tegra.c | 4 ++++
> > 1 file changed, 4 insertions(+)
>
> This will never happen. Any match in the OF table that would cause the
> ->probe() to occur has a valid .data pointer associated with it.
Theoretically you could (I think) bind that driver to a node with
compatible = "tegra-i2c";
Anyhow, even if today there was no possibility this could happen, that's
something that might easily be changed by a future change. So I doubt
"this will never happen" stays true for sure and being defensive is a
good idea. And even a BUG would be better than a silent NULL pointer
dereference.
Just my € 0.02
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
next prev parent reply other threads:[~2017-01-30 8:26 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20170130050324epcas3p28c9adcffd7bc40e1733cdeef1e5240d5@epcas3p2.samsung.com>
2017-01-30 5:03 ` [PATCH] I2c: busses - Fix possible NULL derefrence Shailendra Verma
2017-01-30 7:12 ` Thierry Reding
2017-01-30 8:07 ` Uwe Kleine-König [this message]
2017-01-30 8:54 ` Thierry Reding
2017-01-30 11:15 ` Uwe Kleine-König
2017-01-30 11:24 ` Thierry Reding
2017-02-09 16:37 ` Wolfram Sang
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