From: Kees Cook <kees@kernel.org>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: David Wang <00107082@163.com>,
brgl@bgdev.pl, tglx@linutronix.de, linux-kernel@vger.kernel.org,
linux-gpio@vger.kernel.org, geert@linux-m68k.org,
linux-hardening@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Rafael J. Wysocki" <rafael@kernel.org>
Subject: Re: [PATCH] Fix a potential abuse of seq_printf() format string in drivers
Date: Wed, 20 Nov 2024 10:12:40 -0800 [thread overview]
Message-ID: <202411201008.5262C14@keescook> (raw)
In-Reply-To: <CACRpkdZ0zwn0908LDqrfQJtF7M-WRcKA4qdJdwSXZNzm0L47CA@mail.gmail.com>
On Wed, Nov 20, 2024 at 08:35:38AM +0100, Linus Walleij wrote:
> On Wed, Nov 20, 2024 at 6:31 AM David Wang <00107082@163.com> wrote:
>
> > Using device name as format string of seq_printf() is proned to
> > "Format string attack", opens possibility for exploitation.
> > Seq_puts() is safer and more efficient.
> >
> > Signed-off-by: David Wang <00107082@163.com>
>
> Okay better get Kees' eye on this, he looks after string vulnerabilities.
> (But I think you're right.)
Agreed, this may lead to kernel memory content exposures. seq_puts()
looks right.
Reviewed-by: Kees Cook <kees@kernel.org>
To defend against this, it might be interesting to detect
single-argument seq_printf() usage and aim it at seq_puts()
automatically...
>
> > drivers/gpio/gpio-aspeed-sgpio.c | 2 +-
> > drivers/gpio/gpio-aspeed.c | 2 +-
> > drivers/gpio/gpio-ep93xx.c | 2 +-
> > drivers/gpio/gpio-hlwd.c | 2 +-
> > drivers/gpio/gpio-mlxbf2.c | 2 +-
> > drivers/gpio/gpio-omap.c | 2 +-
> > drivers/gpio/gpio-pca953x.c | 2 +-
> > drivers/gpio/gpio-pl061.c | 2 +-
> > drivers/gpio/gpio-tegra.c | 2 +-
> > drivers/gpio/gpio-tegra186.c | 2 +-
> > drivers/gpio/gpio-tqmx86.c | 2 +-
> > drivers/gpio/gpio-visconti.c | 2 +-
> > drivers/gpio/gpio-xgs-iproc.c | 2 +-
> > drivers/irqchip/irq-gic.c | 2 +-
> > drivers/irqchip/irq-mvebu-pic.c | 2 +-
> > drivers/irqchip/irq-versatile-fpga.c | 2 +-
> > drivers/pinctrl/bcm/pinctrl-iproc-gpio.c | 2 +-
> > drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 2 +-
> > drivers/pinctrl/pinctrl-mcp23s08.c | 2 +-
> > drivers/pinctrl/pinctrl-stmfx.c | 2 +-
> > drivers/pinctrl/pinctrl-sx150x.c | 2 +-
> > drivers/pinctrl/renesas/pinctrl-rzg2l.c | 2 +-
>
> Can you split this in three patches per-subsystem?
> One for gpio, one for irqchip and one for pinctrl?
>
> Then send to each subsystem maintainer and CC kees on
> each.
>
> I'm just the pinctrl maintainer. The rest can be found with
> scripts/get_maintainer.pl.
Oof. That's a lot of work for a mechanical change like this. Perhaps
Greg KH can take it directly to the drivers tree instead?
-Kees
--
Kees Cook
next prev parent reply other threads:[~2024-11-20 18:12 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-20 5:30 [PATCH] Fix a potential abuse of seq_printf() format string in drivers David Wang
2024-11-20 7:35 ` Linus Walleij
2024-11-20 9:00 ` David Wang
2024-11-20 18:12 ` Kees Cook [this message]
2024-11-20 19:28 ` Greg Kroah-Hartman
2024-11-22 4:38 ` Kees Cook
2024-11-22 14:35 ` Greg Kroah-Hartman
2024-11-22 19:54 ` Thomas Gleixner
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