linux-kernel - Re: [PATCH] Input: eeti_ts: Mark as CONFIG

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120410101047.GQ24211@n2100.arm.linux.org.uk>
Date:	Tue, 10 Apr 2012 11:10:47 +0100
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	Olof Johansson <olof@...om.net>
Cc:	Sven Neumann <s.neumann@...mfeld.com>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Haojian Zhuang <haojian.zhuang@...vell.com>,
	linux-kernel@...r.kernel.org, Daniel Mack <daniel@...aq.de>,
	linux-input@...r.kernel.org, Daniel Mack <zonque@...il.com>,
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] Input: eeti_ts: Mark as CONFIG_BROKEN

On Sat, Apr 07, 2012 at 01:32:31PM -0700, Olof Johansson wrote:
> Haojian, I think it was probably premature to do the multiplatform
> change like that, since it means that a PXA-only kernel has no mapping
> from irq_to_gpio to pxa_irq_to_gpio. Can you please address this as a
> fix for 3.4?

Please fix ezx-pcap instead - it's broken as it currently stands by using
irq_to_gpio(), and it's one reason why my randconfig builds on OMAP fail.

The big problem is - what does this do:

        do {
...
        } while (gpio_get_value(irq_to_gpio(pcap->spi->irq)));

if pcap->spi->irq has no GPIO associated with the interrupt?  irq_to_gpio()
probably returns some random number which might be some other GPIO in the
system, and gpio_get_value() could oops if irq_to_gpio returns a negative
or large positive number.  To put it another way, according to the above
code, irq_to_gpio() must always return a valid gpio for the IRQ even if
the IRQ doesn't have a GPIO associated with it.

This is a fine illustration of why irq_to_gpio() is just plain broken in
its design.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/