From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20120527002521.928952544@linuxfoundation.org> Date: Sun, 27 May 2012 09:26:15 +0900 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Thomas Wucher , Thomas Gleixner , Felix Radensky , Kumar Gala , Grant Likely Subject: [ 69/91] gpio: mpc8xxx: Prevent NULL pointer deref in demux handler In-Reply-To: <20120527010903.GA18244@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner commit d6de85e85edcc38c9edcde45a0a568818fcddc13 upstream. commit cfadd838(powerpc/8xxx: Fix interrupt handling in MPC8xxx GPIO driver) added an unconditional call of chip->irq_eoi() to the demux handler. This leads to a NULL pointer derefernce on MPC512x platforms which use this driver as well. Make it conditional. Reported-by: Thomas Wucher Signed-off-by: Thomas Gleixner Cc: Felix Radensky Cc: Kumar Gala Cc: Grant Likely Signed-off-by: Grant Likely Signed-off-by: Greg Kroah-Hartman --- drivers/gpio/gpio-mpc8xxx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpio/gpio-mpc8xxx.c +++ b/drivers/gpio/gpio-mpc8xxx.c @@ -163,7 +163,8 @@ static void mpc8xxx_gpio_irq_cascade(uns if (mask) generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq, 32 - ffs(mask))); - chip->irq_eoi(&desc->irq_data); + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); } static void mpc8xxx_irq_unmask(struct irq_data *d)