[PATCH 1/1] omap: Ptr "isr_reg" tracked as NULL was dereferenced

From: Evgeny Kuznetsov
Date: Tue Oct 05 2010 - 04:46:39 EST


From: Evgeny Kuznetsov <ext-eugeny.kuznetsov@xxxxxxxxx>

Value of "isr_reg" pointer is depend on configuration and GPIO method.
Potentially it may have NULL value and it is dereferenced later
in code. If pointer is NULL there is some kernel bug.
Log line and 'BUG' macro are added to halt code execution in this case.

Signed-off-by: Evgeny Kuznetsov <EXT-Eugeny.Kuznetsov@xxxxxxxxx>
---
arch/arm/plat-omap/gpio.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index c05c653..7669928 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -1318,6 +1318,13 @@ static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
if (bank->method == METHOD_GPIO_44XX)
isr_reg = bank->base + OMAP4_GPIO_IRQSTATUS0;
#endif
+
+ if (!isr_reg) {
+ printk(KERN_ERR "FATAL: Incorrect GPIO method %i\n",
+ bank->method);
+ BUG();
+ }
+
while(1) {
u32 isr_saved, level_mask = 0;
u32 enabled;
--
1.6.3.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/