[PATCH 1/1] arm/mach-vexpress: array accessed out of bounds

[Nicolas Pitre]

On Sun, 13 Apr 2014, xypron.glpk at gmx.de wrote:

> From: Heinrich Schuchardt <xypron.glpk at gmx.de>
> 
> dcscb_allcpus_mask is an array of size 2.
> 
> The index variable cluster has to be checked against this limit
> before accessing the array.
> 
> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>

Acked-by: Nicolas Pitre <nico at linaro.org>

Please send it to the ARM-SOC team.


> ---
>  arch/arm/mach-vexpress/dcscb.c |    7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mach-vexpress/dcscb.c b/arch/arm/mach-vexpress/dcscb.c
> index 14d4996..5cbf7fa 100644
> --- a/arch/arm/mach-vexpress/dcscb.c
> +++ b/arch/arm/mach-vexpress/dcscb.c
> @@ -51,12 +51,14 @@ static int dcscb_allcpus_mask[2];
>  static int dcscb_power_up(unsigned int cpu, unsigned int cluster)
>  {
>  	unsigned int rst_hold, cpumask = (1 << cpu);
> -	unsigned int all_mask = dcscb_allcpus_mask[cluster];
> +	unsigned int all_mask;
>  
>  	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
>  	if (cpu >= 4 || cluster >= 2)
>  		return -EINVAL;
>  
> +	all_mask = dcscb_allcpus_mask[cluster];
> +
>  	/*
>  	 * Since this is called with IRQs enabled, and no arch_spin_lock_irq
>  	 * variant exists, we need to disable IRQs manually here.
> @@ -101,11 +103,12 @@ static void dcscb_power_down(void)
>  	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
>  	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
>  	cpumask = (1 << cpu);
> -	all_mask = dcscb_allcpus_mask[cluster];
>  
>  	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
>  	BUG_ON(cpu >= 4 || cluster >= 2);
>  
> +	all_mask = dcscb_allcpus_mask[cluster];
> +
>  	__mcpm_cpu_going_down(cpu, cluster);
>  
>  	arch_spin_lock(&dcscb_lock);
> -- 
> 1.7.10.4
>