Re: [PATCH 09/12] Fix possible NULL pointer dereference in print_IO_APIC

[Jeremy Fitzhardinge <jeremy@goop.org>]

On 05/18/2010 03:23 AM, Stefano Stabellini wrote:
> Make sure chip_data is not NULL before accessing it.
>   

You should clarify under what circumstances it can be legitimately NULL.

    J

> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> ---
>  arch/x86/kernel/apic/io_apic.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> index eb2789c..c64499c 100644
> --- a/arch/x86/kernel/apic/io_apic.c
> +++ b/arch/x86/kernel/apic/io_apic.c
> @@ -1732,6 +1732,8 @@ __apicdebuginit(void) print_IO_APIC(void)
>  		struct irq_pin_list *entry;
>  
>  		cfg = desc->chip_data;
> +		if (!cfg)
> +			continue;
>  		entry = cfg->irq_2_pin;
>  		if (!entry)
>  			continue;
>