Re: [patch 2/2] x86/mce/AMD: Make the init code more robust

From: Borislav Petkov
Date: Tue Dec 27 2016 - 02:07:34 EST


On Mon, Dec 26, 2016 at 10:58:20PM +0100, Thomas Gleixner wrote:
> If mce_device_init() fails then the mce device pointer is NULL and the AMD
> mce code happily dereferences it.
>
> Add a sanity check.
>
> Reported-by: Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx>
> Reported-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
> arch/x86/kernel/cpu/mcheck/mce_amd.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> @@ -1182,6 +1182,9 @@ static int threshold_create_bank(unsigne
> const char *name = get_name(bank, NULL);
> int err = 0;
>
> + if (!dev)
> + return -ENODEV;
> +
> if (is_shared_bank(bank)) {
> nb = node_to_amd_nb(amd_get_nb_id(cpu));

Acked-by: Borislav Petkov <bp@xxxxxxx>

>From looking at that code, though, it could use some more involved
straightening later.

/me puts it on TODO list.

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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