Re: [PATCH] mcheck: Correction to a missing return value frommisc_register

From: Andrew Morton
Date: Wed Mar 02 2011 - 19:06:25 EST


On Mon, 28 Feb 2011 12:19:04 +0100
Johan Wessfeldt <johan.wessfeldt@xxxxxxxxx> wrote:

> Return value from misc_register was not handled correctly
> in mcheck_init_device()
>
> Signed-off-by: Johan Wessfeldt <johan.wessfeldt@xxxxxxxxx>
> ---
> arch/x86/kernel/cpu/mcheck/mce.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
> index d916183..7274a11 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -2140,7 +2140,7 @@ static __init int mcheck_init_device(void)
> }
>
> register_hotcpu_notifier(&mce_cpu_notifier);
> - misc_register(&mce_log_device);
> + err = misc_register(&mce_log_device);
>
> return err;
> }

It should be fixed, but not that way. If misc_register() fails here,
mcheck_init_device() should undo all the things which it just did.

And the memory leak which occurs if sysdev_class_register() fails and
the memory and other resource leaks which occur if mce_create_device()
fails should be fixed too.

mcheck_init_device() a rather optimistic function.
--
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/