[PATCH] x86: mce: Potential memory leaks when initializing mcheck devices

[PATCH] x86: mce: Potential memory leaks when initializing mcheck devices

[Johan Wessfeldt]

This patch makes sure cleanup is done properly when mcheck fails
initializing any of its resources.

Note!
It should be safe to call mce_remove_device on ANY of the cpus as
mce_remove_device checks if corresponding cpu was initialized
before removing its resources.

Please review.

Signed-off-by: Johan Wessfeldt <johan.wessfeldt@gmail.com>
---
 arch/x86/kernel/cpu/mcheck/mce.c |   17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index d916183..273f2f6 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -2136,15 +2136,26 @@ static __init int mcheck_init_device(void)
 	for_each_online_cpu(i) {
 		err = mce_create_device(i);
 		if (err)
-			return err;
+			goto out_unreg;
 	}
 
 	register_hotcpu_notifier(&mce_cpu_notifier);
-	misc_register(&mce_log_device);
+	err = misc_register(&mce_log_device);
+	if (err)
+		goto out_unreg_hotcpu;
+
+	return 0;
+
+out_unreg_hotcpu:
+	unregister_hotcpu_notifier(&mce_cpu_notifier);
+out_unreg:
+	for_each_online_cpu(i)
+		mce_remove_device(i);
 
+	sysdev_class_unregister(&mce_sysclass);
+	free_cpumask_var(mce_dev_initialized);
 	return err;
 }
-
 device_initcall(mcheck_init_device);
 
 /*
-- 
1.7.2.3

Re: [PATCH] x86: mce: Potential memory leaks when initializing mcheck devices

[Johan Wessfeldt]

Oops
missed another call to free_cpumask_var().  Will send a v2 patch

Regards
// Johan W

On Fri, Mar 4, 2011 at 7:31 PM, Johan Wessfeldt
<johan.wessfeldt@gmail.com> wrote:
> This patch makes sure cleanup is done properly when mcheck fails
> initializing any of its resources.
>
> Note!
> It should be safe to call mce_remove_device on ANY of the cpus as
> mce_remove_device checks if corresponding cpu was initialized
> before removing its resources.
>
> Please review.
>
> Signed-off-by: Johan Wessfeldt <johan.wessfeldt@gmail.com>
> ---
>  arch/x86/kernel/cpu/mcheck/mce.c |   17 ++++++++++++++---
>  1 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
> index d916183..273f2f6 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -2136,15 +2136,26 @@ static __init int mcheck_init_device(void)
>        for_each_online_cpu(i) {
>                err = mce_create_device(i);
>                if (err)
> -                       return err;
> +                       goto out_unreg;
>        }
>
>        register_hotcpu_notifier(&mce_cpu_notifier);
> -       misc_register(&mce_log_device);
> +       err = misc_register(&mce_log_device);
> +       if (err)
> +               goto out_unreg_hotcpu;
> +
> +       return 0;
> +
> +out_unreg_hotcpu:
> +       unregister_hotcpu_notifier(&mce_cpu_notifier);
> +out_unreg:
> +       for_each_online_cpu(i)
> +               mce_remove_device(i);
>
> +       sysdev_class_unregister(&mce_sysclass);
> +       free_cpumask_var(mce_dev_initialized);
>        return err;
>  }
> -
>  device_initcall(mcheck_init_device);
>
>  /*
> --
> 1.7.2.3
>
>

[PATCH V2] x86: mce: Potential memory leaks when initializing mcheck devices

[Johan Wessfeldt]

This patch makes sure cleanup is done properly when mcheck fails
initializing any of its resources.

Signed-off-by: Johan Wessfeldt <johan.wessfeldt@gmail.com>
---
v2: call free_cpumask_var() if sysdev_class_register() fails

 arch/x86/kernel/cpu/mcheck/mce.c |   20 ++++++++++++++++----
 1 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index d916183..3cbd5a0 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -2131,20 +2131,32 @@ static __init int mcheck_init_device(void)
 
 	err = sysdev_class_register(&mce_sysclass);
 	if (err)
-		return err;
+		goto out_free;
 
 	for_each_online_cpu(i) {
 		err = mce_create_device(i);
 		if (err)
-			return err;
+			goto out_unreg;
 	}
 
 	register_hotcpu_notifier(&mce_cpu_notifier);
-	misc_register(&mce_log_device);
+	err = misc_register(&mce_log_device);
+	if (err)
+		goto out_unreg_hotcpu;
 
+	return 0;
+
+out_unreg_hotcpu:
+	unregister_hotcpu_notifier(&mce_cpu_notifier);
+out_unreg:
+	for_each_online_cpu(i)
+		mce_remove_device(i);
+
+	sysdev_class_unregister(&mce_sysclass);
+out_free:
+	free_cpumask_var(mce_dev_initialized);
 	return err;
 }
-
 device_initcall(mcheck_init_device);
 
 /*
-- 
1.7.2.3