Re: [PATCH -mmotm 2/2] cpuset: alloc nodemask_t at heap not stack - fix

[David Rientjes <rientjes@google.com>]

On Fri, 12 Mar 2010, Miao Xie wrote:

> fix memory leak
> 
> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
> ---
> Against the following patch in mmotm-2010-03-11-13-13:
> cpuset-alloc-nodemask_t-at-heap-not-stack.patch
> ---
>  kernel/cpuset.c |   10 +++++++---
>  1 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/cpuset.c b/kernel/cpuset.c
> index f36e577..8e27d00 100644
> --- a/kernel/cpuset.c
> +++ b/kernel/cpuset.c
> @@ -1401,7 +1401,7 @@ static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont,
>  	NODEMASK_ALLOC(nodemask_t, to, GFP_KERNEL);
>  
>  	if (from == NULL || to == NULL)
> -		return;
> +		goto alloc_fail;
>  
>  	if (cs == &top_cpuset) {
>  		cpumask_copy(cpus_attach, cpu_possible_mask);
> @@ -1432,8 +1432,12 @@ static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont,
>  		mmput(mm);
>  	}
>  
> -	NODEMASK_FREE(from);
> -	NODEMASK_FREE(to);
> +alloc_fail:
> +	if (from)
> +		NODEMASK_FREE(from);
> +
> +	if (to)
> +		NODEMASK_FREE(to);

kfree() can take NULL pointers.