[Ocfs2-devel] [PATCH v2] ocfs2: fix possible memory leak in dlm_process_recovery_data

[Sunil Mushran]

Do you know under what conditions does it create a new lock when it should
not?

This code should only trigger if the lockres is/was mastered on another
node.
Meaning this node will not know about the newlock. Meaning that code should
never trigger.

1949                         if (lock->ml.cookie == ml->cookie) {
This if looks hacky.

If you have a reproducible case, it may be worthwhile to get some traces to
see
under what conditions this happens. Should be straight forward after that.

Thanks
Sunil



On Thu, May 2, 2013 at 5:56 AM, Joseph Qi <joseph.qi at huawei.com> wrote:

>   We found a possible memory leak in dlm_process_recovery_data when doing
> code review. In dlm_process_recovery_data, it creates newlock each time,
> but don't free when it is bad, and then it will lead to memory leak.
>
> Cc: stable at vger.kernel.org
> Signed-off-by: Joseph Qi <joseph.qi at huawei.com> <joseph.qi at huawei.com>
> Reviewed-by: Jie Liu <jeff.liu at oracle.com> <jeff.liu at oracle.com>
>
> ---
>  fs/ocfs2/dlm/dlmrecovery.c |    4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
> index eeac97b..9f08523 100644
> --- a/fs/ocfs2/dlm/dlmrecovery.c
> +++ b/fs/ocfs2/dlm/dlmrecovery.c
> @@ -1974,6 +1974,10 @@ skip_lvb:
>  			     res->lockname.len, res->lockname.name, ml->node);
>  			dlm_lockres_set_refmap_bit(dlm, res, ml->node);
>  			added++;
> +		} else {
> +			/* Free the new lock if it is bad */
> +			dlm_lock_put(newlock);
> +			newlock = NULL;
>  		}
>  		spin_unlock(&res->spinlock);
>  	}
> --
> 1.7.9.7
>
>
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