[Ocfs2-devel] [PATCH] ocfs2: unlock rw lock if inode lock failed

[Andrew Morton]

On Mon, 6 May 2013 22:43:39 +0800 Joseph Qi <joseph.qi at huawei.com> wrote:

> In ocfs2_file_aio_write, it does ocfs2_rw_lock first and then
> ocfs2_inode_lock. But if ocfs2_inode_lock failed, it goes to out_sems
> without unlocking rw lock. This will cause a bug in ocfs2_lock_res_free
> when testing res->l_ex_holders, which is increased in
> __ocfs2_cluster_lock and decreased in __ocfs2_cluster_unlock.
> 
> ...
>
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -2290,7 +2290,7 @@ relock:
>  		ret = ocfs2_inode_lock(inode, NULL, 1);
>  		if (ret < 0) {
>  			mlog_errno(ret);
> -			goto out_sems;
> +			goto out;
>  		}
> 
>  		ocfs2_inode_unlock(inode, 1);

That seems like a fairly serious bug.  How long has it been there and
what userspace actions are required to trigger it?

(I'm trying to work out which kernel versions we should merge the
fix into, but the changelog didn't give me enough info to determine
this)