[Ocfs2-devel] [PATCH 1/4] ocfs2: Fix freeing uninitialized resource on ocfs2_dlm_shutdown

[Joseph Qi]

On 7/30/22 9:14 AM, Heming Zhao wrote:
> On local mount mode, there is no dlm resource initalized. If
> ocfs2_mount_volume() fails in ocfs2_find_slot(), error handling
> flow will call ocfs2_dlm_shutdown(), then does dlm resource
> cleanup job, which will trigger kernel crash.
> 
> Fixes: 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job before
> return error")

Should be put at the same line.

> Signed-off-by: Heming Zhao <heming.zhao at suse.com>
> ---
>  fs/ocfs2/dlmglue.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
> index 801e60bab955..1438ac14940b 100644
> --- a/fs/ocfs2/dlmglue.c
> +++ b/fs/ocfs2/dlmglue.c
> @@ -3385,6 +3385,9 @@ int ocfs2_dlm_init(struct ocfs2_super *osb)
>  void ocfs2_dlm_shutdown(struct ocfs2_super *osb,
>  			int hangup_pending)
>  {
> +	if (ocfs2_mount_local(osb))
> +		return;
> +

IMO, we have to do part of ocfs2_dlm_shutdown() jobs such as
ocfs2_lock_res_free(), which will remove lockres from d_lockres_tracking
added by ocfs2_xxx_lock_res_init().

Before commit 0737e01de9c4, it seems this issue also exists since
osb->cconn is already set under local mount mode. 

Thanks,
Joseph