[PATCH 5.19 127/158] ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown

Greg Kroah-Hartman
2022-08-29T11:33:24Z

From: Heming Zhao <ocfs2-devel@oss.oracle.com>

commit 550842cc60987b269e31b222283ade3e1b6c7fc8 upstream.

After commit 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job
before return error"), any procedure after ocfs2_dlm_init() fails will
trigger crash when calling ocfs2_dlm_shutdown().

ie: On local mount mode, no dlm resource is initialized. If
ocfs2_mount_volume() fails in ocfs2_find_slot(), error handling will call
ocfs2_dlm_shutdown(), then does dlm resource cleanup job, which will
trigger kernel crash.

This solution should bypass uninitialized resources in
ocfs2_dlm_shutdown().

Link: https://lkml.kernel.org/r/20220815085754.20417-1-heming.zhao@suse.com
Fixes: 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job before return error")
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ocfs2/dlmglue.c | 8 +++++---
fs/ocfs2/super.c | 3 +--
2 files changed, 6 insertions(+), 5 deletions(-)

--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -3403,10 +3403,12 @@ void ocfs2_dlm_shutdown(struct ocfs2_sup
ocfs2_lock_res_free(&osb->osb_nfs_sync_lockres);
ocfs2_lock_res_free(&osb->osb_orphan_scan.os_lockres);

- ocfs2_cluster_disconnect(osb->cconn, hangup_pending);
- osb->cconn = NULL;
+ if (osb->cconn) {
+ ocfs2_cluster_disconnect(osb->cconn, hangup_pending);
+ osb->cconn = NULL;

- ocfs2_dlm_shutdown_debug(osb);
+ ocfs2_dlm_shutdown_debug(osb);
+ }
}

static int ocfs2_drop_lock(struct ocfs2_super *osb,
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1914,8 +1914,7 @@ static void ocfs2_dismount_volume(struct
!ocfs2_is_hard_readonly(osb))
hangup_needed = 1;

- if (osb->cconn)
- ocfs2_dlm_shutdown(osb, hangup_needed);
+ ocfs2_dlm_shutdown(osb, hangup_needed);

ocfs2_blockcheck_stats_debugfs_remove(&osb->osb_ecc_stats);
debugfs_remove_recursive(osb->osb_debug_root);