[PATCH v2] ocfs2: Fix a use after free on error

[Dan Carpenter]

The error handling in this function frees "reg" but it is still on the
"o2hb_all_regions" list so it will lead to a use after freew.  Joseph Qi
points out that we need to clear the bit in the "o2hb_region_bitmap" as
well

Fixes: 1cf257f51191 ("ocfs2: fix memory leak")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
v2: The first version didn't clear the bit.

 fs/ocfs2/cluster/heartbeat.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 0179a73a3fa2..12a7590601dd 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -2042,7 +2042,7 @@ static struct config_item 
*o2hb_heartbeat_group_make_item(struct config_group *g
                        o2hb_nego_timeout_handler,
                        reg, NULL, &reg->hr_handler_list);
        if (ret)
-               goto free;
+               goto remove_item;
 
        ret = o2net_register_handler(O2HB_NEGO_APPROVE_MSG, reg->hr_key,
                        sizeof(struct o2hb_nego_msg),
@@ -2057,6 +2057,12 @@ static struct config_item 
*o2hb_heartbeat_group_make_item(struct config_group *g
 
 unregister_handler:
        o2net_unregister_handler_list(&reg->hr_handler_list);
+remove_item:
+       spin_lock(&o2hb_live_lock);
+       list_del(&reg->hr_all_item);
+       if (o2hb_global_heartbeat_active())
+               clear_bit(reg->hr_region_num, o2hb_region_bitmap);
+       spin_unlock(&o2hb_live_lock);
 free:
        kfree(reg);
        return ERR_PTR(ret);
-- 
2.30.0