[PATCH] ocfs2/dlm: Fixes oops in dlm_new_lockres()

Patch fixes a race that can result in an oops while adding a
lockres to the dlm lockres tracking list.

Bug introduced by mainline commit 29576f8bb54045be944ba809d4fca1ad77c94165.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index efc015c6128a..44f87caf3683 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -606,7 +606,9 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 
         res->last_used = 0;
 
+        spin_lock(&dlm->spinlock);
         list_add_tail(&res->tracking, &dlm->tracking_list);
+        spin_unlock(&dlm->spinlock);
 
         memset(res->lvb, 0, DLM_LVB_LEN);
         memset(res->refmap, 0, sizeof(res->refmap));