ocfs2: Check the owner of a lockres inside the spinlock
The checking of lockres owner in dlm_update_lvb() is not inside spinlock
protection. I don't see problem in current call path of dlm_update_lvb().
But just for code robustness.
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
diff --git a/fs/ocfs2/dlm/dlmast.c b/fs/ocfs2/dlm/dlmast.c
index dccc439..b7a25ef 100644
--- a/fs/ocfs2/dlm/dlmast.c
+++ b/fs/ocfs2/dlm/dlmast.c
@@ -185,9 +185,8 @@
BUG_ON(!lksb);
/* only updates if this node masters the lockres */
+ spin_lock(&res->spinlock);
if (res->owner == dlm->node_num) {
-
- spin_lock(&res->spinlock);
/* check the lksb flags for the direction */
if (lksb->flags & DLM_LKSB_GET_LVB) {
mlog(0, "getting lvb from lockres for %s node\n",
@@ -202,8 +201,8 @@
* here. In the future we might want to clear it at the time
* the put is actually done.
*/
- spin_unlock(&res->spinlock);
}
+ spin_unlock(&res->spinlock);
/* reset any lvb flags on the lksb */
lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB);