Commit 41883ba8 authored by Yan, Zheng's avatar Yan, Zheng Committed by Ilya Dryomov
Browse files

ceph: use READ_ONCE to access d_parent in RCU critical section 



Signed-off-by: default avatar"Yan, Zheng" <zyan@redhat.com>
Reviewed-by: default avatarJeff Layton <jlayton@redhat.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent feab6ac2

fs/ceph/mds_client.c

+2 −2
Original line number Diff line number Diff line
@@ -913,7 +913,7 @@ static int __choose_mds(struct ceph_mds_client *mdsc, 
		struct inode *dir;



		rcu_read_lock();

		parent = req->r_dentry->d_parent;

		parent = READ_ONCE(req->r_dentry->d_parent);

		dir = req->r_parent ? : d_inode_rcu(parent);



		if (!dir || dir->i_sb != mdsc->fsc->sb) {
@@ -2145,7 +2145,7 @@ retry: 
			memcpy(path + pos, temp->d_name.name, temp->d_name.len);

		}

		spin_unlock(&temp->d_lock);

		temp = temp->d_parent;

		temp = READ_ONCE(temp->d_parent);



		/* Are we at the root? */

		if (IS_ROOT(temp))