From 41883ba8ee91af979f4a02b5b0c78647ae82a80b Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 23 May 2019 10:22:55 +0800
Subject: ceph: use READ_ONCE to access d_parent in RCU critical section
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
fs/ceph/mds_client.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
(limited to 'fs/ceph')
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 0b78507eccb0..88bc68ddd313 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -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))
--
cgit