Btrfs: fix unprotected root node of the subvolume's inode rb-tree
The root node of the rb-tree may be changed, so we should get it under
the lock. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 790eceb..19eef3e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4843,14 +4843,13 @@
struct rb_node **p;
struct rb_node *parent;
u64 ino = btrfs_ino(inode);
-again:
- p = &root->inode_tree.rb_node;
- parent = NULL;
if (inode_unhashed(inode))
return;
-
+again:
+ parent = NULL;
spin_lock(&root->inode_lock);
+ p = &root->inode_tree.rb_node;
while (*p) {
parent = *p;
entry = rb_entry(parent, struct btrfs_inode, rb_node);