ceph: protect access to d_parent
d_parent is protected by d_lock: use it when looking up a dentry's parent
directory inode. Also take a reference and drop it in the caller to avoid
a use-after-free.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index c24891a..c1eb9a0 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -801,6 +801,7 @@
extern void ceph_dentry_lru_del(struct dentry *dn);
extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
extern unsigned ceph_dentry_hash(struct dentry *dn);
+extern struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry);
/*
* our d_ops vary depending on whether the inode is live,
@@ -823,14 +824,6 @@
int p_locks, int f_locks);
extern int lock_to_ceph_filelock(struct file_lock *fl, struct ceph_filelock *c);
-static inline struct inode *get_dentry_parent_inode(struct dentry *dentry)
-{
- if (dentry && dentry->d_parent)
- return dentry->d_parent->d_inode;
-
- return NULL;
-}
-
/* debugfs.c */
extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);