ceph: ensure d_name stability in ceph_dentry_hash()

Take the d_lock here to ensure that d_name doesn't change.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Jeff Layton 2019-04-17 12:58:28 -04:00 committed by Ilya Dryomov
parent 1bcb344086
commit 76a495d666

View File

@ -1766,6 +1766,7 @@ static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
{
struct ceph_inode_info *dci = ceph_inode(dir);
unsigned hash;
switch (dci->i_dir_layout.dl_dir_hash) {
case 0: /* for backward compat */
@ -1773,8 +1774,11 @@ unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
return dn->d_name.hash;
default:
return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
spin_lock(&dn->d_lock);
hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
dn->d_name.name, dn->d_name.len);
spin_unlock(&dn->d_lock);
return hash;
}
}