Commit 3e10a15f authored by Jeff Layton's avatar Jeff Layton Committed by Al Viro
Browse files

ceph: fix up error handling with snapdirs 



There are several warts in the snapdir error handling. The -EOPNOTSUPP
return in __snapfh_to_dentry is currently lost, and the call to
ceph_handle_snapdir is not currently checked at all.

Fix all of this up and eliminate a BUG_ON in ceph_get_snapdir. We can
handle that case with a warning and return an error.

Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 6e3e2c43

fs/ceph/dir.c

+2 −0
Original line number Diff line number Diff line
@@ -677,6 +677,8 @@ int ceph_handle_snapdir(struct ceph_mds_request *req, 
	    strcmp(dentry->d_name.name,

		   fsc->mount_options->snapdir_name) == 0) {

		struct inode *inode = ceph_get_snapdir(parent);

		if (IS_ERR(inode))

			return PTR_ERR(inode);

		dout("ENOENT on snapdir %p '%pd', linking to snapdir %p\n",

		     dentry, dentry, inode);

		BUG_ON(!d_unhashed(dentry));

fs/ceph/export.c

+5 −4
Original line number Diff line number Diff line
@@ -248,9 +248,10 @@ static struct dentry *__snapfh_to_dentry(struct super_block *sb, 
			ihold(inode);

		} else {

			/* mds does not support lookup snapped inode */

			err = -EOPNOTSUPP;

			inode = NULL;

			inode = ERR_PTR(-EOPNOTSUPP);

		}

	} else {

		inode = ERR_PTR(-ESTALE);

	}

	ceph_mdsc_put_request(req);
@@ -261,8 +262,8 @@ static struct dentry *__snapfh_to_dentry(struct super_block *sb, 
		dout("snapfh_to_dentry %llx.%llx parent %llx hash %x err=%d",

		      vino.ino, vino.snap, sfh->parent_ino, sfh->hash, err);

	}

	if (!inode)

		return ERR_PTR(-ESTALE);

	if (IS_ERR(inode))

		return ERR_CAST(inode);

	/* see comments in ceph_get_parent() */

	return unlinked ? d_obtain_root(inode) : d_obtain_alias(inode);

}

fs/ceph/inode.c

+13 −1
Original line number Diff line number Diff line
@@ -78,9 +78,21 @@ struct inode *ceph_get_snapdir(struct inode *parent) 
	struct inode *inode = ceph_get_inode(parent->i_sb, vino);

	struct ceph_inode_info *ci = ceph_inode(inode);



	BUG_ON(!S_ISDIR(parent->i_mode));

	if (IS_ERR(inode))

		return inode;



	if (!S_ISDIR(parent->i_mode)) {

		pr_warn_once("bad snapdir parent type (mode=0%o)\n",

			     parent->i_mode);

		return ERR_PTR(-ENOTDIR);

	}



	if (!(inode->i_state & I_NEW) && !S_ISDIR(inode->i_mode)) {

		pr_warn_once("bad snapdir inode type (mode=0%o)\n",

			     inode->i_mode);

		return ERR_PTR(-ENOTDIR);

	}



	inode->i_mode = parent->i_mode;

	inode->i_uid = parent->i_uid;

	inode->i_gid = parent->i_gid;