Commit 300b124f authored Nov 19, 2019 by Amir Goldstein Committed by Miklos Szeredi Mar 17, 2020

ovl: fix value of i_ino for lower hardlink corner case



Commit 6dde1e42 ("ovl: make i_ino consistent with st_ino in more
cases"), relaxed the condition nfs_export=on in order to set the value of
i_ino to xino map of real ino.

Specifically, it also relaxed the pre-condition that index=on for
consistent i_ino. This opened the corner case of lower hardlink in
ovl_get_inode(), which calls ovl_fill_inode() with ino=0 and then
ovl_init_inode() is called to set i_ino to lower real ino without the xino
mapping.

Pass the correct values of ino;fsid in this case to ovl_fill_inode(), so it
can initialize i_ino correctly.

Fixes: 6dde1e42 ("ovl: make i_ino consistent with st_ino in more ...")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

parent fb33c651

fs/overlayfs/inode.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -891,7 +891,7 @@ struct inode ovl_get_inode(struct super_block sb,
		struct dentry *lowerdentry = lowerpath ? lowerpath->dentry : NULL;
		bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry,
		oip->index);
		int fsid = bylower ? oip->lowerpath->layer->fsid : 0;
		int fsid = bylower ? lowerpath->layer->fsid : 0;
		bool is_dir, metacopy = false;
		unsigned long ino = 0;
		int err = oip->newinode ? -EEXIST : -ENOMEM;
		@@ -941,6 +941,8 @@ struct inode ovl_get_inode(struct super_block sb,
		err = -ENOMEM;
		goto out_err;
		}
		ino = realinode->i_ino;
		fsid = lowerpath->layer->fsid;
		}
		ovl_fill_inode(inode, realinode->i_mode, realinode->i_rdev, ino, fsid);
		ovl_inode_init(inode, upperdentry, lowerdentry, oip->lowerdata);

Admin message