From: Amir Goldstein amir73il@gmail.com
commit 300b124fcf6ad2cd99a7b721e0f096785e0a3134 upstream.
Commit 6dde1e42f497 ("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: 6dde1e42f497 ("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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/overlayfs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -881,7 +881,7 @@ struct inode *ovl_get_inode(struct super 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; @@ -931,6 +931,8 @@ struct inode *ovl_get_inode(struct super 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);