From: Amir Goldstein <amir73il@gmail.com>
Date: Wed, 15 Jul 2020 13:38:08 +0000 (+0300)
Subject: ovl: fix lookup of indexed hardlinks with metacopy
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4518dfcf761e3c44632855abcf433236cf7ab6c6;p=linux.git

ovl: fix lookup of indexed hardlinks with metacopy

We recently moved setting inode flag OVL_UPPERDATA to ovl_lookup().

When looking up an overlay dentry, upperdentry may be found by index
and not by name.  In that case, we fail to read the metacopy xattr
and falsly set the OVL_UPPERDATA on the overlay inode.

This caused a regression in xfstest overlay/033 when run with
OVERLAY_MOUNT_OPTIONS="-o metacopy=on".

Fixes: 28166ab3c875 ("ovl: initialize OVL_UPPERDATA in ovl_lookup()")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 3cad68c3efb25..f7d4358db6378 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -1066,6 +1066,10 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 			upperredirect = NULL;
 			goto out_free_oe;
 		}
+		err = ovl_check_metacopy_xattr(upperdentry);
+		if (err < 0)
+			goto out_free_oe;
+		uppermetacopy = err;
 	}
 
 	if (upperdentry || ctr) {