From: Konstantin Khlebnikov <koct9i@gmail.com>
Date: Sun, 31 Jan 2016 13:21:29 +0000 (+0300)
Subject: ovl: copy new uid/gid into overlayfs runtime inode
X-Git-Tag: v4.1.21~30
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=546a8b3c4059af5fd8466f3d1848321e7613904c;p=thirdparty%2Fkernel%2Fstable.git

ovl: copy new uid/gid into overlayfs runtime inode

[ Upstream commit b81de061fa59f17d2730aabb1b84419ef3913810 ]

Overlayfs must update uid/gid after chown, otherwise functions
like inode_owner_or_capable() will check user against stale uid.
Catched by xfstests generic/087, it chowns file and calls utimes.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index a1b069e5e363e..e505b44a91848 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -66,6 +66,8 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
 	if (upperdentry) {
 		mutex_lock(&upperdentry->d_inode->i_mutex);
 		err = notify_change(upperdentry, attr, NULL);
+		if (!err)
+			ovl_copyattr(upperdentry->d_inode, dentry->d_inode);
 		mutex_unlock(&upperdentry->d_inode->i_mutex);
 	} else {
 		err = ovl_copy_up_last(dentry, attr, false);