linux-kernel - [PATCH 4.2.y-ckt 67/98] ovl: copy new uid/gid into overlayfs runtime inode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1458084692-23100-68-git-send-email-kamal@canonical.com>
Date:	Tue, 15 Mar 2016 16:31:01 -0700
From:	Kamal Mostafa <kamal@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Konstantin Khlebnikov <koct9i@...il.com>,
	Miklos Szeredi <miklos@...redi.hu>,
	Kamal Mostafa <kamal@...onical.com>
Subject: [PATCH 4.2.y-ckt 67/98] ovl: copy new uid/gid into overlayfs runtime inode

4.2.8-ckt6 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Konstantin Khlebnikov <koct9i@...il.com>

commit b81de061fa59f17d2730aabb1b84419ef3913810 upstream.

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@...il.com>
Signed-off-by: Miklos Szeredi <miklos@...redi.hu>
Signed-off-by: Kamal Mostafa <kamal@...onical.com>
---
 fs/overlayfs/inode.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 34300c2..0d28234 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -68,6 +68,8 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
 
 		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);
 	}
 	ovl_drop_write(dentry);
-- 
2.7.0