From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754002AbcHHTaj (ORCPT ); Mon, 8 Aug 2016 15:30:39 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36605 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932389AbcHHTSp (ORCPT ); Mon, 8 Aug 2016 15:18:45 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eryu Guan , Miklos Szeredi , Jeff Layton , "J. Bruce Fields" Subject: [PATCH 4.6 52/96] locks: use file_inode() Date: Mon, 8 Aug 2016 21:11:15 +0200 Message-Id: <20160808180246.167528052@linuxfoundation.org> X-Mailer: git-send-email 2.9.2 In-Reply-To: <20160808180243.898163389@linuxfoundation.org> References: <20160808180243.898163389@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Miklos Szeredi commit 6343a2120862f7023006c8091ad95c1f16a32077 upstream. (Another one for the f_path debacle.) ltp fcntl33 testcase caused an Oops in selinux_file_send_sigiotask. The reason is that generic_add_lease() used filp->f_path.dentry->inode while all the others use file_inode(). This makes a difference for files opened on overlayfs since the former will point to the overlay inode the latter to the underlying inode. So generic_add_lease() added the lease to the overlay inode and generic_delete_lease() removed it from the underlying inode. When the file was released the lease remained on the overlay inode's lock list, resulting in use after free. Reported-by: Eryu Guan Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Signed-off-by: Miklos Szeredi Reviewed-by: Jeff Layton Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/locks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/locks.c +++ b/fs/locks.c @@ -1628,7 +1628,7 @@ generic_add_lease(struct file *filp, lon { struct file_lock *fl, *my_fl = NULL, *lease; struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; + struct inode *inode = file_inode(filp); struct file_lock_context *ctx; bool is_deleg = (*flp)->fl_flags & FL_DELEG; int error;