[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Mon, 8 Aug 2016 21:11:11 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Eryu Guan <eguan@...hat.com>,
Miklos Szeredi <mszeredi@...hat.com>,
Jeff Layton <jlayton@...hat.com>,
"J. Bruce Fields" <bfields@...hat.com>
Subject: [PATCH 4.4 36/68] locks: use file_inode()
4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miklos Szeredi <mszeredi@...hat.com>
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 <eguan@...hat.com>
Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Signed-off-by: Miklos Szeredi <mszeredi@...hat.com>
Reviewed-by: Jeff Layton <jlayton@...hat.com>
Signed-off-by: J. Bruce Fields <bfields@...hat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
fs/locks.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1602,7 +1602,7 @@ 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;
Powered by blists - more mailing lists