diff options
| author | Miklos Szeredi <mszeredi@redhat.com> | 2016-07-01 14:56:07 +0200 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-07-12 08:47:18 -0400 |
| commit | 870957bfa39499b7d0a81b83f30d0c428275f6e6 (patch) | |
| tree | f6841b2dafd7fb38774107cfd6532f658768feb0 | |
| parent | 81c379f551f6e871f9de997b026a7cf432cb34ee (diff) | |
locks: use file_inode()
[ Upstream commit 6343a2120862f7023006c8091ad95c1f16a32077 ]
(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@redhat.com>
Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
| -rw-r--r-- | fs/locks.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/locks.c b/fs/locks.c index 298d1f5c66f0..253ca5c2b9c7 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1580,7 +1580,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr { struct file_lock *fl, **before, **my_before = NULL, *lease; struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; + struct inode *inode = file_inode(filp); bool is_deleg = (*flp)->fl_flags & FL_DELEG; int error; LIST_HEAD(dispose); |