Patch "cifs: fix CIFS_IOC_GET_MNT_INFO oops" has been added to the 4.4-stable tree

Patch "cifs: fix CIFS_IOC_GET_MNT_INFO oops" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    cifs: fix CIFS_IOC_GET_MNT_INFO oops

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     cifs-fix-cifs_ioc_get_mnt_info-oops.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d8a6e505d6bba2250852fbc1c1c86fe68aaf9af3 Mon Sep 17 00:00:00 2001
From: David Disseldorp <ddiss@suse.de>
Date: Thu, 4 May 2017 00:41:13 +0200
Subject: cifs: fix CIFS_IOC_GET_MNT_INFO oops

From: David Disseldorp <ddiss@suse.de>

commit d8a6e505d6bba2250852fbc1c1c86fe68aaf9af3 upstream.

An open directory may have a NULL private_data pointer prior to readdir.

Fixes: 0de1f4c6f6c0 ("Add way to query server fs info for smb3")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/cifs/ioctl.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -272,6 +272,8 @@ long cifs_ioctl(struct file *filep, unsi
 				rc = -EOPNOTSUPP;
 			break;
 		case CIFS_IOC_GET_MNT_INFO:
+			if (pSMBFile == NULL)
+				break;
 			tcon = tlink_tcon(pSMBFile->tlink);
 			rc = smb_mnt_get_fsinfo(xid, tcon, (void __user *)arg);
 			break;


Patches currently in stable-queue which might be from ddiss@suse.de are

queue-4.4/cifs-fix-cifs_ioc_get_mnt_info-oops.patch
queue-4.4/target-fileio-fix-zero-length-read-and-write-handling.patch