cifs: check rsp for NULL before dereferencing in SMB2_open
authorRonnie Sahlberg <lsahlber@redhat.com>
Fri, 8 Sep 2017 00:37:35 +0000 (10:37 +1000)
committerSteve French <smfrench@gmail.com>
Tue, 12 Sep 2017 23:11:44 +0000 (18:11 -0500)
commitbf2afee14e07de16d3cafc67edbfc2a3cc65e4bc
treeaba3efa9b9ef3af8c4d233c6acddc47c07fcc946
parent52269718dc2cf2585d7a2828f31d46ef46e68000
cifs: check rsp for NULL before dereferencing in SMB2_open

In SMB2_open there are several paths where the SendReceive2
call will return an error before it sets rsp_iov.iov_base
thus leaving iov_base uninitialized.

Thus we need to check rsp before we dereference it in
the call to get_rfc1002_length().

A report of this issue was previously reported in
http://www.spinics.net/lists/linux-cifs/msg12846.html

RH-bugzilla : 1476151

Version 2 :
* Lets properly initialize rsp_iov before we use it.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>.
Signed-off-by: Steve French <smfrench@gmail.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
CC: Stable <stable@vger.kernel.org>
fs/cifs/smb2pdu.c