misc: mic: Fix for double fetch security bug in VOP driver

misc: mic: Fix for double fetch security bug in VOP driver

commit 9bf292bfca94694a721449e3fd752493856710f6 upstream.

The MIC VOP driver does two successive reads from user space to read a
variable length data structure. Kernel memory corruption can result if
the data structure changes between the two reads. This patch disallows
the chance of this happening.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116651
Reported by: Pengfei Wang <wpengfeinudt@gmail.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>