kvm: nVMX: Fix kernel panics induced by illegal INVEPT/INVVPID types

kvm: nVMX: Fix kernel panics induced by illegal INVEPT/INVVPID types

commit 85c856b39b479dde410ddd09df1da745343010c9 upstream

Bitwise shifts by amounts greater than or equal to the width of the left
operand are undefined. A malicious guest can exploit this to crash a
32-bit host, due to the BUG_ON(1)'s in handle_{invept,invvpid}.

Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <1477496318-17681-1-git-send-email-jmattson@google.com>
[Change 1UL to 1, to match the range check on the shift count. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[jwang: port from linux-4.9 to 4.4 ]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>