char: lp: fix possible integer overflow in lp_setup()

char: lp: fix possible integer overflow in lp_setup()

The lp_setup() code doesn't apply any bounds checking when passing
"lp=none", and only in this case, resulting in an overflow of the
parport_nr[] array. All versions in Git history are affected.

Reported-By: Roee Hay <roee.hay@hcl.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 3e21f4af170bebf47c187c1ff8bf155583c9f3b1)

Orabug: 26174869
CVE-2017-1000363

Signed-off-by: Kirtikar Kashyap <kirtikar.kashyap@oracle.com>
Reviewed-by: Jack Vogel <jack.vogel@oracle.com>