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>
This commit is contained in:
Willy Tarreau 2017-05-16 19:18:55 +02:00 committed by Greg Kroah-Hartman
parent 2ea659a9ef
commit 3e21f4af17

View file

@ -859,7 +859,11 @@ static int __init lp_setup (char *str)
} else if (!strcmp(str, "auto")) {
parport_nr[0] = LP_PARPORT_AUTO;
} else if (!strcmp(str, "none")) {
parport_nr[parport_ptr++] = LP_PARPORT_NONE;
if (parport_ptr < LP_NO)
parport_nr[parport_ptr++] = LP_PARPORT_NONE;
else
printk(KERN_INFO "lp: too many ports, %s ignored.\n",
str);
} else if (!strcmp(str, "reset")) {
reset = 1;
}