From 550845d02afb926d50d1487f9e2b954270c83963 Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Tue, 16 May 2017 19:18:55 +0200 Subject: [PATCH 1/1] char: lp: fix possible integer overflow in lp_setup() commit 3e21f4af170bebf47c187c1ff8bf155583c9f3b1 upstream. 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 Cc: Ben Hutchings Signed-off-by: Willy Tarreau Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/char/lp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/char/lp.c b/drivers/char/lp.c index 97c3edb95ae7..bb8e370c9c48 100644 --- a/drivers/char/lp.c +++ b/drivers/char/lp.c @@ -858,7 +858,11 @@ 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; } -- 2.39.2