4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Willy Tarreau <w@xxxxxx>
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 <roee.hay@xxxxxxx>
Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/lp.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/char/lp.c
+++ b/drivers/char/lp.c
@@ -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;
}