ISDN: hfcsusb: checking idx of ep configuration

commit f384e62a82ba5d85408405fdd6aeff89354deaa9 upstream.

The syzbot test with random endpoint address which made the idx is
overflow in the table of endpoint configuations.

this adds the checking for fixing the error report from
syzbot

KASAN: stack-out-of-bounds Read in hfcsusb_probe [1]
The patch tested by syzbot [2]

Reported-by: syzbot+8750abbc3a46ef47d509@syzkaller.appspotmail.com

[1]:
https://syzkaller.appspot.com/bug?id=30a04378dac680c5d521304a00a86156bb913522
[2]:
https://groups.google.com/d/msg/syzkaller-bugs/_6HBdge8F3E/OJn7wVNpBAAJ

Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Phong Tran 2019-07-15 22:08:14 +07:00 committed by Greg Kroah-Hartman
parent 22068d49d0
commit f13ee5ae0b

View file

@ -1967,6 +1967,9 @@ hfcsusb_probe(struct usb_interface *intf, const struct usb_device_id *id)
/* get endpoint base */
idx = ((ep_addr & 0x7f) - 1) * 2;
if (idx > 15)
return -EIO;
if (ep_addr & 0x80)
idx++;
attr = ep->desc.bmAttributes;