From a323fefc6f5079844dc62ffeb54f491d0242ca35 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 3 Jan 2017 16:39:43 +0100 Subject: USB: serial: io_ti: fix NULL-deref at open Fix NULL-pointer dereference when clearing halt at open should a malicious device lack the expected endpoints when in download mode. Unable to handle kernel NULL pointer dereference at virtual address 00000030 ... [] (edge_open [io_ti]) from [] (serial_port_activate+0x68/0x98 [usbserial]) [] (serial_port_activate [usbserial]) from [] (tty_port_open+0x9c/0xe8) [] (tty_port_open) from [] (serial_open+0x48/0x6c [usbserial]) [] (serial_open [usbserial]) from [] (tty_open+0xcc/0x5cc) Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable Signed-off-by: Johan Hovold --- drivers/usb/serial/io_ti.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/usb/serial') diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c index c339163698eb..bf8a4f432f4b 100644 --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -2546,6 +2546,13 @@ static int edge_startup(struct usb_serial *serial) int status; u16 product_id; + /* Make sure we have the required endpoints when in download mode. */ + if (serial->interface->cur_altsetting->desc.bNumEndpoints > 1) { + if (serial->num_bulk_in < serial->num_ports || + serial->num_bulk_out < serial->num_ports) + return -ENODEV; + } + /* create our private serial structure */ edge_serial = kzalloc(sizeof(struct edgeport_serial), GFP_KERNEL); if (!edge_serial) -- cgit v1.2.3