From 5afeef2366db14587b65558bbfd5a067542e07fb Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 3 Jan 2017 16:39:59 +0100 Subject: [PATCH] USB: serial: oti6858: fix NULL-deref at open Fix NULL-pointer dereference in open() should the device lack the expected endpoints: Unable to handle kernel NULL pointer dereference at virtual address 00000030 ... PC is at oti6858_open+0x30/0x1d0 [oti6858] Note that a missing interrupt-in endpoint would have caused open() to fail. Fixes: 49cdee0ed0fc ("USB: oti6858 usb-serial driver (in Nokia CA-42 cable)") Cc: stable Signed-off-by: Johan Hovold --- drivers/usb/serial/oti6858.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/usb/serial/oti6858.c b/drivers/usb/serial/oti6858.c index a4b88bc038b6..b8bf52bf7a94 100644 --- a/drivers/usb/serial/oti6858.c +++ b/drivers/usb/serial/oti6858.c @@ -134,6 +134,7 @@ static int oti6858_chars_in_buffer(struct tty_struct *tty); static int oti6858_tiocmget(struct tty_struct *tty); static int oti6858_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear); +static int oti6858_attach(struct usb_serial *serial); static int oti6858_port_probe(struct usb_serial_port *port); static int oti6858_port_remove(struct usb_serial_port *port); @@ -158,6 +159,7 @@ static struct usb_serial_driver oti6858_device = { .write_bulk_callback = oti6858_write_bulk_callback, .write_room = oti6858_write_room, .chars_in_buffer = oti6858_chars_in_buffer, + .attach = oti6858_attach, .port_probe = oti6858_port_probe, .port_remove = oti6858_port_remove, }; @@ -324,6 +326,20 @@ static void send_data(struct work_struct *work) usb_serial_port_softint(port); } +static int oti6858_attach(struct usb_serial *serial) +{ + unsigned char num_ports = serial->num_ports; + + if (serial->num_bulk_in < num_ports || + serial->num_bulk_out < num_ports || + serial->num_interrupt_in < num_ports) { + dev_err(&serial->interface->dev, "missing endpoints\n"); + return -ENODEV; + } + + return 0; +} + static int oti6858_port_probe(struct usb_serial_port *port) { struct oti6858_private *priv;