USB: serial: io_edgeport: fix NULL-deref at open

Fix NULL-pointer dereference when initialising URBs at open should a
non-EPIC device lack a bulk-in or interrupt-in endpoint.

Unable to handle kernel NULL pointer dereference at virtual address 00000028
...
PC is at edge_open+0x24c/0x3e8 [io_edgeport]

Note that the EPIC-device probe path has the required sanity checks so
this makes those checks partially redundant.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index dcc0c58aaad5adaf89bdd535d4cd9699445de3ac..d50e5773483f5494be90ff42633cff70012079cc 100644 (file)
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -2751,6 +2751,11 @@ static int edge_startup(struct usb_serial *serial)
                                        EDGE_COMPATIBILITY_MASK1,
                                        EDGE_COMPATIBILITY_MASK2 };
 
+       if (serial->num_bulk_in < 1 || serial->num_interrupt_in < 1) {
+               dev_err(&serial->interface->dev, "missing endpoints\n");
+               return -ENODEV;
+       }
+
        dev = serial->dev;
 
        /* create our private serial structure */