Revert "cdc-acm: hardening against malicious devices"

This reverts commit 2ad9d544f2497a7bf239c34bd2b86fd19683dbb5.

Drop bogus sanity check; an interface in the active configuration will
always have a current altsetting assigned by USB core.

Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200921135951.24045-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index f3803fa..3b87e97 100644 (file)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1197,9 +1197,6 @@ static int acm_probe(struct usb_interface *intf,
                return -EINVAL;
        }
 
-       if (!intf->cur_altsetting)
-               return -EINVAL;
-
        if (!buflen) {
                if (intf->cur_altsetting->endpoint &&
                                intf->cur_altsetting->endpoint->extralen &&
@@ -1253,8 +1250,6 @@ static int acm_probe(struct usb_interface *intf,
                dev_dbg(&intf->dev, "no interfaces\n");
                return -ENODEV;
        }
-       if (!data_interface->cur_altsetting || !control_interface->cur_altsetting)
-               return -ENODEV;
 
        if (data_intf_num != call_intf_num)
                dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");