NET: cdc-phonet, handle empty phonet header

commit 468c3f924f043cad7a04f4f4d5224a2c9bc886c1 upstream.

Currently, for N 5800 XM I get:
cdc_phonet: probe of 1-6:1.10 failed with error -22

It's because phonet_header is empty. Extra altsetting looks like
there:
E 05 24 00 01 10 03 24 ab 05 24 06 0a 0b 04 24 fd  .$....$..$....$.
E 00                                               .

I don't see the header used anywhere so just check if the phonet
descriptor is there, not the structure itself.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/net/usb/cdc-phonet.c b/drivers/net/usb/cdc-phonet.c
index 33d5c579c5add542772afb6bf4327bdbb0ebc90b..605caaa721c467f18d52ec2effe15c9ecd5aec2d 100644 (file)
--- a/drivers/net/usb/cdc-phonet.c
+++ b/drivers/net/usb/cdc-phonet.c
@@ -325,13 +325,13 @@ int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
        static const char ifname[] = "usbpn%d";
        const struct usb_cdc_union_desc *union_header = NULL;
-       const struct usb_cdc_header_desc *phonet_header = NULL;
        const struct usb_host_interface *data_desc;
        struct usb_interface *data_intf;
        struct usb_device *usbdev = interface_to_usbdev(intf);
        struct net_device *dev;
        struct usbpn_dev *pnd;
        u8 *data;
+       int phonet = 0;
        int len, err;
 
        data = intf->altsetting->extra;
@@ -352,10 +352,7 @@ int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id)
                                        (struct usb_cdc_union_desc *)data;
                                break;
                        case 0xAB:
-                               if (phonet_header || dlen < 5)
-                                       break;
-                               phonet_header =
-                                       (struct usb_cdc_header_desc *)data;
+                               phonet = 1;
                                break;
                        }
                }
@@ -363,7 +360,7 @@ int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id)
                len -= dlen;
        }
 
-       if (!union_header || !phonet_header)
+       if (!union_header || !phonet)
                return -EINVAL;
 
        data_intf = usb_ifnum_to_if(usbdev, union_header->bSlaveInterface0);