From: Bjørn Mork <bjorn@xxxxxxx> commit 4d06dd537f95683aba3651098ae288b7cbff8274 upstream. usbnet_link_change will call schedule_work and should be avoided if bind is failing. Otherwise we will end up with scheduled work referring to a netdev which has gone away. Instead of making the call conditional, we can just defer it to usbnet_probe, using the driver_info flag made for this purpose. CVE-2016-3951 Fixes: 8a34b0ae8778 ("usbnet: cdc_ncm: apply usbnet_link_change") Reported-by: Andrey Konovalov <andreyknvl@xxxxxxxxx> Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Bjørn Mork <bjorn@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [ciwillia@xxxxxxxxxxx: backported to 3.14: adjusted context] Signed-off-by: Charles (Chas) Williams <ciwillia@xxxxxxxxxxx> --- drivers/net/usb/cdc_ncm.c | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index c663722..1f24dfc 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -564,24 +564,13 @@ EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting); static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf) { - int ret; - /* MBIM backwards compatible function? */ cdc_ncm_select_altsetting(dev, intf); if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) return -ENODEV; /* NCM data altsetting is always 1 */ - ret = cdc_ncm_bind_common(dev, intf, 1); - - /* - * We should get an event when network connection is "connected" or - * "disconnected". Set network connection in "disconnected" state - * (carrier is OFF) during attach, so the IP network stack does not - * start IPv6 negotiation and more. - */ - usbnet_link_change(dev, 0, 0); - return ret; + return cdc_ncm_bind_common(dev, intf, 1); } static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max) @@ -1110,7 +1099,8 @@ static int cdc_ncm_check_connect(struct usbnet *dev) static const struct driver_info cdc_ncm_info = { .description = "CDC NCM", - .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET, + .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET + | FLAG_LINK_INTR, .bind = cdc_ncm_bind, .unbind = cdc_ncm_unbind, .check_connect = cdc_ncm_check_connect, @@ -1124,7 +1114,7 @@ static const struct driver_info cdc_ncm_info = { static const struct driver_info wwan_info = { .description = "Mobile Broadband Network Device", .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET - | FLAG_WWAN, + | FLAG_LINK_INTR | FLAG_WWAN, .bind = cdc_ncm_bind, .unbind = cdc_ncm_unbind, .check_connect = cdc_ncm_check_connect, @@ -1138,7 +1128,7 @@ static const struct driver_info wwan_info = { static const struct driver_info wwan_noarp_info = { .description = "Mobile Broadband Network Device (NO ARP)", .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET - | FLAG_WWAN | FLAG_NOARP, + | FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP, .bind = cdc_ncm_bind, .unbind = cdc_ncm_unbind, .check_connect = cdc_ncm_check_connect, -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html