From a4abd7a80addb4a9547f7dfc7812566b60ec505c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= Date: Wed, 6 Dec 2017 20:21:24 +0100 Subject: [PATCH] usbnet: fix alignment for frames with no ethernet header MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The qmi_wwan minidriver support a 'raw-ip' mode where frames are received without any ethernet header. This causes alignment issues because the skbs allocated by usbnet are "IP aligned". Fix by allowing minidrivers to disable the additional alignment offset. This is implemented using a per-device flag, since the same minidriver also supports 'ethernet' mode. Fixes: 32f7adf633b9 ("net: qmi_wwan: support "raw IP" mode") Reported-and-tested-by: Jay Foster Signed-off-by: Bjørn Mork Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 2 ++ drivers/net/usb/usbnet.c | 5 ++++- include/linux/usb/usbnet.h | 1 + 3 files changed, 7 insertions(+), 1 deletion(-) --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -70,9 +70,11 @@ static void qmi_wwan_netdev_setup(struct net->hard_header_len = 0; net->addr_len = 0; net->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; + set_bit(EVENT_NO_IP_ALIGN, &dev->flags); netdev_dbg(net, "mode: raw IP\n"); } else if (!net->header_ops) { /* don't bother if already set */ ether_setup(net); + clear_bit(EVENT_NO_IP_ALIGN, &dev->flags); netdev_dbg(net, "mode: Ethernet\n"); } --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -482,7 +482,10 @@ static int rx_submit (struct usbnet *dev return -ENOLINK; } - skb = __netdev_alloc_skb_ip_align(dev->net, size, flags); + if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags)) + skb = __netdev_alloc_skb(dev->net, size, flags); + else + skb = __netdev_alloc_skb_ip_align(dev->net, size, flags); if (!skb) { netif_dbg(dev, rx_err, dev->net, "no rx skb\n"); usbnet_defer_kevent (dev, EVENT_RX_MEMORY); --- a/include/linux/usb/usbnet.h +++ b/include/linux/usb/usbnet.h @@ -79,6 +79,7 @@ struct usbnet { # define EVENT_RX_KILL 10 # define EVENT_LINK_CHANGE 11 # define EVENT_SET_RX_MODE 12 +# define EVENT_NO_IP_ALIGN 13 }; static inline struct usb_driver *driver_of(struct usb_interface *intf)