Thank you very much Ben and bjorn, for the spot, the fix, and overall helping 
me learn new things.

Acked-By: Enrico Mioso <mrkiko...@gmail.com>



On Wed, 15 Nov 2017, Bjørn Mork wrote:

Date: Wed, 15 Nov 2017 09:35:02
From: Bjørn Mork <bj...@mork.no>
To: netdev@vger.kernel.org
Cc: Oliver Neukum <oli...@neukum.org>,
    Ben Hutchings <ben.hutchi...@codethink.co.uk>, linux-...@vger.kernel.org,
    Bjørn Mork <bj...@mork.no>, Enrico Mioso <mrkiko...@gmail.com>,
    Christian Panton <christ...@panton.org>
Subject: [PATCH net,stable] net: cdc_ncm: GetNtbFormat endian fix

The GetNtbFormat and SetNtbFormat requests operate on 16 bit little
endian values. We get away with ignoring this most of the time, because
we only care about USB_CDC_NCM_NTB16_FORMAT which is 0x0000.  This
fails for USB_CDC_NCM_NTB32_FORMAT.

Fix comparison between LE value from device and constant by converting
the constant to LE.

Reported-by: Ben Hutchings <ben.hutchi...@codethink.co.uk>
Fixes: 2b02c20ce0c2 ("cdc_ncm: Set NTB format again after altsetting switch for 
Huawei devices")
Cc: Enrico Mioso <mrkiko...@gmail.com>
Cc: Christian Panton <christ...@panton.org>
Signed-off-by: Bjørn Mork <bj...@mork.no>
---
drivers/net/usb/cdc_ncm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 47cab1bde065..9e1b74590682 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -771,7 +771,7 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct 
usb_interface *intf, u8 data_
        int err;
        u8 iface_no;
        struct usb_cdc_parsed_header hdr;
-       u16 curr_ntb_format;
+       __le16 curr_ntb_format;

        ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
        if (!ctx)
@@ -889,7 +889,7 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct 
usb_interface *intf, u8 data_
                        goto error2;
                }

-               if (curr_ntb_format == USB_CDC_NCM_NTB32_FORMAT) {
+               if (curr_ntb_format == cpu_to_le16(USB_CDC_NCM_NTB32_FORMAT)) {
                        dev_info(&intf->dev, "resetting NTB format to 16-bit");
                        err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
                                               USB_TYPE_CLASS | USB_DIR_OUT
--
2.11.0

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