[PATCH 4.4 226/241] net: cdc_ncm: GetNtbFormat endian fix

From: Greg Kroah-Hartman
Date: Sun Jun 09 2019 - 13:10:24 EST


From: BjÃrn Mork <bjorn@xxxxxxx>

commit 6314dab4b8fb8493d810e175cb340376052c69b6 upstream.

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.hutchings@xxxxxxxxxxxxxxx>
Fixes: 2b02c20ce0c2 ("cdc_ncm: Set NTB format again after altsetting switch for Huawei devices")
Cc: Enrico Mioso <mrkiko.rs@xxxxxxxxx>
Cc: Christian Panton <christian@xxxxxxxxxx>
Signed-off-by: BjÃrn Mork <bjorn@xxxxxxx>
Acked-By: Enrico Mioso <mrkiko.rs@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/usb/cdc_ncm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -727,7 +727,7 @@ int cdc_ncm_bind_common(struct usbnet *d
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)
@@ -841,7 +841,7 @@ int cdc_ncm_bind_common(struct usbnet *d
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