--- /dev/null
+From d91a03b72c5f9c25e5b976f8f67bcf279601d644 Mon Sep 17 00:00:00 2001
+From: Lech Perczak <lech.perczak@gmail.com>
+Date: Fri, 1 Apr 2022 22:03:55 +0200
+Subject: [PATCH 1/3] cdc_ether: export usbnet_cdc_zte_rx_fixup
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Commit bfe9b9d2df66 ("cdc_ether: Improve ZTE MF823/831/910 handling")
+introduces a workaround for certain ZTE modems reporting invalid MAC
+addresses over CDC-ECM.
+The same issue was present on their RNDIS interface,which was fixed in
+commit a5a18bdf7453 ("rndis_host: Set valid random MAC on buggy devices").
+
+However, internal modem of ZTE MF286R router, on its RNDIS interface, also
+exhibits a second issue fixed already in CDC-ECM, of the device not
+respecting configured random MAC address. In order to share the fixup for
+this with rndis_host driver, export the workaround function, which will
+be re-used in the following commit in rndis_host.
+
+Cc: Kristian Evensen <kristian.evensen@gmail.com>
+Cc: Bjørn Mork <bjorn@mork.no>
+Cc: Oliver Neukum <oliver@neukum.org>
+Signed-off-by: Lech Perczak <lech.perczak@gmail.com>
+---
+ drivers/net/usb/cdc_ether.c | 3 ++-
+ include/linux/usb/usbnet.h | 1 +
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/net/usb/cdc_ether.c
++++ b/drivers/net/usb/cdc_ether.c
+@@ -466,7 +466,7 @@ static int usbnet_cdc_zte_bind(struct us
+ * device MAC address has been updated). Always set MAC address to that of the
+ * device.
+ */
+-static int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
++int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+ {
+ if (skb->len < ETH_HLEN || !(skb->data[0] & 0x02))
+ return 1;
+@@ -476,6 +476,7 @@ static int usbnet_cdc_zte_rx_fixup(struc
+
+ return 1;
+ }
++EXPORT_SYMBOL_GPL(usbnet_cdc_zte_rx_fixup);
+
+ /* Ensure correct link state
+ *
+--- a/include/linux/usb/usbnet.h
++++ b/include/linux/usb/usbnet.h
+@@ -215,6 +215,7 @@ extern int usbnet_ether_cdc_bind(struct
+ extern int usbnet_cdc_bind(struct usbnet *, struct usb_interface *);
+ extern void usbnet_cdc_unbind(struct usbnet *, struct usb_interface *);
+ extern void usbnet_cdc_status(struct usbnet *, struct urb *);
++extern int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb);
+
+ /* CDC and RNDIS support the same host-chosen packet filters for IN transfers */
+ #define DEFAULT_FILTER (USB_CDC_PACKET_TYPE_BROADCAST \
--- /dev/null
+From 69a9efb689b43fedf5f19431f1889aa6b8d35d55 Mon Sep 17 00:00:00 2001
+From: Lech Perczak <lech.perczak@gmail.com>
+Date: Fri, 1 Apr 2022 22:04:01 +0200
+Subject: [PATCH 2/3] rndis_host: enable the bogus MAC fixup for ZTE devices
+ from cdc_ether
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Certain ZTE modems, namely: MF823. MF831, MF910, built-in modem from
+MF286R, expose both CDC-ECM and RNDIS network interfaces.
+They have a trait of ignoring the locally-administered MAC address
+configured on the interface both in CDC-ECM and RNDIS part,
+and this leads to dropping of incoming traffic by the host.
+However, the workaround was only present in CDC-ECM, and MF286R
+explicitly requires it in RNDIS mode.
+
+Re-use the workaround in rndis_host as well, to fix operation of MF286R
+module, some versions of which expose only the RNDIS interface. Do so by
+introducing new flag, RNDIS_DRIVER_DATA_DST_MAC_FIXUP, and testing for it
+in rndis_rx_fixup. This is required, as RNDIS uses frame batching, and all
+of the packets inside the batch need the fixup. This might introduce a
+performance penalty, because test is done for every returned Ethernet
+frame.
+
+Apply the workaround to both "flavors" of RNDIS interfaces, as older ZTE
+modems, like MF823 found in the wild, report the USB_CLASS_COMM class
+interfaces, while MF286R reports USB_CLASS_WIRELESS_CONTROLLER.
+
+Suggested-by: Bjørn Mork <bjorn@mork.no>
+Cc: Kristian Evensen <kristian.evensen@gmail.com>
+Cc: Oliver Neukum <oliver@neukum.org>
+Signed-off-by: Lech Perczak <lech.perczak@gmail.com>
+---
+ drivers/net/usb/rndis_host.c | 32 ++++++++++++++++++++++++++++++++
+ include/linux/usb/rndis_host.h | 1 +
+ 2 files changed, 33 insertions(+)
+
+--- a/drivers/net/usb/rndis_host.c
++++ b/drivers/net/usb/rndis_host.c
+@@ -485,10 +485,14 @@ EXPORT_SYMBOL_GPL(rndis_unbind);
+ */
+ int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+ {
++ bool dst_mac_fixup;
++
+ /* This check is no longer done by usbnet */
+ if (skb->len < dev->net->hard_header_len)
+ return 0;
+
++ dst_mac_fixup = !!(dev->driver_info->data & RNDIS_DRIVER_DATA_DST_MAC_FIXUP);
++
+ /* peripheral may have batched packets to us... */
+ while (likely(skb->len)) {
+ struct rndis_data_hdr *hdr = (void *)skb->data;
+@@ -523,10 +527,17 @@ int rndis_rx_fixup(struct usbnet *dev, s
+ break;
+ skb_pull(skb, msg_len - sizeof *hdr);
+ skb_trim(skb2, data_len);
++
++ if (unlikely(dst_mac_fixup))
++ usbnet_cdc_zte_rx_fixup(dev, skb2);
++
+ usbnet_skb_return(dev, skb2);
+ }
+
+ /* caller will usbnet_skb_return the remaining packet */
++ if (unlikely(dst_mac_fixup))
++ usbnet_cdc_zte_rx_fixup(dev, skb);
++
+ return 1;
+ }
+ EXPORT_SYMBOL_GPL(rndis_rx_fixup);
+@@ -600,6 +611,17 @@ static const struct driver_info rndis_po
+ .tx_fixup = rndis_tx_fixup,
+ };
+
++static const struct driver_info zte_rndis_info = {
++ .description = "ZTE RNDIS device",
++ .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
++ .data = RNDIS_DRIVER_DATA_DST_MAC_FIXUP,
++ .bind = rndis_bind,
++ .unbind = rndis_unbind,
++ .status = rndis_status,
++ .rx_fixup = rndis_rx_fixup,
++ .tx_fixup = rndis_tx_fixup,
++};
++
+ /*-------------------------------------------------------------------------*/
+
+ static const struct usb_device_id products [] = {
+@@ -609,6 +631,16 @@ static const struct usb_device_id produc
+ USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
+ .driver_info = (unsigned long) &rndis_poll_status_info,
+ }, {
++ /* ZTE WWAN modules */
++ USB_VENDOR_AND_INTERFACE_INFO(0x19d2,
++ USB_CLASS_WIRELESS_CONTROLLER, 1, 3),
++ .driver_info = (unsigned long)&zte_rndis_info,
++}, {
++ /* ZTE WWAN modules, ACM flavour */
++ USB_VENDOR_AND_INTERFACE_INFO(0x19d2,
++ USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
++ .driver_info = (unsigned long)&zte_rndis_info,
++}, {
+ /* Hytera Communications DMR radios' "Radio to PC Network" */
+ USB_VENDOR_AND_INTERFACE_INFO(0x238b,
+ USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
+--- a/include/linux/usb/rndis_host.h
++++ b/include/linux/usb/rndis_host.h
+@@ -197,6 +197,7 @@ struct rndis_keepalive_c { /* IN (option
+
+ /* Flags for driver_info::data */
+ #define RNDIS_DRIVER_DATA_POLL_STATUS 1 /* poll status before control */
++#define RNDIS_DRIVER_DATA_DST_MAC_FIXUP 2 /* device ignores configured MAC address */
+
+ extern void rndis_status(struct usbnet *dev, struct urb *urb);
+ extern int
--- /dev/null
+From 1bfbe1799b9ec5d00f7f032d6e7db1980e466aeb Mon Sep 17 00:00:00 2001
+From: Lech Perczak <lech.perczak@gmail.com>
+Date: Sat, 2 Apr 2022 02:19:57 +0200
+Subject: [PATCH 3/3] rndis_host: limit scope of bogus MAC address detection to
+ ZTE devices
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Reporting of bogus MAC addresses and ignoring configuration of new
+destination address wasn't observed outside of a range of ZTE devices,
+among which this seems to be the common bug. Align rndis_host driver
+with implementation found in cdc_ether, which also limits this workaround
+to ZTE devices.
+
+Suggested-by: Bjørn Mork <bjorn@mork.no>
+Cc: Kristian Evensen <kristian.evensen@gmail.com>
+Cc: Oliver Neukum <oliver@neukum.org>
+Signed-off-by: Lech Perczak <lech.perczak@gmail.com>
+---
+ drivers/net/usb/rndis_host.c | 17 ++++++++++++-----
+ 1 file changed, 12 insertions(+), 5 deletions(-)
+
+--- a/drivers/net/usb/rndis_host.c
++++ b/drivers/net/usb/rndis_host.c
+@@ -418,10 +418,7 @@ generic_rndis_bind(struct usbnet *dev, s
+ goto halt_fail_and_release;
+ }
+
+- if (bp[0] & 0x02)
+- eth_hw_addr_random(net);
+- else
+- ether_addr_copy(net->dev_addr, bp);
++ ether_addr_copy(net->dev_addr, bp);
+
+ /* set a nonzero filter to enable data transfers */
+ memset(u.set, 0, sizeof *u.set);
+@@ -463,6 +460,16 @@ static int rndis_bind(struct usbnet *dev
+ return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS);
+ }
+
++static int zte_rndis_bind(struct usbnet *dev, struct usb_interface *intf)
++{
++ int status = rndis_bind(dev, intf);
++
++ if (!status && (dev->net->dev_addr[0] & 0x02))
++ eth_hw_addr_random(dev->net);
++
++ return status;
++}
++
+ void rndis_unbind(struct usbnet *dev, struct usb_interface *intf)
+ {
+ struct rndis_halt *halt;
+@@ -615,7 +622,7 @@ static const struct driver_info zte_rndi
+ .description = "ZTE RNDIS device",
+ .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
+ .data = RNDIS_DRIVER_DATA_DST_MAC_FIXUP,
+- .bind = rndis_bind,
++ .bind = zte_rndis_bind,
+ .unbind = rndis_unbind,
+ .status = rndis_status,
+ .rx_fixup = rndis_rx_fixup,
projects / openwrt / openwrt.git / commitdiff