| Message ID | 20220413001158.1202194-3-lech.perczak@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | rndis_host: handle bogus MAC addresses in ZTE RNDIS devices | expand |
W dniu 2022-04-13 o 02:11, Lech Perczak pisze: > 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_BOGUS_MAC, and testing for it in And I just noticed that I forgot to rename that flag here, as well as one unneded whitespace change creeped in. Will resend V3 shortly. > 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> > --- > v2: > - Ensured that MAC fixup is applied to all Ethernet frames inside an > RNDIS batch. Thanks to Bjørn for finding the issue. > - Introduced new driver flag to facilitate the above. > > drivers/net/usb/rndis_host.c | 33 ++++++++++++++++++++++++++++++++- > include/linux/usb/rndis_host.h | 1 + > 2 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c > index 247f58cb0f84..18b27a4ed8bd 100644 > --- 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, struct sk_buff *skb) > 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); > @@ -578,7 +589,6 @@ rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) > } > EXPORT_SYMBOL_GPL(rndis_tx_fixup); > > - > static const struct driver_info rndis_info = { > .description = "RNDIS device", > .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT, > @@ -600,6 +610,17 @@ static const struct driver_info rndis_poll_status_info = { > .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 [] = { > @@ -613,6 +634,16 @@ static const struct usb_device_id products [] = { > USB_VENDOR_AND_INTERFACE_INFO(0x238b, > USB_CLASS_COMM, 2 /* ACM */, 0x0ff), > .driver_info = (unsigned long)&rndis_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, > }, { > /* RNDIS is MSFT's un-official variant of CDC ACM */ > USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff), > diff --git a/include/linux/usb/rndis_host.h b/include/linux/usb/rndis_host.h > index 809bccd08455..cc42db51bbba 100644 > --- a/include/linux/usb/rndis_host.h > +++ b/include/linux/usb/rndis_host.h > @@ -197,6 +197,7 @@ struct rndis_keepalive_c { /* IN (optionally OUT) */ > > /* 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
diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c index 247f58cb0f84..18b27a4ed8bd 100644 --- 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, struct sk_buff *skb) 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); @@ -578,7 +589,6 @@ rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) } EXPORT_SYMBOL_GPL(rndis_tx_fixup); - static const struct driver_info rndis_info = { .description = "RNDIS device", .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT, @@ -600,6 +610,17 @@ static const struct driver_info rndis_poll_status_info = { .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 [] = { @@ -613,6 +634,16 @@ static const struct usb_device_id products [] = { USB_VENDOR_AND_INTERFACE_INFO(0x238b, USB_CLASS_COMM, 2 /* ACM */, 0x0ff), .driver_info = (unsigned long)&rndis_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, }, { /* RNDIS is MSFT's un-official variant of CDC ACM */ USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff), diff --git a/include/linux/usb/rndis_host.h b/include/linux/usb/rndis_host.h index 809bccd08455..cc42db51bbba 100644 --- a/include/linux/usb/rndis_host.h +++ b/include/linux/usb/rndis_host.h @@ -197,6 +197,7 @@ struct rndis_keepalive_c { /* IN (optionally OUT) */ /* 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
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_BOGUS_MAC, 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> --- v2: - Ensured that MAC fixup is applied to all Ethernet frames inside an RNDIS batch. Thanks to Bjørn for finding the issue. - Introduced new driver flag to facilitate the above. drivers/net/usb/rndis_host.c | 33 ++++++++++++++++++++++++++++++++- include/linux/usb/rndis_host.h | 1 + 2 files changed, 33 insertions(+), 1 deletion(-)