diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c index 13f7705fd679..2e025ddcef21 100644 --- a/drivers/net/usb/cdc_mbim.c +++ b/drivers/net/usb/cdc_mbim.c @@ -120,6 +120,16 @@ static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf) cdc_ncm_unbind(dev, intf); } +/* verify that the ethernet protocol is IPv4 or IPv6 */ +static bool is_ip_proto(__be16 proto) +{ + switch (proto) { + case htons(ETH_P_IP): + case htons(ETH_P_IPV6): + return true; + } + return false; +} static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) { @@ -128,6 +138,7 @@ static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb struct cdc_ncm_ctx *ctx = info->ctx; __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN); u16 tci = 0; + bool is_ip; u8 *c; if (!ctx) @@ -137,25 +148,32 @@ static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb if (skb->len <= ETH_HLEN) goto error; + /* Some applications using e.g. packet sockets will + * bypass the VLAN acceleration and create tagged + * ethernet frames directly. We primarily look for + * the accelerated out-of-band tag, but fall back if + * required + */ + skb_reset_mac_header(skb); + if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN && + __vlan_get_tag(skb, &tci) == 0) { + is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto); + skb_pull(skb, VLAN_ETH_HLEN); + } else { + is_ip = is_ip_proto(eth_hdr(skb)->h_proto); + skb_pull(skb, ETH_HLEN); + } + /* mapping VLANs to MBIM sessions: * no tag => IPS session <0> * 1 - 255 => IPS session * 256 - 511 => DSS session * 512 - 4095 => unsupported, drop */ - vlan_get_tag(skb, &tci); - switch (tci & 0x0f00) { case 0x0000: /* VLAN ID 0 - 255 */ - /* verify that datagram is IPv4 or IPv6 */ - skb_reset_mac_header(skb); - switch (eth_hdr(skb)->h_proto) { - case htons(ETH_P_IP): - case htons(ETH_P_IPV6): - break; - default: + if (!is_ip) goto error; - } c = (u8 *)&sign; c[3] = tci; break; @@ -169,7 +187,6 @@ static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb "unsupported tci=0x%04x\n", tci); goto error; } - skb_pull(skb, ETH_HLEN); } spin_lock_bh(&ctx->mtx);