1 files changed, 82 insertions, 22 deletions

diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
index 25ba7eca9a13..c9f3281506af 100644
--- a/drivers/net/usb/cdc_mbim.c
+++ b/drivers/net/usb/cdc_mbim.c
@@ -21,6 +21,8 @@
 #include <linux/usb/usbnet.h>
 #include <linux/usb/cdc-wdm.h>
 #include <linux/usb/cdc_ncm.h>
+#include <net/ipv6.h>
+#include <net/addrconf.h>
 
 /* driver specific data - must match cdc_ncm usage */
 struct cdc_mbim_state {
@@ -42,13 +44,11 @@ static int cdc_mbim_manage_power(struct usbnet *dev, int on)
         if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
                 /* need autopm_get/put here to ensure the usbcore sees the new value */
                 rv = usb_autopm_get_interface(dev->intf);
-                if (rv < 0)
-                        goto err;
                 dev->intf->needs_remote_wakeup = on;
-                usb_autopm_put_interface(dev->intf);
+                if (!rv)
+                        usb_autopm_put_interface(dev->intf);
         }
-err:
-        return rv;
+        return 0;
 }
 
 static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
@@ -173,7 +173,7 @@ static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb
         }
 
         spin_lock_bh(&ctx->mtx);
-        skb_out = cdc_ncm_fill_tx_frame(ctx, skb, sign);
+        skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
         spin_unlock_bh(&ctx->mtx);
         return skb_out;
 
@@ -184,6 +184,60 @@ error:
         return NULL;
 }
 
+/* Some devices are known to send Neigbor Solicitation messages and
+ * require Neigbor Advertisement replies.  The IPv6 core will not
+ * respond since IFF_NOARP is set, so we must handle them ourselves.
+ */
+static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
+{
+        struct ipv6hdr *iph = (void *)buf;
+        struct nd_msg *msg = (void *)(iph + 1);
+        struct net_device *netdev;
+        struct inet6_dev *in6_dev;
+        bool is_router;
+
+        /* we'll only respond to requests from unicast addresses to
+         * our solicited node addresses.
+         */
+        if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
+            !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
+                return;
+
+        /* need to send the NA on the VLAN dev, if any */
+        if (tci)
+                netdev = __vlan_find_dev_deep(dev->net, htons(ETH_P_8021Q),
+                                              tci);
+        else
+                netdev = dev->net;
+        if (!netdev)
+                return;
+
+        in6_dev = in6_dev_get(netdev);
+        if (!in6_dev)
+                return;
+        is_router = !!in6_dev->cnf.forwarding;
+        in6_dev_put(in6_dev);
+
+        /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
+        ipv6_stub->ndisc_send_na(netdev, NULL, &iph->saddr, &msg->target,
+                                 is_router /* router */,
+                                 true /* solicited */,
+                                 false /* override */,
+                                 true /* inc_opt */);
+}
+
+static bool is_neigh_solicit(u8 *buf, size_t len)
+{
+        struct ipv6hdr *iph = (void *)buf;
+        struct nd_msg *msg = (void *)(iph + 1);
+
+        return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
+                iph->nexthdr == IPPROTO_ICMPV6 &&
+                msg->icmph.icmp6_code == 0 &&
+                msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
+}
+
+
 static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
 {
         __be16 proto = htons(ETH_P_802_3);
@@ -198,6 +252,8 @@ static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_
                         proto = htons(ETH_P_IP);
                         break;
                 case 0x60:
+                        if (is_neigh_solicit(buf, len))
+                                do_neigh_solicit(dev, buf, tci);
                         proto = htons(ETH_P_IPV6);
                         break;
                 default:
@@ -313,15 +369,13 @@ error:
 
 static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
 {
-        int ret = 0;
+        int ret = -ENODEV;
         struct usbnet *dev = usb_get_intfdata(intf);
         struct cdc_mbim_state *info = (void *)&dev->data;
         struct cdc_ncm_ctx *ctx = info->ctx;
 
-        if (ctx == NULL) {
-                ret = -1;
+        if (!ctx)
                 goto error;
-        }
 
         /*
          * Both usbnet_suspend() and subdriver->suspend() MUST return 0
@@ -354,7 +408,7 @@ static int cdc_mbim_resume(struct usb_interface *intf)
         if (ret < 0)
                 goto err;
         ret = usbnet_resume(intf);
-        if (ret < 0 && callsub && info->subdriver->suspend)
+        if (ret < 0 && callsub)
                 info->subdriver->suspend(intf, PMSG_SUSPEND);
 err:
         return ret;
@@ -371,9 +425,18 @@ static const struct driver_info cdc_mbim_info = {
 };
 
 /* MBIM and NCM devices should not need a ZLP after NTBs with
- * dwNtbOutMaxSize length. This driver_info is for the exceptional
- * devices requiring it anyway, allowing them to be supported without
- * forcing the performance penalty on all the sane devices.
+ * dwNtbOutMaxSize length. Nevertheless, a number of devices from
+ * different vendor IDs will fail unless we send ZLPs, forcing us
+ * to make this the default.
+ *
+ * This default may cause a performance penalty for spec conforming
+ * devices wanting to take advantage of optimizations possible without
+ * ZLPs.  A whitelist is added in an attempt to avoid this for devices
+ * known to conform to the MBIM specification.
+ *
+ * All known devices supporting NCM compatibility mode are also
+ * conforming to the NCM and MBIM specifications. For this reason, the
+ * NCM subclass entry is also in the ZLP whitelist.
  */
 static const struct driver_info cdc_mbim_info_zlp = {
         .description = "CDC MBIM",
@@ -396,16 +459,13 @@ static const struct usb_device_id mbim_devs[] = {
         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
           .driver_info = (unsigned long)&cdc_mbim_info,
         },
-        /* Sierra Wireless MC7710 need ZLPs */
-        { USB_DEVICE_AND_INTERFACE_INFO(0x1199, 0x68a2, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
-          .driver_info = (unsigned long)&cdc_mbim_info_zlp,
-        },
-        /* HP hs2434 Mobile Broadband Module needs ZLPs */
-        { USB_DEVICE_AND_INTERFACE_INFO(0x3f0, 0x4b1d, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
-          .driver_info = (unsigned long)&cdc_mbim_info_zlp,
+        /* ZLP conformance whitelist: All Ericsson MBIM devices */
+        { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
+          .driver_info = (unsigned long)&cdc_mbim_info,
         },
+        /* default entry */
         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
-          .driver_info = (unsigned long)&cdc_mbim_info,
+          .driver_info = (unsigned long)&cdc_mbim_info_zlp,
         },
         {
         },