target/linux/generic/backport-5.10/610-v5.13-12-net-8021q-resolve-forwarding-path-for-vlan-devices.patch

   1 From: Pablo Neira Ayuso <pablo@netfilter.org>
   2 Date: Wed, 24 Mar 2021 02:30:33 +0100
   3 Subject: [PATCH] net: 8021q: resolve forwarding path for vlan devices
   4
   5 Add .ndo_fill_forward_path for vlan devices.
   6
   7 For instance, assuming the following topology:
   8
   9                    IP forwarding
  10                   /             \
  11             eth0.100             eth0
  12             |
  13             eth0
  14             .
  15             .
  16             .
  17            ethX
  18      ab:cd:ef:ab:cd:ef
  19
  20 For packets going through IP forwarding to eth0.100 whose destination
  21 MAC address is ab:cd:ef:ab:cd:ef, dev_fill_forward_path() provides the
  22 following path:
  23
  24         eth0.100 -> eth0
  25
  26 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
  27 ---
  28
  29 --- a/include/linux/netdevice.h
  30 +++ b/include/linux/netdevice.h
  31 @@ -829,11 +829,18 @@ typedef u16 (*select_queue_fallback_t)(s
  32
  33  enum net_device_path_type {
  34         DEV_PATH_ETHERNET = 0,
  35 +       DEV_PATH_VLAN,
  36  };
  37
  38  struct net_device_path {
  39         enum net_device_path_type       type;
  40         const struct net_device         *dev;
  41 +       union {
  42 +               struct {
  43 +                       u16             id;
  44 +                       __be16          proto;
  45 +               } encap;
  46 +       };
  47  };
  48
  49  #define NET_DEVICE_PATH_STACK_MAX      5
  50 --- a/net/8021q/vlan_dev.c
  51 +++ b/net/8021q/vlan_dev.c
  52 @@ -770,6 +770,20 @@ static int vlan_dev_get_iflink(const str
  53         return real_dev->ifindex;
  54  }
  55
  56 +static int vlan_dev_fill_forward_path(struct net_device_path_ctx *ctx,
  57 +                                     struct net_device_path *path)
  58 +{
  59 +       struct vlan_dev_priv *vlan = vlan_dev_priv(ctx->dev);
  60 +
  61 +       path->type = DEV_PATH_VLAN;
  62 +       path->encap.id = vlan->vlan_id;
  63 +       path->encap.proto = vlan->vlan_proto;
  64 +       path->dev = ctx->dev;
  65 +       ctx->dev = vlan->real_dev;
  66 +
  67 +       return 0;
  68 +}
  69 +
  70  static const struct ethtool_ops vlan_ethtool_ops = {
  71         .get_link_ksettings     = vlan_ethtool_get_link_ksettings,
  72         .get_drvinfo            = vlan_ethtool_get_drvinfo,
  73 @@ -808,6 +822,7 @@ static const struct net_device_ops vlan_
  74  #endif
  75         .ndo_fix_features       = vlan_dev_fix_features,
  76         .ndo_get_iflink         = vlan_dev_get_iflink,
  77 +       .ndo_fill_forward_path  = vlan_dev_fill_forward_path,
  78  };
  79
  80  static void vlan_dev_free(struct net_device *dev)