target/linux/generic/pending-5.15/704-01-netfilter-nft_flow_offload-skip-dst-neigh-lookup-for.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Fri, 6 May 2022 12:43:58 +0200
   3 Subject: [PATCH] netfilter: nft_flow_offload: skip dst neigh lookup for
   4  ppp devices
   5
   6 The dst entry does not contain a valid hardware address, so skip the lookup
   7 in order to avoid running into errors here.
   8 The proper hardware address is filled in from nft_dev_path_info
   9
  10 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  11 ---
  12
  13 --- a/net/netfilter/nft_flow_offload.c
  14 +++ b/net/netfilter/nft_flow_offload.c
  15 @@ -36,6 +36,15 @@ static void nft_default_forward_path(str
  16         route->tuple[dir].xmit_type     = nft_xmit_type(dst_cache);
  17  }
  18
  19 +static bool nft_is_valid_ether_device(const struct net_device *dev)
  20 +{
  21 +       if (!dev || (dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER ||
  22 +           dev->addr_len != ETH_ALEN || !is_valid_ether_addr(dev->dev_addr))
  23 +               return false;
  24 +
  25 +       return true;
  26 +}
  27 +
  28  static int nft_dev_fill_forward_path(const struct nf_flow_route *route,
  29                                      const struct dst_entry *dst_cache,
  30                                      const struct nf_conn *ct,
  31 @@ -47,6 +56,9 @@ static int nft_dev_fill_forward_path(con
  32         struct neighbour *n;
  33         u8 nud_state;
  34
  35 +       if (!nft_is_valid_ether_device(dev))
  36 +               goto out;
  37 +
  38         n = dst_neigh_lookup(dst_cache, daddr);
  39         if (!n)
  40                 return -1;
  41 @@ -60,6 +72,7 @@ static int nft_dev_fill_forward_path(con
  42         if (!(nud_state & NUD_VALID))
  43                 return -1;
  44
  45 +out:
  46         return dev_fill_forward_path(dev, ha, stack);
  47  }
  48
  49 @@ -78,15 +91,6 @@ struct nft_forward_info {
  50         enum flow_offload_xmit_type xmit_type;
  51  };
  52
  53 -static bool nft_is_valid_ether_device(const struct net_device *dev)
  54 -{
  55 -       if (!dev || (dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER ||
  56 -           dev->addr_len != ETH_ALEN || !is_valid_ether_addr(dev->dev_addr))
  57 -               return false;
  58 -
  59 -       return true;
  60 -}
  61 -
  62  static void nft_dev_path_info(const struct net_device_path_stack *stack,
  63                               struct nft_forward_info *info,
  64                               unsigned char *ha, struct nf_flowtable *flowtable)