target/linux/generic/backport-4.19/296-v4.16-netfilter-don-t-allocate-space-for-arp-bridge-hooks-.patch

   1 From 2a95183a5e0375df756efb2ca37602d71e8455f9 Mon Sep 17 00:00:00 2001
   2 From: Florian Westphal <fw@strlen.de>
   3 Date: Thu, 7 Dec 2017 16:28:26 +0100
   4 Subject: [PATCH 08/11] netfilter: don't allocate space for arp/bridge hooks
   5  unless needed
   6
   7 no need to define hook points if the family isn't supported.
   8 Because we need these hooks for either nftables, arp/ebtables
   9 or the 'call-iptables' hack we have in the bridge layer add two
  10 new dependencies, NETFILTER_FAMILY_{ARP,BRIDGE}, and have the
  11 users select them.
  12
  13 Signed-off-by: Florian Westphal <fw@strlen.de>
  14 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
  15 ---
  16  include/linux/netfilter.h     | 4 ++++
  17  include/net/netns/netfilter.h | 4 ++++
  18  net/Kconfig                   | 1 +
  19  net/bridge/netfilter/Kconfig  | 2 ++
  20  net/ipv4/netfilter/Kconfig    | 2 ++
  21  net/netfilter/Kconfig         | 6 ++++++
  22  net/netfilter/core.c          | 8 ++++++++
  23  net/netfilter/nf_queue.c      | 2 ++
  24  8 files changed, 29 insertions(+)
  25
  26 --- a/include/linux/netfilter.h
  27 +++ b/include/linux/netfilter.h
  28 @@ -214,10 +214,14 @@ static inline int nf_hook(u_int8_t pf, u
  29                 hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
  30                 break;
  31         case NFPROTO_ARP:
  32 +#ifdef CONFIG_NETFILTER_FAMILY_ARP
  33                 hook_head = rcu_dereference(net->nf.hooks_arp[hook]);
  34 +#endif
  35                 break;
  36         case NFPROTO_BRIDGE:
  37 +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
  38                 hook_head = rcu_dereference(net->nf.hooks_bridge[hook]);
  39 +#endif
  40                 break;
  41  #if IS_ENABLED(CONFIG_DECNET)
  42         case NFPROTO_DECNET:
  43 --- a/include/net/netns/netfilter.h
  44 +++ b/include/net/netns/netfilter.h
  45 @@ -19,8 +19,12 @@ struct netns_nf {
  46  #endif
  47         struct nf_hook_entries __rcu *hooks_ipv4[NF_INET_NUMHOOKS];
  48         struct nf_hook_entries __rcu *hooks_ipv6[NF_INET_NUMHOOKS];
  49 +#ifdef CONFIG_NETFILTER_FAMILY_ARP
  50         struct nf_hook_entries __rcu *hooks_arp[NF_ARP_NUMHOOKS];
  51 +#endif
  52 +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
  53         struct nf_hook_entries __rcu *hooks_bridge[NF_INET_NUMHOOKS];
  54 +#endif
  55  #if IS_ENABLED(CONFIG_DECNET)
  56         struct nf_hook_entries __rcu *hooks_decnet[NF_DN_NUMHOOKS];
  57  #endif
  58 --- a/net/Kconfig
  59 +++ b/net/Kconfig
  60 @@ -182,6 +182,7 @@ config BRIDGE_NETFILTER
  61         depends on BRIDGE
  62         depends on NETFILTER && INET
  63         depends on NETFILTER_ADVANCED
  64 +       select NETFILTER_FAMILY_BRIDGE
  65         default m
  66         ---help---
  67           Enabling this option will let arptables resp. iptables see bridged
  68 --- a/net/bridge/netfilter/Kconfig
  69 +++ b/net/bridge/netfilter/Kconfig
  70 @@ -4,6 +4,7 @@
  71  #
  72  menuconfig NF_TABLES_BRIDGE
  73         depends on BRIDGE && NETFILTER && NF_TABLES
  74 +       select NETFILTER_FAMILY_BRIDGE
  75         tristate "Ethernet Bridge nf_tables support"
  76
  77  if NF_TABLES_BRIDGE
  78 @@ -29,6 +30,7 @@ endif # NF_TABLES_BRIDGE
  79  menuconfig BRIDGE_NF_EBTABLES
  80         tristate "Ethernet Bridge tables (ebtables) support"
  81         depends on BRIDGE && NETFILTER && NETFILTER_XTABLES
  82 +       select NETFILTER_FAMILY_BRIDGE
  83         help
  84           ebtables is a general, extensible frame/packet identification
  85           framework. Say 'Y' or 'M' here if you want to do Ethernet
  86 --- a/net/ipv4/netfilter/Kconfig
  87 +++ b/net/ipv4/netfilter/Kconfig
  88 @@ -72,6 +72,7 @@ endif # NF_TABLES_IPV4
  89
  90  config NF_TABLES_ARP
  91         tristate "ARP nf_tables support"
  92 +       select NETFILTER_FAMILY_ARP
  93         help
  94           This option enables the ARP support for nf_tables.
  95
  96 @@ -392,6 +393,7 @@ endif # IP_NF_IPTABLES
  97  config IP_NF_ARPTABLES
  98         tristate "ARP tables support"
  99         select NETFILTER_XTABLES
 100 +       select NETFILTER_FAMILY_ARP
 101         depends on NETFILTER_ADVANCED
 102         help
 103           arptables is a general, extensible packet identification framework.
 104 --- a/net/netfilter/Kconfig
 105 +++ b/net/netfilter/Kconfig
 106 @@ -12,6 +12,12 @@ config NETFILTER_INGRESS
 107  config NETFILTER_NETLINK
 108         tristate
 109
 110 +config NETFILTER_FAMILY_BRIDGE
 111 +       bool
 112 +
 113 +config NETFILTER_FAMILY_ARP
 114 +       bool
 115 +
 116  config NETFILTER_NETLINK_ACCT
 117  tristate "Netfilter NFACCT over NFNETLINK interface"
 118         depends on NETFILTER_ADVANCED
 119 --- a/net/netfilter/core.c
 120 +++ b/net/netfilter/core.c
 121 @@ -267,14 +267,18 @@ static struct nf_hook_entries __rcu **nf
 122         switch (reg->pf) {
 123         case NFPROTO_NETDEV:
 124                 break;
 125 +#ifdef CONFIG_NETFILTER_FAMILY_ARP
 126         case NFPROTO_ARP:
 127                 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_arp) <= reg->hooknum))
 128                         return NULL;
 129                 return net->nf.hooks_arp + reg->hooknum;
 130 +#endif
 131 +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
 132         case NFPROTO_BRIDGE:
 133                 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_bridge) <= reg->hooknum))
 134                         return NULL;
 135                 return net->nf.hooks_bridge + reg->hooknum;
 136 +#endif
 137         case NFPROTO_IPV4:
 138                 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_ipv4) <= reg->hooknum))
 139                         return NULL;
 140 @@ -573,8 +577,12 @@ static int __net_init netfilter_net_init
 141  {
 142         __netfilter_net_init(net->nf.hooks_ipv4, ARRAY_SIZE(net->nf.hooks_ipv4));
 143         __netfilter_net_init(net->nf.hooks_ipv6, ARRAY_SIZE(net->nf.hooks_ipv6));
 144 +#ifdef CONFIG_NETFILTER_FAMILY_ARP
 145         __netfilter_net_init(net->nf.hooks_arp, ARRAY_SIZE(net->nf.hooks_arp));
 146 +#endif
 147 +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
 148         __netfilter_net_init(net->nf.hooks_bridge, ARRAY_SIZE(net->nf.hooks_bridge));
 149 +#endif
 150  #if IS_ENABLED(CONFIG_DECNET)
 151         __netfilter_net_init(net->nf.hooks_decnet, ARRAY_SIZE(net->nf.hooks_decnet));
 152  #endif
 153 --- a/net/netfilter/nf_queue.c
 154 +++ b/net/netfilter/nf_queue.c
 155 @@ -204,8 +204,10 @@ repeat:
 156  static struct nf_hook_entries *nf_hook_entries_head(const struct net *net, u8 pf, u8 hooknum)
 157  {
 158         switch (pf) {
 159 +#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
 160         case NFPROTO_BRIDGE:
 161                 return rcu_dereference(net->nf.hooks_bridge[hooknum]);
 162 +#endif
 163         case NFPROTO_IPV4:
 164                 return rcu_dereference(net->nf.hooks_ipv4[hooknum]);
 165         case NFPROTO_IPV6: