kernel: generic: Fix nftables inet table breakage

Commit b7265c59ab7d ("kernel: backport a series of netfilter cleanup
patches to 4.14") added patch 302-netfilter-nf_tables_inet-don-t-use-
multihook-infrast.patch.  That patch switches the netfilter core in the
kernel to use the new native NFPROTO_INET support.  Unfortunately, the
new native NFPROTO_INET support does not exist in 4.14 and was not
backported along with this patchset.  As such, nftables inet tables never
see any traffic.

As an example the following nft counter rule should increment for every
packet coming into the box, but never will:

nft add table inet foo
nft add chain inet foo bar { type filter hook input priority 0\; }
nft add rule inet foo bar counter

This commit pulls in the required backport patches to add the new
native NFPROTO_INET support, and thus restore nftables inet table
functionality.

Tested on Turris Omnia (mvebu)

Fixes: b7265c59ab7d ("kernel: backport a series of netfilter cleanup ...")
Signed-off-by: Brett Mastbergen <bmastbergen@untangle.com>
(backported from f57806b56e5f6ca7bb9fb66d5b175b5f98ece93c)
(rebased patches)
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 44 insertions, 0 deletions

diff --git a/target/linux/generic/backport-4.14/298-v4.16-netfilter-core-add-nf_remove_net_hook.patch b/target/linux/generic/backport-4.14/298-v4.16-netfilter-core-add-nf_remove_net_hook.patch
new file mode 100644
index 0000000000..8fea44b359
--- /dev/null
+++ b/target/linux/generic/backport-4.14/298-v4.16-netfilter-core-add-nf_remove_net_hook.patch
@@ -0,0 +1,44 @@
+From 3d3cdc38e8c265a9f9d3825e823e772872bca1b8 Mon Sep 17 00:00:00 2001
+From: Pablo Neira Ayuso <pablo@netfilter.org>
+Date: Sat, 9 Dec 2017 15:19:14 +0100
+Subject: [PATCH 01/11] netfilter: core: add nf_remove_net_hook
+
+Just a cleanup, __nf_unregister_net_hook() is used by a follow up patch
+when handling NFPROTO_INET as a real family from the core.
+
+Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
+---
+ net/netfilter/core.c | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+--- a/net/netfilter/core.c
++++ b/net/netfilter/core.c
+@@ -356,7 +356,7 @@ int nf_register_net_hook(struct net *net
+ EXPORT_SYMBOL(nf_register_net_hook);
+ 
+ /*
+- * __nf_unregister_net_hook - remove a hook from blob
++ * nf_remove_net_hook - remove a hook from blob
+  *
+  * @oldp: current address of hook blob
+  * @unreg: hook to unregister
+@@ -364,8 +364,8 @@ EXPORT_SYMBOL(nf_register_net_hook);
+  * This cannot fail, hook unregistration must always succeed.
+  * Therefore replace the to-be-removed hook with a dummy hook.
+  */
+-static void __nf_unregister_net_hook(struct nf_hook_entries *old,
+-				     const struct nf_hook_ops *unreg)
++static void nf_remove_net_hook(struct nf_hook_entries *old,
++			       const struct nf_hook_ops *unreg)
+ {
+ 	struct nf_hook_ops **orig_ops;
+ 	bool found = false;
+@@ -411,7 +411,7 @@ void nf_unregister_net_hook(struct net *
+ 		return;
+ 	}
+ 
+-	__nf_unregister_net_hook(p, reg);
++	nf_remove_net_hook(p, reg);
+ 
+ 	p = __nf_hook_entries_try_shrink(pp);
+ 	mutex_unlock(&nf_hook_mutex);