kernel: Copy patches from kernel 4.14 to 4.19

This just copies the files from the kernel 4.14 specific folders into
the kernel 4.19 specific folder, no changes are done to the files in
this commit.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 132 insertions, 0 deletions

diff --git a/target/linux/generic/backport-4.19/292-v4.16-netfilter-core-free-hooks-with-call_rcu.patch b/target/linux/generic/backport-4.19/292-v4.16-netfilter-core-free-hooks-with-call_rcu.patch
new file mode 100644
index 0000000000..5eca73552b
--- /dev/null
+++ b/target/linux/generic/backport-4.19/292-v4.16-netfilter-core-free-hooks-with-call_rcu.patch
@@ -0,0 +1,132 @@
+From 8c873e2199700c2de7dbd5eedb9d90d5f109462b Mon Sep 17 00:00:00 2001
+From: Florian Westphal <fw@strlen.de>
+Date: Fri, 1 Dec 2017 00:21:04 +0100
+Subject: [PATCH 04/11] netfilter: core: free hooks with call_rcu
+
+Giuseppe Scrivano says:
+  "SELinux, if enabled, registers for each new network namespace 6
+    netfilter hooks."
+
+Cost for this is high.  With synchronize_net() removed:
+   "The net benefit on an SMP machine with two cores is that creating a
+   new network namespace takes -40% of the original time."
+
+This patch replaces synchronize_net+kvfree with call_rcu().
+We store rcu_head at the tail of a structure that has no fixed layout,
+i.e. we cannot use offsetof() to compute the start of the original
+allocation.  Thus store this information right after the rcu head.
+
+We could simplify this by just placing the rcu_head at the start
+of struct nf_hook_entries.  However, this structure is used in
+packet processing hotpath, so only place what is needed for that
+at the beginning of the struct.
+
+Reported-by: Giuseppe Scrivano <gscrivan@redhat.com>
+Signed-off-by: Florian Westphal <fw@strlen.de>
+Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
+---
+ include/linux/netfilter.h | 19 +++++++++++++++----
+ net/netfilter/core.c      | 34 ++++++++++++++++++++++++++++------
+ 2 files changed, 43 insertions(+), 10 deletions(-)
+
+--- a/include/linux/netfilter.h
++++ b/include/linux/netfilter.h
+@@ -77,17 +77,28 @@ struct nf_hook_entry {
+ 	void				*priv;
+ };
+ 
++struct nf_hook_entries_rcu_head {
++	struct rcu_head head;
++	void	*allocation;
++};
++
+ struct nf_hook_entries {
+ 	u16				num_hook_entries;
+ 	/* padding */
+ 	struct nf_hook_entry		hooks[];
+ 
+-	/* trailer: pointers to original orig_ops of each hook.
+-	 *
+-	 * This is not part of struct nf_hook_entry since its only
+-	 * needed in slow path (hook register/unregister).
++	/* trailer: pointers to original orig_ops of each hook,
++	 * followed by rcu_head and scratch space used for freeing
++	 * the structure via call_rcu.
+ 	 *
++	 *   This is not part of struct nf_hook_entry since its only
++	 *   needed in slow path (hook register/unregister):
+ 	 * const struct nf_hook_ops     *orig_ops[]
++	 *
++	 *   For the same reason, we store this at end -- its
++	 *   only needed when a hook is deleted, not during
++	 *   packet path processing:
++	 * struct nf_hook_entries_rcu_head     head
+ 	 */
+ };
+ 
+--- a/net/netfilter/core.c
++++ b/net/netfilter/core.c
+@@ -74,7 +74,8 @@ static struct nf_hook_entries *allocate_
+ 	struct nf_hook_entries *e;
+ 	size_t alloc = sizeof(*e) +
+ 		       sizeof(struct nf_hook_entry) * num +
+-		       sizeof(struct nf_hook_ops *) * num;
++		       sizeof(struct nf_hook_ops *) * num +
++		       sizeof(struct nf_hook_entries_rcu_head);
+ 
+ 	if (num == 0)
+ 		return NULL;
+@@ -85,6 +86,30 @@ static struct nf_hook_entries *allocate_
+ 	return e;
+ }
+ 
++static void __nf_hook_entries_free(struct rcu_head *h)
++{
++	struct nf_hook_entries_rcu_head *head;
++
++	head = container_of(h, struct nf_hook_entries_rcu_head, head);
++	kvfree(head->allocation);
++}
++
++static void nf_hook_entries_free(struct nf_hook_entries *e)
++{
++	struct nf_hook_entries_rcu_head *head;
++	struct nf_hook_ops **ops;
++	unsigned int num;
++
++	if (!e)
++		return;
++
++	num = e->num_hook_entries;
++	ops = nf_hook_entries_get_hook_ops(e);
++	head = (void *)&ops[num];
++	head->allocation = e;
++	call_rcu(&head->head, __nf_hook_entries_free);
++}
++
+ static unsigned int accept_all(void *priv,
+ 			       struct sk_buff *skb,
+ 			       const struct nf_hook_state *state)
+@@ -291,9 +316,8 @@ int nf_register_net_hook(struct net *net
+ #ifdef HAVE_JUMP_LABEL
+ 	static_key_slow_inc(&nf_hooks_needed[reg->pf][reg->hooknum]);
+ #endif
+-	synchronize_net();
+ 	BUG_ON(p == new_hooks);
+-	kvfree(p);
++	nf_hook_entries_free(p);
+ 	return 0;
+ }
+ EXPORT_SYMBOL(nf_register_net_hook);
+@@ -361,10 +385,8 @@ void nf_unregister_net_hook(struct net *
+ 	if (!p)
+ 		return;
+ 
+-	synchronize_net();
+-
+ 	nf_queue_nf_hook_drop(net);
+-	kvfree(p);
++	nf_hook_entries_free(p);
+ }
+ EXPORT_SYMBOL(nf_unregister_net_hook);
+