brcm2708: update linux 4.4 patches to latest version

As usual these patches were extracted and rebased from the raspberry pi repo:
https://github.com/raspberrypi/linux/tree/rpi-4.4.y

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 97 insertions, 0 deletions

diff --git a/target/linux/brcm2708/patches-4.4/0221-bpf-add-skb_postpush_rcsum-and-fix-dev_forward_skb-o.patch b/target/linux/brcm2708/patches-4.4/0221-bpf-add-skb_postpush_rcsum-and-fix-dev_forward_skb-o.patch
new file mode 100644
index 0000000000..f6622d5bd0
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.4/0221-bpf-add-skb_postpush_rcsum-and-fix-dev_forward_skb-o.patch
@@ -0,0 +1,97 @@
+From 367956e87b62ae1f015ccbff58c7920a2e7a3511 Mon Sep 17 00:00:00 2001
+From: Daniel Borkmann <daniel@iogearbox.net>
+Date: Thu, 7 Jan 2016 15:50:23 +0100
+Subject: [PATCH 221/423] bpf: add skb_postpush_rcsum and fix dev_forward_skb
+ occasions
+
+Add a small helper skb_postpush_rcsum() and fix up redirect locations
+that need CHECKSUM_COMPLETE fixups on ingress. dev_forward_skb() expects
+a proper csum that covers also Ethernet header, f.e. since 2c26d34bbcc0
+("net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding"), we
+also do skb_postpull_rcsum() after pulling Ethernet header off via
+eth_type_trans().
+
+When using eBPF in a netns setup f.e. with vxlan in collect metadata mode,
+I can trigger the following csum issue with an IPv6 setup:
+
+  [  505.144065] dummy1: hw csum failure
+  [...]
+  [  505.144108] Call Trace:
+  [  505.144112]  <IRQ>  [<ffffffff81372f08>] dump_stack+0x44/0x5c
+  [  505.144134]  [<ffffffff81607cea>] netdev_rx_csum_fault+0x3a/0x40
+  [  505.144142]  [<ffffffff815fee3f>] __skb_checksum_complete+0xcf/0xe0
+  [  505.144149]  [<ffffffff816f0902>] nf_ip6_checksum+0xb2/0x120
+  [  505.144161]  [<ffffffffa08c0e0e>] icmpv6_error+0x17e/0x328 [nf_conntrack_ipv6]
+  [  505.144170]  [<ffffffffa0898eca>] ? ip6t_do_table+0x2fa/0x645 [ip6_tables]
+  [  505.144177]  [<ffffffffa08c0725>] ? ipv6_get_l4proto+0x65/0xd0 [nf_conntrack_ipv6]
+  [  505.144189]  [<ffffffffa06c9a12>] nf_conntrack_in+0xc2/0x5a0 [nf_conntrack]
+  [  505.144196]  [<ffffffffa08c039c>] ipv6_conntrack_in+0x1c/0x20 [nf_conntrack_ipv6]
+  [  505.144204]  [<ffffffff8164385d>] nf_iterate+0x5d/0x70
+  [  505.144210]  [<ffffffff816438d6>] nf_hook_slow+0x66/0xc0
+  [  505.144218]  [<ffffffff816bd302>] ipv6_rcv+0x3f2/0x4f0
+  [  505.144225]  [<ffffffff816bca40>] ? ip6_make_skb+0x1b0/0x1b0
+  [  505.144232]  [<ffffffff8160b77b>] __netif_receive_skb_core+0x36b/0x9a0
+  [  505.144239]  [<ffffffff8160bdc8>] ? __netif_receive_skb+0x18/0x60
+  [  505.144245]  [<ffffffff8160bdc8>] __netif_receive_skb+0x18/0x60
+  [  505.144252]  [<ffffffff8160ccff>] process_backlog+0x9f/0x140
+  [  505.144259]  [<ffffffff8160c4a5>] net_rx_action+0x145/0x320
+  [...]
+
+What happens is that on ingress, we push Ethernet header back in, either
+from cls_bpf or right before skb_do_redirect(), but without updating csum.
+The "hw csum failure" can be fixed by using the new skb_postpush_rcsum()
+helper for the dev_forward_skb() case to correct the csum diff again.
+
+Thanks to Hannes Frederic Sowa for the csum_partial() idea!
+
+Fixes: 3896d655f4d4 ("bpf: introduce bpf_clone_redirect() helper")
+Fixes: 27b29f63058d ("bpf: add bpf_redirect() helper")
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Acked-by: Alexei Starovoitov <ast@kernel.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ net/core/filter.c | 17 +++++++++++++----
+ 1 file changed, 13 insertions(+), 4 deletions(-)
+
+--- a/net/core/filter.c
++++ b/net/core/filter.c
+@@ -1293,8 +1293,9 @@ static u64 bpf_skb_store_bytes(u64 r1, u
+ 		/* skb_store_bits cannot return -EFAULT here */
+ 		skb_store_bits(skb, offset, ptr, len);
+ 
+-	if (BPF_RECOMPUTE_CSUM(flags) && skb->ip_summed == CHECKSUM_COMPLETE)
+-		skb->csum = csum_add(skb->csum, csum_partial(ptr, len, 0));
++	if (BPF_RECOMPUTE_CSUM(flags))
++		skb_postpush_rcsum(skb, ptr, len);
++
+ 	return 0;
+ }
+ 
+@@ -1420,8 +1421,12 @@ static u64 bpf_clone_redirect(u64 r1, u6
+ 	if (unlikely(!skb2))
+ 		return -ENOMEM;
+ 
+-	if (BPF_IS_REDIRECT_INGRESS(flags))
++	if (BPF_IS_REDIRECT_INGRESS(flags)) {
++		if (skb_at_tc_ingress(skb2))
++			skb_postpush_rcsum(skb2, skb_mac_header(skb2),
++					   skb2->mac_len);
+ 		return dev_forward_skb(dev, skb2);
++	}
+ 
+ 	skb2->dev = dev;
+ 	skb_sender_cpu_clear(skb2);
+@@ -1464,8 +1469,12 @@ int skb_do_redirect(struct sk_buff *skb)
+ 		return -EINVAL;
+ 	}
+ 
+-	if (BPF_IS_REDIRECT_INGRESS(ri->flags))
++	if (BPF_IS_REDIRECT_INGRESS(ri->flags)) {
++		if (skb_at_tc_ingress(skb))
++			skb_postpush_rcsum(skb, skb_mac_header(skb),
++					   skb->mac_len);
+ 		return dev_forward_skb(dev, skb);
++	}
+ 
+ 	skb->dev = dev;
+ 	skb_sender_cpu_clear(skb);