Patch "net: change skb->mac_header when Generic XDP calls adjust_head" has been added to the 4.13-stable tree

Patch "net: change skb->mac_header when Generic XDP calls adjust_head" has been added to the 4.13-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    net: change skb->mac_header when Generic XDP calls adjust_head

to the 4.13-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-change-skb-mac_header-when-generic-xdp-calls-adjust_head.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Oct  9 09:32:35 CEST 2017
From: Edward Cree <ecree@solarflare.com>
Date: Tue, 19 Sep 2017 18:45:56 +0100
Subject: net: change skb->mac_header when Generic XDP calls adjust_head

From: Edward Cree <ecree@solarflare.com>


[ Upstream commit 92dd5452c1be873a1193561f4f691763103d22ac ]

Since XDP's view of the packet includes the MAC header, moving the start-
 of-packet with bpf_xdp_adjust_head needs to also update the offset of the
 MAC header (which is relative to skb->head, not to the skb->data that was
 changed).
Without this, tcpdump sees packets starting from the old MAC header rather
 than the new one, at least in my tests on the loopback device.

Fixes: b5cdae3291f7 ("net: Generic XDP")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/core/dev.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4408,6 +4408,7 @@ static u32 netif_receive_generic_xdp(str
 		__skb_pull(skb, off);
 	else if (off < 0)
 		__skb_push(skb, -off);
+	skb->mac_header += off;
 
 	switch (act) {
 	case XDP_TX:


Patches currently in stable-queue which might be from ecree@solarflare.com are

queue-4.13/net-change-skb-mac_header-when-generic-xdp-calls-adjust_head.patch
queue-4.13/bpf-verifier-reject-bpf_alu64-bpf_end.patch