net: Copy inner L3 and L4 headers as unaligned on GRE TEB

This patch corrects the unaligned accesses seen on GRE TEB tunnels when
generating hash keys.  Specifically what this patch does is make it so that
we force the use of skb_copy_bits when the GRE inner headers will be
unaligned due to NET_IP_ALIGNED being a non-zero value.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index eab81bc80e5cdff993a030b109cbffa133262bf0..12e7003320107dbb2b86f4fa1cfd20a8d59e8ed5 100644 (file)
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -399,6 +399,13 @@ ip_proto_again:
                                goto out_bad;
                        proto = eth->h_proto;
                        nhoff += sizeof(*eth);
+
+                       /* Cap headers that we access via pointers at the
+                        * end of the Ethernet header as our maximum alignment
+                        * at that point is only 2 bytes.
+                        */
+                       if (NET_IP_ALIGN)
+                               hlen = nhoff;
                }
 
                key_control->flags |= FLOW_DIS_ENCAPSULATION;