| Message ID | f96aa9e8c08f7473fcd4b04905bb42d18088cb15.1624572003.git.gnault@redhat.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | aab1e898c26c3e4289c62b6d6482948672fab939 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: reset MAC header consistently across L3 virtual devices | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 5 of 5 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 19 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index a68bf4c6fe9b..12dca0c85f3c 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -107,6 +107,8 @@ module_param(log_ecn_error, bool, 0644); MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); static struct rtnl_link_ops ipgre_link_ops __read_mostly; +static const struct header_ops ipgre_header_ops; + static int ipgre_tunnel_init(struct net_device *dev); static void erspan_build_header(struct sk_buff *skb, u32 id, u32 index, @@ -364,7 +366,10 @@ static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, raw_proto, false) < 0) goto drop; - if (tunnel->dev->type != ARPHRD_NONE) + /* Special case for ipgre_header_parse(), which expects the + * mac_header to point to the outer IP header. + */ + if (tunnel->dev->header_ops == &ipgre_header_ops) skb_pop_mac_header(skb); else skb_reset_mac_header(skb);
Commit e271c7b4420d ("gre: do not keep the GRE header around in collect medata mode") did reset the mac_header for the collect_md case. Let's extend this behaviour to classical gre devices as well. ipgre_header_parse() seems to be the only case that requires mac_header to point to the outer header. We can detect this case accurately by checking ->header_ops. For all other cases, we can reset mac_header. This allows to push an Ethernet header to ipgre packets and redirect them to an Ethernet device: $ tc filter add dev gre0 ingress matchall \ action vlan push_eth dst_mac 00:00:5e:00:53:01 \ src_mac 00:00:5e:00:53:00 \ action mirred egress redirect dev eth0 Before this patch, this worked only for collect_md gre devices. Now this works for regular gre devices as well. Only the special case of gre devices that use ipgre_header_ops isn't supported. Signed-off-by: Guillaume Nault <gnault@redhat.com> --- net/ipv4/ip_gre.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)