ethtool: add and use message type for tunnel info reply

Tunnel offload info code uses ETHTOOL_MSG_TUNNEL_INFO_GET message type (cmd
field in genetlink header) for replies to tunnel info netlink request, i.e.
the same value as the request have. This is a problem because we are using
two separate enums for userspace to kernel and kernel to userspace message
types so that this ETHTOOL_MSG_TUNNEL_INFO_GET (28) collides with
ETHTOOL_MSG_CABLE_TEST_TDR_NTF which is what message type 28 means for
kernel to userspace messages.

As the tunnel info request reached mainline in 5.9 merge window, we should
still be able to fix the reply message type without breaking backward
compatibility.

Fixes: c7d759eb7b12 ("ethtool: add tunnel info interface")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index d53bcb31645a4707ed9fd0bacaf912481097f7d6..b5a79881551f87c82b458f9061eafe5de318ca41 100644 (file)
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -206,6 +206,7 @@ Userspace to kernel:
   ``ETHTOOL_MSG_TSINFO_GET``           get timestamping info
   ``ETHTOOL_MSG_CABLE_TEST_ACT``        action start cable test
   ``ETHTOOL_MSG_CABLE_TEST_TDR_ACT``    action start raw TDR cable test
+  ``ETHTOOL_MSG_TUNNEL_INFO_GET``       get tunnel offload info
   ===================================== ================================
 
 Kernel to userspace:
@@ -239,6 +240,7 @@ Kernel to userspace:
   ``ETHTOOL_MSG_TSINFO_GET_REPLY``     timestamping info
   ``ETHTOOL_MSG_CABLE_TEST_NTF``        Cable test results
   ``ETHTOOL_MSG_CABLE_TEST_TDR_NTF``    Cable test TDR results
+  ``ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY`` tunnel offload info
   ===================================== =================================
 
 ``GET`` requests are sent by userspace applications to retrieve device
@@ -1363,4 +1365,5 @@ are netlink only.
   ``ETHTOOL_SFECPARAM``               n/a
   n/a                                 ''ETHTOOL_MSG_CABLE_TEST_ACT''
   n/a                                 ''ETHTOOL_MSG_CABLE_TEST_TDR_ACT''
+  n/a                                 ``ETHTOOL_MSG_TUNNEL_INFO_GET``
   =================================== =====================================

diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 5dcd24cb33ea2d6ea69829e6c7ca22d320b1fc77..72ba36be96550bf537fee86b6eecd19a46dc8460 100644 (file)
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -79,6 +79,7 @@ enum {
        ETHTOOL_MSG_TSINFO_GET_REPLY,
        ETHTOOL_MSG_CABLE_TEST_NTF,
        ETHTOOL_MSG_CABLE_TEST_TDR_NTF,
+       ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY,
 
        /* add new constants above here */
        __ETHTOOL_MSG_KERNEL_CNT,

diff --git a/net/ethtool/tunnels.c b/net/ethtool/tunnels.c
index 84f23289475bcb9cacf8db38dbdf372c904d1af2..d93bf2da0f34736be0574c1ff1c9f896d946f832 100644 (file)
--- a/net/ethtool/tunnels.c
+++ b/net/ethtool/tunnels.c
@@ -200,7 +200,7 @@ int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info)
        reply_len = ret + ethnl_reply_header_size();
 
        rskb = ethnl_reply_init(reply_len, req_info.dev,
-                               ETHTOOL_MSG_TUNNEL_INFO_GET,
+                               ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY,
                                ETHTOOL_A_TUNNEL_INFO_HEADER,
                                info, &reply_payload);
        if (!rskb) {
@@ -273,7 +273,7 @@ int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
                                goto cont;
 
                        ehdr = ethnl_dump_put(skb, cb,
-                                             ETHTOOL_MSG_TUNNEL_INFO_GET);
+                                             ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY);
                        if (!ehdr) {
                                ret = -EMSGSIZE;
                                goto out;