From fc7aa4b30acf126bd4e8d0aeee21e6d772072b28 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 4 Sep 2026 12:14:10 -0700 Subject: [PATCH 1/3] netlink: specs: fou: add af to the shared attribute list parse_nl_config() is the only place the address family is chosen: it defaults cfg->udp_config.family to AF_INET and only switches to AF_INET6 when FOU_ATTR_AF is present. The &all_attrs anchor - the add request, and the get do and dump reply - does not list af, so a ynl generated client has no fou_add_req_set_af() and can never create an IPv6 FOU port; the local-v6 / peer-v6 attributes it does list are read by nothing. On the reply side fou_fill_info() puts FOU_ATTR_AF unconditionally, and struct fou_get_rsp has no member for it. kernel-policy is global, so fou_nl_ops[] carries no per-op attribute list and af is already in fou_nl_policy through &select_attrs - only the user space codegen and the rendered docs change, ynl-regen.sh produces no diff. Signed-off-by: Jakub Kicinski Reviewed-by: Nicolas Dichtel Link: https://patch.msgid.link/20260904191412.3872344-2-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/netlink/specs/fou.yaml | 1 + 1 file changed, 1 insertion(+) diff --git a/Documentation/netlink/specs/fou.yaml b/Documentation/netlink/specs/fou.yaml index 331f1b342b3a..32d34be1dc63 100644 --- a/Documentation/netlink/specs/fou.yaml +++ b/Documentation/netlink/specs/fou.yaml @@ -90,6 +90,7 @@ operations: request: &all_attrs attributes: - port + - af - ipproto - type - remcsum-nopartial From 3f4285d741b4017a3f36cc4cfa272d0343b60a5d Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 4 Sep 2026 12:14:11 -0700 Subject: [PATCH 2/3] netlink: specs: fou: local-v4 and peer-v4 are big endian fou_core.c uses nla_get_in_addr() / nla_put_in_addr() on both, i.e. they are __be32, and port / peer-port in the same spec are already annotated. Without byte-order YNL swaps them on little endian hosts. The generated policy goes from NLA_U32 to NLA_BE32, which changes nothing: lib/nlattr.c gives the two the same length in nla_attr_len[] and the same range handling, and neither attribute has a range check. Signed-off-by: Jakub Kicinski Reviewed-by: Nicolas Dichtel Link: https://patch.msgid.link/20260904191412.3872344-3-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/netlink/specs/fou.yaml | 2 ++ net/ipv4/fou_nl.c | 4 ++-- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/Documentation/netlink/specs/fou.yaml b/Documentation/netlink/specs/fou.yaml index 32d34be1dc63..1d0db6ba7e52 100644 --- a/Documentation/netlink/specs/fou.yaml +++ b/Documentation/netlink/specs/fou.yaml @@ -50,6 +50,7 @@ attribute-sets: - name: local-v4 type: u32 + byte-order: big-endian - name: local-v6 type: binary @@ -58,6 +59,7 @@ attribute-sets: - name: peer-v4 type: u32 + byte-order: big-endian - name: peer-v6 type: binary diff --git a/net/ipv4/fou_nl.c b/net/ipv4/fou_nl.c index 309d5ba983d0..cdb174b92cdd 100644 --- a/net/ipv4/fou_nl.c +++ b/net/ipv4/fou_nl.c @@ -18,9 +18,9 @@ const struct nla_policy fou_nl_policy[FOU_ATTR_IFINDEX + 1] = { [FOU_ATTR_IPPROTO] = NLA_POLICY_MIN(NLA_U8, 1), [FOU_ATTR_TYPE] = { .type = NLA_U8, }, [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, }, - [FOU_ATTR_LOCAL_V4] = { .type = NLA_U32, }, + [FOU_ATTR_LOCAL_V4] = { .type = NLA_BE32, }, [FOU_ATTR_LOCAL_V6] = NLA_POLICY_EXACT_LEN(16), - [FOU_ATTR_PEER_V4] = { .type = NLA_U32, }, + [FOU_ATTR_PEER_V4] = { .type = NLA_BE32, }, [FOU_ATTR_PEER_V6] = NLA_POLICY_EXACT_LEN(16), [FOU_ATTR_PEER_PORT] = { .type = NLA_BE16, }, [FOU_ATTR_IFINDEX] = { .type = NLA_S32, }, From 1859a0cc3adbc4ed2cb2dfe1cdb3bbc96b5d2cab Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 4 Sep 2026 12:14:12 -0700 Subject: [PATCH 3/3] netlink: specs: fou: link the type attribute to the encap-type enum The spec defines encap-type (unspec / direct / gue), but no attribute references it, so the definition exists only to emit FOU_ENCAP_* into the uAPI header - while FOU_ATTR_TYPE is exactly that value space: fou_create() switches on FOU_ENCAP_DIRECT / FOU_ENCAP_GUE and returns -EINVAL for anything else. Python YNL could not accept or display the names and the generated C exposed a raw __u8 setter. The global policy entry becomes NLA_POLICY_MAX(NLA_U8, 2). For add that only moves the existing fou_create() rejection earlier; del and get ignore FOU_ATTR_TYPE altogether, so a bogus type there now fails validation instead of being dropped on the floor. Signed-off-by: Jakub Kicinski Reviewed-by: Nicolas Dichtel Link: https://patch.msgid.link/20260904191412.3872344-4-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/netlink/specs/fou.yaml | 1 + net/ipv4/fou_nl.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/netlink/specs/fou.yaml b/Documentation/netlink/specs/fou.yaml index 1d0db6ba7e52..3e6a38e31202 100644 --- a/Documentation/netlink/specs/fou.yaml +++ b/Documentation/netlink/specs/fou.yaml @@ -44,6 +44,7 @@ attribute-sets: - name: type type: u8 + enum: encap-type - name: remcsum-nopartial type: flag diff --git a/net/ipv4/fou_nl.c b/net/ipv4/fou_nl.c index cdb174b92cdd..ccd134ba352d 100644 --- a/net/ipv4/fou_nl.c +++ b/net/ipv4/fou_nl.c @@ -16,7 +16,7 @@ const struct nla_policy fou_nl_policy[FOU_ATTR_IFINDEX + 1] = { [FOU_ATTR_PORT] = { .type = NLA_BE16, }, [FOU_ATTR_AF] = { .type = NLA_U8, }, [FOU_ATTR_IPPROTO] = NLA_POLICY_MIN(NLA_U8, 1), - [FOU_ATTR_TYPE] = { .type = NLA_U8, }, + [FOU_ATTR_TYPE] = NLA_POLICY_MAX(NLA_U8, 2), [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, }, [FOU_ATTR_LOCAL_V4] = { .type = NLA_BE32, }, [FOU_ATTR_LOCAL_V6] = NLA_POLICY_EXACT_LEN(16),