netlink: introduce bigendian integer types

Jakub reported that the addition of the "network_byte_order"
member in struct nla_policy increases size of 32bit platforms.

Instead of scraping the bit from elsewhere Johannes suggested
to add explicit NLA_BE types instead, so do this here.

NLA_POLICY_MAX_BE() macro is removed again, there is no need
for it: NLA_POLICY_MAX(NLA_BE.., ..) will do the right thing.

NLA_BE64 can be added later.

Fixes: 08724ef69907 ("netlink: introduce NLA_POLICY_MAX_BE")
Reported-by: Jakub Kicinski <[e-mail]>
Suggested-by: Johannes Berg <[e-mail]>
Signed-off-by: Florian Westphal <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

include/net/netlink.h

···
 	NLA_S64,
 	NLA_BITFIELD32,
 	NLA_REJECT,
+	NLA_BE16,
+	NLA_BE32,
 	__NLA_TYPE_MAX,
 };
 
···
  *    NLA_U32, NLA_U64,
  *    NLA_S8, NLA_S16,
  *    NLA_S32, NLA_S64,
+ *    NLA_BE16, NLA_BE32,
  *    NLA_MSECS            Leaving the length field zero will verify the
  *                         given type fits, using it verifies minimum length
  *                         just like "All other"
···
  *    NLA_U16,
  *    NLA_U32,
  *    NLA_U64,
+ *    NLA_BE16,
+ *    NLA_BE32,
  *    NLA_S8,
  *    NLA_S16,
  *    NLA_S32,
···
 		struct netlink_range_validation_signed *range_signed;
 		struct {
 			s16 min, max;
-			u8 network_byte_order:1;
 		};
 		int (*validate)(const struct nlattr *attr,
 				struct netlink_ext_ack *extack);
···
 	(tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || tp == NLA_U64)
 #define __NLA_IS_SINT_TYPE(tp)						\
 	(tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64)
+#define __NLA_IS_BEINT_TYPE(tp)						\
+	(tp == NLA_BE16 || tp == NLA_BE32)
 
 #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition))
 #define NLA_ENSURE_UINT_TYPE(tp)			\
···
 #define NLA_ENSURE_INT_OR_BINARY_TYPE(tp)		\
 	(__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) ||		\
 		      __NLA_IS_SINT_TYPE(tp) ||		\
+		      __NLA_IS_BEINT_TYPE(tp) ||	\
 		      tp == NLA_MSECS ||		\
 		      tp == NLA_BINARY) + tp)
 #define NLA_ENSURE_NO_VALIDATION_PTR(tp)		\
···
 		      tp != NLA_REJECT &&		\
 		      tp != NLA_NESTED &&		\
 		      tp != NLA_NESTED_ARRAY) + tp)
+#define NLA_ENSURE_BEINT_TYPE(tp)			\
+	(__NLA_ENSURE(__NLA_IS_BEINT_TYPE(tp)) + tp)
 
 #define NLA_POLICY_RANGE(tp, _min, _max) {		\
 	.type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp),	\
···
 	.type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp),	\
 	.validation_type = NLA_VALIDATE_MAX,		\
 	.max = _max,					\
-	.network_byte_order = 0,			\
-}
-
-#define NLA_POLICY_MAX_BE(tp, _max) {			\
-	.type = NLA_ENSURE_UINT_TYPE(tp),		\
-	.validation_type = NLA_VALIDATE_MAX,		\
-	.max = _max,					\
-	.network_byte_order = 1,			\
 }
 
 #define NLA_POLICY_MASK(tp, _mask) {			\

lib/nlattr.c

···
 		range->max = U8_MAX;
 		break;
 	case NLA_U16:
+	case NLA_BE16:
 	case NLA_BINARY:
 		range->max = U16_MAX;
 		break;
 	case NLA_U32:
+	case NLA_BE32:
 		range->max = U32_MAX;
 		break;
 	case NLA_U64:
···
 	}
 }
 
-static u64 nla_get_attr_bo(const struct nla_policy *pt,
-			   const struct nlattr *nla)
-{
-	switch (pt->type) {
-	case NLA_U16:
-		if (pt->network_byte_order)
-			return ntohs(nla_get_be16(nla));
-
-		return nla_get_u16(nla);
-	case NLA_U32:
-		if (pt->network_byte_order)
-			return ntohl(nla_get_be32(nla));
-
-		return nla_get_u32(nla);
-	case NLA_U64:
-		if (pt->network_byte_order)
-			return be64_to_cpu(nla_get_be64(nla));
-
-		return nla_get_u64(nla);
-	}
-
-	WARN_ON_ONCE(1);
-	return 0;
-}
-
 static int nla_validate_range_unsigned(const struct nla_policy *pt,
 				       const struct nlattr *nla,
 				       struct netlink_ext_ack *extack,
···
 		value = nla_get_u8(nla);
 		break;
 	case NLA_U16:
+		value = nla_get_u16(nla);
+		break;
 	case NLA_U32:
+		value = nla_get_u32(nla);
+		break;
 	case NLA_U64:
-		value = nla_get_attr_bo(pt, nla);
+		value = nla_get_u64(nla);
 		break;
 	case NLA_MSECS:
 		value = nla_get_u64(nla);
 		break;
 	case NLA_BINARY:
 		value = nla_len(nla);
+		break;
+	case NLA_BE16:
+		value = ntohs(nla_get_be16(nla));
+		break;
+	case NLA_BE32:
+		value = ntohl(nla_get_be32(nla));
 		break;
 	default:
 		return -EINVAL;
···
 	case NLA_U64:
 	case NLA_MSECS:
 	case NLA_BINARY:
+	case NLA_BE16:
+	case NLA_BE32:
 		return nla_validate_range_unsigned(pt, nla, extack, validate);
 	case NLA_S8:
 	case NLA_S16:

net/netfilter/nft_payload.c

···
 	[NFTA_PAYLOAD_SREG]		= { .type = NLA_U32 },
 	[NFTA_PAYLOAD_DREG]		= { .type = NLA_U32 },
 	[NFTA_PAYLOAD_BASE]		= { .type = NLA_U32 },
-	[NFTA_PAYLOAD_OFFSET]		= NLA_POLICY_MAX_BE(NLA_U32, 255),
-	[NFTA_PAYLOAD_LEN]		= NLA_POLICY_MAX_BE(NLA_U32, 255),
+	[NFTA_PAYLOAD_OFFSET]		= NLA_POLICY_MAX(NLA_BE32, 255),
+	[NFTA_PAYLOAD_LEN]		= NLA_POLICY_MAX(NLA_BE32, 255),
 	[NFTA_PAYLOAD_CSUM_TYPE]	= { .type = NLA_U32 },
-	[NFTA_PAYLOAD_CSUM_OFFSET]	= NLA_POLICY_MAX_BE(NLA_U32, 255),
+	[NFTA_PAYLOAD_CSUM_OFFSET]	= NLA_POLICY_MAX(NLA_BE32, 255),
 	[NFTA_PAYLOAD_CSUM_FLAGS]	= { .type = NLA_U32 },
 };