[PATCH 6.1 061/312] netlink: allow be16 and be32 types in all uint policy checks

Greg Kroah-Hartman
2026-04-08T18:09:28Z

From: Florian Westphal <fw@strlen.de>

[ Upstream commit 5fac9b7c16c50c6c7699517f582b56e3743f453a ]

__NLA_IS_BEINT_TYPE(tp) isn't useful. NLA_BE16/32 are identical to
NLA_U16/32, the only difference is that it tells the netlink validation
functions that byteorder conversion might be needed before comparing
the value to the policy min/max ones.

After this change all policy macros that can be used with UINT types,
such as NLA_POLICY_MASK() can also be used with NLA_BE16/32.

This will be used to validate nf_tables flag attributes which
are in bigendian byte order.

Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 8f15b5071b45 ("netfilter: ctnetlink: use netlink policy range checks")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/netlink.h | 10 +++-------
lib/nlattr.c | 6 ++++++
2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 6e1e670e06bc4..df8012ef85f1d 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -374,12 +374,11 @@ struct nla_policy {
#define NLA_POLICY_BITFIELD32(valid) \
{ .type = NLA_BITFIELD32, .bitfield32_valid = valid }

-#define __NLA_IS_UINT_TYPE(tp) \
- (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || tp == NLA_U64)
+#define __NLA_IS_UINT_TYPE(tp) \
+ (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || \
+ tp == NLA_U64 || tp == NLA_BE16 || tp == NLA_BE32)
#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) \
@@ -393,7 +392,6 @@ struct nla_policy {
#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) \
@@ -401,8 +399,6 @@ struct nla_policy {
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), \
diff --git a/lib/nlattr.c b/lib/nlattr.c
index 86344df0ccf7b..cf5f0dc3e47d6 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -359,6 +359,12 @@ static int nla_validate_mask(const struct nla_policy *pt,
case NLA_U64:
value = nla_get_u64(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;
}
--
2.51.0