From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.netfilter.org (mail.netfilter.org [217.70.190.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1223223D2AB; Thu, 26 Mar 2026 12:52:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.190.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774529537; cv=none; b=cEFS7oKr1BdxXhCRfTMTeNyrZWClmBsfvKmzPriq1EUZP0pdOCsI6IJMTRBILhx/7+7Z44twp+NztDkeQT1AT7IE/C3QI6lZ8rtnxKHiGEdskCKDAKyW36EUhrUazwUTpNVQxsh8S4fB4qPoP9bIIaQVcnx5EI0H1i+QpwBDww8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774529537; c=relaxed/simple; bh=p3BC6hh9fW+7jRDjxwF/oC2PzTjoSAf5VECZcqHqTJc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ekctovfvduBrwqXsrT4S/kn9kiKxJKMM50qxEb7fRPosvH4lEpTl4cmottYQWSAoLQ7McG0PfnFRxVLuphqBcF+SuuyzWDmNl/i8x80KGtbYVDWAVCu3oOCstrt8uVbKnkEFqVtEs+7RZ00FgnTsR5JBwu323Y9KqGF6u2lMIxM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b=pb0HrXW+; arc=none smtp.client-ip=217.70.190.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b="pb0HrXW+" Received: from localhost.localdomain (mail-agni [217.70.190.124]) by mail.netfilter.org (Postfix) with ESMTPSA id DA1096026D; Thu, 26 Mar 2026 13:52:11 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netfilter.org; s=2025; t=1774529532; bh=lm1MgmEPExXmZ/44UAb/bzWwRl79gcVYhzAAvZyGJmk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pb0HrXW+mnB15IPW0LGaJMA5UlV2XuUnD8i/1+tcLbY2BrGuwzFRYF2JUJdRxi4oC Be3lMhLbhMKTbyO5tQnjtaXJwc0TEU95/zr577HM/sL0fLswYvb1IKzbNe/XtWrJvg uPbs/HZ6FKMgeVghEYcjmDUmZ8c4Ow1Au8qjWTlD1kRKH1W60JIVesfku+w7gJ4VI6 nlbR2o+5hHl94uWI2g8XXu/xxSiI7DEhfTUTogIaZT/Q8NjYEkbjYnyGqmnSj8E7LI Paxaw90QDGc9lK3E8uhsUPbpLJUUo09QJnufkrSTjT2oBaXxypN84+CsR8HJYHmEB9 3H6FD52MRFFbw== From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, fw@strlen.de, horms@kernel.org Subject: [PATCH net 12/12] netfilter: ctnetlink: use netlink policy range checks Date: Thu, 26 Mar 2026 13:51:53 +0100 Message-ID: <20260326125153.685915-13-pablo@netfilter.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260326125153.685915-1-pablo@netfilter.org> References: <20260326125153.685915-1-pablo@netfilter.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: David Carlier Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects invalid values early and can generate extack errors. - CTA_PROTOINFO_TCP_STATE: reject values > TCP_CONNTRACK_SYN_SENT2 at policy level, removing the manual >= TCP_CONNTRACK_MAX check. - CTA_PROTOINFO_TCP_WSCALE_ORIGINAL/REPLY: reject values > TCP_MAX_WSCALE (14). The normal TCP option parsing path already clamps to this value, but the ctnetlink path accepted 0-255, causing undefined behavior when used as a u32 shift count. - CTA_FILTER_ORIG_FLAGS/REPLY_FLAGS: use NLA_POLICY_MASK with CTA_FILTER_F_ALL, removing the manual mask checks. - CTA_EXPECT_FLAGS: use NLA_POLICY_MASK with NF_CT_EXPECT_MASK, adding a new mask define grouping all valid expect flags. Extracted from a broader nf-next patch by Florian Westphal, scoped to ctnetlink for the fixes tree. Fixes: c8e2078cfe41 ("[NETFILTER]: ctnetlink: add support for internal tcp connection tracking flags handling") Signed-off-by: David Carlier Co-developed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- .../uapi/linux/netfilter/nf_conntrack_common.h | 4 ++++ net/netfilter/nf_conntrack_netlink.c | 16 +++++----------- net/netfilter/nf_conntrack_proto_tcp.c | 10 +++------- 3 files changed, 12 insertions(+), 18 deletions(-) diff --git a/include/uapi/linux/netfilter/nf_conntrack_common.h b/include/uapi/linux/netfilter/nf_conntrack_common.h index 26071021e986..56b6b60a814f 100644 --- a/include/uapi/linux/netfilter/nf_conntrack_common.h +++ b/include/uapi/linux/netfilter/nf_conntrack_common.h @@ -159,5 +159,9 @@ enum ip_conntrack_expect_events { #define NF_CT_EXPECT_INACTIVE 0x2 #define NF_CT_EXPECT_USERSPACE 0x4 +#ifdef __KERNEL__ +#define NF_CT_EXPECT_MASK (NF_CT_EXPECT_PERMANENT | NF_CT_EXPECT_INACTIVE | \ + NF_CT_EXPECT_USERSPACE) +#endif #endif /* _UAPI_NF_CONNTRACK_COMMON_H */ diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 6e6aeb0ab0a1..3f408f3713bb 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -910,8 +910,8 @@ struct ctnetlink_filter { }; static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = { - [CTA_FILTER_ORIG_FLAGS] = { .type = NLA_U32 }, - [CTA_FILTER_REPLY_FLAGS] = { .type = NLA_U32 }, + [CTA_FILTER_ORIG_FLAGS] = NLA_POLICY_MASK(NLA_U32, CTA_FILTER_F_ALL), + [CTA_FILTER_REPLY_FLAGS] = NLA_POLICY_MASK(NLA_U32, CTA_FILTER_F_ALL), }; static int ctnetlink_parse_filter(const struct nlattr *attr, @@ -925,17 +925,11 @@ static int ctnetlink_parse_filter(const struct nlattr *attr, if (ret) return ret; - if (tb[CTA_FILTER_ORIG_FLAGS]) { + if (tb[CTA_FILTER_ORIG_FLAGS]) filter->orig_flags = nla_get_u32(tb[CTA_FILTER_ORIG_FLAGS]); - if (filter->orig_flags & ~CTA_FILTER_F_ALL) - return -EOPNOTSUPP; - } - if (tb[CTA_FILTER_REPLY_FLAGS]) { + if (tb[CTA_FILTER_REPLY_FLAGS]) filter->reply_flags = nla_get_u32(tb[CTA_FILTER_REPLY_FLAGS]); - if (filter->reply_flags & ~CTA_FILTER_F_ALL) - return -EOPNOTSUPP; - } return 0; } @@ -2634,7 +2628,7 @@ static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = { [CTA_EXPECT_HELP_NAME] = { .type = NLA_NUL_STRING, .len = NF_CT_HELPER_NAME_LEN - 1 }, [CTA_EXPECT_ZONE] = { .type = NLA_U16 }, - [CTA_EXPECT_FLAGS] = { .type = NLA_U32 }, + [CTA_EXPECT_FLAGS] = NLA_POLICY_MASK(NLA_BE32, NF_CT_EXPECT_MASK), [CTA_EXPECT_CLASS] = { .type = NLA_U32 }, [CTA_EXPECT_NAT] = { .type = NLA_NESTED }, [CTA_EXPECT_FN] = { .type = NLA_NUL_STRING }, diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index 0c1d086e96cb..b67426c2189b 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -1385,9 +1385,9 @@ static int tcp_to_nlattr(struct sk_buff *skb, struct nlattr *nla, } static const struct nla_policy tcp_nla_policy[CTA_PROTOINFO_TCP_MAX+1] = { - [CTA_PROTOINFO_TCP_STATE] = { .type = NLA_U8 }, - [CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] = { .type = NLA_U8 }, - [CTA_PROTOINFO_TCP_WSCALE_REPLY] = { .type = NLA_U8 }, + [CTA_PROTOINFO_TCP_STATE] = NLA_POLICY_MAX(NLA_U8, TCP_CONNTRACK_SYN_SENT2), + [CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] = NLA_POLICY_MAX(NLA_U8, TCP_MAX_WSCALE), + [CTA_PROTOINFO_TCP_WSCALE_REPLY] = NLA_POLICY_MAX(NLA_U8, TCP_MAX_WSCALE), [CTA_PROTOINFO_TCP_FLAGS_ORIGINAL] = { .len = sizeof(struct nf_ct_tcp_flags) }, [CTA_PROTOINFO_TCP_FLAGS_REPLY] = { .len = sizeof(struct nf_ct_tcp_flags) }, }; @@ -1414,10 +1414,6 @@ static int nlattr_to_tcp(struct nlattr *cda[], struct nf_conn *ct) if (err < 0) return err; - if (tb[CTA_PROTOINFO_TCP_STATE] && - nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]) >= TCP_CONNTRACK_MAX) - return -EINVAL; - spin_lock_bh(&ct->lock); if (tb[CTA_PROTOINFO_TCP_STATE]) ct->proto.tcp.state = nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]); -- 2.47.3