From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) (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 F0F2A3B9D94 for ; Thu, 14 May 2026 05:10:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735441; cv=none; b=nsi+H3R76RrB0FMWi11j+J1r6vw8HSSONLIXusmX6QHsPX5dtMVzkccHp3tFc1+SHR5gSCUmdGMpiYN8lgtyVR73M88lP1cO7nlCYWmEJug51QQ8t8+GaoILz3Rtrst4RhwHGjeB+5k8YW03Y39sWltnAbj1o7iDWRKO0BeJyZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735441; c=relaxed/simple; bh=HscCd40h4IXjgl6QvhloOnaj1tz+SpMNc1axYSXQjjk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UZUa718V3AG/zkxiytYWSluV0jE/Oxra7i3n33TrWbWCBNP4KOpLb847UEs8hrgTJfsOkjgYflf/zFF4kLGYvUdQ0/qv9aVRgtNQqJh7RJiNiX1SIjldKS5V/IVCt+1RR2hBGNtUll1XXdsGKBuFgf/7ouJwACIlbBgQtwK9Q2E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=MrEbvadi; arc=none smtp.client-ip=91.218.175.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="MrEbvadi" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778735436; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=U0DhVK8ibYLXXtHt744ue2KCHhBHIPe4oMwlveBBIeI=; b=MrEbvadiWOwbxhclbAmgsiNemFCOrHDnxWFpAXYo1pKsuJL0M+8BvOJqnUr/1X7EXXd4rU RAelj39/DLE9e8p9lcQcnf8QhB1N83qGq0B0uzI2DK6EsIFqOavv6pGBTBExABlhjXmPD7 2GZJaY7FkgNfItbt7JVNHSy//2T4Ahw= From: Jiayuan Chen To: bpf@vger.kernel.org Cc: Jiayuan Chen , Kuniyuki Iwashima , Eric Dumazet , Neal Cardwell , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Andrii Nakryiko , Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Shuah Khan , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v4 1/2] net: add missing syncookie statistics for BPF custom syncookies Date: Thu, 14 May 2026 13:09:57 +0800 Message-ID: <20260514051015.177926-2-jiayuan.chen@linux.dev> In-Reply-To: <20260514051015.177926-1-jiayuan.chen@linux.dev> References: <20260514051015.177926-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 1. Replace IS_ENABLED(CONFIG_BPF) with CONFIG_BPF_SYSCALL for cookie_bpf_ok() and cookie_bpf_check(). CONFIG_BPF is selected by CONFIG_NET unconditionally, so IS_ENABLED(CONFIG_BPF) is always true and provides no real guard. CONFIG_BPF_SYSCALL is the correct config for BPF program functionality. 2. Remove the CONFIG_BPF guard around struct bpf_tcp_req_attrs. Since CONFIG_BPF is always selected by CONFIG_NET the guard is a no-op, and the struct is referenced by bpf_sk_assign_tcp_reqsk() in net/core/filter.c which is compiled unconditionally, so its visibility is not actually conditional on BPF being enabled. 3. Fix mismatched declaration of cookie_bpf_check() between the CONFIG_BPF_SYSCALL and stub paths: the real definition takes 'struct net *net' but the declaration in the header did not. Add the net parameter to the declaration and all call sites. 4. Add missing LINUX_MIB_SYNCOOKIESRECV and LINUX_MIB_SYNCOOKIESFAILED statistics in cookie_bpf_check(), so that BPF custom syncookie validation is accounted for in SNMP counters just like the non-BPF path. Compile-tested with CONFIG_BPF_SYSCALL=y and CONFIG_BPF_SYSCALL not set. Signed-off-by: Jiayuan Chen Reviewed-by: Kuniyuki Iwashima --- To sashiko: We already called skb->sk = NULL before calling reqsk_free(req). So there is no worry about skb->sk becoming dangling pointer after cookie_tcp_reqsk_init() fails. --- include/net/tcp.h | 7 +++---- net/ipv4/syncookies.c | 10 +++++++--- net/ipv6/syncookies.c | 2 +- 3 files changed, 11 insertions(+), 8 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index ecbadcb3a7446..7d87bc2d21d17 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -599,7 +599,6 @@ struct request_sock *cookie_tcp_reqsk_alloc(const struct request_sock_ops *ops, struct tcp_options_received *tcp_opt, int mss, u32 tsoff); -#if IS_ENABLED(CONFIG_BPF) struct bpf_tcp_req_attrs { u32 rcv_tsval; u32 rcv_tsecr; @@ -613,7 +612,6 @@ struct bpf_tcp_req_attrs { u8 usec_ts_ok; u8 reserved[3]; }; -#endif #ifdef CONFIG_SYN_COOKIES @@ -716,13 +714,14 @@ static inline bool cookie_ecn_ok(const struct net *net, const struct dst_entry * dst_feature(dst, RTAX_FEATURE_ECN); } -#if IS_ENABLED(CONFIG_BPF) +#ifdef CONFIG_BPF_SYSCALL static inline bool cookie_bpf_ok(struct sk_buff *skb) { return skb->sk; } -struct request_sock *cookie_bpf_check(struct sock *sk, struct sk_buff *skb); +struct request_sock *cookie_bpf_check(struct net *net, struct sock *sk, + struct sk_buff *skb); #else static inline bool cookie_bpf_ok(struct sk_buff *skb) { diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index df479277fb801..9251d4a15c888 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -294,8 +294,9 @@ static int cookie_tcp_reqsk_init(struct sock *sk, struct sk_buff *skb, return 0; } -#if IS_ENABLED(CONFIG_BPF) -struct request_sock *cookie_bpf_check(struct sock *sk, struct sk_buff *skb) +#ifdef CONFIG_BPF_SYSCALL +struct request_sock *cookie_bpf_check(struct net *net, struct sock *sk, + struct sk_buff *skb) { struct request_sock *req = inet_reqsk(skb->sk); @@ -305,6 +306,9 @@ struct request_sock *cookie_bpf_check(struct sock *sk, struct sk_buff *skb) if (cookie_tcp_reqsk_init(sk, skb, req)) { reqsk_free(req); req = NULL; + __NET_INC_STATS(net, LINUX_MIB_SYNCOOKIESFAILED); + } else { + __NET_INC_STATS(net, LINUX_MIB_SYNCOOKIESRECV); } return req; @@ -419,7 +423,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb) goto out; if (cookie_bpf_ok(skb)) { - req = cookie_bpf_check(sk, skb); + req = cookie_bpf_check(net, sk, skb); } else { req = cookie_tcp_check(net, sk, skb); if (IS_ERR(req)) diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 4f6f0d751d6c5..111d7a41d9573 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -190,7 +190,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) goto out; if (cookie_bpf_ok(skb)) { - req = cookie_bpf_check(sk, skb); + req = cookie_bpf_check(net, sk, skb); } else { req = cookie_tcp_check(net, sk, skb); if (IS_ERR(req)) -- 2.43.0