From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-178.mta1.migadu.com (out-178.mta1.migadu.com [95.215.58.178]) (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 93EF03CA48E for ; Thu, 9 Apr 2026 12:41:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.178 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775738517; cv=none; b=EE7VVspHyN5Z811CVJMuEy/twkH+fSzOlSRgOW+fzmHpeI8p7LwvGK3NaQ94XsAN0LjEtZ28QGoZi2L6lueNXb3eJFyAfboVco3T4SaqUj9OXyLmIL4Nw29n9gn5llXRBzCnKFXed7AlVwgfaNegg+WoOSN+pVM5Yf5scZKW4e0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775738517; c=relaxed/simple; bh=1h2eE+ZXSVBi99s1ooRWuTXnyVDsueCr8U32HZ7pirs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=NkiQCyLUksYS4cf9U95msr554gL5uUGWpZR0NSfp5j0837etKcCUh0sZXdcM4a2oMFRRVXHjlIocnm2NJ3P8F5+mi5vfDOQYT/TdCdGsQMedgpesCcFw8qItpOn3lev1sLThLegcgv92ly0ZWjCdxUTCfzLSDCMHde78uvvsMZQ= 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=eg5uQhYg; arc=none smtp.client-ip=95.215.58.178 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="eg5uQhYg" 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=1775738503; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Z5NTXRA3IgJaqDeXGrXT2GIDlsVP616rrMljWaw2KCk=; b=eg5uQhYglWeSQXx5j09bpFCOIN8e6DCQbQI+88JHo1n7OQCbBwSqDfP8MFkGC0Sl2V526T nEgh88dgPXu++T7+JEwZ2jB2sRcAD42MPPolAP6UfTyMTHGyXkENiYuZEAXsvOu359xKKn pyIbw/ZdbPu0vSJcjRV2D12lpGvQ8Yk= From: Jiayuan Chen To: netdev@vger.kernel.org Cc: Jiayuan Chen , Eric Dumazet , Neal Cardwell , Kuniyuki Iwashima , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , David Ahern , linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH net-next v1] net: add missing syncookie statistics for BPF custom syncookies Date: Thu, 9 Apr 2026 20:41:28 +0800 Message-ID: <20260409124129.361777-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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_SYSCALL guard around struct bpf_tcp_req_attrs. This struct is referenced by bpf_sk_assign_tcp_reqsk() in net/core/filter.c which is compiled unconditionally, so wrapping the definition in a config guard could cause build failures when CONFIG_BPF_SYSCALL=n. 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 --- No functional bug here — CONFIG_BPF is always enabled under CONFIG_NET, so the existing code compiles and works correctly. This is a cleanup and improvement, no backport needed. --- 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 6156d1d068e1..570a8836c2ba 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -598,7 +598,6 @@ 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; @@ -612,7 +611,6 @@ struct bpf_tcp_req_attrs { u8 usec_ts_ok; u8 reserved[3]; }; -#endif #ifdef CONFIG_SYN_COOKIES @@ -715,13 +713,14 @@ 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 f1474598d2c8..d685631438cb 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -295,8 +295,9 @@ 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); @@ -306,6 +307,9 @@ 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 4f6f0d751d6c..111d7a41d957 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