From nobody Mon Feb 9 10:42:33 2026 Received: from mail-wm1-f50.google.com (mail-wm1-f50.google.com [209.85.128.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F1753D7D78 for ; Wed, 4 Feb 2026 12:25:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770207935; cv=none; b=BVJzZTZHkZuibKdMqiKi4gAaRG8eSolI9uKizkw2GB/094JYggMu9RUPrezRK+EN77XuEXsEZO3DeuSzaxhTPWeqgbL7gciB1oiisSOdCUU57/D/xJuWPRWiMEQJH1UTcdv2QdkOCouGIL1yzebxcFEnbhx3qe0ATjKSnj3G1Nc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770207935; c=relaxed/simple; bh=442GijrACNIyhOO1PCXlk5yOxBA5l2sO0BEtkSrO/ac=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=qOQt9ysfLUWPcGvuE3pa3hFUTvSfzmXUoQZNs1Wkyw3u9xjldZibFtMSzN5kIh5WIfiNqvoxYEkMU1E4Q5sKd60FqX7V6NqCrVu6MO7UjJp+cSPVn21EWh4GXR98iDrwrlIE9DxXqjtnnDtV6qTG1/RK/RAKHbxDlU48u+uD5zw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=cloudflare.com; spf=pass smtp.mailfrom=cloudflare.com; dkim=pass (2048-bit key) header.d=cloudflare.com header.i=@cloudflare.com header.b=PW9jpWSq; arc=none smtp.client-ip=209.85.128.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=cloudflare.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cloudflare.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cloudflare.com header.i=@cloudflare.com header.b="PW9jpWSq" Received: by mail-wm1-f50.google.com with SMTP id 5b1f17b1804b1-480142406b3so50813975e9.1 for ; Wed, 04 Feb 2026 04:25:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google09082023; t=1770207934; x=1770812734; darn=vger.kernel.org; h=cc:to:message-id:content-transfer-encoding:mime-version:subject :date:from:from:to:cc:subject:date:message-id:reply-to; bh=yH8MXVCKtWqJdP7mij43Xe3QvXlt93YlWk5c/5DsI+Y=; b=PW9jpWSqEFr9vYeuiN1hEZNBDMAP07jDPrQVot+jcRcfJegIBAUAvqPFVp7nBjrQQI RcRvvRS1Y+fiGd7s69W7A0f0LWwQPy77iG6HMiUJ0gwA789dYIpkIEjTWNiuhG6ujT0b EwJvgAqMJpLi4o7lUxJAlAgjgNGjyWTAs0X+IiYYkrdyf4YmiYceQGpaVZGthYxXKxTZ BhB47D8lOh+ef4Yr5tVL4P26LAqdtzFj0X1KjVj6DBTAUD6yhQ60gjCgyRU3BihFfo/7 jkeVDJzkiV84q6ClqArOmpmeMyawUu3Ti2iTIA7eebIk1fADUJFFRbKSMe+00e41LzD7 C9eg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770207934; x=1770812734; h=cc:to:message-id:content-transfer-encoding:mime-version:subject :date:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=yH8MXVCKtWqJdP7mij43Xe3QvXlt93YlWk5c/5DsI+Y=; b=cBKX5R8m0w082+GFV7cmc+4ddgmlNvpyoRMW42PAC1ad79zH4Io3L9CJT97DkCn8tz tsZ5U9amBH+6P4S61QVXi5qDMml423yBmFd4hf4FLzObN5FbVRVA9oARsVDFAxKALkP6 CH4bQYyRQAJgrwoM+4/g8BfT1V7oN2rs8l+fSIh1hTadzl9IY1ceSYbpgxwTXMCT1/mS QU8iwOv2b4E7EW9ZyIua2WZJP9MfejU2vyVrG4ZpBNYI6bsPapqWO4gHZ1acl68XpkUh U5suTUBl+N4CtcUhxO0fghhsAm4PUQm/nCR3S1/AYKT/bdGynUlYTmOCPITJk3fNDMAU 0/0A== X-Forwarded-Encrypted: i=1; AJvYcCVJFS2vJMugfxKKpra0m2xO76TtGzYaKudUGopdH2UM5BddzD3yXvjxUrg5CqWUax9MbHv9yDu+R8ra3i0=@vger.kernel.org X-Gm-Message-State: AOJu0Yzkvh4rwWx0zE98R3/yjKMs4sKmvdp8aoTjHQaD2M03NoXUrd1S cCDJPOA2058DbZ8oTaa+6Wq7+rUlzuavYG4Io8RNLWHzzTWVtuxNA8kYct6KxYn7CxU= X-Gm-Gg: AZuq6aL3UAyrZGgRUE8sNDEloS0uqIm2HOJmfz7OH98HPJ3OjcvPGFZRwwB18KE5d8c a0MnLi7PFnihRFQKTRguIaDRuU45sXCcSrqExOyM58ax6/I4sEtEcUrJgiubPyUE8rS76C6kXzv HOwChyR1Dq8M98U71eqLQUFTwgceG+M8BrduCmguKnFN2WZVy1dcEKYXbGfNJb77Yb3TOlEXrii q2EM8TsU+miPbCEJfigTY6sOnNQdmn2fURpG/ac3RsbuCmEBvDjdxsdtvCzC1aZSNL23V90ytet I5h8KrLNpUygRk886Mef2J/N6TxEXRs9Dd3bEZYGyQS/iRM6b1PhwB1jj2gl1+9qu/hx2Bi9nzM HFed813CjG7LRqYYLhmm4tJorWDhWpp752rhlHFXBRBwRHCp/PwnXgmca40cjAWEYy3IGZ5G4Su RpTcxfkHQVQir7Vr4Tnf/5A4e/5JsuC4tL7bhNic79zssj X-Received: by 2002:a05:6000:240b:b0:435:9a4a:9b79 with SMTP id ffacd0b85a97d-43618052a8bmr3855745f8f.31.1770207933548; Wed, 04 Feb 2026 04:25:33 -0800 (PST) Received: from [127.0.1.1] (24.162.85.79.rev.sfr.net. [79.85.162.24]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4361805f25dsm6377318f8f.29.2026.02.04.04.25.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Feb 2026 04:25:33 -0800 (PST) From: Arthur Fabre Date: Wed, 04 Feb 2026 13:24:56 +0100 Subject: [PATCH bpf-next] bpf: Allow bpf_tcp_sock() helper in XDP Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260204-afabre-bpf_tcp_sock-v1-1-a22b40c630c0@cloudflare.com> X-B4-Tracking: v=1; b=H4sIAJc6g2kC/x2MQQqAIBAAvxJ7bmHVKOgrEWG21hKYaEQQ/T3pO DAzD2ROwhn66oHEl2Q5QgFVV+A2G1ZGWQqDJt2Spgatt3NinKOfThenfLgdleoWMq71xAZKGRN 7uf/rAMXEwPcJ4/t+BgR9928AAAA= X-Change-ID: 20260204-afabre-bpf_tcp_sock-117d03c6f0e3 To: Martin KaFai Lau , Daniel Borkmann , John Fastabend , Stanislav Fomichev , Alexei Starovoitov , Andrii Nakryiko , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Hao Luo , Jiri Olsa , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@cloudflare.com, wferguson@cloudflare.com, Arthur Fabre X-Mailer: b4 0.14.2 We can already lookup sockets in XDP via the bpf_sk(c)_lookup_(udp|tcp) helpers. This can be used to determine if a received packet is for an established socket or not, for example in a load balancer. But the TCP TIME-WAIT state needs special handling for this: packets received for a TIME-WAIT socket can either belong to the current incarnation of the connection, or a new incarnation. The only way to determine this is to compare the sequence numbers. Add the bpf_tcp_sock() helper in XDP to allow the socket sequence numbers to be read. --- Signed-off-by: Arthur Fabre --- net/core/filter.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/core/filter.c b/net/core/filter.c index f04982d79d72e92f1b46ccd87633391e38c3da81..5e3a1951130369f070c3a373ea6= 49bd10db412b6 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8506,6 +8506,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct= bpf_prog *prog) return &bpf_sk_release_proto; case BPF_FUNC_skc_lookup_tcp: return &bpf_xdp_skc_lookup_tcp_proto; + case BPF_FUNC_tcp_sock: + return &bpf_tcp_sock_proto; case BPF_FUNC_tcp_check_syncookie: return &bpf_tcp_check_syncookie_proto; case BPF_FUNC_tcp_gen_syncookie: --- base-commit: d95d76aa772bf94df353b015b1cb38303d4a415d change-id: 20260204-afabre-bpf_tcp_sock-117d03c6f0e3 Best regards, --=20 Arthur Fabre