From nobody Thu Apr 9 09:01:53 2026 Received: from mail-ot1-f41.google.com (mail-ot1-f41.google.com [209.85.210.41]) (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 A150A1FC0EF for ; Tue, 10 Mar 2026 01:26:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.41 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773106010; cv=none; b=Jg0nk2V3rft9p5LMDauNKg/WO/Lz98hZHhqXY+Wq6wApewTuZbLtPT3kDHYQjR9Z+01a8V35JC/9VAxZvteSVLFNLc8Zrx8bjTdtf/r9oMWsQWhkOdmlyBPkvjDWvOc385GrI7yoAuCmK3JBW5YWGn/zoz5PF/J+k+gx2sBrMJo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773106010; c=relaxed/simple; bh=i/CfK21xcP2Dl86/EdnOmx6/a4l8tDz5u5jRT4QD5gg=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=lhmG9ATG5QjYm60tl3XqUf2JqfsUbd67JIn3w5w/CHU0H4b1IJUnZ4+ZDrYK2if+Rws1WgbEAHxMRL9GttdLSDNZYqgpYVtfEZzT1OfuyBZyuFxwd8ShGT5n7hddHpKo0TCb4hKiAEjmv+LFkGoYQCULmQzeqmixRcBgee2lESU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=AQBZk145; arc=none smtp.client-ip=209.85.210.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="AQBZk145" Received: by mail-ot1-f41.google.com with SMTP id 46e09a7af769-7d7447778b9so945166a34.2 for ; Mon, 09 Mar 2026 18:26:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1773106008; x=1773710808; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=kIoAs5tKx7jwvMk/e5P+rCsogpkNXx41D3oZZZC2J4s=; b=AQBZk1458nLi8cp5pK4FuRKMUZBPNd8dHXstUVQV55BSHiaQsfmoTtkWNxM0osAASx f4AvFLNte7fGZb5oO8Lgs1SGAA+7fvGyabOEVm//0xWKPw1rMVAcjh5kzkfY9GdDYfYb SKymcZpyKPhLIo30HKEuvkgMkGgj3IylgkdWebWo7WHgmJm+iy3YxVc8LfO5z1B/zoxq Q2OiK6efG9rKXe8JdYd/NEdm/6UouU4ONl+tWI/PyqVUDdI/ka95rfBUfDvVl7IVkYkB CeAS//6O8ObAzu0GFQGe8Dx6zYOWZt8JmnB1wYUUrdKlwr2sft/4whFOOhsUBLj2NPXU CLaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1773106008; x=1773710808; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=kIoAs5tKx7jwvMk/e5P+rCsogpkNXx41D3oZZZC2J4s=; b=t3xlmgM2ytjm/hslzwIkDcHY+MwiTziLYzgA/Sg/Zyee3+f8Tv54dDpkc6KDRF4jdC Qy4YkTSdYEvETT/7iWB1LDwhSQpUqlwgxdcEsVsYE71JPf7XrnbVhthdvkxBqJ1rTOd9 NO3zc7yz7bLTgXBxgZtv9vzBsKuIKMztXVwngQGx8i+jW9d9HZOhdbGfyyiSPx/hxZL8 RSkChq22OPvbBooS1nAzfmmIMYS/lvZVzp+9qGHRrpiZJDQTix2zqPc35ei0UsJK/JwA MgZvBW9yEimAHTPjxfIcVm/yltEaYFF+eT4pVPilOtn50lwuF1i9g0aL8GMGguNKKKVW t+gQ== X-Forwarded-Encrypted: i=1; AJvYcCU5kgHCYDnUAmYJQmBozJRYNAV6k+vwgP558plxc+i0JKIx8Vk85FIDyl5+hKVUSNuxDniwGNCUiTvqDX0=@vger.kernel.org X-Gm-Message-State: AOJu0YyzWk28tK34jLFcFp7cVscbS9blM0QN4x9saMhPK8oYDR2qFTWf b88F8cK5la++Ckf4cl6oeM1ffxocGI4lJkQIgC3WrM44tITRvl//t0+Q X-Gm-Gg: ATEYQzxl0gVQa6Aq8tWw9uFFUUloFdv0Pb6BD3Hx55kpsL4TftrXDIcOatCXaeWsvWF VDWdSYgGNz+KcTbMDeiYcM/qw0sJPlHUm8cadIXy7DKnduyHVNvCIc5IFTpLqkvsmB2E5Yvj9st Tkla6L8a9BpXZAKzrnL1C+x9Nq4P6p1cuTuYuyCNYrztIJ9n64nlDV5ooY5D/rLsTpijv9Zd/8p qCRaXx7YypFcK6Wy6qKTeSP5BtFHfGnuuBYL3lo+WxGHWCXMU/oCqm+yCtGqwGgIf/k6azDuOzQ wefAzeUai8C0J8u4c35r8tUnKFXu9UJj/ElO57u6mN20v35l8pQ8qmD0NObYms3P0DdX7bqvG/u f3xfuTl/uoBMkhv9Qb1T7c3A8L3q9VuVBudrQO7Pi69MGX9rPh2t0yGEmDyVqVqefr0dKGdRD68 sFqAfU+QEXn2jA1LkLELoEPzgvuafz0kspSSJUpu3Yss/a5OmKXteglfoJi4GCtC11d3tMPgsSs aBZV/ILcMsYMd3sf0A6GersHGCvjO/wML96+ihBYNg8nP35 X-Received: by 2002:a05:6830:11d5:b0:7d7:39a9:4c1f with SMTP id 46e09a7af769-7d739a94d4emr4025551a34.28.1773106008565; Mon, 09 Mar 2026 18:26:48 -0700 (PDT) Received: from localhost.localdomain (108-212-132-20.lightspeed.irvnca.sbcglobal.net. [108.212.132.20]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7d7449b9e57sm3928395a34.22.2026.03.09.18.26.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Mar 2026 18:26:48 -0700 (PDT) From: Wesley Atwell To: edumazet@google.com, ncardwell@google.com, davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org, pabeni@redhat.com Cc: kuniyu@google.com, horms@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Wesley Atwell Subject: [PATCH] tcp: use WRITE_ONCE() for tsoffset in tcp_v6_connect() Date: Mon, 9 Mar 2026 19:26:04 -0600 Message-Id: <20260310012604.145661-1-atwellwea@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Commit dd23c9f1e8d5 ("tcp: annotate data-races around tp->tsoffset") updated do_tcp_getsockopt() to read tp->tsoffset with READ_ONCE() for TCP_TIMESTAMP because another CPU may change it concurrently. tcp_v6_connect() still stores tp->tsoffset with a plain write. That store runs under lock_sock() via inet_stream_connect(), but the socket lock does not serialize a concurrent getsockopt(TCP_TIMESTAMP) from another task sharing the socket. Use WRITE_ONCE() for the tcp_v6_connect() store so the connect-time writer matches the lockless TCP_TIMESTAMP reader. This also makes the IPv6 path consistent with tcp_v4_connect(). Signed-off-by: Wesley Atwell Reviewed-by: Eric Dumazet Reviewed-by: Jiayuan Chen --- net/ipv6/tcp_ipv6.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index bb09d5ccf599..ba7cd7d3d4da 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -325,7 +325,7 @@ static int tcp_v6_connect(struct sock *sk, struct socka= ddr_unsized *uaddr, inet->inet_dport); if (!tp->write_seq) WRITE_ONCE(tp->write_seq, st.seq); - tp->tsoffset =3D st.ts_off; + WRITE_ONCE(tp->tsoffset, st.ts_off); } =20 if (tcp_fastopen_defer_connect(sk, &err)) --=20 2.34.1