From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 EC920340413 for ; Fri, 29 May 2026 19:39:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780083586; cv=none; b=SZszwVWTixFEeM0ntFYBK4EACIf7BsDzEavsW61bfqhvrN5TCDksQFotPlWj5i/uVxRq0szEM1TbECZShNvxNqhKldzka5pEaZleUjA1VSWcwAj41T8xgoZlTpUCZatOAanJ313VFHr8TXMqy0vynAOqcevWSjzI2H+5FY0Kxgw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780083586; c=relaxed/simple; bh=D5LevdIMh6QHRwUW3ZUwKINvHPpDAnk/8ciQktkkn6M=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=p1GS/jHJMNyn5R9tADFmcGBuvkhtSBDZUhUlN2nfwyMfLdujDObRPI30ie+d8OMl7Ew6ErHT9V+B9nGS7AVWU3RQ/Hbf4Q8px8DLwHJgX0cl30i5cCuOifxbbaLUkM5R+onWenwY+HAiHi7NkkoTHkVNp06jac945kL/1B7Qtvc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--kuniyu.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Wn3kLz2w; arc=none smtp.client-ip=209.85.215.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--kuniyu.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Wn3kLz2w" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-c827bda2e60so8416397a12.3 for ; Fri, 29 May 2026 12:39:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780083584; x=1780688384; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=UvNbPePsMJ4Tw9B574ZFI9cvexcAYVtdVUU7rlslHbE=; b=Wn3kLz2wCRD9VZ8bZLJGPisAvI/jBNWDioxulHo3L2hb04ipYkPHxZfRNylaB2CiwY SId1PeaDMhp3Vo6fBdyxJ60nvvHcmbR/GgPtjH82g1cB/2Jdas7u3OMVteabldMLOCRK qkh5eriXnJ97vMG3uz15plD1oWLA2EouInSlG+ZZmRwsVc6G1ix7YO1weeoF4L8GHxw/ Mac1PvsKJa11AlqIHCUvglYW1flxmzNf5vLlkmTfjI4TbbTLuXjLrhtyOIy9VBBZJGYv vDFgRys/AaJDxHb8VyTzMaPWUqqu9RfCagvMWWSQhYfYmuqD1xfh6mZ6ulUfq7WbUmTf CYaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780083584; x=1780688384; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=UvNbPePsMJ4Tw9B574ZFI9cvexcAYVtdVUU7rlslHbE=; b=bOH9TPm/IY327eClE5kQaouI3eL8ibhSA9HDelXtpNUiwSNUx+2vI23Qc5/eDYxTRJ ob+RYtVT4LI3Xo1qlCWtR22ZUcwJAryJntdlB/v6HrEemmgfimvmzOP41PP+Hw976p8y 3w+n+qVtge87shdePSBFaOuCYIqyVjSreS6gXtkcv9lQMVyVs9/pQtlIn7pXgNwCavMI QQehsD7D5GjhDHQ4+b2EAXqB7GQRkLPzem+yrIJcAlt+TPUmnvcGg3oOPBugfS0cHo/+ nBRNJqNSOjIAiegdP7oRdMdcw5L0sD+ChuEMOL8h5/fw50KrgIcdTFIV39Jb0mwOW/db WEzQ== X-Forwarded-Encrypted: i=1; AFNElJ9WOUwI8YpIgQjmsA92oqOynyHyyhlBCYLD8WmkNtJ+SduYz0UsNb7qz+JRF0ZALZBJZ9sTqFQ=@vger.kernel.org X-Gm-Message-State: AOJu0YzdrIMB4lHzhTxRdja8nAH9ICx5Ph/ux8O5vpYiE/2RPYDdrxGK jyMXzhffLI0MKyX0ByNYai6bFeG+CcHW8yancf+5ZKK/Co8qZC5vqpVyxZzZG0aH90cCNtMWICR Mui1Bxw== X-Received: from pfbjf8.prod.google.com ([2002:a05:6a00:6e48:b0:835:20c7:97df]) (user=kuniyu job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:aa8c:b0:841:5701:16d9 with SMTP id d2e1a72fcca58-842257ea1ecmr821314b3a.50.1780083583896; Fri, 29 May 2026 12:39:43 -0700 (PDT) Date: Fri, 29 May 2026 19:39:23 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.54.0.823.g6e5bcc1fc9-goog Message-ID: <20260529193941.3897256-1-kuniyu@google.com> Subject: [PATCH v1 net] net: Annotate sk->sk_write_space() for UDP SOCKMAP. From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn Cc: Simon Horman , Lorenz Bauer , Kuniyuki Iwashima , Kuniyuki Iwashima , netdev@vger.kernel.org Content-Type: text/plain; charset="UTF-8" UDP TX skb->destructor() is sock_wfree(), and UDP holds lock_sock() only for UDP_CORK / MSG_MORE sendmsg(). Otherwise, sk->sk_write_space() may be read locklessly while SOCKMAP rewrites sk->sk_write_space(). Let's use WRITE_ONCE() and READ_ONCE() for sk->sk_write_space(). Note that the write side is annotated by commit 2ef2b20cf4e0 ("net: annotate data-races around sk->sk_{data_ready,write_space}"). Fixes: 7b98cd42b049 ("bpf: sockmap: Add UDP support") Signed-off-by: Kuniyuki Iwashima --- net/core/sock.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index b37b664b6eb9..d097025c116a 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2676,8 +2676,12 @@ void sock_wfree(struct sk_buff *skb) int old; if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { + void (*sk_write_space)(struct sock *sk); + + sk_write_space = READ_ONCE(sk->sk_write_space); + if (sock_flag(sk, SOCK_RCU_FREE) && - sk->sk_write_space == sock_def_write_space) { + sk_write_space == sock_def_write_space) { rcu_read_lock(); free = __refcount_sub_and_test(len, &sk->sk_wmem_alloc, &old); @@ -2693,7 +2697,7 @@ void sock_wfree(struct sk_buff *skb) * after sk_write_space() call */ WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); - sk->sk_write_space(sk); + sk_write_space(sk); len = 1; } /* -- 2.54.0.823.g6e5bcc1fc9-goog