From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yx1-f73.google.com (mail-yx1-f73.google.com [74.125.224.73]) (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 D2E283AE701 for ; Wed, 25 Feb 2026 13:20:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.224.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772025625; cv=none; b=oWActFM8IZrPU4ghTh9c0hL4x3oJrXlaqBwfIG5HB0ZNQ9OPOUXCCu3AdulDE34xG2kowMZSHqoTWr1TYirAaOkYWCY7a0YpJ4hCHJe4sm+z5IzexsFGCOQdFrmDPvfQtUS2SPZ9ybmQL2gSYkAh5S2iSdIi10u3UtSZHjlbNeI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772025625; c=relaxed/simple; bh=dWkOdHUNZY084evNatRVHBp93SP9Ud6vhumdrqM0qYw=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=ZprPvHcOxbzP+qUtpUMkq6OcqavJ+GIu+HVdrKwX1JzZdtQBbO3cUKOcqmhSuGPiFox4l+hqJxO9MCabkYS2jRfp6Ueq5XcbaiuHrQqtcoSC6pUJI+//9sqbZCNLLqDRmRMNFylUzXM4eeXBC6Dg4vkpUhM1Scz0HdvHMMIMB28= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=cO6MYkoO; arc=none smtp.client-ip=74.125.224.73 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--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="cO6MYkoO" Received: by mail-yx1-f73.google.com with SMTP id 956f58d0204a3-64956932a51so8321472d50.0 for ; Wed, 25 Feb 2026 05:20:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1772025623; x=1772630423; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=+IhwFnC60BkZSlrOC/ALdUxYIAf2cwE+9LjagsdzVp8=; b=cO6MYkoOXx2KGXSjTTP9BEAAz8ELdZtwu3Z8UGIcGqZytlou56ifqnnFs7zeNBFw79 R5rsrTit5M5QP9ycOEOECgePI96le9IKADfkqWq6AMsGXeR1WYkCVxWgYgk4aHUwwt1q A7a4xsVY1t6p4icBCp5r3IOIU7TltZ68XKYDxG9Jw9byvwywdUUdaGZ/wxzZHAT3ZqaX tMR1/7MX5XX7Ms/7tHqOvS0cHnH1HPkEuMtBqgTsx0xAhdQXaxkSvp9Fz5buVQYmP9Cp 0MMIscL0P7vgHgbhmhQFCSEXyU2M/eM4zB3GvtERZKAyy4blAffTAlRKrYCRmJXVxLzb U2qQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772025623; x=1772630423; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=+IhwFnC60BkZSlrOC/ALdUxYIAf2cwE+9LjagsdzVp8=; b=EfKUrKPxtBlZX7PUpGGkO6lAZ1q7hajLU2ZoCBhswHsz6CMZjCGl8vaY+uA2my/Vts 2QRLmfy0/uICBAFOV05UHNmPgha9wJSJhljEtJGvpW23QGtC3jy1zMNEJ2uYFPvAGVDl kNSuRdi43iBGyy87tNjbkTPcOpO92dGiRrf2RoMh6dQhqJYtjWWyhZMwJP0FoYDOaFlV UVwhJZnrXcwaV6v5E5JE8QGWoi6gtJGT9IBGnLqA4LKJe8+omvQ10czYKZd4z6rjOL7H Qki7t7eHIKDjjL9HZ63qUcOc9EJ4UX0UVPzyVRvZTh/POqw41MYXjtF8eIlYS8umWefD Ppzw== X-Gm-Message-State: AOJu0YwGLE7ApuNTt+GJmXntgGjcGdFW2RdK5OCG3TYOIGrFOubfOd9g 5qoxBTL2dST6cfhNuLKT3hYtdYrjmfWSqN69DStNkt9FLjo/EAE9+388ITyt+viiB8ustQo3k6y WaE0fAGuhAd/kFw== X-Received: from yxyb18.prod.google.com ([2002:a05:690e:1d2:b0:646:e5d7:6a2a]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a53:cd86:0:b0:64a:d9b3:6ef3 with SMTP id 956f58d0204a3-64c787d6ed6mr10402222d50.6.1772025622596; Wed, 25 Feb 2026 05:20:22 -0800 (PST) Date: Wed, 25 Feb 2026 13:20:19 +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 2.53.0.414.gf7e9f6c205-goog Message-ID: <20260225132019.1103701-1-edumazet@google.com> Subject: [PATCH v2 nf-next] netfilter: nf_log_syslog: no longer acquire sk_callback_lock in nf_log_dump_sk_uid_gid() From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni , Pablo Neira Ayuso , Florian Westphal Cc: netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" After commit 983512f3a87f ("net: Drop the lock in skb_may_tx_timestamp()") from Sebastian Andrzej Siewior, apply the same logic in nf_log_dump_sk_uid_gid() to avoid touching sk_callback_lock. Signed-off-by: Eric Dumazet Reviewed-by: Florian Westphal --- net/netfilter/nf_log_syslog.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/net/netfilter/nf_log_syslog.c b/net/netfilter/nf_log_syslog.c index 41503847d9d7fb21824fabb1b57b45f2622b9310..0507d67cad27530dd814aabaf806fdcd3583fe01 100644 --- a/net/netfilter/nf_log_syslog.c +++ b/net/netfilter/nf_log_syslog.c @@ -165,18 +165,26 @@ static struct nf_logger nf_arp_logger __read_mostly = { static void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m, struct sock *sk) { + const struct socket *sock; + const struct file *file; + if (!sk || !sk_fullsock(sk) || !net_eq(net, sock_net(sk))) return; - read_lock_bh(&sk->sk_callback_lock); - if (sk->sk_socket && sk->sk_socket->file) { - const struct cred *cred = sk->sk_socket->file->f_cred; + /* The sk pointer remains valid as long as the skb is. The sk_socket and + * file pointer may become NULL if the socket is closed. Both structures + * (including file->cred) are RCU freed which means they can be accessed + * within a RCU read section. + */ + sock = READ_ONCE(sk->sk_socket); + file = sock ? READ_ONCE(sock->file) : NULL; + if (file) { + const struct cred *cred = file->f_cred; nf_log_buf_add(m, "UID=%u GID=%u ", from_kuid_munged(&init_user_ns, cred->fsuid), from_kgid_munged(&init_user_ns, cred->fsgid)); } - read_unlock_bh(&sk->sk_callback_lock); } static noinline_for_stack int -- 2.53.0.414.gf7e9f6c205-goog