From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f54.google.com (mail-wr1-f54.google.com [209.85.221.54]) (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 57772177998 for ; Tue, 17 Sep 2024 16:04:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726589042; cv=none; b=GZBDFBLVUlExxUZowcCqgu4cZM7q27hcWu4voQu4X55YUDqxmOwNjQjYzf1qViq/e/zTrIs7YZl0SCvpAiPEtOv/AMOLcyW5UIwq5WzWUrE9GZlLb+PQEPL89zoalHOwp2REV7pIQkj9NaixTznqnANaUKSsQGG5ANVrKzdzO9s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726589042; c=relaxed/simple; bh=0PuAepZP1sMeQLDW26baLJXMCFGkoiK4j9E2aYYgQd4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VnUQ6dA9CIs5MnxI8cY4oMZJC2VGYHKB/HVX3LqnKyaZ6ori1K4Ck1S1Eb4e1w8g3EsgZBdoKvQxaL20JEZb3MHna/S/JU5TREgwlGJ40YbEiNiJMnAVfmEPgG1qggLZ04YOhzL4C8GqYpV0UAfsAQNWbwSDjkZGJ5hr15sFdMQ= 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=PrtR+7V3; arc=none smtp.client-ip=209.85.221.54 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="PrtR+7V3" Received: by mail-wr1-f54.google.com with SMTP id ffacd0b85a97d-374c7d14191so4291033f8f.0 for ; Tue, 17 Sep 2024 09:04:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google09082023; t=1726589039; x=1727193839; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=LUR6P1shZ3CKhHBcBU/pF/r4AHgnylMjyz2ZEJJwzZ8=; b=PrtR+7V36+bdtIYbt8jGPfg4Fq8iv+OgbBEi38aTn4D6RkH8DfhftzDB2cEtbAE4ax +k/jjCPCysCZPACbPQfJBy/p6p4u6rvCvei6iQ3EVOPEvXyzVVaVz71FEWm3sCScFnRq rrMzAydd9aMzjGYlV2SCdhl1yzLnq4mMpnbBXzQC2E0nSq390cWSzGaw/Pup4STv8id+ +bwAVT7NVtcm/vckPd8eDZI6CJDtErwEpleVN0wcLp3BTPKYRT09KntmcI53BepXUSLX 5YXwB3WDlcOefY/LxhzP292n8RHzX+cYfj/GNqcuuUOY9C62/q6yrSLbVSU+fcBeI6zU la2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726589039; x=1727193839; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=LUR6P1shZ3CKhHBcBU/pF/r4AHgnylMjyz2ZEJJwzZ8=; b=H174wfcveHwBz0HvSgVkC141kb5OisHj2M1e/his7eNogQ3kOKx4IBKcOFK98by+27 1RljTun7F2J3JN8VQz4zQWKnhRGOQ1qmRU+pLieoHoa7JwSHWFm0LlXYgT+7nDJkAHnT txCJ+DhJCv2HIjaxuYWnpKvpE0z2AtDAtWEWaEfl+4g3RnojkylR9MST2Az3QQ/SCSne DaAqIxAYortXwmHDL0Q4OBh8zNDvNFtVy+R2E+w1jj1zzhA/lBbn7f0bnS1mdvCsbw2L zGL+0VXbNHq1F0q9iDhUATZqKUjc5m9tTAg3bls5P9+u6xNPPj8uCD1gD5HygZRhigXa izqg== X-Forwarded-Encrypted: i=1; AJvYcCWr7qahGKQoSctxOpztlBI3L+k56QBneYDLMOi52SASydHhYmiCpHG425LndNojOY2EDoyVqQHQAUYzW1IcC64=@vger.kernel.org X-Gm-Message-State: AOJu0Yw66aKgAd3yh9BZiAlkjVnrkVK/eE8W6RgiOikTAsxkfL1urtYn pqQA/r/WDKd9Hu7J8nWx+IX7Z6FwG1Mm6KQI2HjohSU7K1s9L5+8yUc/wmTimcs= X-Google-Smtp-Source: AGHT+IELMxfdNDwf5iSZU7vWhaPPmOrDY6BB7npKjG6qP2MIc5qwafIMfPL8kaxPB51/BUhX9+hYJA== X-Received: by 2002:a5d:4d0e:0:b0:374:cc89:174b with SMTP id ffacd0b85a97d-378a89e6471mr15397653f8f.4.1726589038490; Tue, 17 Sep 2024 09:03:58 -0700 (PDT) Received: from GHGHG14 ([2a09:bac5:50ca:432::6b:83]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42da22e733bsm106395475e9.22.2024.09.17.09.03.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Sep 2024 09:03:58 -0700 (PDT) Date: Tue, 17 Sep 2024 17:03:54 +0100 From: Tiago Lam To: Eric Dumazet Cc: "David S. Miller" , David Ahern , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Mykola Lysenko , Shuah Khan , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Jakub Sitnicki , kernel-team@cloudflare.com Subject: Re: [RFC PATCH 2/3] ipv6: Run a reverse sk_lookup on sendmsg. Message-ID: References: <20240913-reverse-sk-lookup-v1-0-e721ea003d4c@cloudflare.com> <20240913-reverse-sk-lookup-v1-2-e721ea003d4c@cloudflare.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Sat, Sep 14, 2024 at 01:40:25PM +0200, Eric Dumazet wrote: > On Fri, Sep 13, 2024 at 11:39 AM Tiago Lam wrote: > > > > This follows the same rationale provided for the ipv4 counterpart, where > > it now runs a reverse socket lookup when source addresses and/or ports > > are changed, on sendmsg, to check whether egress traffic should be > > allowed to go through or not. > > > > As with ipv4, the ipv6 sendmsg path is also extended here to support the > > IPV6_ORIGDSTADDR ancilliary message to be able to specify a source > > address/port. > > > > Suggested-by: Jakub Sitnicki > > Signed-off-by: Tiago Lam > > --- > > net/ipv6/datagram.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > > net/ipv6/udp.c | 8 ++++-- > > 2 files changed, 82 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c > > index fff78496803d..4214dda1c320 100644 > > --- a/net/ipv6/datagram.c > > +++ b/net/ipv6/datagram.c > > @@ -756,6 +756,27 @@ void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, > > } > > EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); > > > > +static inline bool reverse_sk_lookup(struct flowi6 *fl6, struct sock *sk, > > + struct in6_addr *saddr, __be16 sport) > > +{ > > + if (static_branch_unlikely(&bpf_sk_lookup_enabled) && > > + (saddr && sport) && > > + (ipv6_addr_cmp(&sk->sk_v6_rcv_saddr, saddr) || inet_sk(sk)->inet_sport != sport)) { > > + struct sock *sk_egress; > > + > > + bpf_sk_lookup_run_v6(sock_net(sk), IPPROTO_UDP, &fl6->daddr, fl6->fl6_dport, > > + saddr, ntohs(sport), 0, &sk_egress); > > + if (!IS_ERR_OR_NULL(sk_egress) && > > + atomic64_read(&sk_egress->sk_cookie) == atomic64_read(&sk->sk_cookie)) > > I do not understand this. > > 1) sk_cookie is not always initialized. It is done on demand, when/if > __sock_gen_cookie() was called. > > 2) if sk1 and sk2 share the same sk_cookie, then sk1 == sk2 ??? > > So why not simply testing sk_egress == sk ? > Oh, yes, you're right. I'll include this in my next revision, thanks.