From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 248CAC11F66 for ; Tue, 6 Jul 2021 11:28:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1759561F41 for ; Tue, 6 Jul 2021 11:28:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235029AbhGFL3d (ORCPT ); Tue, 6 Jul 2021 07:29:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:55940 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233349AbhGFLWU (ORCPT ); Tue, 6 Jul 2021 07:22:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5539A61CD8; Tue, 6 Jul 2021 11:17:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625570274; bh=KOu7qrupT3Xq1MPcezUqH3okfRUfVTjKqiEIPZ1rfEU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YN/lNI0u9PIMQ+tLXGiql6tKPJFmBMLIwNUm+lCFvexBYRI+bztqiMjGM96JcIhTd YqO1XJvTYSha1a5EiBKbkMivpDEbnbA/4thf9fm3uAXKnvySUVfIM3gOKL4i11vqY7 2fRFL1fBPv2kqro/yQXN/aTcxD9j6x22ZJ4L0CX9SLsDW89gf1e1MsrBKi0HvAPxol xPwgezk1vd+Yfcvl2za9DUJZj+EyhJsdwkk87KB2KwHtw9IAkqzDaikKo07ksojlrj eJmdHHAQXaafuz6ysmKGAsUAyiIL9pVLcPFndwIxklnXwTpbiL5Dt30JPCX29o5Jfg KUwokFVr1tS2A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Martynas Pumputis , Lorenz Bauer , Eric Dumazet , "David S . Miller" , Sasha Levin , linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.13 167/189] net: retrieve netns cookie via getsocketopt Date: Tue, 6 Jul 2021 07:13:47 -0400 Message-Id: <20210706111409.2058071-167-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210706111409.2058071-1-sashal@kernel.org> References: <20210706111409.2058071-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Martynas Pumputis [ Upstream commit e8b9eab99232c4e62ada9d7976c80fd5e8118289 ] It's getting more common to run nested container environments for testing cloud software. One of such examples is Kind [1] which runs a Kubernetes cluster in Docker containers on a single host. Each container acts as a Kubernetes node, and thus can run any Pod (aka container) inside the former. This approach simplifies testing a lot, as it eliminates complicated VM setups. Unfortunately, such a setup breaks some functionality when cgroupv2 BPF programs are used for load-balancing. The load-balancer BPF program needs to detect whether a request originates from the host netns or a container netns in order to allow some access, e.g. to a service via a loopback IP address. Typically, the programs detect this by comparing netns cookies with the one of the init ns via a call to bpf_get_netns_cookie(NULL). However, in nested environments the latter cannot be used given the Kubernetes node's netns is outside the init ns. To fix this, we need to pass the Kubernetes node netns cookie to the program in a different way: by extending getsockopt() with a SO_NETNS_COOKIE option, the orchestrator which runs in the Kubernetes node netns can retrieve the cookie and pass it to the program instead. Thus, this is following up on Eric's commit 3d368ab87cf6 ("net: initialize net->net_cookie at netns setup") to allow retrieval via SO_NETNS_COOKIE. This is also in line in how we retrieve socket cookie via SO_COOKIE. [1] https://kind.sigs.k8s.io/ Signed-off-by: Lorenz Bauer Signed-off-by: Martynas Pumputis Cc: Eric Dumazet Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- arch/alpha/include/uapi/asm/socket.h | 2 ++ arch/mips/include/uapi/asm/socket.h | 2 ++ arch/parisc/include/uapi/asm/socket.h | 2 ++ arch/sparc/include/uapi/asm/socket.h | 2 ++ include/uapi/asm-generic/socket.h | 2 ++ net/core/sock.c | 7 +++++++ 6 files changed, 17 insertions(+) diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h index 57420356ce4c..6b3daba60987 100644 --- a/arch/alpha/include/uapi/asm/socket.h +++ b/arch/alpha/include/uapi/asm/socket.h @@ -127,6 +127,8 @@ #define SO_PREFER_BUSY_POLL 69 #define SO_BUSY_POLL_BUDGET 70 +#define SO_NETNS_COOKIE 71 + #if !defined(__KERNEL__) #if __BITS_PER_LONG == 64 diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h index 2d949969313b..cdf404a831b2 100644 --- a/arch/mips/include/uapi/asm/socket.h +++ b/arch/mips/include/uapi/asm/socket.h @@ -138,6 +138,8 @@ #define SO_PREFER_BUSY_POLL 69 #define SO_BUSY_POLL_BUDGET 70 +#define SO_NETNS_COOKIE 71 + #if !defined(__KERNEL__) #if __BITS_PER_LONG == 64 diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h index f60904329bbc..5b5351cdcb33 100644 --- a/arch/parisc/include/uapi/asm/socket.h +++ b/arch/parisc/include/uapi/asm/socket.h @@ -119,6 +119,8 @@ #define SO_PREFER_BUSY_POLL 0x4043 #define SO_BUSY_POLL_BUDGET 0x4044 +#define SO_NETNS_COOKIE 0x4045 + #if !defined(__KERNEL__) #if __BITS_PER_LONG == 64 diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index 848a22fbac20..92675dc380fa 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -120,6 +120,8 @@ #define SO_PREFER_BUSY_POLL 0x0048 #define SO_BUSY_POLL_BUDGET 0x0049 +#define SO_NETNS_COOKIE 0x0050 + #if !defined(__KERNEL__) diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index 4dcd13d097a9..d588c244ec2f 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -122,6 +122,8 @@ #define SO_PREFER_BUSY_POLL 69 #define SO_BUSY_POLL_BUDGET 70 +#define SO_NETNS_COOKIE 71 + #if !defined(__KERNEL__) #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__)) diff --git a/net/core/sock.c b/net/core/sock.c index 946888afef88..2003c5ebb4c2 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1622,6 +1622,13 @@ int sock_getsockopt(struct socket *sock, int level, int optname, v.val = sk->sk_bound_dev_if; break; + case SO_NETNS_COOKIE: + lv = sizeof(u64); + if (len != lv) + return -EINVAL; + v.val64 = sock_net(sk)->net_cookie; + break; + default: /* We implement the SO_SNDLOWAT etc to not be settable * (1003.1g 7). -- 2.30.2