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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64882C43217 for ; Tue, 18 Jan 2022 02:27:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343545AbiARC1s (ORCPT ); Mon, 17 Jan 2022 21:27:48 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:42510 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245410AbiARCZf (ORCPT ); Mon, 17 Jan 2022 21:25:35 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4C06360A6B; Tue, 18 Jan 2022 02:25:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F4AFC36AE3; Tue, 18 Jan 2022 02:25:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642472734; bh=NrDQkO4I+cVBZBVA1n3ItY4WmFP9x95zh+C06Zuohno=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=btvQ2z+j/RpBiFS5AGd3UzcR/lEXwg1sUmLnybAaBI9/yAWICQmYHEg9pY4nSpXzQ v1MCSeUV26Ac4BNArAalpreHUgkrIFp6UvZjqKXy4Cw7wRshaicWC8WTx/HlMmCv91 i8CipWsXQbU6J7+XZD2B8E7Ez17+s83/koVib4f0Am0SpiwOOKgEuO0BkFlB4GPOJv aaVUfpRiIQw5mWn6GorSjAfnD1ubx0ZmY9LWV14saW4tJKf10UEn/2/26Gt6wA/ma0 vDF5WBcaVWshXb+QIORQjmPAMbwrp3H2Fljva+K9EakMxH4Sxxqn1G0M6e6qzSlyK0 0VosqtWjkcTDg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: xu xin , Zeal Robot , Joanne Koong , "David S . Miller" , Sasha Levin , kuba@kernel.org, daniel@iogearbox.net, dsahern@kernel.org, roopa@nvidia.com, edumazet@google.com, chinagar@codeaurora.org, yajun.deng@linux.dev, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.16 118/217] net: Enable neighbor sysctls that is save for userns root Date: Mon, 17 Jan 2022 21:18:01 -0500 Message-Id: <20220118021940.1942199-118-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118021940.1942199-1-sashal@kernel.org> References: <20220118021940.1942199-1-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: xu xin [ Upstream commit 8c8b7aa7fb0cf9e1cc9204e6bc6e1353b8393502 ] Inside netns owned by non-init userns, sysctls about ARP/neighbor is currently not visible and configurable. For the attributes these sysctls correspond to, any modifications make effects on the performance of networking(ARP, especilly) only in the scope of netns, which does not affect other netns. Actually, some tools via netlink can modify these attribute. iproute2 is an example. see as follows: $ unshare -ur -n $ cat /proc/sys/net/ipv4/neigh/lo/retrans_time cat: can't open '/proc/sys/net/ipv4/neigh/lo/retrans_time': No such file or directory $ ip ntable show dev lo inet arp_cache dev lo refcnt 1 reachable 19494 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 1000 inet6 ndisc_cache dev lo refcnt 1 reachable 42394 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 0 $ ip ntable change name arp_cache dev retrans 2000 inet arp_cache dev lo refcnt 1 reachable 22917 base_reachable 30000 retrans 2000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 1000 inet6 ndisc_cache dev lo refcnt 1 reachable 35524 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 0 Reported-by: Zeal Robot Signed-off-by: xu xin Acked-by: Joanne Koong Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/neighbour.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/net/core/neighbour.c b/net/core/neighbour.c index dda12fbd177ba..559928a1defb4 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -3770,10 +3770,6 @@ int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, neigh_proc_base_reachable_time; } - /* Don't export sysctls to unprivileged users */ - if (neigh_parms_net(p)->user_ns != &init_user_ns) - t->neigh_vars[0].procname = NULL; - switch (neigh_parms_family(p)) { case AF_INET: p_name = "ipv4"; -- 2.34.1