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 A8615C433EF for ; Tue, 18 Jan 2022 03:47:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353683AbiARDq5 (ORCPT ); Mon, 17 Jan 2022 22:46:57 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:54372 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347190AbiARCkz (ORCPT ); Mon, 17 Jan 2022 21:40:55 -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 DDC0D611D6; Tue, 18 Jan 2022 02:40:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00453C36AF2; Tue, 18 Jan 2022 02:40:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642473654; bh=Y3fmQ1Gr9y2ZSWkBNN6dTmaQIXWW9+9Nx7kmY3MGb2A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KSJWLeI+ExXnElqQf9aSIhL77VBUT7ELYu+AWG4FCzCQTnDurt9SVPYqIBwIcvA5j LkyU7aG7zA9OIS3dU8rsAB1lnxaUTG6LDf5TmH91o3oxI7VgtB/ptiA2Splfh3JhmZ nZwZ9b7ZP2NwpPGILvYgJLPUwmIWJNQ2G8ffNKfDPbQgFRg0WuFuaJq1JuIpJZEGoi ExqqWfHajv0bYjADqPMLdp0VO+w0wPhMrPz7eeyiCAnXo4p8nJGWmvF7aw9oXhzYhl i9rru6HQ5sS1HMp7lvS8ihJSkEqBplmNClC0CLNNLfM2yyRQkC6BK6xRpadqWIbUhh Rmh5MHiKaYHqg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Linus=20L=C3=BCssing?= , Tycho Andersen , Sven Eckelmann , Simon Wunderlich , Sasha Levin , mareklindner@neomailbox.ch, a@unstable.cc, davem@davemloft.net, kuba@kernel.org, b.a.t.m.a.n@lists.open-mesh.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.10 013/116] batman-adv: allow netlink usage in unprivileged containers Date: Mon, 17 Jan 2022 21:38:24 -0500 Message-Id: <20220118024007.1950576-13-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024007.1950576-1-sashal@kernel.org> References: <20220118024007.1950576-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Linus Lüssing [ Upstream commit 9057d6c23e7388ee9d037fccc9a7bc8557ce277b ] Currently, creating a batman-adv interface in an unprivileged LXD container and attaching secondary interfaces to it with "ip" or "batctl" works fine. However all batctl debug and configuration commands fail: root@container:~# batctl originators Error received: Operation not permitted root@container:~# batctl orig_interval 1000 root@container:~# batctl orig_interval 2000 root@container:~# batctl orig_interval 1000 To fix this change the generic netlink permissions from GENL_ADMIN_PERM to GENL_UNS_ADMIN_PERM. This way a batman-adv interface is fully maintainable as root from within a user namespace, from an unprivileged container. All except one batman-adv netlink setting are per interface and do not leak information or change settings from the host system and are therefore save to retrieve or modify as root from within an unprivileged container. "batctl routing_algo" / BATADV_CMD_GET_ROUTING_ALGOS is the only exception: It provides the batman-adv kernel module wide default routing algorithm. However it is read-only from netlink and an unprivileged container is still not allowed to modify /sys/module/batman_adv/parameters/routing_algo. Instead it is advised to use the newly introduced "batctl if create routing_algo RA_NAME" / IFLA_BATADV_ALGO_NAME to set the routing algorithm on interface creation, which already works fine in an unprivileged container. Cc: Tycho Andersen Signed-off-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin --- net/batman-adv/netlink.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index c7a55647b520e..121459704b069 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -1361,21 +1361,21 @@ static const struct genl_small_ops batadv_netlink_ops[] = { { .cmd = BATADV_CMD_TP_METER, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .doit = batadv_netlink_tp_meter_start, .internal_flags = BATADV_FLAG_NEED_MESH, }, { .cmd = BATADV_CMD_TP_METER_CANCEL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .doit = batadv_netlink_tp_meter_cancel, .internal_flags = BATADV_FLAG_NEED_MESH, }, { .cmd = BATADV_CMD_GET_ROUTING_ALGOS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_algo_dump, }, { @@ -1390,68 +1390,68 @@ static const struct genl_small_ops batadv_netlink_ops[] = { { .cmd = BATADV_CMD_GET_TRANSTABLE_LOCAL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_tt_local_dump, }, { .cmd = BATADV_CMD_GET_TRANSTABLE_GLOBAL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_tt_global_dump, }, { .cmd = BATADV_CMD_GET_ORIGINATORS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_orig_dump, }, { .cmd = BATADV_CMD_GET_NEIGHBORS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_hardif_neigh_dump, }, { .cmd = BATADV_CMD_GET_GATEWAYS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_gw_dump, }, { .cmd = BATADV_CMD_GET_BLA_CLAIM, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_bla_claim_dump, }, { .cmd = BATADV_CMD_GET_BLA_BACKBONE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_bla_backbone_dump, }, { .cmd = BATADV_CMD_GET_DAT_CACHE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_dat_cache_dump, }, { .cmd = BATADV_CMD_GET_MCAST_FLAGS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .dumpit = batadv_mcast_flags_dump, }, { .cmd = BATADV_CMD_SET_MESH, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .doit = batadv_netlink_set_mesh, .internal_flags = BATADV_FLAG_NEED_MESH, }, { .cmd = BATADV_CMD_SET_HARDIF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .doit = batadv_netlink_set_hardif, .internal_flags = BATADV_FLAG_NEED_MESH | BATADV_FLAG_NEED_HARDIF, @@ -1467,7 +1467,7 @@ static const struct genl_small_ops batadv_netlink_ops[] = { { .cmd = BATADV_CMD_SET_VLAN, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, - .flags = GENL_ADMIN_PERM, + .flags = GENL_UNS_ADMIN_PERM, .doit = batadv_netlink_set_vlan, .internal_flags = BATADV_FLAG_NEED_MESH | BATADV_FLAG_NEED_VLAN, -- 2.34.1