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 7E7E4C433F5 for ; Tue, 18 Jan 2022 02:56:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238048AbiARC4J (ORCPT ); Mon, 17 Jan 2022 21:56:09 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:53250 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348089AbiARCov (ORCPT ); Mon, 17 Jan 2022 21:44:51 -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 ams.source.kernel.org (Postfix) with ESMTPS id 507BDB81255; Tue, 18 Jan 2022 02:44:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA476C36AEB; Tue, 18 Jan 2022 02:44:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642473888; bh=J50OZHN0zvd2GM4+rHZ4BtCzAMe4iStWevzL2oEi4hY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SNG4+y2v9oauG8Prlidiv8+aOZEGFYX7LT3oyq0tOYNMBEUHF2ulvplxnjM/HKoOr h8wWhvKNETznR4EwgTlSlGQGxu49wS2xO4WOV9Aw9Ri20oL8zz3E9WIht5BZZ6r5ME Iibit9vUkrFrc1nf65cno9M1nJkIbC7N1CDAJBliPzTa2wa5R1r7ZFUER2qvkqhc3Z Grndgt6fOnpo8oqTcbVLctq3/JylcMDgCOoKLWru5VfGFLj/nunj/56neuKc9BST0G 0Gu1cQhCV/6NX49m1FyJfOb9L1xrolSYrso1sm7M1bOprESxPwhkWVDO6NwoTlDO5s 8FPlTPfhsCUcw== 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 5.4 08/73] batman-adv: allow netlink usage in unprivileged containers Date: Mon, 17 Jan 2022 21:43:27 -0500 Message-Id: <20220118024432.1952028-8-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024432.1952028-1-sashal@kernel.org> References: <20220118024432.1952028-1-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: netdev@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 7e052d6f759b6..e59c5aa27ee0b 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -1351,21 +1351,21 @@ static const struct genl_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, }, { @@ -1380,68 +1380,68 @@ static const struct genl_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, @@ -1457,7 +1457,7 @@ static const struct genl_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