lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220124183959.050250496@linuxfoundation.org>
Date:   Mon, 24 Jan 2022 19:42:23 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Tycho Andersen <tycho@...ho.pizza>,
        Linus Lüssing <linus.luessing@...3.blue>,
        Sven Eckelmann <sven@...fation.org>,
        Simon Wunderlich <sw@...onwunderlich.de>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 159/320] batman-adv: allow netlink usage in unprivileged containers

From: Linus Lüssing <linus.luessing@...3.blue>

[ 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@...tainer:~# batctl originators
  Error received: Operation not permitted
  root@...tainer:~# batctl orig_interval
  1000
  root@...tainer:~# batctl orig_interval 2000
  root@...tainer:~# 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 <tycho@...ho.pizza>
Signed-off-by: Linus Lüssing <linus.luessing@...3.blue>
Signed-off-by: Sven Eckelmann <sven@...fation.org>
Signed-off-by: Simon Wunderlich <sw@...onwunderlich.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 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



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ