[PATCH net-next 4/5] mptcp: allow privileged operations from user namespaces

From: Matthieu Baerts
Date: Tue Sep 06 2022 - 16:57:18 EST


From: Thomas Haller <thaller@xxxxxxxxxx>

GENL_ADMIN_PERM checks that the user has CAP_NET_ADMIN in the initial
namespace by calling netlink_capable(). Instead, use GENL_UNS_ADMIN_PERM
which uses netlink_ns_capable(). This checks that the caller has
CAP_NET_ADMIN in the current user namespace.

See also

commit 4a92602aa1cd ("openvswitch: allow management from inside user namespaces")

which introduced this mechanism. See also

commit 5617c6cd6f84 ("nl80211: Allow privileged operations from user namespaces")

which introduced this for nl80211.

Signed-off-by: Thomas Haller <thaller@xxxxxxxxxx>
Reviewed-by: Mat Martineau <mathew.j.martineau@xxxxxxxxxxxxxxx>
Signed-off-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx>
---
net/mptcp/pm_netlink.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 5e142c0c597a..afc98adf2746 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -2218,17 +2218,17 @@ static const struct genl_small_ops mptcp_pm_ops[] = {
{
.cmd = MPTCP_PM_CMD_ADD_ADDR,
.doit = mptcp_nl_cmd_add_addr,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_DEL_ADDR,
.doit = mptcp_nl_cmd_del_addr,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_FLUSH_ADDRS,
.doit = mptcp_nl_cmd_flush_addrs,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_GET_ADDR,
@@ -2238,7 +2238,7 @@ static const struct genl_small_ops mptcp_pm_ops[] = {
{
.cmd = MPTCP_PM_CMD_SET_LIMITS,
.doit = mptcp_nl_cmd_set_limits,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_GET_LIMITS,
@@ -2247,27 +2247,27 @@ static const struct genl_small_ops mptcp_pm_ops[] = {
{
.cmd = MPTCP_PM_CMD_SET_FLAGS,
.doit = mptcp_nl_cmd_set_flags,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_ANNOUNCE,
.doit = mptcp_nl_cmd_announce,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_REMOVE,
.doit = mptcp_nl_cmd_remove,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_SUBFLOW_CREATE,
.doit = mptcp_nl_cmd_sf_create,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_SUBFLOW_DESTROY,
.doit = mptcp_nl_cmd_sf_destroy,
- .flags = GENL_ADMIN_PERM,
+ .flags = GENL_UNS_ADMIN_PERM,
},
};

--
2.37.2