[PATCH] ipvs: allow netlink configuration from non-initial user namespace

[Michael Weiß <michael.weiss@xxxxxxxxxxxxxxxxxxx>]

Configuring ipvs in a non-initial user namespace using the genl
netlink interface, e.g., by 'ipvsadm' is currently resulting in an
'-EPERM'. This is due to the use of GENL_ADMIN_PERM flag in
'ip_vs_ctl.c'.

Similarly to other genl interfaces, we switch to the use of
GENL_UNS_ADMIN_PERM flag which allows connection from non-initial
user namespace. Thus, it would be feasible to configure ipvs using
the genl interface also from within an unprivileged system container.

Since adding of new services and new dests are triggered from
userspace, accounting for the corresponding memory allocations in
ip_vs_new_dest() and ip_vs_add_service() is activated.

We tested this by simply running some samples from "man ipvsadm"
within an unprivileged user namespaced system container in GyroidOS.
Further, we successfully passed an adapted version of the ipvs
selftest in 'tools/testing/selftests/netfilter/ipvs.sh' using
preliminary created network namespaces from unprivileged GyroidOS
containers.

Signed-off-by: Michael Weiß <michael.weiss@xxxxxxxxxxxxxxxxxxx>
---
 net/netfilter/ipvs/ip_vs_ctl.c | 36 +++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 143a341bbc0a..d39120c64207 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -1080,7 +1080,7 @@ ip_vs_new_dest(struct ip_vs_service *svc, struct 
ip_vs_dest_user_kern *udest)
                        return -EINVAL;
        }
 
-       dest = kzalloc(sizeof(struct ip_vs_dest), GFP_KERNEL);
+       dest = kzalloc(sizeof(struct ip_vs_dest), GFP_KERNEL_ACCOUNT);
        if (dest == NULL)
                return -ENOMEM;
 
@@ -1421,7 +1421,7 @@ ip_vs_add_service(struct netns_ipvs *ipvs, struct 
ip_vs_service_user_kern *u,
                ret_hooks = ret;
        }
 
-       svc = kzalloc(sizeof(struct ip_vs_service), GFP_KERNEL);
+       svc = kzalloc(sizeof(struct ip_vs_service), GFP_KERNEL_ACCOUNT);
        if (svc == NULL) {
                IP_VS_DBG(1, "%s(): no memory\n", __func__);
                ret = -ENOMEM;
@@ -4139,98 +4139,98 @@ static const struct genl_small_ops ip_vs_genl_ops[] = {
        {
                .cmd    = IPVS_CMD_NEW_SERVICE,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_SET_SERVICE,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_DEL_SERVICE,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_GET_SERVICE,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_get_cmd,
                .dumpit = ip_vs_genl_dump_services,
        },
        {
                .cmd    = IPVS_CMD_NEW_DEST,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_SET_DEST,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_DEL_DEST,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_GET_DEST,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .dumpit = ip_vs_genl_dump_dests,
        },
        {
                .cmd    = IPVS_CMD_NEW_DAEMON,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_daemon,
        },
        {
                .cmd    = IPVS_CMD_DEL_DAEMON,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_daemon,
        },
        {
                .cmd    = IPVS_CMD_GET_DAEMON,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .dumpit = ip_vs_genl_dump_daemons,
        },
        {
                .cmd    = IPVS_CMD_SET_CONFIG,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_GET_CONFIG,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_get_cmd,
        },
        {
                .cmd    = IPVS_CMD_GET_INFO,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_get_cmd,
        },
        {
                .cmd    = IPVS_CMD_ZERO,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
        {
                .cmd    = IPVS_CMD_FLUSH,
                .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-               .flags  = GENL_ADMIN_PERM,
+               .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ip_vs_genl_set_cmd,
        },
 };
-- 
2.39.2