RE: [PATCH net] tipc: require admin privileges for TIPCv2 mutators

[Tung Quang Nguyen]

>Subject: [PATCH net] tipc: require admin privileges for TIPCv2 mutators
>
>TIPCv2 registers its generic-netlink mutating commands without permission
>flags. Generic netlink only checks CAP_NET_ADMIN when an operation carries
>GENL_ADMIN_PERM or GENL_UNS_ADMIN_PERM, so callers without
>CAP_NET_ADMIN can invoke these setters.
>
>This allows an unprivileged caller to change TIPC control-plane state, including
>bearer, link, network, monitor, peer and crypto-key state.
>TIPC_NL_MEDIA_SET is broader because it updates the shared media defaults
>returned by tipc_media_find(), including UDP MTU, priority, tolerance and
>window values, which can affect later bearer setup.
>
>Require CAP_NET_ADMIN for all TIPCv2 mutators. Use
>GENL_UNS_ADMIN_PERM for network-namespace scoped state, matching the
>legacy compat path and normal netns administration semantics. Use
>GENL_ADMIN_PERM for TIPC_NL_MEDIA_SET because it mutates global media
>defaults rather than state owned only by the target net namespace.

A similar patch has been submitted using the same AI:
https://patchwork.kernel.org/project/netdevbpf/patch/20260602133555.769727-2-michael.bommarito@xxxxxxxxx/

Your patch suggests using GENL_ADMIN_PERM while above patch does not.
Did AI suggest using GENL_ADMIN_PERM or you suggested it yourself ?

>
>Fixes: 0655f6a8635b ("tipc: add bearer disable/enable to new netlink api")
>Assisted-by: Codex:gpt-5.5-cyber-preview
>Signed-off-by: Dominik 'Disconnect3d' Czarnota
><dominik.czarnota@xxxxxxxxxxxxxxx>
>---
> net/tipc/netlink.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
>diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c index
>1a9a5bdaccf4..5bbe134284ac 100644
>--- a/net/tipc/netlink.c
>+++ b/net/tipc/netlink.c
>@@ -152,11 +152,13 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_BEARER_DISABLE,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_bearer_disable,
> 	},
> 	{
> 		.cmd	= TIPC_NL_BEARER_ENABLE,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_bearer_enable,
> 	},
> 	{
>@@ -168,11 +170,13 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_BEARER_ADD,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_bearer_add,
> 	},
> 	{
> 		.cmd	= TIPC_NL_BEARER_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_bearer_set,
> 	},
> 	{
>@@ -197,11 +201,13 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_LINK_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_node_set_link,
> 	},
> 	{
> 		.cmd	= TIPC_NL_LINK_RESET_STATS,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit   = tipc_nl_node_reset_link_stats,
> 	},
> 	{
>@@ -213,6 +219,7 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_MEDIA_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_ADMIN_PERM,
> 		.doit	= tipc_nl_media_set,
> 	},
> 	{
>@@ -228,6 +235,7 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_NET_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_net_set,
> 	},
> 	{
>@@ -238,6 +246,7 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_MON_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_node_set_monitor,
> 	},
> 	{
>@@ -255,6 +264,7 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_PEER_REMOVE,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_peer_rm,
> 	},
> #ifdef CONFIG_TIPC_MEDIA_UDP
>@@ -269,11 +279,13 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
> 	{
> 		.cmd	= TIPC_NL_KEY_SET,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_node_set_key,
> 	},
> 	{
> 		.cmd	= TIPC_NL_KEY_FLUSH,
> 		.validate = GENL_DONT_VALIDATE_STRICT |
>GENL_DONT_VALIDATE_DUMP,
>+		.flags	= GENL_UNS_ADMIN_PERM,
> 		.doit	= tipc_nl_node_flush_key,
> 	},
> #endif