[PATCH net-next] net: bridge: mst: Restrict info size queries to bridge ports

From: Tobias Waldekranz
Date: Tue Mar 22 2022 - 09:30:28 EST


Ensure that no bridge masters are ever considered for MST info
dumping. MST states are only supported on bridge ports, not bridge
masters - which br_mst_info_size relies on.

Fixes: 122c29486e1f ("net: bridge: mst: Support setting and reporting MST port states")
Signed-off-by: Tobias Waldekranz <tobias@xxxxxxxxxxxxxx>
---

It turns out that even with Eric's fix, the guard was not restrictive
enough. Sorry about all the noise around this.

net/bridge/br_netlink.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 204472449ec9..200ad05b296f 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -119,7 +119,7 @@ static size_t br_get_link_af_size_filtered(const struct net_device *dev,
/* Each VLAN is returned in bridge_vlan_info along with flags */
vinfo_sz += num_vlan_infos * nla_total_size(sizeof(struct bridge_vlan_info));

- if (vg && (filter_mask & RTEXT_FILTER_MST))
+ if (p && vg && (filter_mask & RTEXT_FILTER_MST))
vinfo_sz += br_mst_info_size(vg);

if (!(filter_mask & RTEXT_FILTER_CFM_STATUS))
--
2.25.1