diff options
| author | Nikolay Aleksandrov <razor@blackwall.org> | 2025-11-05 13:19:19 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-11-06 07:32:17 -0800 |
| commit | ee87c63f9b2a418f698d79c2991347e31a7d2c27 (patch) | |
| tree | 5154c08d1659da8b3070ce628c9eca994c1c911f /net/bridge/br_mst.c | |
| parent | 8dca36978aa80bab9d4da130c211db75c9e00048 (diff) | |
net: bridge: fix MST static key usage
As Ido pointed out, the static key usage in MST is buggy and should use
inc/dec instead of enable/disable because we can have multiple bridges
with MST enabled which means a single bridge can disable MST for all.
Use static_branch_inc/dec to avoid that. When destroying a bridge decrement
the key if MST was enabled.
Fixes: ec7328b59176 ("net: bridge: mst: Multiple Spanning Tree (MST) mode")
Reported-by: Ido Schimmel <idosch@nvidia.com>
Closes: https://lore.kernel.org/netdev/20251104120313.1306566-1-razor@blackwall.org/T/#m6888d87658f94ed1725433940f4f4ebb00b5a68b
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251105111919.1499702-3-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/bridge/br_mst.c')
| -rw-r--r-- | net/bridge/br_mst.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/bridge/br_mst.c b/net/bridge/br_mst.c index 3f24b4ee49c2..43a300ae6bfa 100644 --- a/net/bridge/br_mst.c +++ b/net/bridge/br_mst.c @@ -22,6 +22,12 @@ bool br_mst_enabled(const struct net_device *dev) } EXPORT_SYMBOL_GPL(br_mst_enabled); +void br_mst_uninit(struct net_bridge *br) +{ + if (br_opt_get(br, BROPT_MST_ENABLED)) + static_branch_dec(&br_mst_used); +} + int br_mst_get_info(const struct net_device *dev, u16 msti, unsigned long *vids) { const struct net_bridge_vlan_group *vg; @@ -225,9 +231,9 @@ int br_mst_set_enabled(struct net_bridge *br, bool on, return err; if (on) - static_branch_enable(&br_mst_used); + static_branch_inc(&br_mst_used); else - static_branch_disable(&br_mst_used); + static_branch_dec(&br_mst_used); br_opt_toggle(br, BROPT_MST_ENABLED, on); return 0; |