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| author | Nikolay Aleksandrov <razor@blackwall.org> | 2025-11-05 13:19:19 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-11-13 15:34:39 -0500 |
| commit | 29d4429a993f10c5a9f55c265283c3fd4d0832f5 (patch) | |
| tree | bf3433352db7bcc9933eaa553480caf14df36149 | |
| parent | bf3843183bc3158e5821b46f330c438ae9bd6ddb (diff) | |
| download | linux-29d4429a993f10c5a9f55c265283c3fd4d0832f5.tar.gz linux-29d4429a993f10c5a9f55c265283c3fd4d0832f5.tar.bz2 linux-29d4429a993f10c5a9f55c265283c3fd4d0832f5.zip | |
net: bridge: fix MST static key usage
[ Upstream commit ee87c63f9b2a418f698d79c2991347e31a7d2c27 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/bridge/br_if.c | 1 | ||||
| -rw-r--r-- | net/bridge/br_mst.c | 10 | ||||
| -rw-r--r-- | net/bridge/br_private.h | 5 |
3 files changed, 14 insertions, 2 deletions
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c index 2450690f98cf..6ffc81eedf07 100644 --- a/net/bridge/br_if.c +++ b/net/bridge/br_if.c @@ -386,6 +386,7 @@ void br_dev_delete(struct net_device *dev, struct list_head *head) del_nbp(p); } + br_mst_uninit(br); br_recalculate_neigh_suppress_enabled(br); br_fdb_delete_by_port(br, NULL, 0, 1); 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; diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 40dcffc2132e..741b0b8c4bab 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -1923,6 +1923,7 @@ int br_mst_fill_info(struct sk_buff *skb, const struct net_bridge_vlan_group *vg); int br_mst_process(struct net_bridge_port *p, const struct nlattr *mst_attr, struct netlink_ext_ack *extack); +void br_mst_uninit(struct net_bridge *br); #else static inline bool br_mst_is_enabled(const struct net_bridge_port *p) { @@ -1958,6 +1959,10 @@ static inline int br_mst_process(struct net_bridge_port *p, { return -EOPNOTSUPP; } + +static inline void br_mst_uninit(struct net_bridge *br) +{ +} #endif struct nf_br_ops { |