This is a note to let you know that I've just added the patch titled
net: bridge: mst: fix suspicious rcu usage in br_mst_set_state
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-bridge-mst-fix-suspicious-rcu-usage-in-br_mst_se.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d6ad38f77cb948f08b869df249a4eef17f01aefa
Author: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>
Date: Sun Jun 9 13:36:54 2024 +0300
net: bridge: mst: fix suspicious rcu usage in br_mst_set_state
[ Upstream commit 546ceb1dfdac866648ec959cbc71d9525bd73462 ]
I converted br_mst_set_state to RCU to avoid a vlan use-after-free
but forgot to change the vlan group dereference helper. Switch to vlan
group RCU deref helper to fix the suspicious rcu usage warning.
Fixes: 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free")
Reported-by: syzbot+9bbe2de1bc9d470eb5fe@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe
Signed-off-by: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240609103654.914987-3-razor@xxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/bridge/br_mst.c b/net/bridge/br_mst.c
index 1de72816b0fb2..1820f09ff59ce 100644
--- a/net/bridge/br_mst.c
+++ b/net/bridge/br_mst.c
@@ -102,7 +102,7 @@ int br_mst_set_state(struct net_bridge_port *p, u16 msti, u8 state,
int err = 0;
rcu_read_lock();
- vg = nbp_vlan_group(p);
+ vg = nbp_vlan_group_rcu(p);
if (!vg)
goto out;
