This is a note to let you know that I've just added the patch titled
net: bridge: multicast: fix PIM hello router port marking race
to the 5.12-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-multicast-fix-pim-hello-router-port-marking-race.patch
and it can be found in the queue-5.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 04bef83a3358946bfc98a5ecebd1b0003d83d882 Mon Sep 17 00:00:00 2001
From: Nikolay Aleksandrov <nikolay@xxxxxxxxxx>
Date: Sun, 11 Jul 2021 12:56:28 +0300
Subject: net: bridge: multicast: fix PIM hello router port marking race
From: Nikolay Aleksandrov <nikolay@xxxxxxxxxx>
commit 04bef83a3358946bfc98a5ecebd1b0003d83d882 upstream.
When a PIM hello packet is received on a bridge port with multicast
snooping enabled, we mark it as a router port automatically, that
includes adding that port the router port list. The multicast lock
protects that list, but it is not acquired in the PIM message case
leading to a race condition, we need to take it to fix the race.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 91b02d3d133b ("bridge: mcast: add router port on PIM hello message")
Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bridge/br_multicast.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -3087,7 +3087,9 @@ static void br_multicast_pim(struct net_
pim_hdr_type(pimhdr) != PIM_TYPE_HELLO)
return;
+ spin_lock(&br->multicast_lock);
br_multicast_mark_router(br, port);
+ spin_unlock(&br->multicast_lock);
}
static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
Patches currently in stable-queue which might be from nikolay@xxxxxxxxxx are
queue-5.12/net-bridge-multicast-fix-mrd-advertisement-router-port-marking-race.patch
queue-5.12/net-bridge-multicast-fix-pim-hello-router-port-marking-race.patch
