net: bridge: multicast: fix PIM hello router port marking race

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@vger.kernel.org
Fixes: 91b02d3d13 ("bridge: mcast: add router port on PIM hello message")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nikolay Aleksandrov 2021-07-11 12:56:28 +03:00 committed by Greg Kroah-Hartman
parent b3aea76efe
commit 664cc645bd

View File

@ -2998,7 +2998,9 @@ static void br_multicast_pim(struct net_bridge *br,
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,