| From 04bef83a3358946bfc98a5ecebd1b0003d83d882 Mon Sep 17 00:00:00 2001 |
| From: Nikolay Aleksandrov <nikolay@nvidia.com> |
| Date: Sun, 11 Jul 2021 12:56:28 +0300 |
| Subject: net: bridge: multicast: fix PIM hello router port marking race |
| |
| From: Nikolay Aleksandrov <nikolay@nvidia.com> |
| |
| 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: 91b02d3d133b ("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> |
| --- |
| 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, |