From 0ad57c99e857f4c7354c3629d4168061fba4a22a Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Wed, 20 Jan 2021 16:51:52 +0200 Subject: [PATCH] net: bridge: multicast: __grp_src_block_incl can modify pg Prepare __grp_src_block_incl() for being able to cause a notification due to changes. Currently it cannot happen, but EHT would change that since we'll be deleting sources immediately. Make sure that if the pg is deleted we don't return true as that would cause the caller to access freed pg. This patch shouldn't cause any functional change. Signed-off-by: Nikolay Aleksandrov Signed-off-by: Jakub Kicinski --- net/bridge/br_multicast.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 861545094d67..79569a398669 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -2142,11 +2142,12 @@ static bool br_multicast_toex(struct net_bridge_port_group *pg, void *h_addr, /* State Msg type New state Actions * INCLUDE (A) BLOCK (B) INCLUDE (A) Send Q(G,A*B) */ -static void __grp_src_block_incl(struct net_bridge_port_group *pg, void *h_addr, +static bool __grp_src_block_incl(struct net_bridge_port_group *pg, void *h_addr, void *srcs, u32 nsrcs, size_t addr_size) { struct net_bridge_group_src *ent; u32 src_idx, to_send = 0; + bool changed = false; struct br_ip src_ip; hlist_for_each_entry(ent, &pg->src_list, node) @@ -2167,8 +2168,15 @@ static void __grp_src_block_incl(struct net_bridge_port_group *pg, void *h_addr, if (to_send) __grp_src_query_marked_and_rexmit(pg); - if (pg->filter_mode == MCAST_INCLUDE && hlist_empty(&pg->src_list)) + if (pg->filter_mode == MCAST_INCLUDE && hlist_empty(&pg->src_list)) { br_multicast_find_del_pg(pg->key.port->br, pg); + /* a notification has already been sent and we shouldn't access + * pg after the delete thus we have to return false + */ + changed = false; + } + + return changed; } /* State Msg type New state Actions @@ -2218,7 +2226,7 @@ static bool br_multicast_block(struct net_bridge_port_group *pg, void *h_addr, switch (pg->filter_mode) { case MCAST_INCLUDE: - __grp_src_block_incl(pg, h_addr, srcs, nsrcs, addr_size); + changed = __grp_src_block_incl(pg, h_addr, srcs, nsrcs, addr_size); break; case MCAST_EXCLUDE: changed = __grp_src_block_excl(pg, h_addr, srcs, nsrcs, addr_size);