Commit 90638373 authored Nov 11, 2022 by Chuang Wang Committed by Greg Kroah-Hartman Nov 25, 2022

net: macvlan: Use built-in RCU list checking



[ Upstream commit 5df1341ea822292275c56744aab9c536d75c33be ]

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to hlist_for_each_entry_rcu() to silence false
lockdep warning when CONFIG_PROVE_RCU_LIST is enabled.

Execute as follow:

 ip link add link eth0 type macvlan mode source macaddr add <MAC-ADDR>

The rtnl_lock is held when macvlan_hash_lookup_source() or
macvlan_fill_info_macaddr() are called in the non-RCU read side section.
So, pass lockdep_rtnl_is_held() to silence false lockdep warning.

Fixes: 79cf79ab ("macvlan: add source mode")
Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 83672c1b

drivers/net/macvlan.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -138,7 +138,7 @@ static struct macvlan_source_entry *macvlan_hash_lookup_source(
		u32 idx = macvlan_eth_hash(addr);
		struct hlist_head *h = &vlan->port->vlan_source_hash[idx];

		hlist_for_each_entry_rcu(entry, h, hlist) {
		hlist_for_each_entry_rcu(entry, h, hlist, lockdep_rtnl_is_held()) {
		if (ether_addr_equal_64bits(entry->addr, addr) &&
		entry->vlan == vlan)
		return entry;
		@@ -1604,7 +1604,7 @@ static int macvlan_fill_info_macaddr(struct sk_buff *skb,
		struct hlist_head *h = &vlan->port->vlan_source_hash[i];
		struct macvlan_source_entry *entry;

		hlist_for_each_entry_rcu(entry, h, hlist) {
		hlist_for_each_entry_rcu(entry, h, hlist, lockdep_rtnl_is_held()) {
		if (entry->vlan != vlan)
		continue;
		if (nla_put(skb, IFLA_MACVLAN_MACADDR, ETH_ALEN, entry->addr))