net: make sure napi_list is safe for RCU traversal

netpoll needs to traverse dev->napi_list under RCU, make sure it uses the right iterator and that removal from this list is handled safely. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
mariux64 · Sep 10, 2020 · 5251ef8 · 5251ef8
1 parent 4d092dd
commit 5251ef8
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Showing 2 changed files with 2 additions and 2 deletions.
diff --git a/net/core/dev.c b/net/core/dev.c
@@ -6656,7 +6656,7 @@ void __netif_napi_del(struct napi_struct *napi)
 		return;
 
 	napi_hash_del(napi);
-	list_del_init(&napi->dev_list);
+	list_del_rcu(&napi->dev_list);
 	napi_free_frags(napi);
 
 	flush_gro_hash(napi);

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
@@ -297,7 +297,7 @@ static int netpoll_owner_active(struct net_device *dev)
 {
 	struct napi_struct *napi;
 
-	list_for_each_entry(napi, &dev->napi_list, dev_list) {
+	list_for_each_entry_rcu(napi, &dev->napi_list, dev_list) {
 		if (napi->poll_owner == smp_processor_id())
 			return 1;
 	}