From: Cong Wang <xiyou.wangcong@xxxxxxxxx> [ Upstream commit 9708d2b5b7c648e8e0a40d11e8cea12f6277f33c ] llc_sap_close() is called by llc_sap_put() which could be called in BH context in llc_rcv(). We can't block in BH. There is no reason to block it here, kfree_rcu() should be sufficient. Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- include/net/llc.h | 1 + net/llc/llc_core.c | 4 +--- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/include/net/llc.h b/include/net/llc.h index 890a87318014d..df282d9b40170 100644 --- a/include/net/llc.h +++ b/include/net/llc.h @@ -66,6 +66,7 @@ struct llc_sap { int sk_count; struct hlist_nulls_head sk_laddr_hash[LLC_SK_LADDR_HASH_ENTRIES]; struct hlist_head sk_dev_hash[LLC_SK_DEV_HASH_ENTRIES]; + struct rcu_head rcu; }; static inline diff --git a/net/llc/llc_core.c b/net/llc/llc_core.c index 260b3dc1b4a2a..64d4bef04e730 100644 --- a/net/llc/llc_core.c +++ b/net/llc/llc_core.c @@ -127,9 +127,7 @@ void llc_sap_close(struct llc_sap *sap) list_del_rcu(&sap->node); spin_unlock_bh(&llc_sap_list_lock); - synchronize_rcu(); - - kfree(sap); + kfree_rcu(sap, rcu); } static struct packet_type llc_packet_type __read_mostly = { -- 2.20.1