From 18eebcca8234bcfd1176721e6adc5e63af675291 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Thu, 25 Oct 2018 14:49:32 +0200 Subject: global: do not allow compiler to reorder is_valid or is_dead Suggested-by: Jann Horn Signed-off-by: Jason A. Donenfeld --- src/send.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'src/send.c') diff --git a/src/send.c b/src/send.c index b7f8283..1e97aa1 100644 --- a/src/send.c +++ b/src/send.c @@ -65,7 +65,8 @@ void wg_packet_send_queued_handshake_initiation(struct wg_peer *peer, * necessary: */ if (!wg_birthdate_has_expired(atomic64_read(&peer->last_sent_handshake), - REKEY_TIMEOUT) || unlikely(peer->is_dead)) + REKEY_TIMEOUT) || + unlikely(READ_ONCE(peer->is_dead))) goto out; wg_peer_get(peer); @@ -128,7 +129,7 @@ static void keep_key_fresh(struct wg_peer *peer) rcu_read_lock_bh(); keypair = rcu_dereference_bh(peer->keypairs.current_keypair); - if (likely(keypair && keypair->sending.is_valid) && + if (likely(keypair && READ_ONCE(keypair->sending.is_valid)) && (unlikely(atomic64_read(&keypair->sending.counter.counter) > REKEY_AFTER_MESSAGES) || (keypair->i_am_the_initiator && @@ -327,7 +328,7 @@ static void wg_packet_create_data(struct sk_buff *first) int ret = -EINVAL; rcu_read_lock_bh(); - if (unlikely(peer->is_dead)) + if (unlikely(READ_ONCE(peer->is_dead))) goto err; ret = wg_queue_enqueue_per_device_and_peer(&wg->encrypt_queue, @@ -369,7 +370,7 @@ void wg_packet_send_staged_packets(struct wg_peer *peer) if (unlikely(!keypair)) goto out_nokey; key = &keypair->sending; - if (unlikely(!key->is_valid)) + if (unlikely(!READ_ONCE(key->is_valid))) goto out_nokey; if (unlikely(wg_birthdate_has_expired(key->birthdate, REJECT_AFTER_TIME))) @@ -398,7 +399,7 @@ void wg_packet_send_staged_packets(struct wg_peer *peer) return; out_invalid: - key->is_valid = false; + WRITE_ONCE(key->is_valid, false); out_nokey: wg_noise_keypair_put(keypair, false); -- cgit v1.2.3-59-g8ed1b