send: switch handshake stamp to an atomic

Rather than abusing the handshake lock, we're much better off just using
a boring atomic64 for this. It's simpler and performs better.

Also, while we're at it, we set the handshake stamp both before and
after the calculations, in case the calculations block for a really long
time waiting for the RNG to initialize. Otherwise it's possible that
when the RNG finally initializes, two handshakes are sent back to back,
which isn't sensible.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/peer.c b/src/peer.c
index 97a472a..b9703d5 100644
--- a/src/peer.c
+++ b/src/peer.c
@@ -50,7 +50,7 @@ struct wireguard_peer *peer_create(struct wireguard_device *wg, const u8 public_
 	rwlock_init(&peer->endpoint_lock);
 	kref_init(&peer->refcount);
 	skb_queue_head_init(&peer->staged_packet_queue);
-	peer->last_sent_handshake = ktime_get_boot_fast_ns() - (u64)(REKEY_TIMEOUT + 1) * NSEC_PER_SEC;
+	atomic64_set(&peer->last_sent_handshake, ktime_get_boot_fast_ns() - (u64)(REKEY_TIMEOUT + 1) * NSEC_PER_SEC);
 	set_bit(NAPI_STATE_NO_BUSY_POLL, &peer->napi.state);
 	netif_napi_add(wg->dev, &peer->napi, packet_rx_poll, NAPI_POLL_WEIGHT);
 	napi_enable(&peer->napi);