target/linux/generic/backport-5.4/080-wireguard-0087-wireguard-receive-reset-last_under_load-to-zero.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: "Jason A. Donenfeld" <Jason@zx2c4.com>
   3 Date: Fri, 14 Feb 2020 23:57:21 +0100
   4 Subject: [PATCH] wireguard: receive: reset last_under_load to zero
   5
   6 commit 2a8a4df36462aa85b0db87b7c5ea145ba67e34a8 upstream.
   7
   8 This is a small optimization that prevents more expensive comparisons
   9 from happening when they are no longer necessary, by clearing the
  10 last_under_load variable whenever we wind up in a state where we were
  11 under load but we no longer are.
  12
  13 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
  14 Suggested-by: Matt Dunwoodie <ncon@noconroy.net>
  15 Signed-off-by: David S. Miller <davem@davemloft.net>
  16 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
  17 ---
  18  drivers/net/wireguard/receive.c | 7 +++++--
  19  1 file changed, 5 insertions(+), 2 deletions(-)
  20
  21 --- a/drivers/net/wireguard/receive.c
  22 +++ b/drivers/net/wireguard/receive.c
  23 @@ -118,10 +118,13 @@ static void wg_receive_handshake_packet(
  24
  25         under_load = skb_queue_len(&wg->incoming_handshakes) >=
  26                      MAX_QUEUED_INCOMING_HANDSHAKES / 8;
  27 -       if (under_load)
  28 +       if (under_load) {
  29                 last_under_load = ktime_get_coarse_boottime_ns();
  30 -       else if (last_under_load)
  31 +       } else if (last_under_load) {
  32                 under_load = !wg_birthdate_has_expired(last_under_load, 1);
  33 +               if (!under_load)
  34 +                       last_under_load = 0;
  35 +       }
  36         mac_state = wg_cookie_validate_packet(&wg->cookie_checker, skb,
  37                                               under_load);
  38         if ((under_load && mac_state == VALID_MAC_WITH_COOKIE) ||