ike-sa: Avoid possible integer underflow when scheduling reauth after rekeying

If the reauthentication is scheduled while rekeying, the difference
might be negative, however, schedule_job() takes an unsigned int,
so the reauth would get scheduled very far in the future.

diff --git a/src/libcharon/sa/ike_sa.c b/src/libcharon/sa/ike_sa.c
index 99c1116ca43c6ff2bbca3a4dd665d9c278975bf6..0f6f433cf19989f120f871033b48d24ab5966ed1 100644 (file)
--- a/src/libcharon/sa/ike_sa.c
+++ b/src/libcharon/sa/ike_sa.c
@@ -2982,7 +2982,7 @@ METHOD(ike_sa_t, inherit_post, void,
                time_t reauth, delete, now = time_monotonic(NULL);
 
                this->stats[STAT_REAUTH] = other->stats[STAT_REAUTH];
-               reauth = this->stats[STAT_REAUTH] - now;
+               reauth = max(0, this->stats[STAT_REAUTH] - now);
                delete = reauth + this->peer_cfg->get_over_time(this->peer_cfg);
                this->stats[STAT_DELETE] = this->stats[STAT_REAUTH] + delete;
                DBG1(DBG_IKE, "rescheduling reauthentication in %ds after rekeying, "