BUG/MEDIUM: threads/stick-tables: close a race condition on stktable_trash_expired()
The spin_unlock() was called just before setting the expiry to
TICK_ETERNITY, so if another thread has the time to perform its
update and set a timeout, this would would clear it.
diff --git a/src/stick_table.c b/src/stick_table.c
index 0e84102..4810c7f 100644
--- a/src/stick_table.c
+++ b/src/stick_table.c
@@ -536,8 +536,7 @@
if (likely(tick_is_lt(now_ms, eb->key))) {
/* timer not expired yet, revisit it later */
t->exp_next = eb->key;
- SPIN_UNLOCK(STK_TABLE_LOCK, &t->lock);
- return t->exp_next;
+ goto out_unlock;
}
/* timer looks expired, detach it from the queue */
@@ -567,10 +566,11 @@
eb32_delete(&ts->upd);
__stksess_free(t, ts);
}
- SPIN_UNLOCK(STK_TABLE_LOCK, &t->lock);
/* We have found no task to expire in any tree */
t->exp_next = TICK_ETERNITY;
+out_unlock:
+ SPIN_UNLOCK(STK_TABLE_LOCK, &t->lock);
return t->exp_next;
}