conntrack: Init hash basis first at creation.

The 'hash_basis' field is used sometimes during sub-systems init routine. It will be 0 by default before randomization. Sub-systems would then init some nodes with incorrect hash values. The timeout policies module is affected, making the default policy being referenced using an incorrect hash value. Fixes: 2078901 ("userspace: Add conntrack timeout policy support.") Signed-off-by: Gaetan Rivet <[email protected]> Reviewed-by: Eli Britstein <[email protected]> Acked-by: William Tu <[email protected]> Signed-off-by: Ilya Maximets <[email protected]>
dqadri · Jul 9, 2021 · b889d5d · b889d5d
1 parent b0d289b
commit b889d5d
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/lib/conntrack.c b/lib/conntrack.c
@@ -293,6 +293,11 @@ conntrack_init(void)
     static struct ovsthread_once setup_l4_once = OVSTHREAD_ONCE_INITIALIZER;
     struct conntrack *ct = xzalloc(sizeof *ct);
 
+    /* This value can be used during init (e.g. timeout_policy_init()),
+     * set it first to ensure it is available.
+     */
+    ct->hash_basis = random_uint32();
+
     ovs_rwlock_init(&ct->resources_lock);
     ovs_rwlock_wrlock(&ct->resources_lock);
     hmap_init(&ct->alg_expectations);
@@ -310,7 +315,6 @@ conntrack_init(void)
     timeout_policy_init(ct);
     ovs_mutex_unlock(&ct->ct_lock);
 
-    ct->hash_basis = random_uint32();
     atomic_count_init(&ct->n_conn, 0);
     atomic_init(&ct->n_conn_limit, DEFAULT_N_CONN_LIMIT);
     atomic_init(&ct->tcp_seq_chk, true);