Fix abort when token is lost in RECOVERY state

A commit token should be rejected when a token is lost in the recovery
state.  This occurs naturally because the ring id increases by 4 for
every new ring.  Prior to this patch, if the token was lost, the old
ring id information was restored, causing a commit token to be accepted
when it should be rejected.  This erronously accepted commit token would
lead to an assertion which is fixed by this patch.

Signed-off-by: Steven Dake <sdake@redhat.com>
Reviewed-by: Angus Salkeld <asalkeld@redhat.com>

diff --git a/exec/totemsrp.c b/exec/totemsrp.c
index c0e21b5edf0addaa90c545b093519ee310b6429f..62794c70d1602a12b10808899be3d2e53594393d 100644 (file)
--- a/exec/totemsrp.c
+++ b/exec/totemsrp.c
@@ -475,8 +475,6 @@ struct totemsrp_instance {
 
        unsigned int set_aru;
 
-       int old_ring_state_saved;
-
        int old_ring_state_aru;
 
        unsigned int old_ring_state_high_seq_received;
@@ -1395,37 +1393,28 @@ static void cancel_merge_detect_timeout (struct totemsrp_instance *instance)
  */
 static void old_ring_state_save (struct totemsrp_instance *instance)
 {
-       if (instance->old_ring_state_saved == 0) {
-               instance->old_ring_state_saved = 1;
-               memcpy (&instance->my_old_ring_id, &instance->my_ring_id,
-                       sizeof (struct memb_ring_id));
-               instance->old_ring_state_aru = instance->my_aru;
-               instance->old_ring_state_high_seq_received = instance->my_high_seq_received;
-               log_printf (instance->totemsrp_log_level_debug,
-                       "Saving state aru %x high seq received %x\n",
-                       instance->my_aru, instance->my_high_seq_received);
-       }
+       memcpy (&instance->my_old_ring_id, &instance->my_ring_id,
+               sizeof (struct memb_ring_id));
+       instance->old_ring_state_aru = instance->my_aru;
+       instance->old_ring_state_high_seq_received = instance->my_high_seq_received;
+       log_printf (instance->totemsrp_log_level_debug,
+               "Saving state aru %x high seq received %x\n",
+               instance->my_aru, instance->my_high_seq_received);
 }
 
-static void ring_state_restore (struct totemsrp_instance *instance)
+static void old_ring_state_restore (struct totemsrp_instance *instance)
 {
-       if (instance->old_ring_state_saved) {
-               memcpy (&instance->my_ring_id, &instance->my_old_ring_id,
-                       sizeof (struct memb_ring_id));
-
-               instance->my_aru = instance->old_ring_state_aru;
-               instance->my_high_seq_received = instance->old_ring_state_high_seq_received;
-               log_printf (instance->totemsrp_log_level_debug,
-                       "Restoring instance->my_aru %x my high seq received %x\n",
-                       instance->my_aru, instance->my_high_seq_received);
-       }
+       instance->my_aru = instance->old_ring_state_aru;
+       instance->my_high_seq_received = instance->old_ring_state_high_seq_received;
+       log_printf (instance->totemsrp_log_level_debug,
+               "Restoring instance->my_aru %x my high seq received %x\n",
+               instance->my_aru, instance->my_high_seq_received);
 }
 
 static void old_ring_state_reset (struct totemsrp_instance *instance)
 {
        log_printf (instance->totemsrp_log_level_debug,
                "Resetting old ring state\n");
-       instance->old_ring_state_saved = 0;
 }
 
 static void reset_pause_timeout (struct totemsrp_instance *instance)
@@ -1527,6 +1516,13 @@ static void timer_function_pause_timeout (void *data)
        reset_pause_timeout (instance);
 }
 
+static void memb_recovery_state_token_loss (struct totemsrp_instance *instance)
+{
+       old_ring_state_restore (instance);
+       memb_state_gather_enter (instance, 5);
+       instance->stats.recovery_token_lost++;
+}
+
 static void timer_function_orf_token_timeout (void *data)
 {
        struct totemsrp_instance *instance = data;
@@ -1560,9 +1556,7 @@ static void timer_function_orf_token_timeout (void *data)
                case MEMB_STATE_RECOVERY:
                        log_printf (instance->totemsrp_log_level_debug,
                                "The token was lost in the RECOVERY state.\n");
-                       ring_state_restore (instance);
-                       memb_state_gather_enter (instance, 5);
-                       instance->stats.recovery_token_lost++;
+                       memb_recovery_state_token_loss (instance);
                        break;
        }
 }
@@ -2364,16 +2358,6 @@ static int orf_token_mcast (
                        break;
                }
                message_item = (struct message_item *)cs_queue_item_get (mcast_queue);
-               /* preincrement required by algo */
-               if (instance->old_ring_state_saved &&
-                       (instance->memb_state == MEMB_STATE_GATHER ||
-                       instance->memb_state == MEMB_STATE_COMMIT)) {
-
-                       log_printf (instance->totemsrp_log_level_debug,
-                               "not multicasting at seqno is %d\n",
-                       token->seq);
-                       return (0);
-               }
 
                message_item->mcast->seq = ++token->seq;
                message_item->mcast->this_seqno = instance->global_seqno++;
@@ -4222,9 +4206,8 @@ static int message_handler_memb_join (
 
                                memb_join->ring_seq >= instance->my_ring_id.seq) {
 
-                               ring_state_restore (instance);
-
                                memb_join_process (instance, memb_join);
+                               memb_recovery_state_token_loss (instance);
                                memb_state_gather_enter (instance, 14);
                        }
                        break;