core: optimize handling for bad block (#574)

* core: optimize handling for bad block

* fix test

1 files changed, 23 insertions, 8 deletions

diff --git a/core/agreement.go b/core/agreement.go
index 7830af0..2215394 100644
--- a/core/agreement.go
+++ b/core/agreement.go
@@ -640,19 +640,34 @@ func (a *agreement) confirmedNoLock() bool {
 
 // processBlock is the entry point for processing Block.
 func (a *agreement) processBlock(block *types.Block) error {
+	checkSkip := func() bool {
+		aID := a.agreementID()
+		if block.Position != aID {
+			// Agreement module has stopped.
+			if !isStop(aID) {
+				if aID.Newer(block.Position) {
+					return true
+				}
+			}
+		}
+		return false
+	}
+	if checkSkip() {
+		return nil
+	}
+	if err := utils.VerifyBlockSignature(block); err != nil {
+		return err
+	}
+
 	a.lock.Lock()
 	defer a.lock.Unlock()
 	a.data.blocksLock.Lock()
 	defer a.data.blocksLock.Unlock()
-
 	aID := a.agreementID()
-	if block.Position != aID {
-		// Agreement module has stopped.
-		if !isStop(aID) {
-			if aID.Newer(block.Position) {
-				return nil
-			}
-		}
+	// a.agreementID might change during lock, so we need to checkSkip again.
+	if checkSkip() {
+		return nil
+	} else if aID != block.Position {
 		a.pendingBlock = append(a.pendingBlock, pendingBlock{
 			block:        block,
 			receivedTime: time.Now().UTC(),