fix bitArray nil bugs

common/bit_array.go

@@ -21,14 +21,19 @@ func NewBitArray(bits uint) *BitArray {
 }
 
 func (bA *BitArray) Size() uint {
+	if bA == nil {
+		return 0
+	}
 	return bA.Bits
 }
 
 // NOTE: behavior is undefined if i >= bA.Bits
 func (bA *BitArray) GetIndex(i uint) bool {
+	if bA == nil {
+		return false
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	return bA.getIndex(i)
 }
 
@@ -41,9 +46,11 @@ func (bA *BitArray) getIndex(i uint) bool {
 
 // NOTE: behavior is undefined if i >= bA.Bits
 func (bA *BitArray) SetIndex(i uint, v bool) bool {
+	if bA == nil {
+		return false
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	return bA.setIndex(i, v)
 }
 
@@ -60,6 +67,9 @@ func (bA *BitArray) setIndex(i uint, v bool) bool {
 }
 
 func (bA *BitArray) Copy() *BitArray {
+	if bA == nil {
+		return nil
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
 	return bA.copy()
@@ -85,9 +95,11 @@ func (bA *BitArray) copyBits(bits uint) *BitArray {
 
 // Returns a BitArray of larger bits size.
 func (bA *BitArray) Or(o *BitArray) *BitArray {
+	if bA == nil {
+		o.Copy()
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	c := bA.copyBits(MaxUint(bA.Bits, o.Bits))
 	for i := 0; i < len(c.Elems); i++ {
 		c.Elems[i] |= o.Elems[i]
@@ -97,9 +109,11 @@ func (bA *BitArray) Or(o *BitArray) *BitArray {
 
 // Returns a BitArray of smaller bit size.
 func (bA *BitArray) And(o *BitArray) *BitArray {
+	if bA == nil {
+		return nil
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	return bA.and(o)
 }
 
@@ -112,9 +126,11 @@ func (bA *BitArray) and(o *BitArray) *BitArray {
 }
 
 func (bA *BitArray) Not() *BitArray {
+	if bA == nil {
+		return nil // Degenerate
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	c := bA.copy()
 	for i := 0; i < len(c.Elems); i++ {
 		c.Elems[i] = ^c.Elems[i]
@@ -123,9 +139,11 @@ func (bA *BitArray) Not() *BitArray {
 }
 
 func (bA *BitArray) Sub(o *BitArray) *BitArray {
+	if bA == nil {
+		return nil
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	if bA.Bits > o.Bits {
 		c := bA.copy()
 		for i := 0; i < len(o.Elems)-1; i++ {
@@ -139,11 +157,14 @@ func (bA *BitArray) Sub(o *BitArray) *BitArray {
 		}
 		return c
 	} else {
-		return bA.and(o.Not())
+		return bA.and(o.Not()) // Note degenerate case where o == nil
 	}
 }
 
 func (bA *BitArray) IsFull() bool {
+	if bA == nil {
+		return true
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
 
@@ -165,6 +186,9 @@ func (bA *BitArray) IsFull() bool {
 }
 
 func (bA *BitArray) PickRandom() (uint, bool) {
+	if bA == nil {
+		return 0, false
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
 
@@ -210,14 +234,16 @@ func (bA *BitArray) String() string {
 	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-
 	return bA.stringIndented("")
 }
 
 func (bA *BitArray) StringIndented(indent string) string {
+	if bA == nil {
+		return "nil-BitArray"
+	}
 	bA.mtx.Lock()
 	defer bA.mtx.Unlock()
-	return bA.StringIndented(indent)
+	return bA.stringIndented(indent)
 }
 
 func (bA *BitArray) stringIndented(indent string) string {

consensus/reactor.go

@@ -433,7 +433,6 @@ OUTER_LOOP:
 			return
 		}
 		rs := conR.conS.GetRoundState()
-		ps.EnsureVoteBitArrays(rs.Height, rs.Validators.Size())
 		prs := ps.GetRoundState()
 
 		switch sleeping {
@@ -443,7 +442,14 @@ OUTER_LOOP:
 			sleeping = 0
 		}
 
-		trySendVote := func(voteSet *VoteSet, peerVoteSet *BitArray) (sent bool) {
+		// Returns true when useful work was done.
+		trySendVote := func(height uint, voteSet *VoteSet, peerVoteSet *BitArray) (sent bool) {
+			if voteSet == nil {
+				return false
+			} else if peerVoteSet == nil {
+				ps.EnsureVoteBitArrays(height, voteSet.Size())
+				return true
+			}
 			// TODO: give priority to our vote.
 			if index, ok := voteSet.BitArray().Sub(peerVoteSet.Copy()).PickRandom(); ok {
 				vote := voteSet.GetByIndex(index)
@@ -456,7 +462,14 @@ OUTER_LOOP:
 			return false
 		}
 
+		// Returns true when useful work was done.
 		trySendCommitFromValidation := func(blockMeta *types.BlockMeta, validation *types.Validation, peerVoteSet *BitArray) (sent bool) {
+			if validation == nil {
+				return false
+			} else if peerVoteSet == nil {
+				ps.EnsureVoteBitArrays(blockMeta.Header.Height, uint(len(validation.Commits)))
+				return true
+			}
 			if index, ok := validation.BitArray().Sub(prs.Commits.Copy()).PickRandom(); ok {
 				commit := validation.Commits[index]
 				log.Debug("Picked commit to send", "index", index, "commit", commit)
@@ -482,31 +495,27 @@ OUTER_LOOP:
 
 			// If there are lastcommits to send...
 			if prs.Round == 0 && prs.Step == RoundStepNewHeight {
-				if prs.LastCommits != nil && rs.LastCommits != nil {
-					if prs.LastCommits.Size() == rs.LastCommits.Size() {
-						if trySendVote(rs.LastCommits, prs.LastCommits) {
-							continue OUTER_LOOP
-						}
-					}
+				if trySendVote(rs.Height-1, rs.LastCommits, prs.LastCommits) {
+					continue OUTER_LOOP
 				}
 			}
 
 			// If there are prevotes to send...
 			if rs.Round == prs.Round && prs.Step <= RoundStepPrevote {
-				if trySendVote(rs.Prevotes, prs.Prevotes) {
+				if trySendVote(rs.Height, rs.Prevotes, prs.Prevotes) {
 					continue OUTER_LOOP
 				}
 			}
 
 			// If there are precommits to send...
 			if rs.Round == prs.Round && prs.Step <= RoundStepPrecommit {
-				if trySendVote(rs.Precommits, prs.Precommits) {
+				if trySendVote(rs.Height, rs.Precommits, prs.Precommits) {
 					continue OUTER_LOOP
 				}
 			}
 
 			// If there are any commits to send...
-			if trySendVote(rs.Commits, prs.Commits) {
+			if trySendVote(rs.Height, rs.Commits, prs.Commits) {
 				continue OUTER_LOOP
 			}
 		}
@@ -517,7 +526,7 @@ OUTER_LOOP:
 			// If peer is lagging by height 1, match our LastCommits or SeenValidation to peer's Commits.
 			if rs.Height == prs.Height+1 && rs.LastCommits.Size() > 0 {
 				// If there are lastcommits to send...
-				if trySendVote(rs.LastCommits, prs.Commits) {
+				if trySendVote(prs.Height, rs.LastCommits, prs.Commits) {
 					continue OUTER_LOOP
 				} else {
 					ps.SetHasAllCatchupCommits(prs.Height)
@@ -665,18 +674,20 @@ func (ps *PeerState) EnsureVoteBitArrays(height uint, numValidators uint) {
 	ps.mtx.Lock()
 	defer ps.mtx.Unlock()
 
-	if ps.Height != height {
-		return
-	}
-
-	if ps.Prevotes == nil {
-		ps.Prevotes = NewBitArray(numValidators)
-	}
-	if ps.Precommits == nil {
-		ps.Precommits = NewBitArray(numValidators)
-	}
-	if ps.Commits == nil {
-		ps.Commits = NewBitArray(numValidators)
+	if ps.Height == height {
+		if ps.Prevotes == nil {
+			ps.Prevotes = NewBitArray(numValidators)
+		}
+		if ps.Precommits == nil {
+			ps.Precommits = NewBitArray(numValidators)
+		}
+		if ps.Commits == nil {
+			ps.Commits = NewBitArray(numValidators)
+		}
+	} else if ps.Height == height+1 {
+		if ps.LastCommits == nil {
+			ps.LastCommits = NewBitArray(numValidators)
+		}
 	}
 }