abci: localClient improvements & bugfixes & pubsub Unsubscribe issues (#2748)

* use READ lock/unlock in ConsensusState#GetLastHeight

Refs #2721

* do not use defers when there's no need

* fix peer formatting (output its address instead of the pointer)

```
[54310]: E[11-02|11:59:39.851] Connection failed @ sendRoutine              module=p2p peer=0xb78f00 conn=MConn{74.207.236.148:26656} err="pong timeout"
```

https://github.com/tendermint/tendermint/issues/2721#issuecomment-435326581

* panic if peer has no state

https://github.com/tendermint/tendermint/issues/2721#issuecomment-435347165

It's confusing that sometimes we check if peer has a state, but most of
the times we expect it to be there

1. add79700b5/mempool/reactor.go (L138)
2. add79700b5/rpc/core/consensus.go (L196) (edited)

I will change everything to always assume peer has a state and panic
otherwise

that should help identify issues earlier

* abci/localclient: extend lock on app callback

App callback should be protected by lock as well (note this was already
done for InitChainAsync, why not for others???). Otherwise, when we
execute the block, tx might come in and call the callback in the same
time we're updating it in execBlockOnProxyApp => DATA RACE

Fixes #2721

Consensus state is locked

```
goroutine 113333 [semacquire, 309 minutes]:
sync.runtime_SemacquireMutex(0xc00180009c, 0xc0000c7e00)
        /usr/local/go/src/runtime/sema.go:71 +0x3d
sync.(*RWMutex).RLock(0xc001800090)
        /usr/local/go/src/sync/rwmutex.go:50 +0x4e
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).GetRoundState(0xc001800000, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:218 +0x46
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusReactor).queryMaj23Routine(0xc0017def80, 0x11104a0, 0xc0072488f0, 0xc007248
9c0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/reactor.go:735 +0x16d
created by github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusReactor).AddPeer
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/reactor.go:172 +0x236
```

because localClient is locked

```
goroutine 1899 [semacquire, 309 minutes]:
sync.runtime_SemacquireMutex(0xc00003363c, 0xc0000cb500)
        /usr/local/go/src/runtime/sema.go:71 +0x3d
sync.(*Mutex).Lock(0xc000033638)
        /usr/local/go/src/sync/mutex.go:134 +0xff
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/abci/client.(*localClient).SetResponseCallback(0xc0001fb560, 0xc007868540)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/abci/client/local_client.go:32 +0x33
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/proxy.(*appConnConsensus).SetResponseCallback(0xc00002f750, 0xc007868540)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/proxy/app_conn.go:57 +0x40
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/state.execBlockOnProxyApp(0x1104e20, 0xc002ca0ba0, 0x11092a0, 0xc00002f750, 0xc0001fe960, 0xc000bfc660, 0x110cfe0, 0xc000090330, 0xc9d12, 0xc000d9d5a0, ...)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/state/execution.go:230 +0x1fd
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/state.(*BlockExecutor).ApplyBlock(0xc002c2a230, 0x7, 0x0, 0xc000eae880, 0x6, 0xc002e52c60, 0x16, 0x1f927, 0xc9d12, 0xc000d9d5a0, ...)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/state/execution.go:96 +0x142
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).finalizeCommit(0xc001800000, 0x1f928)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1339 +0xa3e
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).tryFinalizeCommit(0xc001800000, 0x1f928)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1270 +0x451
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).enterCommit.func1(0xc001800000, 0x0, 0x1f928)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1218 +0x90
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).enterCommit(0xc001800000, 0x1f928, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1247 +0x6b8
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).addVote(0xc001800000, 0xc003d8dea0, 0xc000cf4cc0, 0x28, 0xf1, 0xc003bc7ad0, 0xc003bc7b10)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1659 +0xbad
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).tryAddVote(0xc001800000, 0xc003d8dea0, 0xc000cf4cc0, 0x28, 0xf1, 0xf1, 0xf1)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:1517 +0x59
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).handleMsg(0xc001800000, 0xd98200, 0xc0070dbed0, 0xc000cf4cc0, 0x28)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:660 +0x64b
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).receiveRoutine(0xc001800000, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:617 +0x670
created by github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus.(*ConsensusState).OnStart
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/consensus/state.go:311 +0x132
```

tx comes in and CheckTx is executed right when we execute the block

```
goroutine 111044 [semacquire, 309 minutes]:
sync.runtime_SemacquireMutex(0xc00003363c, 0x0)
        /usr/local/go/src/runtime/sema.go:71 +0x3d
sync.(*Mutex).Lock(0xc000033638)
        /usr/local/go/src/sync/mutex.go:134 +0xff
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/abci/client.(*localClient).CheckTxAsync(0xc0001fb0e0, 0xc002d94500, 0x13f, 0x280, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/abci/client/local_client.go:85 +0x47
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/proxy.(*appConnMempool).CheckTxAsync(0xc00002f720, 0xc002d94500, 0x13f, 0x280, 0x1)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/proxy/app_conn.go:114 +0x51
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/mempool.(*Mempool).CheckTx(0xc002d3a320, 0xc002d94500, 0x13f, 0x280, 0xc0072355f0, 0x0, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/mempool/mempool.go:316 +0x17b
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/core.BroadcastTxSync(0xc002d94500, 0x13f, 0x280, 0x0, 0x0, 0x0)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/core/mempool.go:93 +0xb8
reflect.Value.call(0xd85560, 0x10326c0, 0x13, 0xec7b8b, 0x4, 0xc00663f180, 0x1, 0x1, 0xc00663f180, 0xc00663f188, ...)
        /usr/local/go/src/reflect/value.go:447 +0x449
reflect.Value.Call(0xd85560, 0x10326c0, 0x13, 0xc00663f180, 0x1, 0x1, 0x0, 0x0, 0xc005cc9344)
        /usr/local/go/src/reflect/value.go:308 +0xa4
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server.makeHTTPHandler.func2(0x1102060, 0xc00663f100, 0xc0082d7900)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server/handlers.go:269 +0x188
net/http.HandlerFunc.ServeHTTP(0xc002c81f20, 0x1102060, 0xc00663f100, 0xc0082d7900)
        /usr/local/go/src/net/http/server.go:1964 +0x44
net/http.(*ServeMux).ServeHTTP(0xc002c81b60, 0x1102060, 0xc00663f100, 0xc0082d7900)
        /usr/local/go/src/net/http/server.go:2361 +0x127
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server.maxBytesHandler.ServeHTTP(0x10f8a40, 0xc002c81b60, 0xf4240, 0x1102060, 0xc00663f100, 0xc0082d7900)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server/http_server.go:219 +0xcf
github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server.RecoverAndLogHandler.func1(0x1103220, 0xc00121e620, 0xc0082d7900)
        /root/go/src/github.com/MinterTeam/minter-go-node/vendor/github.com/tendermint/tendermint/rpc/lib/server/http_server.go:192 +0x394
net/http.HandlerFunc.ServeHTTP(0xc002c06ea0, 0x1103220, 0xc00121e620, 0xc0082d7900)
        /usr/local/go/src/net/http/server.go:1964 +0x44
net/http.serverHandler.ServeHTTP(0xc001a1aa90, 0x1103220, 0xc00121e620, 0xc0082d7900)
        /usr/local/go/src/net/http/server.go:2741 +0xab
net/http.(*conn).serve(0xc00785a3c0, 0x11041a0, 0xc000f844c0)
        /usr/local/go/src/net/http/server.go:1847 +0x646
created by net/http.(*Server).Serve
        /usr/local/go/src/net/http/server.go:2851 +0x2f5
```

* consensus: use read lock in Receive#VoteMessage

* use defer to unlock mutex because application might panic

* use defer in every method of the localClient

* add a changelog entry

* drain channels before Unsubscribe(All)

Read 55362ed766/libs/pubsub/pubsub.go (L13)
for the detailed explanation of the issue.

We'll need to fix it someday. Make sure to keep an eye on
https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-033-pubsub.md

* retry instead of panic when peer has no state in reactors other than consensus

in /dump_consensus_state RPC endpoint, skip a peer with no state

* rpc/core/mempool: simplify error messages

* rpc/core/mempool: use time.After instead of timer

also, do not log DeliverTx result (to be consistent with other memthods)

* unlock before calling the callback in reqRes#SetCallback

CHANGELOG_PENDING.md

@@ -26,3 +26,6 @@ Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermi
 
 ### BUG FIXES:
 
+- [abci] unlock mutex in localClient so even when app panics (e.g. during CheckTx), consensus continue working
+- [abci] fix DATA RACE in localClient
+- [rpc] drain channel before calling Unsubscribe(All) in /broadcast_tx_commit

abci/client/client.go

@@ -105,8 +105,8 @@ func (reqRes *ReqRes) SetCallback(cb func(res *types.Response)) {
 		return
 	}
 
-	defer reqRes.mtx.Unlock()
 	reqRes.cb = cb
+	reqRes.mtx.Unlock()
 }
 
 func (reqRes *ReqRes) GetCallback() func(*types.Response) {

abci/client/grpc_client.go

@@ -111,8 +111,8 @@ func (cli *grpcClient) Error() error {
 // NOTE: callback may get internally generated flush responses.
 func (cli *grpcClient) SetResponseCallback(resCb Callback) {
 	cli.mtx.Lock()
-	defer cli.mtx.Unlock()
 	cli.resCb = resCb
+	cli.mtx.Unlock()
 }
 
 //----------------------------------------

abci/client/local_client.go

@@ -9,8 +9,13 @@ import (
 
 var _ Client = (*localClient)(nil)
 
+// NOTE: use defer to unlock mutex because Application might panic (e.g., in
+// case of malicious tx or query). It only makes sense for publicly exposed
+// methods like CheckTx (/broadcast_tx_* RPC endpoint) or Query (/abci_query
+// RPC endpoint), but defers are used everywhere for the sake of consistency.
 type localClient struct {
 	cmn.BaseService
+
 	mtx *sync.Mutex
 	types.Application
 	Callback
@@ -30,8 +35,8 @@ func NewLocalClient(mtx *sync.Mutex, app types.Application) *localClient {
 
 func (app *localClient) SetResponseCallback(cb Callback) {
 	app.mtx.Lock()
-	defer app.mtx.Unlock()
 	app.Callback = cb
+	app.mtx.Unlock()
 }
 
 // TODO: change types.Application to include Error()?
@@ -45,6 +50,9 @@ func (app *localClient) FlushAsync() *ReqRes {
 }
 
 func (app *localClient) EchoAsync(msg string) *ReqRes {
+	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	return app.callback(
 		types.ToRequestEcho(msg),
 		types.ToResponseEcho(msg),
@@ -53,8 +61,9 @@ func (app *localClient) EchoAsync(msg string) *ReqRes {
 
 func (app *localClient) InfoAsync(req types.RequestInfo) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Info(req)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestInfo(req),
 		types.ToResponseInfo(res),
@@ -63,8 +72,9 @@ func (app *localClient) InfoAsync(req types.RequestInfo) *ReqRes {
 
 func (app *localClient) SetOptionAsync(req types.RequestSetOption) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.SetOption(req)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestSetOption(req),
 		types.ToResponseSetOption(res),
@@ -73,8 +83,9 @@ func (app *localClient) SetOptionAsync(req types.RequestSetOption) *ReqRes {
 
 func (app *localClient) DeliverTxAsync(tx []byte) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.DeliverTx(tx)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestDeliverTx(tx),
 		types.ToResponseDeliverTx(res),
@@ -83,8 +94,9 @@ func (app *localClient) DeliverTxAsync(tx []byte) *ReqRes {
 
 func (app *localClient) CheckTxAsync(tx []byte) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.CheckTx(tx)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestCheckTx(tx),
 		types.ToResponseCheckTx(res),
@@ -93,8 +105,9 @@ func (app *localClient) CheckTxAsync(tx []byte) *ReqRes {
 
 func (app *localClient) QueryAsync(req types.RequestQuery) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Query(req)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestQuery(req),
 		types.ToResponseQuery(res),
@@ -103,8 +116,9 @@ func (app *localClient) QueryAsync(req types.RequestQuery) *ReqRes {
 
 func (app *localClient) CommitAsync() *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Commit()
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestCommit(),
 		types.ToResponseCommit(res),
@@ -113,19 +127,20 @@ func (app *localClient) CommitAsync() *ReqRes {
 
 func (app *localClient) InitChainAsync(req types.RequestInitChain) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.InitChain(req)
-	reqRes := app.callback(
+	return app.callback(
 		types.ToRequestInitChain(req),
 		types.ToResponseInitChain(res),
 	)
-	app.mtx.Unlock()
-	return reqRes
 }
 
 func (app *localClient) BeginBlockAsync(req types.RequestBeginBlock) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.BeginBlock(req)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestBeginBlock(req),
 		types.ToResponseBeginBlock(res),
@@ -134,8 +149,9 @@ func (app *localClient) BeginBlockAsync(req types.RequestBeginBlock) *ReqRes {
 
 func (app *localClient) EndBlockAsync(req types.RequestEndBlock) *ReqRes {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.EndBlock(req)
-	app.mtx.Unlock()
 	return app.callback(
 		types.ToRequestEndBlock(req),
 		types.ToResponseEndBlock(res),
@@ -154,64 +170,73 @@ func (app *localClient) EchoSync(msg string) (*types.ResponseEcho, error) {
 
 func (app *localClient) InfoSync(req types.RequestInfo) (*types.ResponseInfo, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Info(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) SetOptionSync(req types.RequestSetOption) (*types.ResponseSetOption, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.SetOption(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) DeliverTxSync(tx []byte) (*types.ResponseDeliverTx, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.DeliverTx(tx)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) CheckTxSync(tx []byte) (*types.ResponseCheckTx, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.CheckTx(tx)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) QuerySync(req types.RequestQuery) (*types.ResponseQuery, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Query(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) CommitSync() (*types.ResponseCommit, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.Commit()
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) InitChainSync(req types.RequestInitChain) (*types.ResponseInitChain, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.InitChain(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) BeginBlockSync(req types.RequestBeginBlock) (*types.ResponseBeginBlock, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.BeginBlock(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 
 func (app *localClient) EndBlockSync(req types.RequestEndBlock) (*types.ResponseEndBlock, error) {
 	app.mtx.Lock()
+	defer app.mtx.Unlock()
+
 	res := app.Application.EndBlock(req)
-	app.mtx.Unlock()
 	return &res, nil
 }
 

abci/client/socket_client.go

@@ -118,8 +118,8 @@ func (cli *socketClient) Error() error {
 // NOTE: callback may get internally generated flush responses.
 func (cli *socketClient) SetResponseCallback(resCb Callback) {
 	cli.mtx.Lock()
-	defer cli.mtx.Unlock()
 	cli.resCb = resCb
+	cli.mtx.Unlock()
 }
 
 //----------------------------------------

consensus/reactor.go

@@ -183,7 +183,11 @@ func (conR *ConsensusReactor) RemovePeer(peer p2p.Peer, reason interface{}) {
 		return
 	}
 	// TODO
-	//peer.Get(PeerStateKey).(*PeerState).Disconnect()
+	// ps, ok := peer.Get(PeerStateKey).(*PeerState)
+	// if !ok {
+	// 	panic(fmt.Sprintf("Peer %v has no state", peer))
+	// }
+	// ps.Disconnect()
 }
 
 // Receive implements Reactor
@@ -214,7 +218,10 @@ func (conR *ConsensusReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte)
 	conR.Logger.Debug("Receive", "src", src, "chId", chID, "msg", msg)
 
 	// Get peer states
-	ps := src.Get(types.PeerStateKey).(*PeerState)
+	ps, ok := src.Get(types.PeerStateKey).(*PeerState)
+	if !ok {
+		panic(fmt.Sprintf("Peer %v has no state", src))
+	}
 
 	switch chID {
 	case StateChannel:
@@ -293,9 +300,9 @@ func (conR *ConsensusReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte)
 		switch msg := msg.(type) {
 		case *VoteMessage:
 			cs := conR.conS
-			cs.mtx.Lock()
+			cs.mtx.RLock()
 			height, valSize, lastCommitSize := cs.Height, cs.Validators.Size(), cs.LastCommit.Size()
-			cs.mtx.Unlock()
+			cs.mtx.RUnlock()
 			ps.EnsureVoteBitArrays(height, valSize)
 			ps.EnsureVoteBitArrays(height-1, lastCommitSize)
 			ps.SetHasVote(msg.Vote)
@@ -428,7 +435,10 @@ func (conR *ConsensusReactor) broadcastHasVoteMessage(vote *types.Vote) {
 	/*
 		// TODO: Make this broadcast more selective.
 		for _, peer := range conR.Switch.Peers().List() {
-			ps := peer.Get(PeerStateKey).(*PeerState)
+			ps, ok := peer.Get(PeerStateKey).(*PeerState)
+			if !ok {
+				panic(fmt.Sprintf("Peer %v has no state", peer))
+			}
 			prs := ps.GetRoundState()
 			if prs.Height == vote.Height {
 				// TODO: Also filter on round?
@@ -826,7 +836,10 @@ func (conR *ConsensusReactor) peerStatsRoutine() {
 				continue
 			}
 			// Get peer state
-			ps := peer.Get(types.PeerStateKey).(*PeerState)
+			ps, ok := peer.Get(types.PeerStateKey).(*PeerState)
+			if !ok {
+				panic(fmt.Sprintf("Peer %v has no state", peer))
+			}
 			switch msg.Msg.(type) {
 			case *VoteMessage:
 				if numVotes := ps.RecordVote(); numVotes%votesToContributeToBecomeGoodPeer == 0 {
@@ -859,7 +872,10 @@ func (conR *ConsensusReactor) StringIndented(indent string) string {
 	s := "ConsensusReactor{\n"
 	s += indent + "  " + conR.conS.StringIndented(indent+"  ") + "\n"
 	for _, peer := range conR.Switch.Peers().List() {
-		ps := peer.Get(types.PeerStateKey).(*PeerState)
+		ps, ok := peer.Get(types.PeerStateKey).(*PeerState)
+		if !ok {
+			panic(fmt.Sprintf("Peer %v has no state", peer))
+		}
 		s += indent + "  " + ps.StringIndented(indent+"  ") + "\n"
 	}
 	s += indent + "}"

consensus/replay_file.go

@@ -58,7 +58,18 @@ func (cs *ConsensusState) ReplayFile(file string, console bool) error {
 	if err != nil {
 		return errors.Errorf("failed to subscribe %s to %v", subscriber, types.EventQueryNewRoundStep)
 	}
-	defer cs.eventBus.Unsubscribe(ctx, subscriber, types.EventQueryNewRoundStep)
+	defer func() {
+		// drain newStepCh to make sure we don't block
+	LOOP:
+		for {
+			select {
+			case <-newStepCh:
+			default:
+				break LOOP
+			}
+		}
+		cs.eventBus.Unsubscribe(ctx, subscriber, types.EventQueryNewRoundStep)
+	}()
 
 	// just open the file for reading, no need to use wal
 	fp, err := os.OpenFile(file, os.O_RDONLY, 0600)
@@ -221,7 +232,18 @@ func (pb *playback) replayConsoleLoop() int {
 			if err != nil {
 				cmn.Exit(fmt.Sprintf("failed to subscribe %s to %v", subscriber, types.EventQueryNewRoundStep))
 			}
-			defer pb.cs.eventBus.Unsubscribe(ctx, subscriber, types.EventQueryNewRoundStep)
+			defer func() {
+				// drain newStepCh to make sure we don't block
+			LOOP:
+				for {
+					select {
+					case <-newStepCh:
+					default:
+						break LOOP
+					}
+				}
+				pb.cs.eventBus.Unsubscribe(ctx, subscriber, types.EventQueryNewRoundStep)
+			}()
 
 			if len(tokens) == 1 {
 				if err := pb.replayReset(1, newStepCh); err != nil {

consensus/state.go

@@ -207,18 +207,16 @@ func (cs *ConsensusState) GetState() sm.State {
 // GetLastHeight returns the last height committed.
 // If there were no blocks, returns 0.
 func (cs *ConsensusState) GetLastHeight() int64 {
-	cs.mtx.Lock()
-	defer cs.mtx.Unlock()
-
+	cs.mtx.RLock()
+	defer cs.mtx.RUnlock()
 	return cs.RoundState.Height - 1
 }
 
 // GetRoundState returns a shallow copy of the internal consensus state.
 func (cs *ConsensusState) GetRoundState() *cstypes.RoundState {
 	cs.mtx.RLock()
-	defer cs.mtx.RUnlock()
-
 	rs := cs.RoundState // copy
+	cs.mtx.RUnlock()
 	return &rs
 }
 
@@ -226,7 +224,6 @@ func (cs *ConsensusState) GetRoundState() *cstypes.RoundState {
 func (cs *ConsensusState) GetRoundStateJSON() ([]byte, error) {
 	cs.mtx.RLock()
 	defer cs.mtx.RUnlock()
-
 	return cdc.MarshalJSON(cs.RoundState)
 }
 
@@ -234,7 +231,6 @@ func (cs *ConsensusState) GetRoundStateJSON() ([]byte, error) {
 func (cs *ConsensusState) GetRoundStateSimpleJSON() ([]byte, error) {
 	cs.mtx.RLock()
 	defer cs.mtx.RUnlock()
-
 	return cdc.MarshalJSON(cs.RoundState.RoundStateSimple())
 }
 
@@ -248,15 +244,15 @@ func (cs *ConsensusState) GetValidators() (int64, []*types.Validator) {
 // SetPrivValidator sets the private validator account for signing votes.
 func (cs *ConsensusState) SetPrivValidator(priv types.PrivValidator) {
 	cs.mtx.Lock()
-	defer cs.mtx.Unlock()
 	cs.privValidator = priv
+	cs.mtx.Unlock()
 }
 
 // SetTimeoutTicker sets the local timer. It may be useful to overwrite for testing.
 func (cs *ConsensusState) SetTimeoutTicker(timeoutTicker TimeoutTicker) {
 	cs.mtx.Lock()
-	defer cs.mtx.Unlock()
 	cs.timeoutTicker = timeoutTicker
+	cs.mtx.Unlock()
 }
 
 // LoadCommit loads the commit for a given height.

evidence/reactor.go

@@ -160,12 +160,15 @@ func (evR *EvidenceReactor) broadcastEvidenceRoutine(peer p2p.Peer) {
 // Returns the message to send the peer, or nil if the evidence is invalid for the peer.
 // If message is nil, return true if we should sleep and try again.
 func (evR EvidenceReactor) checkSendEvidenceMessage(peer p2p.Peer, ev types.Evidence) (msg EvidenceMessage, retry bool) {
-
 	// make sure the peer is up to date
 	evHeight := ev.Height()
 	peerState, ok := peer.Get(types.PeerStateKey).(PeerState)
-	if !ok {
-		evR.Logger.Info("Found peer without PeerState", "peer", peer)
+	if !ok { 
+		// Peer does not have a state yet. We set it in the consensus reactor, but
+		// when we add peer in Switch, the order we call reactors#AddPeer is
+		// different every time due to us using a map. Sometimes other reactors
+		// will be initialized before the consensus reactor. We should wait a few
+		// milliseconds and retry.
 		return nil, true
 	}
 

evidence/reactor_test.go

@@ -165,6 +165,16 @@ func TestReactorSelectiveBroadcast(t *testing.T) {
 
 	// make reactors from statedb
 	reactors := makeAndConnectEvidenceReactors(config, []dbm.DB{stateDB1, stateDB2})
+
+	// set the peer height on each reactor
+	for _, r := range reactors {
+		for _, peer := range r.Switch.Peers().List() {
+			ps := peerState{height1}
+			peer.Set(types.PeerStateKey, ps)
+		}
+	}
+
+	// update the first reactor peer's height to be very small
 	peer := reactors[0].Switch.Peers().List()[0]
 	ps := peerState{height2}
 	peer.Set(types.PeerStateKey, ps)

libs/pubsub/pubsub.go

@@ -30,9 +30,15 @@
 //
 //     s.Subscribe(ctx, sub, qry, out)
 //     defer func() {
-//         for range out {
-//             // drain out to make sure we don't block
-//         }
+//         // drain out to make sure we don't block
+//     LOOP:
+//		     for {
+// 		     	   select {
+// 		     	   case <-out:
+// 		     	   default:
+// 		     	   	   break LOOP
+// 		     	   }
+// 		     }
 //         s.UnsubscribeAll(ctx, sub)
 //     }()
 //     for msg := range out {

mempool/mempool.go

@@ -300,6 +300,7 @@ func (mem *Mempool) TxsWaitChan() <-chan struct{} {
 // CONTRACT: Either cb will get called, or err returned.
 func (mem *Mempool) CheckTx(tx types.Tx, cb func(*abci.Response)) (err error) {
 	mem.proxyMtx.Lock()
+	// use defer to unlock mutex because application (*local client*) might panic
 	defer mem.proxyMtx.Unlock()
 
 	if mem.Size() >= mem.config.Size {

mempool/reactor.go

@@ -133,16 +133,23 @@ func (memR *MempoolReactor) broadcastTxRoutine(peer p2p.Peer) {
 		}
 
 		memTx := next.Value.(*mempoolTx)
+
 		// make sure the peer is up to date
-		height := memTx.Height()
-		if peerState_i := peer.Get(types.PeerStateKey); peerState_i != nil {
-			peerState := peerState_i.(PeerState)
-			peerHeight := peerState.GetHeight()
-			if peerHeight < height-1 { // Allow for a lag of 1 block
-				time.Sleep(peerCatchupSleepIntervalMS * time.Millisecond)
-				continue
-			}
+		peerState, ok := peer.Get(types.PeerStateKey).(PeerState)
+		if !ok {
+			// Peer does not have a state yet. We set it in the consensus reactor, but
+			// when we add peer in Switch, the order we call reactors#AddPeer is
+			// different every time due to us using a map. Sometimes other reactors
+			// will be initialized before the consensus reactor. We should wait a few
+			// milliseconds and retry.
+			time.Sleep(peerCatchupSleepIntervalMS * time.Millisecond)
+			continue
 		}
+		if peerState.GetHeight() < memTx.Height()-1 { // Allow for a lag of 1 block
+			time.Sleep(peerCatchupSleepIntervalMS * time.Millisecond)
+			continue
+		}
+
 		// send memTx
 		msg := &TxMessage{Tx: memTx.tx}
 		success := peer.Send(MempoolChannel, cdc.MustMarshalBinaryBare(msg))

mempool/reactor_test.go

@@ -21,6 +21,14 @@ import (
 	"github.com/tendermint/tendermint/types"
 )
 
+type peerState struct {
+	height int64
+}
+
+func (ps peerState) GetHeight() int64 {
+	return ps.height
+}
+
 // mempoolLogger is a TestingLogger which uses a different
 // color for each validator ("validator" key must exist).
 func mempoolLogger() log.Logger {
@@ -107,6 +115,11 @@ func TestReactorBroadcastTxMessage(t *testing.T) {
 			r.Stop()
 		}
 	}()
+	for _, r := range reactors {
+		for _, peer := range r.Switch.Peers().List() {
+			peer.Set(types.PeerStateKey, peerState{1})
+		}
+	}
 
 	// send a bunch of txs to the first reactor's mempool
 	// and wait for them all to be received in the others

p2p/pex/addrbook.go

@@ -162,10 +162,10 @@ func (a *addrBook) FilePath() string {
 
 // AddOurAddress one of our addresses.
 func (a *addrBook) AddOurAddress(addr *p2p.NetAddress) {
-	a.mtx.Lock()
-	defer a.mtx.Unlock()
 	a.Logger.Info("Add our address to book", "addr", addr)
+	a.mtx.Lock()
 	a.ourAddrs[addr.String()] = struct{}{}
+	a.mtx.Unlock()
 }
 
 // OurAddress returns true if it is our address.
@@ -178,10 +178,10 @@ func (a *addrBook) OurAddress(addr *p2p.NetAddress) bool {
 
 func (a *addrBook) AddPrivateIDs(IDs []string) {
 	a.mtx.Lock()
-	defer a.mtx.Unlock()
 	for _, id := range IDs {
 		a.privateIDs[p2p.ID(id)] = struct{}{}
 	}
+	a.mtx.Unlock()
 }
 
 // AddAddress implements AddrBook
@@ -202,7 +202,7 @@ func (a *addrBook) RemoveAddress(addr *p2p.NetAddress) {
 	if ka == nil {
 		return
 	}
-	a.Logger.Info("Remove address from book", "addr", ka.Addr, "ID", ka.ID())
+	a.Logger.Info("Remove address from book", "addr", addr)
 	a.removeFromAllBuckets(ka)
 }
 
@@ -217,8 +217,8 @@ func (a *addrBook) IsGood(addr *p2p.NetAddress) bool {
 // HasAddress returns true if the address is in the book.
 func (a *addrBook) HasAddress(addr *p2p.NetAddress) bool {
 	a.mtx.Lock()
-	defer a.mtx.Unlock()
 	ka := a.addrLookup[addr.ID]
+	a.mtx.Unlock()
 	return ka != nil
 }
 
@@ -461,13 +461,12 @@ ADDRS_LOOP:
 
 // ListOfKnownAddresses returns the new and old addresses.
 func (a *addrBook) ListOfKnownAddresses() []*knownAddress {
-	a.mtx.Lock()
-	defer a.mtx.Unlock()
-
 	addrs := []*knownAddress{}
+	a.mtx.Lock()
 	for _, addr := range a.addrLookup {
 		addrs = append(addrs, addr.copy())
 	}
+	a.mtx.Unlock()
 	return addrs
 }
 

rpc/client/helpers.go

@@ -69,7 +69,18 @@ func WaitForOneEvent(c EventsClient, evtTyp string, timeout time.Duration) (type
 	}
 
 	// make sure to unregister after the test is over
-	defer c.UnsubscribeAll(ctx, subscriber)
+	defer func() {
+		// drain evts to make sure we don't block
+	LOOP:
+		for {
+			select {
+			case <-evts:
+			default:
+				break LOOP
+			}
+		}
+		c.UnsubscribeAll(ctx, subscriber)
+	}()
 
 	select {
 	case evt := <-evts:

rpc/core/consensus.go

@@ -193,7 +193,10 @@ func DumpConsensusState() (*ctypes.ResultDumpConsensusState, error) {
 	peers := p2pPeers.Peers().List()
 	peerStates := make([]ctypes.PeerStateInfo, len(peers))
 	for i, peer := range peers {
-		peerState := peer.Get(types.PeerStateKey).(*cm.PeerState)
+		peerState, ok := peer.Get(types.PeerStateKey).(*cm.PeerState)
+		if !ok { // peer does not have a state yet
+			continue
+		}
 		peerStateJSON, err := peerState.ToJSON()
 		if err != nil {
 			return nil, err

rpc/core/mempool.go

@@ -8,7 +8,6 @@ import (
 	"github.com/pkg/errors"
 
 	abci "github.com/tendermint/tendermint/abci/types"
-	cmn "github.com/tendermint/tendermint/libs/common"
 	ctypes "github.com/tendermint/tendermint/rpc/core/types"
 	"github.com/tendermint/tendermint/types"
 )
@@ -51,7 +50,7 @@ import (
 func BroadcastTxAsync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 	err := mempool.CheckTx(tx, nil)
 	if err != nil {
-		return nil, fmt.Errorf("Error broadcasting transaction: %v", err)
+		return nil, err
 	}
 	return &ctypes.ResultBroadcastTx{Hash: tx.Hash()}, nil
 }
@@ -94,7 +93,7 @@ func BroadcastTxSync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 		resCh <- res
 	})
 	if err != nil {
-		return nil, fmt.Errorf("Error broadcasting transaction: %v", err)
+		return nil, err
 	}
 	res := <-resCh
 	r := res.GetCheckTx()
@@ -106,8 +105,9 @@ func BroadcastTxSync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 	}, nil
 }
 
-// CONTRACT: only returns error if mempool.BroadcastTx errs (ie. problem with the app)
-// or if we timeout waiting for tx to commit.
+// CONTRACT: only returns error if mempool.CheckTx() errs or if we timeout
+// waiting for tx to commit.
+//
 // If CheckTx or DeliverTx fail, no error will be returned, but the returned result
 // will contain a non-OK ABCI code.
 //
@@ -150,20 +150,31 @@ func BroadcastTxSync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 // |-----------+------+---------+----------+-----------------|
 // | tx        | Tx   | nil     | true     | The transaction |
 func BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
-	// subscribe to tx being committed in block
+	// Subscribe to tx being committed in block.
 	ctx, cancel := context.WithTimeout(context.Background(), subscribeTimeout)
 	defer cancel()
-	deliverTxResCh := make(chan interface{})
+	deliverTxResCh := make(chan interface{}, 1)
 	q := types.EventQueryTxFor(tx)
 	err := eventBus.Subscribe(ctx, "mempool", q, deliverTxResCh)
 	if err != nil {
 		err = errors.Wrap(err, "failed to subscribe to tx")
-		logger.Error("Error on broadcastTxCommit", "err", err)
-		return nil, fmt.Errorf("Error on broadcastTxCommit: %v", err)
+		logger.Error("Error on broadcast_tx_commit", "err", err)
+		return nil, err
 	}
-	defer eventBus.Unsubscribe(context.Background(), "mempool", q)
+	defer func() {
+		// drain deliverTxResCh to make sure we don't block
+	LOOP:
+		for {
+			select {
+			case <-deliverTxResCh:
+			default:
+				break LOOP
+			}
+		}
+		eventBus.Unsubscribe(context.Background(), "mempool", q)
+	}()
 
-	// broadcast the tx and register checktx callback
+	// Broadcast tx and wait for CheckTx result
 	checkTxResCh := make(chan *abci.Response, 1)
 	err = mempool.CheckTx(tx, func(res *abci.Response) {
 		checkTxResCh <- res
@@ -172,40 +183,35 @@ func BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
 		logger.Error("Error on broadcastTxCommit", "err", err)
 		return nil, fmt.Errorf("Error on broadcastTxCommit: %v", err)
 	}
-	checkTxRes := <-checkTxResCh
-	checkTxR := checkTxRes.GetCheckTx()
-	if checkTxR.Code != abci.CodeTypeOK {
-		// CheckTx failed!
+	checkTxResMsg := <-checkTxResCh
+	checkTxRes := checkTxResMsg.GetCheckTx()
+	if checkTxRes.Code != abci.CodeTypeOK {
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   *checkTxR,
+			CheckTx:   *checkTxRes,
 			DeliverTx: abci.ResponseDeliverTx{},
 			Hash:      tx.Hash(),
 		}, nil
 	}
 
-	// Wait for the tx to be included in a block,
-	// timeout after something reasonable.
-	// TODO: configurable?
-	timer := time.NewTimer(60 * 2 * time.Second)
+	// Wait for the tx to be included in a block or timeout.
+	var deliverTxTimeout = 10 * time.Second // TODO: configurable?
 	select {
-	case deliverTxResMsg := <-deliverTxResCh:
+	case deliverTxResMsg := <-deliverTxResCh: // The tx was included in a block.
 		deliverTxRes := deliverTxResMsg.(types.EventDataTx)
-		// The tx was included in a block.
-		deliverTxR := deliverTxRes.Result
-		logger.Info("DeliverTx passed ", "tx", cmn.HexBytes(tx), "response", deliverTxR)
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   *checkTxR,
-			DeliverTx: deliverTxR,
+			CheckTx:   *checkTxRes,
+			DeliverTx: deliverTxRes.Result,
 			Hash:      tx.Hash(),
 			Height:    deliverTxRes.Height,
 		}, nil
-	case <-timer.C:
-		logger.Error("failed to include tx")
+	case <-time.After(deliverTxTimeout):
+		err = errors.New("Timed out waiting for tx to be included in a block")
+		logger.Error("Error on broadcastTxCommit", "err", err)
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   *checkTxR,
+			CheckTx:   *checkTxRes,
 			DeliverTx: abci.ResponseDeliverTx{},
 			Hash:      tx.Hash(),
-		}, fmt.Errorf("Timed out waiting for transaction to be included in a block")
+		}, err
 	}
 }