From 684facedb821d3026c870eaa80bc6bc9ec79c645 Mon Sep 17 00:00:00 2001
From: Felix Lange <fjl@users.noreply.github.com>
Date: Thu, 24 Jan 2019 13:40:37 +0100
Subject: light: fix disableCheckFreq locking (#18515)
This change unbreaks the build and removes racy access to
disableCheckFreq. Even though the field is set while holding
the lock, it was read outside of the protected section.
---
light/lightchain.go | 32 +++++++++++++-------------------
1 file changed, 13 insertions(+), 19 deletions(-)
diff --git a/light/lightchain.go b/light/lightchain.go
index 47161c9ef..3691f1304 100644
--- a/light/lightchain.go
+++ b/light/lightchain.go
@@ -35,7 +35,7 @@ import (
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
- "github.com/hashicorp/golang-lru"
+ lru "github.com/hashicorp/golang-lru"
)
var (
@@ -50,6 +50,7 @@ type LightChain struct {
hc *core.HeaderChain
indexerConfig *IndexerConfig
chainDb ethdb.Database
+ engine consensus.Engine
odr OdrBackend
chainFeed event.Feed
chainSideFeed event.Feed
@@ -57,21 +58,18 @@ type LightChain struct {
scope event.SubscriptionScope
genesisBlock *types.Block
- chainmu sync.RWMutex
-
bodyCache *lru.Cache // Cache for the most recent block bodies
bodyRLPCache *lru.Cache // Cache for the most recent block bodies in RLP encoded format
blockCache *lru.Cache // Cache for the most recent entire blocks
+ chainmu sync.RWMutex // protects header inserts
quit chan struct{}
- running int32 // running must be called automically
- // procInterrupt must be atomically called
- procInterrupt int32 // interrupt signaler for block processing
- wg sync.WaitGroup
-
- engine consensus.Engine
+ wg sync.WaitGroup
- disableCheckFreq bool
+ // Atomic boolean switches:
+ running int32 // whether LightChain is running or stopped
+ procInterrupt int32 // interrupts chain insert
+ disableCheckFreq int32 // disables header verification
}
// NewLightChain returns a fully initialised light chain using information
@@ -356,7 +354,7 @@ func (self *LightChain) postChainEvents(events []interface{}) {
// In the case of a light chain, InsertHeaderChain also creates and posts light
// chain events when necessary.
func (self *LightChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error) {
- if self.disableCheckFreq {
+ if atomic.LoadInt32(&self.disableCheckFreq) == 1 {
checkFreq = 0
}
start := time.Now()
@@ -532,16 +530,12 @@ func (self *LightChain) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEven
return self.scope.Track(new(event.Feed).Subscribe(ch))
}
-//DisableCheckFreq disables header validation. It needs for ULC
+// DisableCheckFreq disables header validation. This is used for ultralight mode.
func (self *LightChain) DisableCheckFreq() {
- self.mu.Lock()
- defer self.mu.Unlock()
- self.disableCheckFreq = true
+ atomic.StoreInt32(&self.disableCheckFreq, 1)
}
-//EnableCheckFreq enables header validation
+// EnableCheckFreq enables header validation.
func (self *LightChain) EnableCheckFreq() {
- self.mu.Lock()
- defer self.mu.Unlock()
- self.disableCheckFreq = false
+ atomic.StoreInt32(&self.disableCheckFreq, 0)
}
--
cgit v1.2.3