diff --git a/docker/script/run_format.sh b/docker/script/run_format.sh
index 36d371a22..77458ac38 100755
--- a/docker/script/run_format.sh
+++ b/docker/script/run_format.sh
@@ -15,7 +15,7 @@ popd
 
 export PATH=$PATH:/go/bin
 
-for subdir in blockcache storage cli lcnode
+for subdir in proto blockcache storage cli lcnode
 do
     pushd ${CurrentPath}/../../${subdir}
     go generate ./...
diff --git a/proto/admin_proto.go b/proto/admin_proto.go
index 6bf3bee75..18139ba4f 100644
--- a/proto/admin_proto.go
+++ b/proto/admin_proto.go
@@ -999,12 +999,12 @@ type ClientReportLimitInfo struct {
 	FactorMap map[uint32]*ClientLimitInfo
 	Host      string
 	Status    uint8
-	reserved  string
+	_         string // reserved
 }
 
 func NewClientReportLimitInfo() *ClientReportLimitInfo {
 	return &ClientReportLimitInfo{
-		FactorMap: make(map[uint32]*ClientLimitInfo, 0),
+		FactorMap: make(map[uint32]*ClientLimitInfo),
 	}
 }
 
@@ -1015,13 +1015,13 @@ type LimitRsp2Client struct {
 	HitTriggerCnt uint8
 	FactorMap     map[uint32]*ClientLimitInfo
 	Magnify       map[uint32]uint32
-	reserved      string
+	_             string // reserved
 }
 
 func NewLimitRsp2Client() *LimitRsp2Client {
 	limit := &LimitRsp2Client{
-		FactorMap: make(map[uint32]*ClientLimitInfo, 0),
-		Magnify:   make(map[uint32]uint32, 0),
+		FactorMap: make(map[uint32]*ClientLimitInfo),
+		Magnify:   make(map[uint32]uint32),
 	}
 	return limit
 }
diff --git a/proto/extent_key.go b/proto/extent_key.go
index baaeea1c3..8ca77131c 100644
--- a/proto/extent_key.go
+++ b/proto/extent_key.go
@@ -239,11 +239,6 @@ func (k *ExtentKey) MarshalBinaryExt(data []byte) {
 
 // MarshalBinary marshals the binary format of the extent key.
 func (k *ExtentKey) MarshalBinary(v3 bool) ([]byte, error) {
-	extLen := ExtentLength
-	if v3 {
-		extLen += ExtentVerFieldSize
-	}
-
 	buf := bytes.NewBuffer(make([]byte, 0, ExtentLength))
 	if err := binary.Write(buf, binary.BigEndian, k.FileOffset); err != nil {
 		return nil, err
diff --git a/proto/lifecycle.go b/proto/lifecycle.go
index e84aa1ff1..4b4b2f563 100644
--- a/proto/lifecycle.go
+++ b/proto/lifecycle.go
@@ -122,7 +122,7 @@ type BatchDentries struct {
 
 func NewBatchDentries() *BatchDentries {
 	return &BatchDentries{
-		dentries: make(map[uint64]*ScanDentry, 0),
+		dentries: make(map[uint64]*ScanDentry),
 	}
 }
 
@@ -146,6 +146,6 @@ func (f *BatchDentries) BatchGetAndClear() (map[uint64]*ScanDentry, []uint64) {
 	for i := range f.dentries {
 		inodes = append(inodes, i)
 	}
-	f.dentries = make(map[uint64]*ScanDentry, 0)
+	f.dentries = make(map[uint64]*ScanDentry)
 	return dentries, inodes
 }
diff --git a/proto/mount_options.go b/proto/mount_options.go
index 0640bb9fe..710b2e3be 100644
--- a/proto/mount_options.go
+++ b/proto/mount_options.go
@@ -187,7 +187,7 @@ func ParseMountOptions(opts []MountOption, cfg *config.Config) {
 					opts[i].value = v
 				}
 			}
-			fmt.Println(fmt.Sprintf("keyword[%v] value[%v] type[%T]", opts[i].keyword, opts[i].value, v))
+			fmt.Printf("keyword[%v] value[%v] type[%T]\n", opts[i].keyword, opts[i].value, v)
 
 		case int64:
 			if opts[i].cmdlineValue != "" {
@@ -199,7 +199,7 @@ func ParseMountOptions(opts []MountOption, cfg *config.Config) {
 					opts[i].value = v
 				}
 			}
-			fmt.Println(fmt.Sprintf("keyword[%v] value[%v] type[%T]", opts[i].keyword, opts[i].value, v))
+			fmt.Printf("keyword[%v] value[%v] type[%T]\n", opts[i].keyword, opts[i].value, v)
 
 		case bool:
 			if opts[i].cmdlineValue != "" {
@@ -211,10 +211,10 @@ func ParseMountOptions(opts []MountOption, cfg *config.Config) {
 					opts[i].value = v
 				}
 			}
-			fmt.Println(fmt.Sprintf("keyword[%v] value[%v] type[%T]", opts[i].keyword, opts[i].value, v))
+			fmt.Printf("keyword[%v] value[%v] type[%T]\n", opts[i].keyword, opts[i].value, v)
 
 		default:
-			fmt.Println(fmt.Sprintf("keyword[%v] unknown type[%T]", opts[i].keyword, v))
+			fmt.Printf("keyword[%v] unknown type[%T]\n", opts[i].keyword, v)
 		}
 	}
 }
diff --git a/proto/packet.go b/proto/packet.go
index 2f97ae176..2a108c002 100644
--- a/proto/packet.go
+++ b/proto/packet.go
@@ -707,14 +707,10 @@ func (p *Packet) MarshalHeader(out []byte) {
 	if p.Opcode == OpRandomWriteVer || p.ExtentType&MultiVersionFlag > 0 {
 		binary.BigEndian.PutUint64(out[util.PacketHeaderSize:util.PacketHeaderSize+8], p.VerSeq)
 	}
-	return
 }
 
 func (p *Packet) IsVersionList() bool {
-	if p.ExtentType&VersionListFlag == VersionListFlag {
-		return true
-	}
-	return false
+	return p.ExtentType&VersionListFlag == VersionListFlag
 }
 
 // UnmarshalHeader unmarshals the packet header.
@@ -943,9 +939,6 @@ func (p *Packet) ReadFromConnWithVer(c net.Conn, timeoutSec int) (err error) {
 		}
 	}
 
-	if p.Size < 0 {
-		return syscall.EBADMSG
-	}
 	size := p.Size
 	if p.IsReadOperation() && p.ResultCode == OpInitResultCode {
 		size = 0
@@ -990,9 +983,6 @@ func (p *Packet) ReadFromConn(c net.Conn, timeoutSec int) (err error) {
 		}
 	}
 
-	if p.Size < 0 {
-		return syscall.EBADMSG
-	}
 	size := p.Size
 	if (p.Opcode == OpRead || p.Opcode == OpStreamRead || p.Opcode == OpExtentRepairRead || p.Opcode == OpStreamFollowerRead) && p.ResultCode == OpInitResultCode {
 		size = 0
diff --git a/proto/perm_action.go b/proto/perm_action.go
index e0b6022f0..2c841f394 100644
--- a/proto/perm_action.go
+++ b/proto/perm_action.go
@@ -21,8 +21,8 @@ import (
 )
 
 var (
-	actionRegexp       = regexp.MustCompile("^action:((oss:(\\w+))|(posix:(\\w)+))$")
-	actionPrefixRegexp = regexp.MustCompile("^action:((oss)|(posix)):")
+	actionRegexp       = regexp.MustCompile(`^action:((oss:(\w+))|(posix:(\w)+))$`)
+	actionPrefixRegexp = regexp.MustCompile(`^action:((oss)|(posix)):`)
 )
 
 type Action string
@@ -380,12 +380,12 @@ const (
 )
 
 var (
-	permRegexp                = regexp.MustCompile("^perm:((builtin:((.*/*)([^/]*):*)(Writable|ReadOnly))|(custom:(\\w)+))$")
-	builtinPermRegexp         = regexp.MustCompile("^perm:builtin:((.*/*)([^/]*):*)(Writable|ReadOnly)$")
-	builtinWritablePermRegexp = regexp.MustCompile("^perm:builtin:((.*/*)([^/]*):*)Writable$")
-	builtinReadOnlyPermRegexp = regexp.MustCompile("^perm:builtin:((.*/*)([^/]*):*)ReadOnly$")
-	customPermRegexp          = regexp.MustCompile("^perm:custom:(\\w)+$")
-	subdirRegexp              = regexp.MustCompile("((.*/*)([^/]*)):(Writable|ReadOnly)$")
+	permRegexp                = regexp.MustCompile(`^perm:((builtin:((.*/*)([^/]*):*)(Writable|ReadOnly))|(custom:(\w)+))$`)
+	builtinPermRegexp         = regexp.MustCompile(`^perm:builtin:((.*/*)([^/]*):*)(Writable|ReadOnly)$`)
+	builtinWritablePermRegexp = regexp.MustCompile(`^perm:builtin:((.*/*)([^/]*):*)Writable$`)
+	builtinReadOnlyPermRegexp = regexp.MustCompile(`^perm:builtin:((.*/*)([^/]*):*)ReadOnly$`)
+	customPermRegexp          = regexp.MustCompile(`^perm:custom:(\w)+$`)
+	subdirRegexp              = regexp.MustCompile(`((.*/*)([^/]*)):(Writable|ReadOnly)$`)
 )
 
 func ParsePermission(value string) Permission {
diff --git a/proto/transaction.go b/proto/transaction.go
index 632190560..b6ee78163 100644
--- a/proto/transaction.go
+++ b/proto/transaction.go
@@ -607,8 +607,8 @@ const initTmId = -1
 func NewTransactionInfo(timeout int64, txType uint32) *TransactionInfo {
 	return &TransactionInfo{
 		Timeout:       timeout,
-		TxInodeInfos:  make(map[uint64]*TxInodeInfo, 0),
-		TxDentryInfos: make(map[string]*TxDentryInfo, 0),
+		TxInodeInfos:  make(map[uint64]*TxInodeInfo),
+		TxDentryInfos: make(map[string]*TxDentryInfo),
 		TmID:          initTmId,
 		TxType:        txType,
 		State:         TxStateInit,
@@ -616,10 +616,7 @@ func NewTransactionInfo(timeout int64, txType uint32) *TransactionInfo {
 }
 
 func (txInfo *TransactionInfo) IsInitialized() bool {
-	if txInfo.TxID != "" {
-		return true
-	}
-	return false
+	return txInfo.TxID != ""
 }
 
 func (txInfo *TransactionInfo) String() string {
diff --git a/proto/user_proto.go b/proto/user_proto.go
index 60e94bea6..d280ba8fc 100644
--- a/proto/user_proto.go
+++ b/proto/user_proto.go
@@ -187,7 +187,6 @@ func (policy *UserPolicy) IsAuthorizedS3(volume, api string) bool {
 		if builtinReadOnlyPermRegexp.MatchString(perm) && !contain(api, WriteS3Api) {
 			return true
 		}
-		return false
 	}
 	return false
 }
diff --git a/proto/version.go b/proto/version.go
index 335743308..e17b7e36a 100644
--- a/proto/version.go
+++ b/proto/version.go
@@ -5,6 +5,9 @@ import (
 	"runtime"
 )
 
+//TODO: remove this later.
+//go:generate golangci-lint run --issues-exit-code=1 -D errcheck -E bodyclose .
+
 var (
 	Version    string
 	CommitID   string