diff --git a/accounts/keystore/keystore.go b/accounts/keystore/keystore.go
index 5c978cf0b4..df3dda60b6 100644
--- a/accounts/keystore/keystore.go
+++ b/accounts/keystore/keystore.go
@@ -312,11 +312,10 @@ func (ks *KeyStore) Unlock(a accounts.Account, passphrase string) error {
 // Lock removes the private key with the given address from memory.
 func (ks *KeyStore) Lock(addr common.Address) error {
 	ks.mu.Lock()
-	if unl, found := ks.unlocked[addr]; found {
-		ks.mu.Unlock()
+	unl, found := ks.unlocked[addr]
+	ks.mu.Unlock()
+	if found {
 		ks.expire(addr, unl, time.Duration(0)*time.Nanosecond)
-	} else {
-		ks.mu.Unlock()
 	}
 	return nil
 }
diff --git a/accounts/scwallet/hub.go b/accounts/scwallet/hub.go
index 5f1f369ca2..1b1899dc8e 100644
--- a/accounts/scwallet/hub.go
+++ b/accounts/scwallet/hub.go
@@ -95,6 +95,7 @@ func (hub *Hub) readPairings() error {
 		}
 		return err
 	}
+	defer pairingFile.Close()
 
 	pairingData, err := io.ReadAll(pairingFile)
 	if err != nil {
diff --git a/cmd/geth/logging_test.go b/cmd/geth/logging_test.go
index b5ce03f4b8..f426b138bb 100644
--- a/cmd/geth/logging_test.go
+++ b/cmd/geth/logging_test.go
@@ -73,6 +73,7 @@ func testConsoleLogging(t *testing.T, format string, tStart, tEnd int) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer readFile.Close()
 	wantLines := split(readFile)
 	haveLines := split(bytes.NewBuffer(haveB))
 	for i, want := range wantLines {
@@ -109,6 +110,7 @@ func TestJsonLogging(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer readFile.Close()
 	wantLines := split(readFile)
 	haveLines := split(bytes.NewBuffer(haveB))
 	for i, wantLine := range wantLines {
diff --git a/core/mkalloc.go b/core/mkalloc.go
index 201c2fe7de..cc4955f038 100644
--- a/core/mkalloc.go
+++ b/core/mkalloc.go
@@ -101,6 +101,7 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
+	defer file.Close()
 	if err := json.NewDecoder(file).Decode(g); err != nil {
 		panic(err)
 	}