fix iter value safe copy

.gitignore

@@ -30,3 +30,5 @@ go.work.sum
 # Editor/IDE
 # .idea/
 # .vscode/
+
+__debug_bin*

database/leveldb/reactions.go

@@ -199,10 +199,7 @@ func (r *reactions) addHot(k []byte, delta int) {
 	}
 
 	cnt.mu.Lock()
-	val := int64(cnt.val) + int64(delta)
-	if val < 0 {
-		val = 0
-	}
+	val := max(int64(cnt.val)+int64(delta), 0)
 	cnt.val = uint64(val)
 
 	if !cnt.jobRunning {

database/leveldb/subscriptions.go

@@ -78,9 +78,12 @@ func (s *subscriptions) OfDomestic(user string, limit, offset int) ([]database.S
 		keyParts := bytes.Split(iter.Key(), []byte(":"))
 		targetEmail := string(keyParts[len(keyParts)-1])
 
+		sig := make([]byte, len(iter.Value()))
+		copy(sig, iter.Value())
+
 		subs = append(subs, database.Subscription{
 			User:      targetEmail,
-			Signature: iter.Value(),
+			Signature: sig,
 		})
 
 		if len(subs) >= limit {
@@ -108,9 +111,12 @@ func (s *subscriptions) ToForeign(targetEmail string, limit, offset int) ([]data
 		keyParts := bytes.Split(iter.Key(), []byte(":"))
 		subscriberName := string(keyParts[len(keyParts)-1])
 
+		sig := make([]byte, len(iter.Value()))
+		copy(sig, iter.Value())
+
 		subs = append(subs, database.Subscription{
 			User:      subscriberName,
-			Signature: iter.Value(),
+			Signature: sig,
 		})
 
 		if len(subs) >= limit {
@@ -147,10 +153,7 @@ func (s *subscriptions) addHot(k []byte, delta int) {
 	}
 
 	cnt.mu.Lock()
-	val := int64(cnt.val) + int64(delta)
-	if val < 0 {
-		val = 0
-	}
+	val := max(int64(cnt.val)+int64(delta), 0)
 	cnt.val = uint64(val)
 
 	if !cnt.jobRunning {