From 319ecb3005fe319369f3be91db0fc8605ee2706b Mon Sep 17 00:00:00 2001
From: Yawning Angel <yawning@schwanenlied.me>
Date: Fri, 7 Jun 2019 07:26:47 +0000
Subject: [PATCH] libs/db: Fix the BoltDB Get and Iterator

BoltDB's accessors will return slices that are only valid for the
lifetime of the transaction.  This adds copies where required to prevent
hard to debug crashes (among other things).
---
 CHANGELOG_PENDING.md |  1 +
 libs/db/boltdb.go    | 12 +++++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG_PENDING.md b/CHANGELOG_PENDING.md
index 286c1cb02..f96956e72 100644
--- a/CHANGELOG_PENDING.md
+++ b/CHANGELOG_PENDING.md
@@ -29,3 +29,4 @@
 
 ### BUG FIXES:
 - [libs/db] Fixed the BoltDB backend's Batch.Delete implementation (@Yawning)
+- [libs/db] Fixed the BoltDB backend's Get and Iterator implementation (@Yawning)
diff --git a/libs/db/boltdb.go b/libs/db/boltdb.go
index 6b44c5560..30501dd82 100644
--- a/libs/db/boltdb.go
+++ b/libs/db/boltdb.go
@@ -66,7 +66,9 @@ func (bdb *BoltDB) Get(key []byte) (value []byte) {
 	key = nonEmptyKey(nonNilBytes(key))
 	err := bdb.db.View(func(tx *bbolt.Tx) error {
 		b := tx.Bucket(bucket)
-		value = b.Get(key)
+		if v := b.Get(key); v != nil {
+			value = append([]byte{}, v...)
+		}
 		return nil
 	})
 	if err != nil {
@@ -312,12 +314,16 @@ func (itr *boltDBIterator) Next() {
 
 func (itr *boltDBIterator) Key() []byte {
 	itr.assertIsValid()
-	return itr.currentKey
+	return append([]byte{}, itr.currentKey...)
 }
 
 func (itr *boltDBIterator) Value() []byte {
 	itr.assertIsValid()
-	return itr.currentValue
+	var value []byte
+	if itr.currentValue != nil {
+		value = append([]byte{}, itr.currentValue...)
+	}
+	return value
 }
 
 func (itr *boltDBIterator) Close() {