From 7205366c9f85bbfcf86ac78efcd005bb10dfc5fe Mon Sep 17 00:00:00 2001
From: Martin Holst Swende <martin@swende.se>
Date: Wed, 11 Apr 2018 15:03:49 +0200
Subject: [PATCH] core/state: fix ripemd-cornercase in Copy

---
 core/state/statedb.go | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/core/state/statedb.go b/core/state/statedb.go
index 97c6e4a01..3ae6843d8 100644
--- a/core/state/statedb.go
+++ b/core/state/statedb.go
@@ -471,8 +471,14 @@ func (self *StateDB) Copy() *StateDB {
 	}
 	// Copy the dirty states, logs, and preimages
 	for addr := range self.journal.dirties {
-		state.stateObjects[addr] = self.stateObjects[addr].deepCopy(state)
-		state.stateObjectsDirty[addr] = struct{}{}
+		// As documented [here](https://github.com/ethereum/go-ethereum/pull/16485#issuecomment-380438527),
+		// and in the Finalise-method, there is a case where an object is in the journal but not
+		// in the stateObjects: OOG after touch on ripeMD prior to Byzantium. Thus, we need to check for
+		// nil
+		if object, exist := self.stateObjects[addr]; exist {
+			state.stateObjects[addr] = object.deepCopy(state)
+			state.stateObjectsDirty[addr] = struct{}{}
+		}
 	}
 	// Above, we don't copy the actual journal. This means that if the copy is copied, the
 	// loop above will be a no-op, since the copy's journal is empty.