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ethstorage · Jul 19, 2024 · 74242dc · 74242dc
1 parent 32a338e
commit 74242dc
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/packages/contracts-bedrock/src/dispute/FaultDisputeGameN.sol b/packages/contracts-bedrock/src/dispute/FaultDisputeGameN.sol
@@ -518,8 +518,9 @@ contract FaultDisputeGame is IFaultDisputeGame, Clone, ISemver {
         } else if (_ident == LocalPreimageKey.DISPUTED_OUTPUT_ROOT) {
             // Load the disputed proposal's output root
             Claim disputed;
+            // If the pos is 1, then the rootclaim itself is the output hash.
             if (disputedPos.raw() == 1) {
-                disputed = rootClaim();
+                disputed = disputedRoot;
             } else {
                 disputed = getClaim(disputedRoot.raw(), disputedPos, _daItem);
             }
@@ -1154,14 +1155,15 @@ contract FaultDisputeGame is IFaultDisputeGame, Clone, ISemver {
             : _firstValidRightIndex(_pos.traceAncestorBounded(SPLIT_DEPTH), N_BITS);
 
         uint256 offset = ancestorPos_.raw() % (1 << N_BITS);
-        if (MAX_ATTACK_BRANCH == offset) {
+        // If ancestorPos_.raw() == 1 (rootclaim), we don't offset it
+        if (MAX_ATTACK_BRANCH == offset || ancestorPos_.raw() == 1) {
             offset = 0;
         }
         uint256 traceAncestorPosValue = ancestorPos_.raw() - offset;
         // Walk up the DAG to find a claim that commits to the same trace index as `_pos`. It is
         // guaranteed that such a claim exists.
         ClaimData storage ancestor_ = claimData[_start];
-        if (traceAncestorPosValue == 0) {
+        if (traceAncestorPosValue == 1) {
             ancestorClaimRoot_ = rootClaim();
         } else {
             while (ancestor_.position.raw() != traceAncestorPosValue) {