added nonReentrant modifier to the upgrade function in ZkSync.sol
@@ -120,7 +120,7 @@ contract ZkSync is UpgradeableMaster, Storage, Config, Events, ReentrancyGuard {
/// @notice zkSync contract upgrade. Can be external because Proxy contract intercepts illegal calls of this function.
/// @param upgradeParameters Encoded representation of upgrade parameters
- function upgrade(bytes calldata upgradeParameters) external {
+ function upgrade(bytes calldata upgradeParameters) external nonReentrant {
require(upgradeParameters.length == 0, "af"); // upgrade parameters should be empty
// Convert last verified block from old format to new format
