fix(flow-limit): handle large flow limit values

contracts/interfaces/IFlowLimit.sol

@@ -8,6 +8,7 @@ pragma solidity ^0.8.0;
  */
 interface IFlowLimit {
     error FlowLimitExceeded(uint256 limit, uint256 flowAmount, address tokenManager);
+    error InvalidFlowLimit(uint256 flowLimit, bytes32 tokenId);
 
     event FlowLimitSet(bytes32 indexed tokenId, address operator, uint256 flowLimit_);
 

contracts/utils/FlowLimit.sol

@@ -29,10 +29,14 @@ contract FlowLimit is IFlowLimit {
 
     /**
      * @notice Internal function to set the flow limit.
-     * @param flowLimit_ The value to set the flow limit to.
+     * @param flowLimit_ The value to set the flow limit to. Must not be set to `uint256.max`.
+     * Only the operator can set the flow limit for their own token; however, an incorrect setting
+     * may result in a denial of service due to potential arithmetic underflow or overflow.
      * @param tokenId The id of the token to set the flow limit for.
      */
     function _setFlowLimit(uint256 flowLimit_, bytes32 tokenId) internal {
+        if (flowLimit_ == type(uint256).max) revert InvalidFlowLimit(flowLimit_, tokenId);
+
         assembly {
             sstore(FLOW_LIMIT_SLOT, flowLimit_)
         }

test/InterchainTokenService.js

@@ -2721,6 +2721,15 @@ describe('Interchain Token Service', () => {
             await tokenManager.setFlowLimit(flowLimit).then((tx) => tx.wait);
         });
 
+        it('Should be reverted setting invalid flow limit', async () => {
+            const invalidFlowLimit = MaxUint256;
+
+            await expectRevert((gasOptions) => tokenManager.setFlowLimit(invalidFlowLimit, gasOptions), tokenManager, 'InvalidFlowLimit', [
+                invalidFlowLimit,
+                tokenId,
+            ]);
+        });
+
         it('Should be able to send token only if it does not trigger the mint limit', async () => {
             await service.interchainTransfer(tokenId, destinationChain, destinationAddress, sendAmount, '0x', 0).then((tx) => tx.wait);