x/opchild/types/params.go (2)

13-13: Add documentation for the DefaultHookMaxGas constant.

Please add a comment explaining why 1,000,000 was chosen as the default value for hook max gas. This helps future maintainers understand the reasoning behind this specific limit.

---

Line range hint 51-70: Add validation for HookMaxGas in the Validate method.

The Validate method should check if HookMaxGas is within acceptable bounds to prevent potential issues with hook execution.

Consider adding validation like this:

 func (p Params) Validate(ac address.Codec) error {
     if _, err := ac.StringToBytes(p.Admin); err != nil {
         return err
     }
     for _, be := range p.BridgeExecutors {
         if _, err := ac.StringToBytes(be); err != nil {
             return err
         }
     }

     if err := p.MinGasPrices.Validate(); err != nil {
         return err
     }

     if p.MaxValidators == 0 {
         return ErrZeroMaxValidators
     }

+    if p.HookMaxGas == 0 {
+        return fmt.Errorf("hook max gas cannot be zero")
+    }
+
     // Validate fee whitelist addresses
     for _, addr := range p.FeeWhitelist {
         if _, err := ac.StringToBytes(addr); err != nil {
             return err
         }
     }

     return nil
 }

proto/opinit/opchild/v1/types.proto (1)

50-51: Enhance the field documentation.

The current documentation could be more descriptive. Consider adding:

• Default value
• Acceptable range/constraints
• Impact on hook execution
• Relationship with system-wide gas limits

Example:

-  // Max gas for hook execution of `MsgFinalizeTokenDeposit`
+  // Maximum gas limit for hook execution during MsgFinalizeTokenDeposit processing.
+  // Must be positive and not exceed the block gas limit.
+  // Default: 1000000 gas units.
+  // Note: Hook execution will fail if gas consumption exceeds this limit.

x/opchild/keeper/msg_server_test.go (3)

563-618: LGTM! Comprehensive test coverage for out-of-gas scenario.

The test thoroughly validates the behavior when a hook fails due to insufficient gas by:

1. Setting an extremely low gas limit (1)
2. Verifying the failure event attributes
3. Checking that no token transfers occurred
4. Ensuring proper error handling

Consider adding a comment explaining why the gas limit is set to 1, as it might not be immediately obvious that this is intentionally set to an extremely low value to force the out-of-gas condition.

 params.HookMaxGas = 1
+// Set an extremely low gas limit to force an out-of-gas condition
 input.OPChildKeeper.SetParams(ctx, params)

---

595-597: Consider adding gas meter validation.

The test sets up a gas meter with 2,000,000 gas units but doesn't verify the gas consumption. Consider adding assertions to validate that the hook execution attempted to consume more gas than the 1-unit limit.

---

601-609: Enhance error message validation.

While the test verifies the presence of "panic:" in the error message, it would be more robust to validate the specific out-of-gas error message to ensure the failure is happening for the expected reason.

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#!/bin/bash
# Search for tests validating gas consumption behavior
rg -l "GasMeter|ConsumeGas" --type go

# Look for potential gas-related test cases
ast-grep --pattern 'func Test$_.*Gas.*\(.*testing\.T\).*{
  $$$
}'

#!/bin/bash
# Check the gas consumption implementation in deposit.go
rg -A 10 "GasMeter|ConsumeGas" x/opchild/keeper/deposit.go

# Check test implementations for gas-related scenarios
rg -A 10 "GasMeter|ConsumeGas" x/opchild/keeper/msg_server_test.go

# Look for any gas-related test setup or assertions
ast-grep --pattern 'func \($_\) Test.*\(t \*testing.T\) {
  $$$
  GasMeter
  $$$
}'

#!/bin/bash
# Description: Verify hook execution implementation across the codebase
# Test: Search for all hook execution calls to ensure consistent gas limit usage

# Check hook execution implementation
echo "Checking hook execution implementation..."
ast-grep --pattern 'handleBridgeHook($ctx, $data, $gas)'

# Check test coverage for different gas scenarios
echo "Checking test coverage for gas scenarios..."
rg -A 10 "Test.*Hook.*Gas" 

x/opchild/keeper/deposit.go (4)

13-16: Enhance the error message for better debugging.

While the validation is good, consider making the error message more descriptive to aid in debugging.

-		return false, "hook max gas is zero"
+		return false, "invalid hook_max_gas: value must be greater than zero"

---

18-22: Consider adding minimum gas validation.

While the code correctly caps the maximum gas, it doesn't ensure there's enough gas for minimal hook execution. Consider adding a minimum gas threshold check.

 	if hookMaxGas == 0 {
 		return false, "hook max gas is zero"
 	}
+
+	// Ensure minimum gas for hook execution
+	const minHookGas uint64 = 20_000 // adjust based on minimal hook requirements
+	if hookMaxGas < minHookGas {
+		return false, fmt.Sprintf("hook_max_gas too low: minimum required is %d", minHookGas)
+	}

---

37-38: Enhance the comment for better context.

While the implementation is correct, consider making the comment more descriptive to explain the purpose of the gas meter replacement.

-	// use new gas meter with the hook max gas limit
+	// Replace gas meter to enforce hook_max_gas limit and prevent excessive gas consumption during hook execution

---

Line range hint 13-39: Consider monitoring and tuning gas parameters.

The gas management implementation is solid, but consider:

1. Adding metrics to monitor hook gas usage in production
2. Making the minimum gas requirement configurable via chain parameters
3. Documenting recommended gas values in the chain documentation

This will help operators tune these parameters based on real-world usage patterns.

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Review profile: CHILL