Aave DIVA Wrapper

Description:
The _registerCollateralToken function uses approve instead of safeApprove for ERC20 token approvals. This creates compatibility issues with non-standard ERC20 tokens (e.g., USDT) that require allowances to be reset to zero before setting a new value.

Root Cause:

• Direct Use of approve: The code uses _collateralTokenContract.approve(_aaveV3Pool, type(uint256).max), which does not handle tokens that revert on non-zero allowance changes.

• Non-Compliant ERC20 Tokens: Tokens like USDT on Ethereum enforce a "zero-reset" before increasing allowance, causing transactions to revert if not followed.

Impact:

• Denial of Service (DoS): Collateral tokens requiring allowance resets (e.g., USDT) cannot be registered, breaking core functionality.

• Reduced Protocol Utility: Inability to support widely used Aave collateral assets (Medium Severity).

Recommendation:
Replace approve with OpenZeppelin’s safeApprove to handle non-standard tokens: