Description

The UpdateBaseGasPrice computes the following:

baseGasPrice = someValue / (MaxGas \* TargetBlockUtilization)

Currently, at the time of writing, ValidateBasic allows TargetBlockUtilization = 0. A governance-param change to zero triggers a divide-by-zero panic every block.

The panic is caught by

defer func() {
    if rec := recover(); rec != nil {
        logger.Error("Panic recovered in state.UpdateBaseGasPrice", "err", rec)
        s.BaseGasPrice = params.MinBaseGasPrice
        gasPrice = s.BaseGasPrice
    }
}()

so the chain stays alive, but BaseGasPrice is reset to the floor each block, and an error is logged every block.

Impact

This has the following impacts.

• The fee-market mechanism is effectively disabled; the gas price sticks at MinBaseGasPrice.

• Continuous error logs pollute node output and can degrade performance over time.

• A griefing vector is created: one malicious param vote breaks dynamic pricing until another vote passes.

Recommendations

We recommend tightening param validation — enforce 0 < TargetBlockUtilization ≤ 1 and BaseFeeChangeDenom > 0.

Also, add unit tests covering edge values (0, 1, negative, >1).

Remediation

This issue has been acknowledged by AtomOne, and a fix was implemented in PR #166↗.