Unbound Loops

A detector that analyzes loop conditions and control flow to ensure loops have proper termination criteria.

Why is it bad?

An unbounded loop can be problematic for several reasons:

• Unexpected Behavior: Without a defined termination, loops can lead to unpredictable contract behavior and make debugging difficult.
• Out-of-gas Attacks: Continuous looping without termination can lead to out-of-gas attacks.
• DoS Attacks: Malicious actors can exploit unbounded loops to create denial-of-service attacks, impacting contract's availability.

Example

let x: Int = 10;
while (x > 0) {
  // Bad: x is not changed due looping
  send(SendParameters{ to: sender(), ... });
}

Use instead:

let x: Int = 10;
while (x > 0) {
  send(SendParameters{ to: sender(), ... });
  x = x - 1;
}