Possible Dos Because Unbounded Loop Can Run Out Of Gas

Submitted by (4) minhquanym, also found by berndartmueller, Chom, and scaraven

Summary:

https://code4rena.com/reports/2022-08-rigor/#m-10-possible-dos-in-lendtoproject-and-togglelendingneeded-function-because-unbounded-loop-can-run-out-of-gas

In Project contract, the lendToProject() function might not be available to be called if there are a lot of Task in tasks[] list of project. It means that the project cannot be funded by either builder or community owner.

This can happen because lendToProject() used projectCost() function. And the loop in projectCost() did not have a mechanism to stop, it’s only based on the length taskCount, and may take all the gas limit. If the gas limit is reached, this transaction will fail or revert.

Also, there should be a task limit.

Mitigation:

Consider keeping value of projectCost() in a storage variable and update it when a task is added or updated accordingly.