Submitted by tensors
Because mantissa calculations are not used in this case to account for decimals, the arithmetic can zero out the number of shares or tokens that should be given.
For example, say I deposit 1 token, expecting 1 share in return. On L95, if the totalUnderlyingAssets is increased to be larger than the number of total shares, then the division would output 0 and I wouldnt get any shares.
Recommend  implementing mantissa calculations like in the contract for the AAVE  yield.
PierrickGT (PoolTogether) confirmed and patched:
