Submission Details
Severity:
Missing Return Value from TSwapPool::swapExactInput causes users always recieve default value as output.
Summary
The swapExactInput function is intended to return the actual amount of tokens purchased by the caller. However, despite declaring a named return value output, it neither assigns a value to output nor uses an explicit return statement.
Impact
The return value will always be 0, giving incorrect information to the caller.
Tools Used
Manual Review
Recommendations
{
uint256 inputReserves = inputToken.balanceOf(address(this));
uint256 outputReserves = outputToken.balanceOf(address(this));
- uint256 outputAmount = getOutputAmountBasedOnInput(inputAmount, inputReserves, outputReserves);
+ output = getOutputAmountBasedOnInput(inputAmount, inputReserves, outputReserves);
- if (output < minOutputAmount) {
- revert TSwapPool__OutputTooLow(outputAmount, minOutputAmount);
+ if (output < minOutputAmount) {
+ revert TSwapPool__OutputTooLow(outputAmount, minOutputAmount);
}
- _swap(inputToken, inputAmount, outputToken, outputAmount);
+ _swap(inputToken, inputAmount, outputToken, output);
}
Updates
Appeal created
inallhonesty about 1 year ago
Submission Judgement Published Assigned finding tags:
Default value returned by TSwapPool::swapExactInput results in incorrect return value given
Rewards breakdown
nSLOC
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100 EXP
20 EXP
2 EXP
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