race condition between claimReward() and opening a channel again?

[pirapira]

claimReward() works only when the TokenNetwork contract has no ChannelState between the two participants.

raiden-contracts/raiden_contracts/contracts/services/MonitoringService.sol

Line 258 in c6e9454

require(channel_state == 0);

So if I don't want to pay a MS, I can call TokenNetwork openChannel(me, partner, something) before the MS calls claimReward(). Then claimReward() will see Openned, and the MS won't get the reward. Is this correct?

[loredanacirstea]

This is because the MS contract is outdated. This PR #360 should fix the issue, as it also references the channel_identifier. This makes the distinction between the old and new channel:

        TokenNetwork.ChannelState channel_state;
        (, channel_state) = token_network.getChannelInfo(
            channel_identifier,
            closing_participant,
            non_closing_participant
        );

[pirapira]

I see, and I agree.