Forgottenserver: Teleport loop -> crash

[BahamutxD]

Steps to reproduce

Create 2 teleports. Teleport A takes you to pos of teleport B. Teleport B takes you to pos of teleport A.

An alternative way is to create a teleport in X position that teleports you that same X posistion.

Entering the teleport will crash server.

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I know this is a rare case but due to how some servers work it may be possible to reproduce and exploit this issue.

The server should avoid crashing if conditions are met.

[MillhioreBT]

No ordinary player can reproduce this event, if you give someone the power to create portals make sure they are not a troll.
Including this to the sources to only prevent the troll from doing their evils is not reasonable, we are not supposed to hire trolls to administer our servers.

[DSpeichert]

It's obvious such thing would happen, so I'd say it works as designed.

[MillhioreBT]

@BahamutxD If you want to add it to your server: https://github.com/MillhioreBT/forgottenserver/commit/4f9cd6d6288fb05556db5682222f10e60921e2b6

Any loop situation avoids it.

[BahamutxD]

@BahamutxD If you want to add it to your server: MillhioreBT@4f9cd6d

Cheers, don't have a server myself but perhaps someone can find it useful

[DSpeichert]

@MillhioreBT if you feel like opening a PR with this fix, I think it's reasonable enough to merge it.

[Zbizu]

There are 73 occurences of infinite loop errors ("call stack overflow"). If this solution can prevent the server from crashing, it could be used more widely in sources.

[andersonfaaria]

@Zbizu the vast majority of call stack overflow cases can't really be identified nor fixed, it's what we call 'the halting problem' https://www.youtube.com/watch?v=macM_MtS_w4