1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Hey Guest, is it this your first time on the forums?

    Visit the Beginner's Box

    Introduce yourself, read some of the ins and outs of the community, access to useful links and information.

    Dismiss Notice

Server random crash

Discussion in 'Archive' started by TheWhiteLights, May 24, 2014.

  1. TheWhiteLights

    TheWhiteLights Shipwright

    Messages:
    5
    Category: KAG Server
    Operating system: Linux : Ubuntu 14.04 LTS (Trusty Tahr)
    Build number: 1120
    Description: I woke up this morning to check on my server and it was not running.
    Steps to reproduce: Unknown/Random. Never happened before and I was not playing at the time. Screenshots/Videos: kagerror.jpg
     
  2. Leo

    Leo Haxor

    Messages:
    503
    Happened to my CTF today too, just this error. Never saw that before. Also Ubuntu 14.04
    *WOW, this Mr_J guy joined to my server too before the crash. Just to be sure I banned him from all my servers.
     
    Last edited: May 24, 2014
  3. bunnie

    bunnie Haxor Tester

    Messages:
    1,319
    he had bad luck or is a good hacker, there aren't much good hackers in kag...
    Very interesting... Not sure, but i think that shadlington will know something... @Shadlington
     
  4. Leo

    Leo Haxor

    Messages:
    503
    My EU CTF:
    [16:48:35] * Mr_J connected (admin: 0 guard 0 gold 1 tester 0)
    [16:48:35] Closing console device: Signal 6 received

    My US CTF:
    [09:49:30] * Mr_J connected (admin: 0 guard 0 gold 1 tester 0)
    [09:49:31] Closing console device: Signal 6 received

    No bad luck, something fishy here.
     
    zerd, RadioActive and UnnamedPlayer like this.
  5. jrgp

    jrgp THD Team THD Team Administrator Global Moderator

    Messages:
    75
    A good first start is not running your game server as root. If the KAG server gets hacked your entire box can get fucked. Is creating an extra user really that hard?

    Additionally, KAG crashes randomly anyway. Just use a shell script to restart it when it fails.
     
    Frederikam and Furai like this.
  6. Furai

    Furai THD Team THD Team Administrator

    Messages:
    3,124
  7. Leo

    Leo Haxor

    Messages:
    503
    This is not "random", it's a guy that doing something and crashing the servers. This is not really the answer I was looking for.
     
  8. Geti

    Geti Please avoid PMing me (poke a mod instead) THD Team Administrator Global Moderator

    Messages:
    3,730
    Seems like it was directed at the OP, and the advice in it is good.


    As Furai says, it would be good if you could run them under gdb and get a backtrace upon this crash happening so we can see where it's actually crashing and fix the issue. Seeing a name in a log and then your server crashing with a memory address dump is not enough information to even start debugging the issue. If the same user keeps doing this to servers we can ban him, but we need someone to be doing it to be able to catch and fix the vulnerability.
     
  9. TheWhiteLights

    TheWhiteLights Shipwright

    Messages:
    5
    I created a user account just for you~ ^^

    I'll try this out. Thanks :)
     
    Geti likes this.
  10. MM

    MM THD Team THD Team Administrator Global Moderator

    Messages:
    327
    Do you have debug mode on?
     
  11. jrgp

    jrgp THD Team THD Team Administrator Global Moderator

    Messages:
    75
    Is this issue still prevalent? Did you run kagdedi under gdb and get a stacktrace?

    Nice attitude.
     
    Mazey likes this.
  12. Geti

    Geti Please avoid PMing me (poke a mod instead) THD Team Administrator Global Moderator

    Messages:
    3,730
    There's a guy called C4Bios doing this on Aus servers as well - it could be that some weird install setup makes this happen on join, and the guy has no idea that he's crashing servers, or it could be an exploit. It would be really good to have a proper backtrace on where it's happening though - its clear that it's either a double or invalid free() call but not where it's being called or what it's being called on.
    If you could do that (run in gdb, when it crashes type "bt full" and send output) that'd be great.
     
  13. Leo

    Leo Haxor

    Messages:
    503
    Personally I just banned this guy from my servers. I don't like making experiments on working servers. You should find this guy and ask him.
     
  14. Geti

    Geti Please avoid PMing me (poke a mod instead) THD Team Administrator Global Moderator

    Messages:
    3,730
    We've tried, he hasn't responded. It's not an "experiement", it just lets us get full info when the game crashes - applies to more crashes than just this one.