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How does someone get to cast more than 40 votes in a day?

The daily vote limit appears to be subject to a race condition which could potentially defeat the limit. When I vote on a post, the system seems to count the vote against the post score before it counts against my vote limit, rather than acting as an atomic transaction, and this appears to be exploitable under a high-latency Internet connection (the network I was working from at the time randomly stalls for several seconds waiting for a response, possibly due to faulty on-site routing).

This is manifested as a substantial delay in getting the "you have x votes left today" warning: If I quickly cast more than x votes before this warning is displayed again, I can exceed the daily vote limit—a time-of-check-to-time-of-use bug. The result is the following (although I immediately retracted the extra vote):

41 votes in a day caused by non-atomic vote scoring

Can someone look into this?

Edit: Upon casting the final vote before the clock rolled over, I got "Daily vote limit reached; vote again in 36 seconds." I apparently got confused over the message, but there did seem to be some sort of anomaly with the way votes were being counted, as if the post score update and daily vote count update were not an atomic operation...

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    Interesting find. I never really understood the point of having limits on voting. Seems counter productive.
    – chown
    Commented Sep 25, 2012 at 1:13
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    During the very early days of the site, there weren't any limits, @chown. Folks... Had fun with that. One particularly blatant example involved a script that up-voted everything. Post something, get an up-vote. Talk about rep inflation...
    – Shog9
    Commented Sep 25, 2012 at 1:38
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    @Shog9 Are you talking about this? stackoverflow.com/questions/21064/massive-reputation-jump
    – Mysticial
    Commented Sep 25, 2012 at 1:50
  • That's the one, @Mysticial - good find!
    – Shog9
    Commented Sep 25, 2012 at 1:52
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    @Mysticial: That post is deleted.
    – Mechanical snail
    Commented Sep 25, 2012 at 2:10
  • @Mechanicalsnail: yes, it dates back to the Stack Overflow private beta - it's been deleted for a very long time now.
    – Shog9
    Commented Sep 25, 2012 at 2:11
  • @Shog9 Shouldn't it be migrated to meta rather than deleted then?
    – Mechanical snail
    Commented Sep 25, 2012 at 2:14
  • If true, then you're saying the limitation is client side? That can't be true, as then it would easily be abused on any internet connection.
    – Arjan
    Commented Sep 25, 2012 at 2:15
  • @Mechanicalsnail: it was deleted by its author, long long before Meta existed.
    – Shog9
    Commented Sep 25, 2012 at 2:16
  • Deleting my answer in response to your edit, however: so far as I can tell, you were never over the voting limit; I've gotta assume this is some sort of craziness involving voting right around the date rollover.
    – Shog9
    Commented Sep 25, 2012 at 3:38
  • @Shog9: I've got a feeling that the new review system was involved; if I vote on a post and advance to the next item too quickly, it might not have recorded the vote count correctly, causing erroneous messages. The system had apparently claimed that I had more votes left than I thought I had, and this appears to have been triggered by the networking issues I mentioned. I'm not sure precisely what went wrong, though, and it could be little more than a simple UI bug...
    – bwDraco
    Commented Sep 25, 2012 at 3:46
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    By the time you advance in the review queue, your vote should've already been recorded or at very least submitted. Not saying there can't be some UI weirdness there, but it should be as safe as any other way of voting. BTW: it looks like Mechanical snail got the right answer for why 41 votes showed up on your user drop-down.
    – Shog9
    Commented Sep 25, 2012 at 4:18
  • big deal. I once had dozen of "race conditions" like this
    – gnat
    Commented Sep 25, 2012 at 8:19

1 Answer 1

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Another possibility is that it's the same phenomenon as How does someone get to cast more than 40 votes in a day?. That is, one of your votes was on a subsequently-deleted post.

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    This appears to have been the case after all - one of the first answers he voted on yesterday was deleted shortly afterwards.
    – Shog9
    Commented Sep 25, 2012 at 4:17
  • I have decided to cast the first vote to close. (Users with at least 250 reputation can view close votes and vote to close on their own questions.)
    – bwDraco
    Commented Sep 25, 2012 at 14:55

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