[tor-bugs] #29607 [Core Tor/Tor]: Denial of service on v2 onion service

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#29607: Denial of service on v2 onion service
--------------------------+--------------------------
 Reporter:  pidgin        |          Owner:  pidgin
     Type:  defect        |         Status:  accepted
 Priority:  Immediate     |      Milestone:
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:  #25461        |         Points:
 Reviewer:                |        Sponsor:
--------------------------+--------------------------

Comment (by pidgin):

 Replying to [comment:16 asn]:
 > We might need a log file (preferably info/debug level) to get deeper
 into this. Please make sure you don't reveal any sensitive info (e.g.
 guard names) through the log file.
 >
 > Otherwise, do you see any warn logs, or any weird stuff on the
 info/debug severity that you can point out?

 here is the log from the onion v3 service, a debug/info log follows soon :


 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:47.000 [warn] No valid circuit build time data out of 1000
 times, 3 modes, have_timeout=1, 2332.000000ms
 -scrubbed-:42:48.000 [warn] circuit_build_times_update_alpha(): Bug: Could
 not determine largest build time (0). Xm is 3125ms and we've abandoned 999
 out of 1000 circuits. (on Tor 0.4.0.1-alpha 81f1b89efc94723f)
 -scrubbed-:42:48.000 [warn] circuit_build_times_update_alpha(): Bug: Could
 not determine largest build time (0). Xm is 3125ms and we've abandoned 998
 out of 1000 circuits. (on Tor 0.4.0.1-alpha 81f1b89efc94723f)
 -scrubbed-:42:50.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:42:50.000 [warn] Giving up on launching a rendezvous circuit to
 [scrubbed] for hidden service [scrubbed]
 -scrubbed-:42:52.000 [notice] Your network connection speed appears to
 have changed. Resetting timeout to 60s after 18 timeouts and 1000
 buildtimes.
 -scrubbed-:45:30.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:45:30.000 [warn] Giving up on launching a rendezvous circuit to
 [scrubbed] for hidden service [scrubbed]
 -scrubbed-:46:40.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:46:40.000 [warn] Giving up on launching a rendezvous circuit to
 [scrubbed] for hidden service [scrubbed]
 -scrubbed-:47:25.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:47:25.000 [warn] Giving up on launching a rendezvous circuit to
 [scrubbed] for hidden service [scrubbed]
 -scrubbed-:47:27.000 [notice] Your network connection speed appears to
 have changed. Resetting timeout to 60s after 18 timeouts and 131
 buildtimes.
 -scrubbed-:47:27.000 [notice] Your network connection speed appears to
 have changed. Resetting timeout to 120s after 18 timeouts and 0
 buildtimes.
 -scrubbed-:48:47.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:48:47.000 [warn] Failed to launch rendezvous circuit to
 [scrubbed]
 -scrubbed-:50:34.000 [warn] Failed to find node for hop #1 of our path.
 Discarding this circuit.
 -scrubbed-:50:34.000 [warn] Giving up on launching a rendezvous circuit to
 [scrubbed] for hidden service [scrubbed]






 a debug/info log follows soon

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/29607#comment:17>
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