[tor-bugs] #27206 [Core Tor/Tor]: rust protover_all_supported() takes forever on some inputs

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#27206: rust protover_all_supported() takes forever on some inputs
-------------------------------------------------+-------------------------
 Reporter:  cyberpunks                           |          Owner:  (none)
     Type:  defect                               |         Status:
                                                 |  needs_review
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.3.5.x-final
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  rust, protover, 033-backport,        |  Actual Points:
  034-backport                                   |
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
-------------------------------------------------+-------------------------

Comment (by teor):

 Oh, I thought we fixed all these DoS bugs in #24031 and #25250.

 And we added a 2^16^ limit for protocol expansion before rejecting the
 descriptor, vote, or consensus:
 https://github.com/torproject/tor/blob/master/src/rust/protover/protover.rs#L29
 https://github.com/torproject/tor/blob/master/src/core/or/protover.c#L451

 So I don't think this is security-low, just slightly inefficient.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/27206#comment:3>
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