[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_revision
 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:
-------------------------------------------------+-------------------------
Changes (by teor):

 * status:  needs_review => needs_revision


Comment:

 Replying to [comment:9 cyberpunks]:
 > Replying to [comment:3 teor]:
 > > So I don't think this is security-low, just slightly inefficient.
 >
 > It creates a temporary `Vec` containing up to 4 billion integers,
 actually, in order to call `.retain()` on it. The updated tests try to use
 massive amounts of RAM without this change.

 Ah, thanks! That was the information I needed to know.

 If this change fixes (enough) rust inefficiencies, we should be able to
 re-enable this test as well:
 https://github.com/torproject/tor/blob/991bec67ee41fd7f3c12e9194d96491b51bedd50/src/test/test_protover.c#L327

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/27206#comment:10>
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