[tor-bugs] #31898 [Core Tor/Tor]: Occasional crash during shutdown when using Tor API

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#31898: Occasional crash during shutdown when using Tor API
-------------------------------------------------+-------------------------
 Reporter:  sysrqb                               |          Owner:  nickm
     Type:  defect                               |         Status:
                                                 |  accepted
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.4.2.x-final
Component:  Core Tor/Tor                         |        Version:  Tor:
                                                 |  0.4.2.1-alpha
 Severity:  Normal                               |     Resolution:
 Keywords:  042-regression, crash, 042-must      |  Actual Points:
  041-backport? 041-regression?                  |
Parent ID:                                       |         Points:  1
 Reviewer:                                       |        Sponsor:
                                                 |  Sponsor31-must
-------------------------------------------------+-------------------------

Comment (by sysrqb):

 Replying to [comment:4 nickm]:
 > A smaller test case might help here, or maybe a link to the RunMain
 source.

 I rebased the branch I used for testing the API on top of current master.
 The configuration is handled
 [https://gitweb.torproject.org/user/sysrqb/tor.git/tree/src/tools/jverify_config.java?h=testing_26653_02#n16
 here] and
 [https://gitweb.torproject.org/user/sysrqb/tor.git/tree/src/feature/api/TorApi.c?h=testing_26653_02#n173
 RunMain] is there.

 This is basically a thin wrapper around the API.

 >
 > One thing to note is that the stack trace that you're describing seems
 to be happening inside the initialization code, before Tor is actually
 running.  Maybe this is something that happens on a second initialization
 and not a first?

 Yes, that is what this code is doing. On the Java-side, it takes in
 commandline args which are passed into tor for configuration, but it
 configures and runs tor twice. The first time the program inserts
 `--verify-config` as the second argument, and then after `tor_run_main`
 returns, it calls `tor_main_configuration_set_command_line` again except
 this time with the original args (without `--verify-config`) and then
 calls `tor_run_main` again.

 Is reusing a `tor_main_configuration_t` with different args a supported
 use case? I haven't looked at the code yet. I don't see this crash during
 every execution, I usually run the program in a `while` loop until it
 crashes (which usually takes between 5 and 30 iterations).

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/31898#comment:5>
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