[tor-bugs] #12229 [Tor]: Sandbox: bad syscall attempt (syscall getrlimit) after "New control connection opened"

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#12229: Sandbox: bad syscall attempt (syscall getrlimit) after "New control
connection opened"
-----------------------+------------------------------------
 Reporter:  alphawolf  |          Owner:
     Type:  defect     |         Status:  new
 Priority:  normal     |      Milestone:  Tor: 0.2.5.x-final
Component:  Tor        |        Version:  Tor: 0.2.5.4-alpha
 Keywords:  sandbox    |  Actual Points:
Parent ID:             |         Points:
-----------------------+------------------------------------
 Tor crashes with stack trace when sandbox enabled and controller (arm)
 connects.  This is a regression at some point between
 `c21377e7bcc70d2a456409225d8b2d91990a14cd` (good) and
 `a6688f9cbb930ad139a7f3886684fcadeec59d30` (bad).  I haven't had a chance
 to bisect yet.  If someone has an educated guess which commit might be at
 fault, that will save me a lot of time :)

 Tor 0.2.5.4-alpha-dev (git-95d47a74815ede0e)
 Debian Jessie, kernel 3.14-1-amd64
 libseccomp-dev 2.1.1-1

 To repro:
 * Enable sandbox, start tor.
 * Open arm
 * Observe that tor has crashed.


 log:
 {{{
 Jun 08 02:04:20.000 [notice] New control connection opened.

 ============================================================ T= 1402207460
 (Sandbox) Caught a bad syscall attempt (syscall getrlimit)
 /usr/bin/tor(+0x123afa)[0x7f11e2773afa]
 /lib/x86_64-linux-gnu/libc.so.6(getrlimit64+0x7)[0x7f11e0d771e7]
 /lib/x86_64-linux-gnu/libc.so.6(getrlimit64+0x7)[0x7f11e0d771e7]
 /usr/bin/tor(set_max_file_descriptors+0x2e)[0x7f11e276144e]
 /usr/bin/tor(+0xd75d6)[0x7f11e27275d6]
 /usr/bin/tor(+0x31ed0)[0x7f11e2681ed0]
 /usr/bin/tor(connection_control_process_inbuf+0x1b44)[0x7f11e272d634]
 /usr/bin/tor(+0xc8b55)[0x7f11e2718b55]
 /usr/bin/tor(+0x34af1)[0x7f11e2684af1]
 /usr/lib/x86_64-linux-
 gnu/libevent-2.0.so.5(event_base_loop+0x414)[0x7f11e1cdc184]
 /usr/bin/tor(do_main_loop+0x195)[0x7f11e2686285]
 /usr/bin/tor(tor_main+0x18d5)[0x7f11e2689245]
 /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7f11e0cbab45]
 /usr/bin/tor(+0x32adb)[0x7f11e2682adb]
 }}}

 /usr/share/tor/tor-service-defaults-torrc:
 {{{
 DataDirectory /var/lib/tor
 PidFile /var/run/tor/tor.pid
 RunAsDaemon 1
 User debian-tor
 ControlSocket /var/run/tor/control
 ControlSocketsGroupWritable 1
 CookieAuthentication 1
 CookieAuthFileGroupReadable 1
 CookieAuthFile /var/run/tor/control.authcookie
 Log notice file /var/log/tor/log
 }}}

 torrc:
 {{{
 ORPort 9001
 Sandbox 1
 }}}

 (I see getrlimit mentioned in the comments of #9894, not sure if same
 bug.)

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/12229>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
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