[tor-relays] tor crash on HUP only when SANDBOX is 1

[tor-relay at riseup.net]

just a little update:

I've reproduced this bug on my laptop with Debian Buster.

I've noticed that this problem occurs only with tor 0.4.2.5.  Tor 
0.4.1.6, from Debian buster backports repository, works properly.


Il 05/01/20 07:43, tor-relay at riseup.net ha scritto:
> Hi,
>
> I'm running an exit relay on a Debian Buster. I installed libseccomp 
> and I've built tor 0.4.2.5 using debuild, like the wiki says.
>
> Today I noticed that tor crashes on HUP signal, only when the Sandbox 
> option is on. I never had this problem.
>
>
> This is what my log says:
>
> an 05 08:23:10.000 [notice] Received reload signal (hup). Reloading 
> config and resetting internal state.
> Jan 05 08:23:10.000 [notice] Read configuration file 
> "/usr/share/tor/tor-service-defaults-torrc".
> Jan 05 08:23:10.000 [notice] Read configuration file "/etc/tor/torrc".
> Jan 05 08:23:10.000 [notice] Tor 0.4.2.5 opening log file.
>
> ============================================================ T= 
> 1578205390
> (Sandbox) Caught a bad syscall attempt (syscall dup)
> /usr/bin/tor(+0x1fc9fa)[0x561d896b29fa]
> /lib/x86_64-linux-gnu/libc.so.6(dup+0x7)[0x7f0bebf4bbc7]
> /lib/x86_64-linux-gnu/libc.so.6(dup+0x7)[0x7f0bebf4bbc7]
> /usr/bin/tor(tor_log_update_sigsafe_err_fds+0x18b)[0x561d896c699b]
> /usr/bin/tor(set_options+0x3c0)[0x561d89642f80]
> /usr/bin/tor(options_init_from_string+0x17d)[0x561d896453dd]
> /usr/bin/tor(options_init_from_torrc+0x404)[0x561d89645a74]
> /usr/bin/tor(+0x5f961)[0x561d89515961]
> /usr/lib/x86_64-linux-gnu/libevent-2.1.so.6(+0x22a6c)[0x7f0bec5a3a6c]
> /usr/lib/x86_64-linux-gnu/libevent-2.1.so.6(event_base_loop+0x5a7)[0x7f0bec5a4537] 
>
> /usr/bin/tor(do_main_loop+0xff)[0x561d8952a3af]
> /usr/bin/tor(tor_run_main+0x1105)[0x561d89517d55]
> /usr/bin/tor(tor_main+0x3a)[0x561d8951523a]
> /usr/bin/tor(main+0x19)[0x561d89514df9]
> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7f0bebe8509b]
> /usr/bin/tor(_start+0x2a)[0x561d89514e4a]
>
> I'm telling you because i think it could be a bug, but I'm not sure 
> that It's not caused by something else.
>
> At the moment I've disabled Sandbox. Please, let me know if I can fix 
> this in some way, thanks.
>