[tor-bugs] #30658 [Core Tor/Torsocks]: Unsupported syscalls (292/dup3, 293/pipe2, 332/statx)

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#30658: Unsupported syscalls (292/dup3, 293/pipe2, 332/statx)
------------------------+-----------------------------------
 Reporter:  eirizuhaex  |          Owner:  dgoulet
     Type:  defect      |         Status:  new
 Priority:  Medium      |      Component:  Core Tor/Torsocks
  Version:              |       Severity:  Normal
 Keywords:              |  Actual Points:
Parent ID:              |         Points:
 Reviewer:              |        Sponsor:
------------------------+-----------------------------------
 I've been playing around with an torified environment via `. torsocks on`.
 Running a vanilla vim, torsocks complains about the mentioned syscalls:

 {{{#!sh
 $ vim -u NONE
 1559028872 WARNING torsocks[6802]: [syscall] Unsupported syscall number
 293. Denying the call (in tsocks_syscall() at syscall.c:568)
 1559028872 WARNING torsocks[6802]: [syscall] Unsupported syscall number
 332. Denying the call (in tsocks_syscall() at syscall.c:568)
 1559028873 WARNING torsocks[6802]: [syscall] Unsupported syscall number
 292. Denying the call (in tsocks_syscall() at syscall.c:568)
 }}}

 Peeking in the linux kernel source tree, these naively look safe to me:

 {{{#!sh
 $ egrep '^(293|332|292)' arch/x86/entry/syscalls/syscall_64.tbl
 292     common  dup3                    __x64_sys_dup3
 293     common  pipe2                   __x64_sys_pipe2
 332     common  statx                   __x64_sys_statx
 }}}

 Does adding these to the whitelist seem reasonable?

 === Version Info

 {{{#!sh
 $ torsocks --version
 Torsocks 2.3.0

 $ lsb_release --all
 LSB Version:    1.0
 Distributor ID: VoidLinux
 Description:    Void Linux
 Release:        rolling
 Codename:       void

 $ uname -a
 Linux lang 5.0.17_1 #1 SMP PREEMPT Fri May 17 08:23:10 UTC 2019 x86_64
 GNU/Linux
 }}}

 === Notes

 This is my first ticket here, so if I've commited some ''faux pas'' please
 forgive me. Cheers!

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30658>
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