[Hurd] glibc lacks 'pt_chown' setuid program

  • Open
  • quality assurance status badge
Details
One participant
  • Ludovic Courtès
Owner
unassigned
Submitted by
Ludovic Courtès
Severity
normal
L
L
Ludovic Courtès wrote on 26 Nov 2022 19:22
Texinfo 6.7 test hangs on i586-gnu (GNU/Hurd)
(address . bug-guix@gnu.org)
87fse560e4.fsf@inria.fr
The ‘t/malformed-split.sh’ test of Texinfo 6.7 hangs on GNU/Hurd (in a
childhurd) as of commit 78f03567f44f704dfbc03cb64368aa42a01e78ad.

The test invokes its ‘pseudotty’ program, which creates a
pseudo-terminal using ‘posix openpt’. That call fails when not running
as root in a childhurd:

Toggle snippet (19 lines)
task109(pid14826)-> 4205 (227424 0 0);
75<--117(pid14826)->io_write_request ("./pseudotty: " -1)./pseudotty: = 0 13
75<--117(pid14826)->io_write_request ("getting pty master fd" -1)getting pty master fd = 0 21
75<--117(pid14826)->io_write_request ("\n" -1)
= 0 1
task109(pid14826)-> 4205 (227424 0 0);
task109(pid14826)-> 4205 (227424 0 0);
86<--120(pid14826)->dir_lookup ("dev/ptyp0" 3 0) = 0x4000000d (Permission denied)
86<--120(pid14826)->dir_lookup ("dev/ptyp1" 3 0) = 0x40000010 (Device or resource busy)
86<--120(pid14826)->dir_lookup ("dev/ptyp2" 3 0) = 0x4000000d (Permission denied)
86<--120(pid14826)->dir_lookup ("dev/ptyp3" 3 0) = 0x40000002 (No such file or directory)
task109(pid14826)-> 4205 (227424 0 0);
task109(pid14826)-> 4205 (227424 0 0);
118<--122(pid14826)->proc_mark_exit_request (256 0) = 0
task109(pid14826)-> 4205 (227424 0 0);
task109(pid14826)-> 2008 () = 0
Child 14826 exited with 1

The childhurd only has this:

Toggle snippet (6 lines)
ludo@childhurd /tmp/guix-build-texinfo-6.7.drv-0/texinfo-6.7/info$ ls -l /dev/ptyp*
crw--w---- 1 root tty 0, 0 Nov 26 16:05 /dev/ptyp0
crw--w---- 1 ludo tty 0, 0 Nov 26 16:05 /dev/ptyp1
crw------- 1 root root 0, 0 Nov 26 16:05 /dev/ptyp2

Ludo’.
L
L
Ludovic Courtès wrote on 27 Nov 2022 23:34
(address . 59616@debbugs.gnu.org)
875yf058nm.fsf@gnu.org
Hi,

Ludovic Courtès <ludo@gnu.org> skribis:

Toggle quote (7 lines)
> The childhurd only has this:
>
> ludo@childhurd /tmp/guix-build-texinfo-6.7.drv-0/texinfo-6.7/info$ ls -l /dev/ptyp*
> crw--w---- 1 root tty 0, 0 Nov 26 16:05 /dev/ptyp0
> crw--w---- 1 ludo tty 0, 0 Nov 26 16:05 /dev/ptyp1
> crw------- 1 root root 0, 0 Nov 26 16:05 /dev/ptyp2

Part of the solution is to create more of them in hurd-boot.scm.

But there’s a second problem: we need to build glibc’s ‘pt_chown’ setuid
program (with ‘--enable-pt_chown’) so that ‘grantpt’ can change the
owner of /dev/ttyp*.

At least that’s how it’s done on Debian GNU/Hurd, but I’m surprised
/hurd/term (for pty-slave) doesn’t just return the right UID on
‘io_stat’.

Ludo’.
L
L
Ludovic Courtès wrote on 30 Nov 2022 10:10
control message for bug #59616
(address . control@debbugs.gnu.org)
87sfi03j08.fsf@gnu.org
retitle 59616 [Hurd] glibc lacks 'pt_chown' setuid program
quit
?