Bug#932384: libc6: utmp broken
Aurelien Jarno dixit: [ explanations ] >Therefore there is no bug, neither in glibc nor in the manpage. Closing >it. Agreed. Thank you for reviewing the problem, though. bye, //mirabilos -- 15:41⎜ Somebody write a testsuite for helloworld :-)
Bug#932384: libc6: utmp broken
On Thu, 18 Jul 2019, Thorsten Glaser wrote: > glibc maintainers: unsure why screen works but not the example > code given that screen isn’t sgid… maybe you should have a look > at that, it still doesn’t work with the correct utmp permissions. This might also be a bug in the example program; if so, reassign to manpages-dev (= 5.01-1), cf. #932382 bye, //mirabilos -- tarent solutions GmbH Rochusstraße 2-4, D-53123 Bonn • http://www.tarent.de/ Tel: +49 228 54881-393 • Fax: +49 228 54881-235 HRB 5168 (AG Bonn) • USt-ID (VAT): DE122264941 Geschäftsführer: Dr. Stefan Barth, Kai Ebenrett, Boris Esser, Alexander Steeg ** Mit der tarent Academy bieten wir auch Trainings und Schulungen in den Bereichen Softwareentwicklung, Agiles Arbeiten und Zukunftstechnologien an. Besuchen Sie uns auf www.tarent.de/academy. Wir freuen uns auf Ihren Kontakt. **
Processed: Re: Bug#932384: libc6: utmp broken
Processing commands for cont...@bugs.debian.org: > reassign 932380 initscripts Bug #932380 [screen] screen: Utmp slot not found -> not removed Bug reassigned from package 'screen' to 'initscripts'. No longer marked as found in versions screen/4.6.2-3. Ignoring request to alter fixed versions of bug #932380 to the same values previously set > found 932380 2.95-1 Bug #932380 [initscripts] screen: Utmp slot not found -> not removed Marked as found in versions sysvinit/2.95-1. > notfound 932380 2.93-8 Bug #932380 [initscripts] screen: Utmp slot not found -> not removed Ignoring request to alter found versions of bug #932380 to the same values previously set > retitle 932380 initscripts: /etc/init.d/bootmisc.sh: wrong /var/run/utmp > permissions Bug #932380 [initscripts] screen: Utmp slot not found -> not removed Changed Bug title to 'initscripts: /etc/init.d/bootmisc.sh: wrong /var/run/utmp permissions' from 'screen: Utmp slot not found -> not removed'. > severity 932380 important Bug #932380 [initscripts] initscripts: /etc/init.d/bootmisc.sh: wrong /var/run/utmp permissions Severity set to 'important' from 'normal' > unblock 932380 by 932384 Bug #932380 [initscripts] initscripts: /etc/init.d/bootmisc.sh: wrong /var/run/utmp permissions 932380 was blocked by: 932384 932380 was not blocking any bugs. Removed blocking bug(s) of 932380: 932384 > block 932384 by 932380 Bug #932384 [libc6] libc6: utmp broken 932384 was not blocked by any bugs. 932384 was not blocking any bugs. Added blocking bug(s) of 932384: 932380 > thanks Stopping processing here. Please contact me if you need assistance. -- 932380: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=932380 932384: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=932384 Debian Bug Tracking System Contact ow...@bugs.debian.org with problems
Re: Bug#932384: libc6: utmp broken
reassign 932380 initscripts
found 932380 2.95-1
notfound 932380 2.93-8
retitle 932380 initscripts: /etc/init.d/bootmisc.sh: wrong /var/run/utmp
permissions
severity 932380 important
unblock 932380 by 932384
block 932384 by 932380
thanks
On Thu, 18 Jul 2019, Thorsten Glaser wrote:
> After hitting #932380
I’ve had a look at what was recently updated, found initscripts
as something that matches a recursive grep for utmp in /etc, and
sure, the diff between 2.93-8 and 2.95-1 in etc/init.d/bootmisc.sh
contains this:
- chmod 664 /var/run/utmp
+ chmod 644 "${utmp}" || log_warning_msg "failed to chmod
${utmp}"
So there we are.
Dmitry: please also move the chmod BELOW the chown, as chown
is known to sometimes reset permissions (in some documented
cases, not a bug):
tglase@tglase:~ $ diff -u /etc/init.d/bootmisc.sh bootmisc.sh
--- /etc/init.d/bootmisc.sh 2019-05-15 13:03:46.0 +0200
+++ bootmisc.sh 2019-07-18 17:51:51.887830376 +0200
@@ -33,8 +33,8 @@
readonly utmp='/var/run/utmp'
if > "${utmp}" ; then
- chmod 644 "${utmp}" || log_warning_msg "failed to chmod
${utmp}"
chgrp utmp "${utmp}" || log_warning_msg "failed to chgrp
${utmp}"
+ chmod 664 "${utmp}" || log_warning_msg "failed to chmod
${utmp}"
return 0
else
log_failure_msg "failed to truncate ${utmp}"
XTaran: after “sudo chmod 664 /var/run/utmp” GNU screen works as
intended again, closing your bug.
glibc maintainers: unsure why screen works but not the example
code given that screen isn’t sgid… maybe you should have a look
at that, it still doesn’t work with the correct utmp permissions.
bye,
//mirabilos
--
tarent solutions GmbH
Rochusstraße 2-4, D-53123 Bonn • http://www.tarent.de/
Tel: +49 228 54881-393 • Fax: +49 228 54881-235
HRB 5168 (AG Bonn) • USt-ID (VAT): DE122264941
Geschäftsführer: Dr. Stefan Barth, Kai Ebenrett, Boris Esser, Alexander Steeg
**
Mit der tarent Academy bieten wir auch Trainings und Schulungen in den
Bereichen Softwareentwicklung, Agiles Arbeiten und Zukunftstechnologien an.
Besuchen Sie uns auf www.tarent.de/academy. Wir freuen uns auf Ihren Kontakt.
**
Re: Bug#932384: libc6: utmp broken
On Thu, 18 Jul 2019, Thorsten Glaser wrote: > utmp entries cannot be added (and the GNU screen source code contains > curse^Wcomplaints about the GNU API for utmp lacking the ability to > return success/error information, so the applications cannot even de‐ > tect this!), while the file is set up correctly: After some more experimentation: • this affects buster(!) • it works as root but not as regular user bye, //mirabilos -- tarent solutions GmbH Rochusstraße 2-4, D-53123 Bonn • http://www.tarent.de/ Tel: +49 228 54881-393 • Fax: +49 228 54881-235 HRB 5168 (AG Bonn) • USt-ID (VAT): DE122264941 Geschäftsführer: Dr. Stefan Barth, Kai Ebenrett, Boris Esser, Alexander Steeg ** Mit der tarent Academy bieten wir auch Trainings und Schulungen in den Bereichen Softwareentwicklung, Agiles Arbeiten und Zukunftstechnologien an. Besuchen Sie uns auf www.tarent.de/academy. Wir freuen uns auf Ihren Kontakt. **
Bug#932384: libc6: utmp broken
Package: libc6 Version: 2.28-10 Severity: important After hitting #932380 I looked at the source code of GNU screen, saw it uses the getutline(3) function, and compiled the example from its manpage. The output is not what I expected: tglase@tglase:~ $ ./a.out before adding entry: tglase :0 2019-07-18 16:07 after adding entry: tglase :0 2019-07-18 16:07 after removing entry: tglase :0 2019-07-18 16:07 This is the same, no matter whether I’m in GNU screen in xterm, or just in xterm, or even on the Linux text console: tglase@tglase:~ $ ./a.out before adding entry: tglase tty2 2019-07-18 17:25 tglase :0 2019-07-18 16:07 after adding entry: tglase tty2 2019-07-18 17:25 tglase :0 2019-07-18 16:07 after removing entry: tglase tty2 2019-07-18 17:25 tglase :0 2019-07-18 16:07 utmp entries cannot be added (and the GNU screen source code contains curse^Wcomplaints about the GNU API for utmp lacking the ability to return success/error information, so the applications cannot even de‐ tect this!), while the file is set up correctly: tglase@tglase:~ $ ll /var/run/utmp -rw-r--r-- 1 root utmp 4608 Jul 18 17:26 /var/run/utmp tglase@tglase:~ $ w | cat 17:27:33 up 1:21, 1 user, load average: 1.35, 1.68, 2.12 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT tglase :0 -16:07 ?xdm? 14:24 0.03s /usr/bin/ck-launch-session /usr/bin/monkeysphere-validation-agent /bin/mksh /usr/share/tarent/autokde.d/loadenv.sh icewm-session -- System Information: Debian Release: bullseye/sid APT prefers unreleased APT policy: (500, 'unreleased'), (500, 'buildd-unstable'), (500, 'unstable'), (100, 'experimental') Architecture: x32 (x86_64) Foreign Architectures: i386, amd64 Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores) Kernel taint flags: TAINT_FIRMWARE_WORKAROUND Locale: LANG=C, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=C (charmap=UTF-8) Shell: /bin/sh linked to /bin/lksh Init: sysvinit (via /sbin/init)
