Steps to reproduce:
0. [IMPORTANT] Make sure you will be able to reconfigure your system
when all setuid binaries stop working (this includes sudo, which
makes this, IMHO, a serious bug).
Namely, either make sure you can log in as root, or keep a "sudo -s"
shell open. The latter is slightly more dangerous in the event of a
power outage.
I would also recommend running "guix pull" in this recovery shell, as
a root login shell will use root's profile, and not your own.
1. Add a non-existant file to your system configuration's
setuid-programs. For example,
(setuid-programs (cons*
#~(string-append #$bash "/bin/enoent")
%setuid-programs))
2. Reconfigure your system.
$ sudo guix system reconfigure /etc/config.scm
Actual behavior:
activating system...
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
building
/gnu/store/0ay9wd3wz4x0f5mgmbdfs72w98qvm68z-switch-to-system.scm.drv...
making '/gnu/store/7vwa2xd378fgwrkgwif7pi6ymshsf2jc-system' the current
system...
setting up setuid programs in '/run/setuid-programs'...
guix system: error: copy-file: No such file or directory:
"/run/setuid-programs/enoent"
$ sudoedit /etc/config.scm
-bash: /run/setuid-programs/sudoedit: No such file or directory
$ ls -l /run/setuid-programs
total 0
Expected behavior: the running system is left untouched.
/run/setuid-programs is still populated with the previous generation's
setuid programs. The error message says that the source of the copy-file
doesn't exist, not the destination. (While the latter is technically
correct, it's utterly unhelpful)
3. [OPTIONAL] Run a rollback.
# guix system roll-back
Expected behavior: /run/setuid-programs gets populated again.
Actual behavior: /run/setuid-programs is still empty.
(Is this a separate bug with roll-back not restoring setuid-programs? No
idea, didn't test)
4. Remove the changes made to the configuration and run reconfigure
again.
# guix system reconfigure /etc/config.scm
Expected & actual behavior: system is back in (AFAIK) a well-defined
state.
Regards,
Jakub Kądziołka
