Files that libguestfs creates have no SELinux label. On an enforcing
guest (RHEL, Rocky, Alma, Fedora) sshd may not read the unlabeled
/root/.ssh/authorized_keys, so a key added from the panel did not let
anyone log in ("avc: denied { read } ... unlabeled_t").
After writing a key, gstfsd now relabels /root/.ssh with the guest's own
file contexts (/etc/selinux/<SELINUXTYPE>/contexts/files/file_contexts),
as virt-customize does. Guests without an SELinux policy or with SELinux
disabled are left as they are. If the guest needs labels but the host's
libguestfs cannot set them, the request fails before anything is written.
A root password needs no labelling: /etc/shadow keeps its file and label.
gstfsd mounted every partition it listed: a root on LVM was never found,
a disk with two OS roots got the change twice and two concatenated
replies, and no root, an error or a request longer than 1024 bytes ended
the connection without a reply. It now lets libguestfs inspect the guest,
mounts its one OS the way the guest does (a broken filesystem off the
changed path is left out), and sends exactly one reply, keeping the first
error. The root entry is found on any line of /etc/shadow and must be
unique; a key needs no shadow file. A request is at most 64 KiB. Each
change runs in a worker process with a directly started appliance; both
are killed when the request is not done 100 s after gstfsd accepted it
(GSTFSD_DEADLINE may only lower that), before the panel's 120 s timeout
releases the VM, or when the panel's connection ends, and the reply waits
until they are gone, so nothing touches the disk once the panel has given
up. A worker that dies says why. The panel
connects over IPv4 or IPv6, sends the whole request and reads the reply
until gstfsd closes.
The web app (wsgi.py), novncd and socketiod set SIGCHLD to SIG_IGN at
import. The kernel then reaps every child at once, so subprocess loses
the exit status and a failing command reports 0, in the server and in
anything else run in that process: the test suite had to reset the
signal in two tests.
It was added in 2023 against one defunct bash per gunicorn worker and
per novncd. That bash came from the settings template of the time,
which ran .dec_ldap_pwd.sh with Popen and never waited for it; the
template stopped doing that in 561fedf. A settings.py still holding
that line leaves at most one zombie per process, not a growing number.
- wsgi.py, novncd, socketiod: the global SIG_IGN is removed. subprocess
reaps its own children, websockify installs its own SIGCHLD reaper
for novncd's connection processes, and novncd's SSH tunnels wait for
their ssh process.
- socketiod: the pty child execs consolecallback instead of running it
and then returning into the server's code; disconnect reaps that
child (waitpid) instead of any child (wait).
- The settings template drops its unused subprocess import; the two
test workarounds are removed.
New tests load the web app and novncd in a fresh interpreter and check
that SIGCHLD is untouched and a failing command still returns 1; both
fail on the previous code. A patched novncd in the test container
served five connections and left no child behind.
Comments, docstrings and live test names cited item IDs of a roadmap
that is not part of the repository. They now say what is meant, or
nothing where the sentence stands without them. Test assertions and
behavior are unchanged.
- Add the public key to authorized_keys instead of replacing the file.
- Use AF_INET6 when GSTFSD_BIND_HOST is an IPv6 address (binding ::1
crashed with the AF_INET server).
- Close idle client connections after 30 s.
Tests run the real daemon against a small fake guestfs module over a
socket; this also exercises the earlier sendall() fix.
- Hash the root password with a random SHA-512 salt instead of the fixed
"$6$kgPoiREy".
- Talk to gstfsd through one helper with a 120 s socket timeout; an
unreachable daemon or a bad reply is an error message, not a 500.
- gstfsd refuses to listen on a non-loopback address unless
GSTFSD_ALLOW_REMOTE=1: it is an unauthenticated root service.
- gstfsd: encode replies (sendall(str) raised TypeError on Python 3, so
the success path never worked) and use octal chmod modes.
- README: what gstfsd does and how to allow it on a remote compute.
