Fix Debian postinst hang in preseed late_command chroot (#68269)#69427
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dwoz wants to merge 1 commit into
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Fix Debian postinst hang in preseed late_command chroot (#68269)#69427dwoz wants to merge 1 commit into
dwoz wants to merge 1 commit into
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The salt-minion (and salt-api, salt-cloud, salt-master, salt-syndic) postinst scripts source /usr/share/debconf/confmodule in their configure branch but never tear down the debconf protocol before the auto-generated #DEBHELPER# section runs. confmodule sets up fd 3 as the debconf passthrough (exec 3>&1). Without a matching db_stop + exec 3>&- pair, fd 3 leaks into the debhelper-added deb-systemd-helper invocations. In a normal interactive apt-get install this is mostly invisible, but in a non-interactive Debian preseed late_command chroot (where the parent debconf frontend is not reachable) it produces "Bad file descriptor" errors and can hang the install entirely. Add the standard debconf teardown after the case block in all five salt-*.postinst scripts. Only run it on the configure branch, since that's the only path that sources confmodule. Regression test in tests/pytests/unit/pkg/ stubs confmodule and substitutes the #DEBHELPER# token with an fd-3-leak probe; the test exercises all five postinst scripts and confirms fd 3 is closed and db_stop is called before #DEBHELPER# runs. Fixes saltstack#68269
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What does this PR do?
The Debian salt-minion (and salt-api, salt-cloud, salt-master,
salt-syndic) postinst scripts source
/usr/share/debconf/confmodulein their configure branch but never tear down the debconf protocol
before the auto-generated
#DEBHELPER#section runs.confmoduleopens fd 3 as the debconf passthrough; without a matching
db_stopand
exec 3>&-, fd 3 leaks into the debhelper-addeddeb-systemd-helperinvocations. In non-interactive Debian preseedlate_commandchroots (no reachable parent debconf frontend) thatleak produces "Bad file descriptor" errors and can hang the install
entirely.
This PR adds the canonical debconf teardown (
db_stop+exec 3>&-) on the configure branch of all five salt-*.postinst scripts,and adds a regression test that stubs
confmoduleand replaces the#DEBHELPER#token with an fd-3 leak probe.What issues does this PR fix or reference?
Fixes #68269
Previous Behavior
apt-get install salt-minioninvoked from a Debian preseedlate_commandchroot hangs and reports/var/lib/dpkg/info/salt-minion.postinst: 66: 3: Bad file descriptor,breaking unattended Debian provisioning that installs the salt-minion
package.
New Behavior
The configure branch terminates the debconf protocol cleanly with
db_stopand explicitly closes fd 3 withexec 3>&-before thedebhelper-generated section runs.
deb-systemd-helperno longerinherits a stale fd 3, and the postinst completes whether or not the
parent debconf frontend is reachable.
Merge requirements satisfied?
Commits signed with GPG?
No (matches base branch tip)