fix(deploy-ha): stop-all.sh/cleanup.sh must also kill the real worker's sudo child (bug-1820)

start-worker.sh's real-worker branch writes the pidfile via `echo $$`
then `exec sudo "$WORKER_BIN" ...` -- exec replaces the pidfile-writing
shell with sudo in place (same PID), so the pidfile records sudo's own
PID, not the actual xcecd daemon's. sudo forks a separate, root-owned
child to run the real worker; kill -9 on sudo's PID kills only sudo
(SIGKILL can't be forwarded to a child), silently orphaning xcecd. The
existing "still alive after kill -9" warning never caught this either,
since it re-checked the same (already-dead) sudo PID.

Both generated stop-all.sh and cleanup.sh now detect a sudo-wrapped
pidfile entry (its /proc/$PID/cmdline starts with "sudo "), find its
child via pgrep -P, and kill that child with sudo first. The
still-alive check now also tests for the child's continued existence.

Live-verified end-to-end: deployed a 3-node cluster with a real
(XCE_REAL_WORKER=1) worker, confirmed the sudo-parent/root-child PID
pair, ran the fixed stop-all.sh and cleanup.sh and confirmed zero
processes remain after each, with the new "is a sudo wrapper" line
printed.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RLSNJhNoULvVcUhXEFafQC
This commit is contained in:
Rongsong Shen 2026-09-17 02:43:18 +00:00
parent d19e9f2763
commit baa07d78db
No known key found for this signature in database
GPG key ID: 5BCDAAE0123E9FE2
2 changed files with 75 additions and 4 deletions

View file

@ -22291,6 +22291,32 @@
],
"occurrences": 1,
"last_seen": "2026-09-16T17:15:00Z"
},
{
"id": "bug-1820",
"timestamp": "2026-09-17T02:45:00Z",
"error_message": "User report: after deploying a real (root, sudo-launched) xcecd worker via /xce-deploy-ha and stopping the cluster with scripts/stop-all.sh, xcecd keeps running -- ps shows a leftover xcecd process (a different PID than the one stop-all.sh reported stopping) still bound to the deploy dir's logs after stop-all.sh reported \"Stopping worker-1 (PID <pid>)\" with no warning.",
"file": "src/tools/deploy-ha.sh (generated scripts/stop-all.sh and scripts/cleanup.sh kill loops; generated scripts/start-worker.sh's sudo branch)",
"root_cause": "start-worker.sh's real-worker branch writes the pidfile via `echo $$ > \"$PIDFILE\"` and then does `exec sudo \"$WORKER_BIN\" ...` -- `exec` replaces the pidfile-writing shell's own process image with sudo IN PLACE (same PID), so the PID recorded in the pidfile is sudo's own PID, not the actual worker daemon's. sudo then forks a SEPARATE, root-owned child process that execs and runs the real xcecd daemon; sudo itself stays alive as a thin parent/monitor. stop-all.sh's (and cleanup.sh's, identical logic) kill loop did `kill -9 \"$PID\"` against the recorded (sudo) PID -- SIGKILL terminates sudo instantly but is never forwarded to its child (SIGKILL cannot be caught/relayed by the dying parent), so the real xcecd process is silently orphaned (reparented to init) and keeps running. The scripts' own pre-existing \"still alive after kill -9\" warning branch also never fired for this exact case, because it re-checks the SAME (sudo) PID, which genuinely is dead by then -- so the orphaned child produced zero warning output, making the bug fully silent.",
"fix": "FIXED (2026-09-17). In both generated scripts/stop-all.sh and scripts/cleanup.sh (src/tools/deploy-ha.sh), before killing a pidfile'd PID, check whether that PID's own /proc/$PID/cmdline starts with \"sudo \" (the telltale sign left by `exec sudo ...`); if so, find its child process(es) via `pgrep -P \"$PID\"` and kill them first via `sudo kill -9` (they run as root), before killing the sudo PID itself. The post-kill \"still alive\" check was also extended to additionally test for the child PID's continued existence (via `/proc/$CHILD` presence, which needs no kill permission, since `kill -0` on a root-owned PID from a non-root caller returns EPERM regardless of whether the process is alive). Live-verified end-to-end: deployed a fresh 3-node cluster with XCE_REAL_WORKER=1 (forcing the sudo xcecd path), confirmed the exact sudo-parent/root-child PID pair via `ps axwww`, ran the fixed stop-all.sh and confirmed both processes died with the new \"is a sudo wrapper -- also stopping its child\" line printed and zero processes remaining afterward; repeated the same reproduction against cleanup.sh with the same clean result. No unit test exists for this bash tooling (deploy-ha.sh has no meson-registered test suite, consistent with other shell tooling in this project e.g. xce-build.sh); verification is this live end-to-end reproduction.",
"tags": [
"deploy-ha",
"stop-all.sh",
"cleanup.sh",
"start-worker.sh",
"xcecd",
"sudo",
"orphaned-process",
"real-worker",
"sigkill",
"fixed",
"live-verified"
],
"related_bugs": [
"bug-1720"
],
"occurrences": 1,
"last_seen": "2026-09-17T02:45:00Z"
}
]
}