From e4203b0c9ec9048f58f5aa6a25439e80f6c48487 Mon Sep 17 00:00:00 2001 From: Joachim Wiberg Date: Tue, 12 May 2026 10:45:16 +0200 Subject: [PATCH] package/finit: backport stale-pidfile and death-log fixes Backport two fixes addressing a critical failure reported by a customer: an unclean dbus-daemon exit leaves a lingering /run/messagebus.pid, the daemon then refuse to start, and Finit's restart loop gives up. 0001 service: clean stale pidfile after unclean daemon exit Drop a daemon-owned (pid:!) pidfile when it still names the just-reaped PID and that PID is no longer alive. 0002 service: log signal name and core dumps in death message "by signal: 9" -> "killed by SIGKILL", with ", core dumped" when applicable. Stronger breadcrumb for sudden deaths. Signed-off-by: Joachim Wiberg --- ...ale-pidfile-after-unclean-daemon-exi.patch | 86 +++++++++++++++++++ ...al-name-and-core-dumps-in-death-mess.patch | 50 +++++++++++ 2 files changed, 136 insertions(+) create mode 100644 package/finit/0001-service-clean-stale-pidfile-after-unclean-daemon-exi.patch create mode 100644 package/finit/0002-service-log-signal-name-and-core-dumps-in-death-mess.patch diff --git a/package/finit/0001-service-clean-stale-pidfile-after-unclean-daemon-exi.patch b/package/finit/0001-service-clean-stale-pidfile-after-unclean-daemon-exi.patch new file mode 100644 index 00000000..459bb116 --- /dev/null +++ b/package/finit/0001-service-clean-stale-pidfile-after-unclean-daemon-exi.patch @@ -0,0 +1,86 @@ +From 4a53f610cd05c2aba3da770384460f7e66488ff5 Mon Sep 17 00:00:00 2001 +From: Joachim Wiberg +Date: Mon, 11 May 2026 13:55:11 +0200 +Subject: [PATCH 1/2] service: clean stale pidfile after unclean daemon exit +Organization: Wires + +With `pid:!/path` Finit does not manage the file -- the daemon +creates it on start and removes it on graceful exit. If the daemon +dies before cleanup (SIGKILL, OOM, segfault, exit during startup) +the file lingers and can block the next instance from starting, +e.g. dbus-daemon refuses with EEXIST and the restart loop fails. + +Remove the file when it still names the just-reaped PID and that +PID is no longer alive (the liveness check guards against reuse). +Called from service_cleanup(), and from service_monitor()'s +forking+starting branch where cleanup was previously skipped. + +Signed-off-by: Joachim Wiberg +--- + src/service.c | 36 +++++++++++++++++++++++++++++++++++- + 1 file changed, 35 insertions(+), 1 deletion(-) + +diff --git a/src/service.c b/src/service.c +index 7ed4fceb..e930c4fd 100644 +--- a/src/service.c ++++ b/src/service.c +@@ -1120,6 +1120,35 @@ static void service_notify_stop(svc_t *svc) + } + } + ++/* ++ * Drop a daemon-owned (pid:!) pidfile if it still names the just-reaped ++ * PID and that PID is gone. The liveness check guards against reuse. ++ */ ++static void service_clean_pidfile(svc_t *svc, pid_t reaped) ++{ ++ pid_t pid; ++ char *fn; ++ ++ if (reaped <= 1) ++ return; ++ ++ fn = pid_file(svc); ++ if (!fn) ++ return; ++ ++ pid = pid_file_read(fn); ++ if (pid != reaped || pid_alive(pid)) ++ return; ++ ++ if (remove(fn) && errno != ENOENT) { ++ logit(LOG_CRIT, "Failed removing stale service %s pidfile %s", ++ svc_ident(svc, NULL, 0), fn); ++ return; ++ } ++ ++ dbg("Removed stale service %s pidfile %s", svc_ident(svc, NULL, 0), fn); ++} ++ + /* + * Clean up any lingering state from dead/killed services + */ +@@ -1137,6 +1166,8 @@ static void service_cleanup(svc_t *svc) + if (remove(fn) && errno != ENOENT) + logit(LOG_CRIT, "Failed removing service %s pidfile %s", + svc_ident(svc, NULL, 0), fn); ++ } else if (svc->pidfile[0] == '!') { ++ service_clean_pidfile(svc, svc->pid); + } + + /* +@@ -2405,7 +2436,10 @@ void service_monitor(pid_t lost, int status) + if (svc_is_forking(svc)) { + /* Likely start script exiting */ + if (svc_is_starting(svc)) { +- svc->pid = 0; /* Expect no more activity from this one */ ++ /* Daemon died before clearing 'starting'; drop any stale pidfile. */ ++ service_clean_pidfile(svc, lost); ++ svc->oldpid = lost; /* So service_retry() logs the real PID */ ++ svc->pid = 0; /* Expect no more activity from this one */ + goto cont; + } + +-- +2.43.0 + diff --git a/package/finit/0002-service-log-signal-name-and-core-dumps-in-death-mess.patch b/package/finit/0002-service-log-signal-name-and-core-dumps-in-death-mess.patch new file mode 100644 index 00000000..60ec0375 --- /dev/null +++ b/package/finit/0002-service-log-signal-name-and-core-dumps-in-death-mess.patch @@ -0,0 +1,50 @@ +From 30f2ca3b2e64bce7db1e2d9dcb37a06d53e0b6bf Mon Sep 17 00:00:00 2001 +From: Joachim Wiberg +Date: Mon, 11 May 2026 17:08:25 +0200 +Subject: [PATCH 2/2] service: log signal name and core dumps in death message +Organization: Wires + +Replace the bare signal number ("by signal: 9") with the symbolic +name ("killed by SIGKILL") and annotate when the kernel wrote a +core:("killed by SIGSEGV, core dumped"). Makes the restart line +self-explanatory and gives operators a strong breadcrumb when a +daemon dies unexpectedly. + +Signed-off-by: Joachim Wiberg +--- + src/service.c | 19 ++++++++++++------- + 1 file changed, 12 insertions(+), 7 deletions(-) + +diff --git a/src/service.c b/src/service.c +index e930c4fd..127e0099 100644 +--- a/src/service.c ++++ b/src/service.c +@@ -2828,13 +2828,18 @@ static void service_retry(svc_t *svc) + timeout = ((*restart_cnt) <= (svc->restart_max / 2)) ? 2000 : 5000; + /* If a longer timeout was specified in the conf, use that instead. */ + svc->restart_tmo = max(svc->restart_tmo, timeout); +- logit(LOG_CONSOLE|LOG_WARNING, "Service %s[%d] died (%s%d), restarting (retry in %d msec) (attempt: %d/%d)", +- svc_ident(svc, NULL, 0), svc->oldpid, +- WIFEXITED(svc->status) ? "with exit status: " : "by signal: ", +- WIFEXITED(svc->status) ? WEXITSTATUS(svc->status) : WTERMSIG(svc->status), +- svc->restart_tmo, +- *restart_cnt, +- svc->restart_max); ++ if (WIFEXITED(svc->status)) ++ logit(LOG_CONSOLE|LOG_WARNING, ++ "Service %s[%d] died (exit status: %d), restarting (retry in %d msec) (attempt: %d/%d)", ++ svc_ident(svc, NULL, 0), svc->oldpid, WEXITSTATUS(svc->status), ++ svc->restart_tmo, *restart_cnt, svc->restart_max); ++ else ++ logit(LOG_CONSOLE|LOG_WARNING, ++ "Service %s[%d] died (killed by %s%s), restarting (retry in %d msec) (attempt: %d/%d)", ++ svc_ident(svc, NULL, 0), svc->oldpid, ++ sig_name(WTERMSIG(svc->status)), ++ WCOREDUMP(svc->status) ? ", core dumped" : "", ++ svc->restart_tmo, *restart_cnt, svc->restart_max); + + svc_unblock(svc); + service_step(svc); +-- +2.43.0 +