mod_posix: Move POSIX signal handling into util.startup to avoid race
When libunbound is initialized, it spawns a thread to work in.
In case a module initializes libunbound, e.g. by triggering a s2s
connection, Prosody would not handle signals, instead immediately quit
on e.g. the reload (SIGHUP) signal. Likely because the libunbound thread
would not have inherited the signal mask from the main Prosody thread.
Thanks Menel, riau and franck-x for reporting and help narrowing down
--- a/plugins/mod_posix.lua Fri Mar 01 19:22:49 2024 +0100
+++ b/plugins/mod_posix.lua Sat Mar 02 13:23:24 2024 +0100
@@ -15,10 +15,6 @@
.. "Perhaps you need to recompile?", tostring(pposix._VERSION), want_pposix_version);
end
-local have_signal, signal = pcall(require, "prosody.util.signal");
-if not have_signal then
- module:log("warn", "Couldn't load signal library, won't respond to SIGTERM");
-end
local lfs = require "lfs";
local stat = lfs.attributes;
@@ -124,49 +120,3 @@
end
module:hook("server-stopped", remove_pidfile);
-
--- Set signal handlers
-if have_signal then
- module:add_timer(0, function ()
- signal.signal("SIGTERM", function ()
- module:log("warn", "Received SIGTERM");
- prosody.main_thread:run(function ()
- prosody.unlock_globals();
- prosody.shutdown("Received SIGTERM");
- prosody.lock_globals();
- end);
- end);
-
- signal.signal("SIGHUP", function ()
- module:log("info", "Received SIGHUP");
- prosody.main_thread:run(function ()
- prosody.reload_config();
- end);
- -- this also reloads logging
- end);
-
- signal.signal("SIGINT", function ()
- module:log("info", "Received SIGINT");
- prosody.main_thread:run(function ()
- prosody.unlock_globals();
- prosody.shutdown("Received SIGINT");
- prosody.lock_globals();
- end);
- end);
-
- signal.signal("SIGUSR1", function ()
- module:log("info", "Received SIGUSR1");
- module:fire_event("signal/SIGUSR1");
- end);
-
- signal.signal("SIGUSR2", function ()
- module:log("info", "Received SIGUSR2");
- module:fire_event("signal/SIGUSR2");
- end);
- end);
-end
-
--- For other modules to reference
-features = {
- signal_events = true;
-};
--- a/util/startup.lua Fri Mar 01 19:22:49 2024 +0100
+++ b/util/startup.lua Sat Mar 02 13:23:24 2024 +0100
@@ -671,6 +671,48 @@
end
end
+function startup.hook_posix_signals()
+ if prosody.platform ~= "posix" then return end
+ local have_signal, signal = pcall(require, "prosody.util.signal");
+ if not have_signal then
+ log("warn", "Couldn't load signal library, won't respond to SIGTERM");
+ return
+ end
+ signal.signal("SIGTERM", function()
+ log("warn", "Received SIGTERM");
+ prosody.main_thread:run(function()
+ prosody.unlock_globals();
+ prosody.shutdown("Received SIGTERM");
+ prosody.lock_globals();
+ end);
+ end);
+
+ signal.signal("SIGHUP", function()
+ log("info", "Received SIGHUP");
+ prosody.main_thread:run(function() prosody.reload_config(); end);
+ -- this also reloads logging
+ end);
+
+ signal.signal("SIGINT", function()
+ log("info", "Received SIGINT");
+ prosody.main_thread:run(function()
+ prosody.unlock_globals();
+ prosody.shutdown("Received SIGINT");
+ prosody.lock_globals();
+ end);
+ end);
+
+ signal.signal("SIGUSR1", function()
+ log("info", "Received SIGUSR1");
+ fire_event("signal/SIGUSR1");
+ end);
+
+ signal.signal("SIGUSR2", function()
+ log("info", "Received SIGUSR2");
+ fire_event("signal/SIGUSR2");
+ end);
+end
+
function startup.cleanup()
prosody.log("info", "Shutdown status: Cleaning up");
prosody.events.fire_event("server-cleanup");
@@ -748,6 +790,7 @@
startup.init_http_client();
startup.init_data_store();
startup.init_global_protection();
+ startup.hook_posix_signals();
startup.prepare_to_start();
startup.notify_started();
end