fix #5009: avoid waiting for stdout eof of /etc/network/ scripts

[ifupdown2.git] / debian / patches / upstream / 0001-scheduler-avoid-waiting-for-stdout-eof-of-etc-networ.patch

diff --git a/debian/patches/upstream/0001-scheduler-avoid-waiting-for-stdout-eof-of-etc-networ.patch b/debian/patches/upstream/0001-scheduler-avoid-waiting-for-stdout-eof-of-etc-networ.patch
new file mode 100644 (file)
index 0000000..e377e56
--- /dev/null
+++ b/debian/patches/upstream/0001-scheduler-avoid-waiting-for-stdout-eof-of-etc-networ.patch
@@ -0,0 +1,44 @@
+From 1303d9211d82326f7c55d56db13eed66bb1c6535 Mon Sep 17 00:00:00 2001
+From: Friedrich Weber <f.weber@proxmox.com>
+Date: Tue, 26 Sep 2023 13:33:36 +0200
+Subject: [PATCH] scheduler: avoid waiting for stdout eof of /etc/network/
+ scripts
+
+Scripts in /etc/network/ are executed using `exec_command` which
+captures stdout by default, and thus waits for stdout end-of-file via
+`Popen.communicate()`. However, this can cause hangs if the network
+script executes a long-running command in the background. Can be
+reproduced by putting the following (executable) script in
+/etc/network/if-up.d/:
+
+       #!/bin/sh
+       sleep 5&
+
+This script will cause `ifreload -a` to wait for 5 seconds per network
+interface.
+
+To avoid waiting, do not capture stdout when executing /etc/network/
+scripts. This also improves compatibility with ifupdown, which runs
+the above script in the background.
+
+Signed-off-by: Friedrich Weber <f.weber@proxmox.com>
+---
+ ifupdown2/ifupdown/scheduler.py | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/ifupdown2/ifupdown/scheduler.py b/ifupdown2/ifupdown/scheduler.py
+index fda6ff2..e4d579f 100644
+--- a/ifupdown2/ifupdown/scheduler.py
++++ b/ifupdown2/ifupdown/scheduler.py
+@@ -142,7 +142,7 @@ class ifaceScheduler():
+             for mname in ifupdownobj.script_ops.get(op, []):
+                 ifupdownobj.logger.debug("%s: %s : running script %s" % (ifacename, op, mname))
+                 try:
+-                    utils.exec_command(mname, env=command_env)
++                    utils.exec_command(mname, env=command_env, stdout=False)
+                 except Exception as e:
+                     if "permission denied" in str(e).lower():
+                         ifupdownobj.logger.warning('%s: %s %s' % (ifacename, op, str(e)))
+-- 
+2.39.2
+