systemd/0359-core-unit-search-shared-namespace-in-transitive-rela.patch

From 7ce47c0fc8b624d08f238f5ef364275ec8a791f5 Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Thu, 25 May 2023 18:08:37 +0900
Subject: [PATCH] core/unit: search shared namespace in transitive relation of
 JoinsNamespaceOf=

Previously, dependency chain of JoinsNamespaceOf= did not work, e.g.
- a.service has JoinsNamespaceOf=b.service
- b.service has JoinsNamespaceOf=c.service
if, first c.service, next a.service, finally b.service is started,
then a.service is not joined to the namespace of c.service. And, as
mentioned in the document, the namespace used by b.service is not
deterministic.

This makes when searching exsiting namespace to be joined, all units in
the transitive dependency of JoinsNamespaceOf= are checked.

(cherry picked from commit 83123a44989c095f9b7a89841db9917417fc451a)

Related: #2213521
---
 src/core/unit.c                               | 36 ++++++++++++++++++-
 src/core/unit.h                               |  1 +
 .../testsuite-23-joins-namespace-of-7.service |  2 +-
 .../testsuite-23-joins-namespace-of-8.service |  2 +-
 .../testsuite-23-joins-namespace-of-9.service |  6 ++--
 5 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/src/core/unit.c b/src/core/unit.c
index 8b66139ad9..6acc63e091 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -4718,6 +4718,7 @@ int unit_require_mounts_for(Unit *u, const char *path, UnitDependencyMask mask)
 }
 
 int unit_setup_exec_runtime(Unit *u) {
+        _cleanup_set_free_ Set *units = NULL;
         ExecRuntime **rt;
         size_t offset;
         Unit *other;
@@ -4731,9 +4732,15 @@ int unit_setup_exec_runtime(Unit *u) {
         if (*rt)
                 return 0;
 
+        r = unit_get_transitive_dependency_set(u, UNIT_ATOM_JOINS_NAMESPACE_OF, &units);
+        if (r < 0)
+                return r;
+
         /* Try to get it from somebody else */
-        UNIT_FOREACH_DEPENDENCY(other, u, UNIT_ATOM_JOINS_NAMESPACE_OF) {
+        SET_FOREACH(other, units) {
                 r = exec_runtime_acquire(u->manager, NULL, other->id, false, rt);
+                if (r < 0)
+                        return r;
                 if (r == 1)
                         return 1;
         }
@@ -5921,6 +5928,33 @@ int unit_get_dependency_array(const Unit *u, UnitDependencyAtom atom, Unit ***re
         return (int) n;
 }
 
+int unit_get_transitive_dependency_set(Unit *u, UnitDependencyAtom atom, Set **ret) {
+        _cleanup_set_free_ Set *units = NULL, *queue = NULL;
+        Unit *other;
+        int r;
+
+        assert(u);
+        assert(ret);
+
+        /* Similar to unit_get_dependency_array(), but also search the same dependency in other units. */
+
+        do {
+                UNIT_FOREACH_DEPENDENCY(other, u, atom) {
+                        r = set_ensure_put(&units, NULL, other);
+                        if (r < 0)
+                                return r;
+                        if (r == 0)
+                                continue;
+                        r = set_ensure_put(&queue, NULL, other);
+                        if (r < 0)
+                                return r;
+                }
+        } while ((u = set_steal_first(queue)));
+
+        *ret = TAKE_PTR(units);
+        return 0;
+}
+
 const ActivationDetailsVTable * const activation_details_vtable[_UNIT_TYPE_MAX] = {
         [UNIT_PATH] = &activation_details_path_vtable,
         [UNIT_TIMER] = &activation_details_timer_vtable,
diff --git a/src/core/unit.h b/src/core/unit.h
index 3bc7de3d1c..e79b5322b4 100644
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -805,6 +805,7 @@ static inline const UnitVTable* UNIT_VTABLE(const Unit *u) {
 
 Unit* unit_has_dependency(const Unit *u, UnitDependencyAtom atom, Unit *other);
 int unit_get_dependency_array(const Unit *u, UnitDependencyAtom atom, Unit ***ret_array);
+int unit_get_transitive_dependency_set(Unit *u, UnitDependencyAtom atom, Set **ret);
 
 static inline Hashmap* unit_get_dependencies(Unit *u, UnitDependency d) {
         return hashmap_get(u->dependencies, UNIT_DEPENDENCY_TO_PTR(d));
diff --git a/test/testsuite-23.units/testsuite-23-joins-namespace-of-7.service b/test/testsuite-23.units/testsuite-23-joins-namespace-of-7.service
index 6c7bbdb097..60c083a3f4 100644
--- a/test/testsuite-23.units/testsuite-23-joins-namespace-of-7.service
+++ b/test/testsuite-23.units/testsuite-23-joins-namespace-of-7.service
@@ -6,6 +6,6 @@ JoinsNamespaceOf=testsuite-23-joins-namespace-of-8.service
 Type=oneshot
 MountAPIVFS=yes
 PrivateTmp=yes
-ExecStart=test ! -e /tmp/shared-private-file-x
+ExecStart=test -e /tmp/shared-private-file-x
 ExecStart=test ! -e /tmp/shared-private-file-y
 ExecStart=touch /tmp/hoge
diff --git a/test/testsuite-23.units/testsuite-23-joins-namespace-of-8.service b/test/testsuite-23.units/testsuite-23-joins-namespace-of-8.service
index 42053b99f8..dac1cea7bd 100644
--- a/test/testsuite-23.units/testsuite-23-joins-namespace-of-8.service
+++ b/test/testsuite-23.units/testsuite-23-joins-namespace-of-8.service
@@ -5,5 +5,5 @@ NotifyAccess=all
 MountAPIVFS=yes
 PrivateTmp=yes
 ExecStartPre=test -e /tmp/shared-private-file-x
-ExecStartPre=test ! -e /tmp/hoge
+ExecStartPre=test -e /tmp/hoge
 ExecStart=/bin/bash -c 'touch /tmp/shared-private-file-y && systemd-notify --ready && sleep infinity'
diff --git a/test/testsuite-23.units/testsuite-23-joins-namespace-of-9.service b/test/testsuite-23.units/testsuite-23-joins-namespace-of-9.service
index a50a7fcdc2..6c64873b24 100644
--- a/test/testsuite-23.units/testsuite-23-joins-namespace-of-9.service
+++ b/test/testsuite-23.units/testsuite-23-joins-namespace-of-9.service
@@ -6,6 +6,6 @@ JoinsNamespaceOf=testsuite-23-joins-namespace-of-8.service
 Type=oneshot
 MountAPIVFS=yes
 PrivateTmp=yes
-ExecStart=test ! -e /tmp/shared-private-file-x
-ExecStart=test ! -e /tmp/shared-private-file-y
-ExecStart=test ! -e /tmp/hoge
+ExecStart=test -e /tmp/shared-private-file-x
+ExecStart=test -e /tmp/shared-private-file-y
+ExecStart=test -e /tmp/hoge