From 5ed20345db356121bc72e0092c17b74e2de67ff7 Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Tue, 14 Dec 2021 15:38:12 +0900
Subject: [PATCH] home: fix heap-use-after-free

`bus_home_emit_remove()` may be called from manager_free() -> home_free().
In that case, manager->bus is already unref()ed.

Fixes #21767.

(cherry picked from commit 2ff457720bd3bc59985e807b748f6305bdf27826)

Conflict:NA
Reference:https://github.com/systemd/systemd/commit/5ed20345db356121bc72e0092c17b74e2de67ff7
---
 src/home/homed-home-bus.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/home/homed-home-bus.c b/src/home/homed-home-bus.c
index c71256d15e..601ecc5cf5 100644
--- a/src/home/homed-home-bus.c
+++ b/src/home/homed-home-bus.c
@@ -940,6 +940,12 @@ int bus_home_emit_remove(Home *h) {
         if (!h->announced)
                 return 0;
 
+        if (!h->manager)
+                return 0;
+
+        if (!h->manager->bus)
+                return 0;
+
         r = bus_home_path(h, &path);
         if (r < 0)
                 return r;
-- 
2.33.0