From 670866f0349229045c5cddaeb08f07347bb7583b Mon Sep 17 00:00:00 2001
From: cmss_dx <dingxiang@cmss.chinamobile.com>
Date: Tue, 29 Nov 2022 02:12:06 +0000
Subject: [PATCH 01/17] chardev: fix segfault in finalize
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mainline inclusion
from mainline-v7.2.0-rc2
commit fc0c128531ed55f058bfbad4f1348ebd9a0187f2
category: bugfix

-----------------------

If finalize chardev-msmouse or chardev-wctable is called immediately after
init it cases QEMU to crash with segfault. This happens because of
QTAILQ_REMOVE in qemu_input_handler_unregister tries to dereference
NULL pointer.
For instance, this error can be reproduced via qom-list-properties
command.

Signed-off-by: Maksim Davydov davydov-max@yandex-team.ru
Reviewed-by: Marc-André Lureau marcandre.lureau@redhat.com
Reviewed-by: Vladimir Sementsov-Ogievskiy vsementsov@yandex-team.ru
Message-Id: 20220825165247.33704-1-davydov-max@yandex-team.ru

Signed-off-by: cmss_dx <dingxiang@cmss.chinamobile.com>
---
 chardev/msmouse.c  | 4 +++-
 chardev/wctablet.c | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/chardev/msmouse.c b/chardev/msmouse.c
index eb9231dcdb..2cc1b16561 100644
--- a/chardev/msmouse.c
+++ b/chardev/msmouse.c
@@ -146,7 +146,9 @@ static void char_msmouse_finalize(Object *obj)
 {
     MouseChardev *mouse = MOUSE_CHARDEV(obj);
 
-    qemu_input_handler_unregister(mouse->hs);
+    if (mouse->hs) {
+        qemu_input_handler_unregister(mouse->hs);
+    }
 }
 
 static QemuInputHandler msmouse_handler = {
diff --git a/chardev/wctablet.c b/chardev/wctablet.c
index e8b292c43c..43bdf6b608 100644
--- a/chardev/wctablet.c
+++ b/chardev/wctablet.c
@@ -319,7 +319,9 @@ static void wctablet_chr_finalize(Object *obj)
 {
     TabletChardev *tablet = WCTABLET_CHARDEV(obj);
 
-    qemu_input_handler_unregister(tablet->hs);
+    if (tablet->hs) {
+        qemu_input_handler_unregister(tablet->hs);
+    }
 }
 
 static void wctablet_chr_open(Chardev *chr,
-- 
2.27.0