[PATCH 5.4 117/232] PM: sleep: wakeup: Skip wakeup_source_sysfs_remove() if device is not there
From: Greg Kroah-Hartman
Date:  Thu Apr 16 2020 - 11:21:00 EST
From: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
commit 87de6594dc45dbf6819f3e0ef92f9331c5a9444c upstream.
Skip wakeup_source_sysfs_remove() to fix a NULL pinter dereference via
ws->dev, if the wakeup source is unregistered before registering the
wakeup class from device_add().
Fixes: 2ca3d1ecb8c4 ("PM / wakeup: Register wakeup class kobj after device is added")
Signed-off-by: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
Cc: 5.4+ <stable@xxxxxxxxxxxxxxx> # 5.4+
[ rjw: Subject & changelog, white space ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/base/power/wakeup.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -241,7 +241,9 @@ void wakeup_source_unregister(struct wak
 {
 	if (ws) {
 		wakeup_source_remove(ws);
-		wakeup_source_sysfs_remove(ws);
+		if (ws->dev)
+			wakeup_source_sysfs_remove(ws);
+
 		wakeup_source_destroy(ws);
 	}
 }