From 2933954b71f10d392764f95eec0f0aa2d103054b Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Mon, 15 Jul 2019 13:03:48 +0200
Subject: [PATCH] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup()
Git-commit: 2933954b71f10d392764f95eec0f0aa2d103054b
Patch-mainline: v5.4-rc1
References: bsc#1051510
It is not actually guaranteed that pm_abort_suspend will be
nonzero when pm_system_cancel_wakeup() is called which may lead to
subtle issues, so make it use atomic_dec_if_positive() instead of
atomic_dec() for the safety sake.
Fixes: 33e4f80ee69b ("ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/base/power/wakeup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index ee31d4f8d856..b30c45aad10f 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -859,7 +859,7 @@ EXPORT_SYMBOL_GPL(pm_system_wakeup);
void pm_system_cancel_wakeup(void)
{
- atomic_dec(&pm_abort_suspend);
+ atomic_dec_if_positive(&pm_abort_suspend);
}
void pm_wakeup_clear(bool reset)
--
2.16.4