From 9311fd211ad6d9779ceae504d63ee1d810f42503 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 15 Jul 2019 13:03:48 +0200 Subject: [PATCH] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup() [ Upstream commit 2933954b71f10d392764f95eec0f0aa2d103054b ] 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 Acked-by: Thomas Gleixner Signed-off-by: Sasha Levin --- 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 7c84f64c74f7..2dfa2e048745 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -875,7 +875,7 @@ 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)