From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3056DC76195 for ; Tue, 16 Jul 2019 16:27:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 13E3821743 for ; Tue, 16 Jul 2019 16:27:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388096AbfGPQ1S (ORCPT ); Tue, 16 Jul 2019 12:27:18 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:53371 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388046AbfGPQ1S (ORCPT ); Tue, 16 Jul 2019 12:27:18 -0400 Received: from 79.184.255.39.ipv4.supernova.orange.pl (79.184.255.39) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.267) id 50c6e6fd674ef2b9; Tue, 16 Jul 2019 18:27:15 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: Linux ACPI , LKML , Len Brown , Srinivas Pandruvada , Thomas Gleixner , Rajneesh Bhardwaj , "David E. Box" Subject: [PATCH 4/8] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup() Date: Tue, 16 Jul 2019 18:14:58 +0200 Message-ID: <2970489.lynJ6BP8VZ@kreacher> In-Reply-To: <71085220.z6FKkvYQPX@kreacher> References: <71085220.z6FKkvYQPX@kreacher> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki 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 --- drivers/base/power/wakeup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-pm/drivers/base/power/wakeup.c =================================================================== --- linux-pm.orig/drivers/base/power/wakeup.c +++ linux-pm/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)