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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 D713CC33CB3 for ; Thu, 16 Jan 2020 18:46:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A45482053B for ; Thu, 16 Jan 2020 18:46:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579200418; bh=eS8mU3QIA0TBXe9Uxh91D1mjEfC0CK2I4ipAljZKsLQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=myT20/5FEviygcxtCp0Lik654Mk65lUaEvx13KfShW6GQ1WZpxmXCZxWi56EdExGe kXhTlskH7u68M0p5W8YAVQyrnGnnhMmhHo7CN91cEM2lwHQcwlmbyG1Oq1QCeynOmM lNTU0A+9vUPqVjNvkC8QFpZGFhwGLSKYWvhkL39M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389846AbgAPRKI (ORCPT ); Thu, 16 Jan 2020 12:10:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:47098 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389800AbgAPRJ7 (ORCPT ); Thu, 16 Jan 2020 12:09:59 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DB15E2081E; Thu, 16 Jan 2020 17:09:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194598; bh=eS8mU3QIA0TBXe9Uxh91D1mjEfC0CK2I4ipAljZKsLQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tHe2yCUo03r9DVV9OR+QMC9NxqzVi8klYDBioAYSF6oyPFRYUdmbXUOnk8ftAGzKt FIA5X36eOJSXh2NCKNHdPVzR/uODwrMqDGB+IEaooo8U5TLiV6jCBlZlxT0BIOXeqa /adMn1qV8wplHBF5+6WknUdz+RpT6Ya14urI2Wng= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Rafael J. Wysocki" , Thomas Gleixner , Sasha Levin , linux-pm@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 467/671] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup() Date: Thu, 16 Jan 2020 12:01:45 -0500 Message-Id: <20200116170509.12787-204-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Rafael J. Wysocki" [ 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) -- 2.20.1