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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 AAC84C2D0DB for ; Fri, 24 Jan 2020 11:27:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80C2B2075D for ; Fri, 24 Jan 2020 11:27:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865258; bh=oiRbZ4IejSTVbITUJfWxW0E+PXGnQSYFhihhwiMoM/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DG9x5S1VBxx0DoByR/0h5sDrMCx278NX9CiACn64/motHxZwL8kmTJT4v0LIopMnx z/pHG3Olw6TthTqt7fapAvGWwUGzlr7wmu/brTftCsXOBKHIWyR000OlPhL0WPkUd4 fSwUlyc/aWALdDQZABHHgL/U3FjtmZAaVnfHheGw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403978AbgAXL1h (ORCPT ); Fri, 24 Jan 2020 06:27:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:43108 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391647AbgAXL1d (ORCPT ); Fri, 24 Jan 2020 06:27:33 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B0CB4214AF; Fri, 24 Jan 2020 11:27:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865251; bh=oiRbZ4IejSTVbITUJfWxW0E+PXGnQSYFhihhwiMoM/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xwpgvKcPCj1CTlOq+jOFVyLn0tc6bgdVh4Tyr3e5izXnttcVgxjwCnf4Hhr6Us39n 3/uomZyCJp0pxh2fOU15WEOLJCwjLtVzvDWhQIEzyjVwsbydzF9pdzTPKbHb9n4DGV 0LZa0xl5LFPyRiAr/Y/f/cvy/nNGscFotqCbXngY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Rafael J. Wysocki" , Thomas Gleixner , Sasha Levin Subject: [PATCH 4.19 482/639] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup() Date: Fri, 24 Jan 2020 10:30:52 +0100 Message-Id: <20200124093148.826111775@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 7c84f64c74f77..2dfa2e0487451 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