From patchwork Fri Jan 24 09:31:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 233154 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 92669C2D0DB for ; Fri, 24 Jan 2020 10:01:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C73C208C4 for ; Fri, 24 Jan 2020 10:01:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579860096; bh=qys4PTBg21yuijVxAzhvDQXXNLAkLmDpV3GE4iGs2Dw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=x4pUosgKpA8EW6lJhupHwibUZCmFRjQ1pD+XUQ8T4leAbQmCG/FC6AQYMte162T1c 3NyqvXOBFYIBnzATD3QUNAFu3wJEu1I2sbEzcaHsvDebED3roTdcZLj7fPp9T3b8hD AHYH1q+AeUPs5iv4HCxkMqLjOKvEDWY9nFx+kMW0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387807AbgAXKBf (ORCPT ); Fri, 24 Jan 2020 05:01:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:36942 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727215AbgAXKBc (ORCPT ); Fri, 24 Jan 2020 05:01:32 -0500 Received: from localhost (unknown [145.15.244.15]) (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 4F635206D5; Fri, 24 Jan 2020 10:01:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579860092; bh=qys4PTBg21yuijVxAzhvDQXXNLAkLmDpV3GE4iGs2Dw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pkQsarKb5IqHOZ3aw4um9MJj70sKM+ETlpVCxA2SoY3MHNwS7Pp3LWRgEkd7jEgbA 1FEbi270MADGWAbtScf2/SI+RuTC0rl8TWx84scG8YzaBBkvzELqrbVCGOKO8TSYdx VYaa0O5ybvGqObMDhOHo6nufD8rea+V+73thcX/o= 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 4.14 256/343] PM: sleep: Fix possible overflow in pm_system_cancel_wakeup() Date: Fri, 24 Jan 2020 10:31:14 +0100 Message-Id: <20200124092953.735890345@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124092919.490687572@linuxfoundation.org> References: <20200124092919.490687572@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 df53e2b3296b4..877b2a1767a5a 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -877,7 +877,7 @@ 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)