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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 1B4BCC282C2 for ; Thu, 7 Feb 2019 11:44:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE66B21907 for ; Thu, 7 Feb 2019 11:44:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549539855; bh=udosWZycVKCmAzWF5oS75tmvz342lbikJ3DehgwMCmg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1amCtK5Tbox2g6Y31QHKeUqOyJnsNlW5iXpyZ5H6Ky5cgjAU5nIVGqoAmTQhhQUMC 3HSl4ip4sWIxHfkaCVEneQVe9Ak3c4H4GHECdbPNNzU/P6dIOJQwXTlyCYMVFGJaIR 3RbOmfQAwgr7OH2XGWk78TEHdgltbQ81Qh25lQWY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727662AbfBGLoJ (ORCPT ); Thu, 7 Feb 2019 06:44:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:34660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727677AbfBGLoG (ORCPT ); Thu, 7 Feb 2019 06:44:06 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 D5C702080F; Thu, 7 Feb 2019 11:44:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549539845; bh=udosWZycVKCmAzWF5oS75tmvz342lbikJ3DehgwMCmg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Exavx/wGawBXL50PDh7VgqEvHtVSBrm9oBjfTvcZmEtxSXHqyt4cCz9ecpZLMf9G5 G18qPmrrL1HR5wKY4B8goFpXgIO+RplWBGKauSKLfcmF51A2y/E+6MxTJdZ/b8+qC9 DpE5PxPaCMknsbpwGZDwVbhGTINXIkPoU1qWlJ3I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Paul E. McKenney" , "Rantala, Tommi" Subject: [PATCH 4.4 34/34] rcu: Force boolean subscript for expedited stall warnings Date: Thu, 7 Feb 2019 12:42:16 +0100 Message-Id: <20190207113026.866667243@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190207113025.552605181@linuxfoundation.org> References: <20190207113025.552605181@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul E. McKenney commit ec3833ed02ae6ef2a933ece9de7cbab0c64c699e upstream. The cpu_online() function can return values other than 0 and 1, which can result in subscript overflow when applied to a two-element array. This commit allows for this behavior by using "!!" on the return value from cpu_online() when used as a subscript. Signed-off-by: Paul E. McKenney Cc: "Rantala, Tommi" Signed-off-by: Greg Kroah-Hartman --- kernel/rcu/tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3817,7 +3817,7 @@ static void synchronize_sched_expedited_ continue; rdp = per_cpu_ptr(rsp->rda, cpu); pr_cont(" %d-%c%c%c", cpu, - "O."[cpu_online(cpu)], + "O."[!!cpu_online(cpu)], "o."[!!(rdp->grpmask & rnp->expmaskinit)], "N."[!!(rdp->grpmask & rnp->expmaskinitnext)]); }