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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,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 1DF39C072B1 for ; Thu, 30 May 2019 04:09:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D97D025115 for ; Thu, 30 May 2019 04:09:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559189361; bh=Sggf7DE/dWqdGOyyTn7HrVZ2bSeYDvsNmoVhtkxp1Tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jzzl33kmIaxogtahJKRZkllUwfUtF4AjX1oPEpmaYg8s57rQ/dnR1pe2CIzhTscVP 86zmncQNAomNIDamI9SHIU2QQCW31tizJY+PkF8xS69pLdX+cqjaPICn4lcE0faZpn KX1Ha2MvwhdxTKuW8kid9eex0FctmRgDNrnpBoaQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727110AbfE3EJU (ORCPT ); Thu, 30 May 2019 00:09:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:45502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730963AbfE3DRN (ORCPT ); Wed, 29 May 2019 23:17:13 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 8934824667; Thu, 30 May 2019 03:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559186232; bh=Sggf7DE/dWqdGOyyTn7HrVZ2bSeYDvsNmoVhtkxp1Tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ybYMDG7pNuUiujDHnVoCG0mHWhOIKNW5+JarrZStXJ2L9AcwX4/6oNP0Z9H1iR896 kGT0uYedBmkpAuAZHhIqkAyra0vjPw0szrax90W5SoPv0mPdp3U6i/t3NP0N5yXjW5 4N0HqrUHKlDrxwc74IOx+EgZwCQsxdLlQV0UGqRs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Konstantin Khlebnikov , Peter Zijlstra , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Sasha Levin Subject: [PATCH 4.19 138/276] sched/core: Handle overflow in cpu_shares_write_u64 Date: Wed, 29 May 2019 20:04:56 -0700 Message-Id: <20190530030534.341055704@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030523.133519668@linuxfoundation.org> References: <20190530030523.133519668@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 [ Upstream commit 5b61d50ab4ef590f5e1d4df15cd2cea5f5715308 ] Bit shift in scale_load() could overflow shares. This patch saturates it to MAX_SHARES like following sched_group_set_shares(). Example: # echo 9223372036854776832 > cpu.shares # cat cpu.shares Before patch: 1024 After pattch: 262144 Signed-off-by: Konstantin Khlebnikov Acked-by: Peter Zijlstra Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/155125501891.293431.3345233332801109696.stgit@buzz Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bd5ae34c20c0b..6138754e5030f 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6491,6 +6491,8 @@ static void cpu_cgroup_attach(struct cgroup_taskset *tset) static int cpu_shares_write_u64(struct cgroup_subsys_state *css, struct cftype *cftype, u64 shareval) { + if (shareval > scale_load_down(ULONG_MAX)) + shareval = MAX_SHARES; return sched_group_set_shares(css_tg(css), scale_load(shareval)); } -- 2.20.1