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=-12.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 F1FF7C282DF for ; Fri, 19 Apr 2019 19:03:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC86D2064A for ; Fri, 19 Apr 2019 19:03:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="TNki1vF/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729240AbfDSTD6 (ORCPT ); Fri, 19 Apr 2019 15:03:58 -0400 Received: from terminus.zytor.com ([198.137.202.136]:42949 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729199AbfDSTD4 (ORCPT ); Fri, 19 Apr 2019 15:03:56 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x3JCGxQE265334 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Fri, 19 Apr 2019 05:16:59 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 terminus.zytor.com x3JCGxQE265334 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2019041745; t=1555676220; bh=oMquC4Hqs+4PBwEW4SZwEz0ab5O6GnBFepmZPk2AUlg=; h=Date:From:Cc:Reply-To:In-Reply-To:References:To:Subject:From; b=TNki1vF/ryTh4tmJQ//3b7q+C5MblTGg7f8crbLPJMcyGfuTxgQ9XT/OAOusCTJma G5vxOpXqdFr9ocAZhR7hlQZOg1wYR9Lps9BKY2M2DlRSQUS5Aptz6CqgrrcKdhwfbW Mrmzwp/5DMYw8V+DXY4WTvDjiNvfcP/BWtfHygq+CauH9wxNMUEwJMeSq6cbix6E3D bFKnxoAx3/hZRmzCE9aFFjT7pOt4bCrwqbW//XXp38oa/TDK9VNUWwrOl358SX+efV 6LKOtdIQ+c+qA+BU77Tl2Vo9JiTqLOHfYdjTM7LDY56Q1lW72GruKtmBCrhQo1bdLo 0HDMgg3dYQiJg== Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x3JCGwqr265331; Fri, 19 Apr 2019 05:16:58 -0700 Date: Fri, 19 Apr 2019 05:16:58 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Konstantin Khlebnikov Message-ID: Cc: tglx@linutronix.de, a.p.zijlstra@chello.nl, hpa@zytor.com, khlebnikov@yandex-team.ru, peterz@infradead.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, mingo@kernel.org Reply-To: khlebnikov@yandex-team.ru, hpa@zytor.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@kernel.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, peterz@infradead.org In-Reply-To: <155125501891.293431.3345233332801109696.stgit@buzz> References: <155125501891.293431.3345233332801109696.stgit@buzz> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/core: Handle overflow in cpu_shares_write_u64 Git-Commit-ID: 5b61d50ab4ef590f5e1d4df15cd2cea5f5715308 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 5b61d50ab4ef590f5e1d4df15cd2cea5f5715308 Gitweb: https://git.kernel.org/tip/5b61d50ab4ef590f5e1d4df15cd2cea5f5715308 Author: Konstantin Khlebnikov AuthorDate: Wed, 27 Feb 2019 11:10:18 +0300 Committer: Ingo Molnar CommitDate: Fri, 19 Apr 2019 13:42:10 +0200 sched/core: Handle overflow in cpu_shares_write_u64 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 --- kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fb09eaad1d3a..685b1541ce51 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6507,6 +6507,8 @@ 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)); }