From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753791AbaJTLH7 (ORCPT ); Mon, 20 Oct 2014 07:07:59 -0400 Received: from mailout1.w1.samsung.com ([210.118.77.11]:55718 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753542AbaJTLHy (ORCPT ); Mon, 20 Oct 2014 07:07:54 -0400 X-AuditID: cbfec7f5-b7f956d000005ed7-bf-5444ed07cc09 Message-id: <5444ED06.6030008@samsung.com> Date: Mon, 20 Oct 2014 15:07:50 +0400 From: Andrey Ryabinin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.8.1 MIME-version: 1.0 To: Thomas Gleixner Cc: Andrew Morton , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra , Michal Marek , Sasha Levin , x86@kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, "Theodore Ts'o" , Andreas Dilger , Dmitry Vyukov , Konstantin Khlebnikov Subject: kernel: clockevents: shift out-of-bounds References: <1413802499-17928-1-git-send-email-a.ryabinin@samsung.com> In-reply-to: <1413802499-17928-1-git-send-email-a.ryabinin@samsung.com> Content-type: text/plain; charset=UTF-8 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmplkeLIzCtJLcpLzFFi42I5/e/4VV32ty4hBpdf6lt8/dLBYjFn/Ro2 iwkP29gtpm0Ut1jZ+YDV4s+uHUwWl3fNYbO4dGABk0XLvgtMFsd7DzBZLD5ym9li86apzBat PT/ZLX5seMzqwOfRsrncY+esu+weCzaVemxeoeWxaVUnm8e7c+fYPU7M+M3i0XTmKLPHx6e3 WDze77vK5nFmwRF2j8+b5DxOtHxhDeCN4rJJSc3JLEst0rdL4Mo4+vwMS8Ek/oqbxxoYGxj/ 8XQxcnJICJhIXD+ygQnCFpO4cG89G4gtJLCUUeLd4pIuRi4gu5lJYtvsLYwgCV4BLYmuc+tZ QGwWAVWJ87t2M4PYbAJ6Ev9mbQdrFhWIkNi4fgdUvaDEj8n3wOpFBDQkNl66xQwylFngJLPE kj172EESwgKGEtMvz2OB2Owm0X3pENhFnALuEhfm7QVbwCygLjFp3iIoW15i85q3zBMYBWYh 2TELSdksJGULGJlXMYqmliYXFCel5xrpFSfmFpfmpesl5+duYoRE3dcdjEuPWR1iFOBgVOLh 3WHmEiLEmlhWXJl7iFGCg1lJhLf7NlCINyWxsiq1KD++qDQntfgQIxMHp1QDY5+Z2v8ziYs3 rH4w73J4x437Gp6Fh8Mj3jTU6b9+907zRcwWFycZp5pX16O2zV2seuJa1GyP7BDGd7OFFGrF 0kvc1HYoqws8tMt8P23h0gO3v/0ptOf6sn6yqWkS5yqBiadE1i/mTe9dO1tiwlK++VnSm2/v qp/29vtm1tQW2Xv/Te6Wrj0v9ECJpTgj0VCLuag4EQBFQWjJmAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On kernel with UBSan enabled I've got following: UBSan: Undefined behaviour in ../kernel/time/clockevents.c:75:34 shift exponent 32 is to large for 32-bit type 'unsigned int' CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc7+ #39 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 0000000000000000 0000000000000000 0000000000000001 ffffffff83003db0 ffffffff82a30940 0000000000000020 ffffffff83003dc0 ffffffff819502e9 ffffffff83003e40 ffffffff81950735 ffff88013f003233 0000000000000000 Call Trace: dump_stack (/home/andrew/linux/lib/dump_stack.c:52) ubsan_epilogue (/home/andrew/linux/lib/ubsan.c:122) __ubsan_handle_shift_out_of_bounds (/home/andrew/linux/lib/ubsan.c:390) ? hpet_enable (/home/andrew/linux/arch/x86/kernel/hpet.c:862) cev_delta2ns (/home/andrew/linux/kernel/time/clockevents.c:75 (discriminator 1)) clockevents_config.part.2 (/home/andrew/linux/kernel/time/clockevents.c:421) ? __clocksource_select (/home/andrew/linux/kernel/time/clocksource.c:607 /home/andrew/linux/kernel/time/clocksource.c:631) clockevents_config_and_register (/home/andrew/linux/kernel/time/clockevents.c:440) hpet_enable (/home/andrew/linux/arch/x86/kernel/hpet.c:305 /home/andrew/linux/arch/x86/kernel/hpet.c:891) hpet_time_init (/home/andrew/linux/arch/x86/kernel/time.c:79) x86_late_time_init (/home/andrew/linux/arch/x86/kernel/time.c:87) start_kernel (/home/andrew/linux/init/main.c:637) ? early_idt_handlers (/home/andrew/linux/arch/x86/kernel/head_64.S:344) x86_64_start_reservations (/home/andrew/linux/arch/x86/kernel/head64.c:194) x86_64_start_kernel (/home/andrew/linux/arch/x86/kernel/head64.c:183) I guess it should be 1ULL here instead of 1U: (!ismax || evt->mult <= (1U << evt->shift)))