From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753131AbaIOB0z (ORCPT ); Sun, 14 Sep 2014 21:26:55 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:44964 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753027AbaIOB0y (ORCPT ); Sun, 14 Sep 2014 21:26:54 -0400 Message-ID: <5416403D.8010504@huawei.com> Date: Mon, 15 Sep 2014 09:26:21 +0800 From: Wang Nan User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Masami Hiramatsu , Ingo Molnar CC: Thomas Gleixner , Andi Kleen , "Pei Feiyue" , , , Li Zefan Subject: Re: [PATCH] kprobes/x86: opt: free optinsn cache when range check fails References: <1406550019-70935-1-git-send-email-wangnan0@huawei.com> <53D6FC38.8070801@hitachi.com> <53FDCBF1.2020606@huawei.com> <53FDDF08.5090604@hitachi.com> In-Reply-To: <53FDDF08.5090604@hitachi.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.111.69.90] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ingo and Masami, I still unable to find this bugfix in mainline code. Is there any problem? Thank you! On 2014/8/27 21:37, Masami Hiramatsu wrote: > > Hi Ingo, > > Could you pull this for a bugfix of a memory leak? > > (2014/08/27 21:15), Wang Nan wrote: >> On 2014/7/29 9:43, Masami Hiramatsu wrote: >>> (2014/07/28 21:20), Wang Nan wrote: >>>> This patch frees optinsn slot when range check error to prevent memory >>>> leaks. Before this patch, cache entry in kprobe_insn_cache won't be >>>> freed if kprobe optimizing fails due to range check failure. >>>> >>>> Signed-off-by: Wang Nan >>> >>> Oops, thank you for finding it! >>> >>> Acked-by: Masami Hiramatsu >>> >> >> Hi Masami Hiramatsu, >> >> I don't find this patch in newest upstream. Is there any problem? >> >>> BTW, would you really have hit this error? >>> I'd like to know the case if this really happens. >>> >>>> --- >>>> arch/x86/kernel/kprobes/opt.c | 4 +++- >>>> 1 file changed, 3 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c >>>> index f304773..f1314d0 100644 >>>> --- a/arch/x86/kernel/kprobes/opt.c >>>> +++ b/arch/x86/kernel/kprobes/opt.c >>>> @@ -338,8 +338,10 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op) >>>> * a relative jump. >>>> */ >>>> rel = (long)op->optinsn.insn - (long)op->kp.addr + RELATIVEJUMP_SIZE; >>>> - if (abs(rel) > 0x7fffffff) >>>> + if (abs(rel) > 0x7fffffff) { >>>> + __arch_remove_optimized_kprobe(op, 0); >>>> return -ERANGE; >>>> + } >>>> >>>> buf = (u8 *)op->optinsn.insn; >>>> >>>> >>> >>> >> >> >> > >