From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CDC411F150B; Thu, 20 Feb 2025 12:01:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.190 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740052919; cv=none; b=TE+R2XyazMT+T+oYfCnJWhkhifiY3Km4vQIz99XZkIsU8BsowH+Omxj/t0eezKAEbVeohpCL/FhamJ6BqQ404rNbzEj5RM/95cHaxgM7666dkg0MZyAi0zWiv2ChP/ZNDxT76S2Bo95ZxoXamWPtJlfuX3BlSEdkRb13No4/NtM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740052919; c=relaxed/simple; bh=xC4t5PNFRGnqdbnDdkkrRiU383ecZkkQlQNaoeaxAAo=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=jNqj5JFPaPuuhVa6zTwqI3GwldQn5d5vdKHd9E4sI7PmeuWBwL7aDWNnFd6WFT5/vo9oa3Nf6hMtqRBGwZg0J+bSaBY/R/q4znjuC9ivfECyNc1Ph1ZBUQkB6CU/bL5J9u+Xcy7rs6GJUSFRTE0wvScmsuHg8GbQg3Emmz/hE/g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.190 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.44]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4YzBcW1pQBz21mxG; Thu, 20 Feb 2025 19:58:51 +0800 (CST) Received: from kwepemk500005.china.huawei.com (unknown [7.202.194.90]) by mail.maildlp.com (Postfix) with ESMTPS id BA519140360; Thu, 20 Feb 2025 20:01:52 +0800 (CST) Received: from [10.174.179.234] (10.174.179.234) by kwepemk500005.china.huawei.com (7.202.194.90) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 20 Feb 2025 20:01:51 +0800 Message-ID: <85725388-180b-267c-e121-3af1f1b75f94@huawei.com> Date: Thu, 20 Feb 2025 20:01:50 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: Add Morton,Peter and David for discussion//Re: [PATCH -next] uprobes: fix two zero old_folio bugs in __replace_page() To: David Hildenbrand , Oleg Nesterov CC: Masami Hiramatsu , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , Andrew Morton , Peter Xu , , , , , , linux-mm References: <20250217123826.88503-1-tongtiangen@huawei.com> <3b893634-5453-42d0-b8dc-e9d07988e9e9@redhat.com> <24a61833-f389-b074-0d9c-d5ad9efc2046@huawei.com> <20250219152237.GB5948@redhat.com> <34e18c47-e536-48e4-80ca-7c7bbc75ecce@redhat.com> <2fe4c4d1-c480-c250-1ba2-1a82caf5d7fa@huawei.com> <196fc7d8-30a8-439a-89bd-57353fd98df8@redhat.com> From: Tong Tiangen In-Reply-To: <196fc7d8-30a8-439a-89bd-57353fd98df8@redhat.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemk500005.china.huawei.com (7.202.194.90) 在 2025/2/20 16:38, David Hildenbrand 写道: > On 20.02.25 03:31, Tong Tiangen wrote: >> >> >> 在 2025/2/20 0:12, David Hildenbrand 写道: >>> On 19.02.25 16:22, Oleg Nesterov wrote: >>>> On 02/18, Tong Tiangen wrote: >>>>> >>>>> OK, Before your rewrite last merged, How about i change the >>>>> solution to >>>>> just reject them immediately after get_user_page_vma_remote()？ >>>> >>>> I agree, uprobe_write_opcode() should simply fail if >>>> is_zero_page(old_page). >>> >>> Yes. That's currently only syzkaller that triggers it, not some sane use >>> case. >> >> OK, change as follows: >> >> --- a/kernel/events/uprobes.c >> +++ b/kernel/events/uprobes.c >> @@ -506,6 +506,12 @@ int uprobe_write_opcode(struct arch_uprobe >> *auprobe, struct mm_struct *mm, >>           if (ret <= 0) >>                   goto put_old; >> >> +       if (WARN(is_zero_page(old_page), > > This can likely be triggered by user space, so do not use WARN. OK,thanks. Hi Oleg, is that all right? Thanks, Tong. >