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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDAF5C433F5 for ; Sat, 27 Nov 2021 06:15:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352148AbhK0GSt (ORCPT ); Sat, 27 Nov 2021 01:18:49 -0500 Received: from szxga03-in.huawei.com ([45.249.212.189]:28180 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236810AbhK0GQo (ORCPT ); Sat, 27 Nov 2021 01:16:44 -0500 Received: from canpemm500010.china.huawei.com (unknown [172.30.72.55]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4J1Lpt5hZ1z8vcj; Sat, 27 Nov 2021 14:11:34 +0800 (CST) Received: from [10.174.178.185] (10.174.178.185) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Sat, 27 Nov 2021 14:13:28 +0800 Subject: Re: [PATCH -next] io_uring: Fix undefined-behaviour in io_issue_sqe To: , , , References: <20211118015907.844807-1-yebin10@huawei.com> From: yebin Message-ID: <61A1CC88.9060802@huawei.com> Date: Sat, 27 Nov 2021 14:13:28 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <20211118015907.844807-1-yebin10@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.185] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/11/18 9:59, Ye Bin wrote: > We got issue as follows: > ================================================================================ > UBSAN: Undefined behaviour in ./include/linux/ktime.h:42:14 > signed integer overflow: > -4966321760114568020 * 1000000000 cannot be represented in type 'long long int' > CPU: 1 PID: 2186 Comm: syz-executor.2 Not tainted 4.19.90+ #12 > Hardware name: linux,dummy-virt (DT) > Call trace: > dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78 > show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158 > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x170/0x1dc lib/dump_stack.c:118 > ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161 > handle_overflow+0x188/0x1dc lib/ubsan.c:192 > __ubsan_handle_mul_overflow+0x34/0x44 lib/ubsan.c:213 > ktime_set include/linux/ktime.h:42 [inline] > timespec64_to_ktime include/linux/ktime.h:78 [inline] > io_timeout fs/io_uring.c:5153 [inline] > io_issue_sqe+0x42c8/0x4550 fs/io_uring.c:5599 > __io_queue_sqe+0x1b0/0xbc0 fs/io_uring.c:5988 > io_queue_sqe+0x1ac/0x248 fs/io_uring.c:6067 > io_submit_sqe fs/io_uring.c:6137 [inline] > io_submit_sqes+0xed8/0x1c88 fs/io_uring.c:6331 > __do_sys_io_uring_enter fs/io_uring.c:8170 [inline] > __se_sys_io_uring_enter fs/io_uring.c:8129 [inline] > __arm64_sys_io_uring_enter+0x490/0x980 fs/io_uring.c:8129 > invoke_syscall arch/arm64/kernel/syscall.c:53 [inline] > el0_svc_common+0x374/0x570 arch/arm64/kernel/syscall.c:121 > el0_svc_handler+0x190/0x260 arch/arm64/kernel/syscall.c:190 > el0_svc+0x10/0x218 arch/arm64/kernel/entry.S:1017 > ================================================================================ > > As ktime_set only judge 'secs' if big than KTIME_SEC_MAX, but if we pass > negative value maybe lead to overflow. > To address this issue, we must check if 'sec' is negative. > > Signed-off-by: Ye Bin > --- > fs/io_uring.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index f9e720595860..d8a6446a7921 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -6157,6 +6157,9 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, > if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr))) > return -EFAULT; > > + if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0) > + return -EINVAL; > + > data->mode = io_translate_timeout_mode(flags); > hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode); > ping...