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=-14.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 D3054C433ED for ; Tue, 6 Apr 2021 11:09:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 936166139B for ; Tue, 6 Apr 2021 11:09:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234119AbhDFLJE (ORCPT ); Tue, 6 Apr 2021 07:09:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232290AbhDFLJD (ORCPT ); Tue, 6 Apr 2021 07:09:03 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B79E3C06174A; Tue, 6 Apr 2021 04:08:55 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id f6so7671802wrv.12; Tue, 06 Apr 2021 04:08:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:cc:references:from:autocrypt:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=iiqRrCWUZIueVHnEVy2DV3+c6C09yobx7qcNjqDEblA=; b=Gxj1u1eiMrZ8JKfJZ6friWoQLprvfnVw3Rq2H4Moa67AHCsKSON58b0XhE4ta2iKBB LJ28GD16zJSlcqfQ+FfkJbc8qoPCTMAa4OTSRy5qE6f/yrqpbe9lkDvTF3kJjPQLtlJ3 KwmHAcEVOFojq0FSDpUQ3xmgNjzRXZbByZAIjmbqoEGWETe6GAqGX1+08XgHipjFSL// iwGVIUQ87ZUVtscccM5y7ZAOXRK0vmF3w9RIi6IGtUi5vlg6+2e6NuyVKF1S532ldjCI udMXLiyMTI19O1MDtx1PUHl6gNC2qbJ/44gPLUSOhKHbzj6WzNHcEZT/zYuuf//3womr kLvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:references:from:autocrypt:subject :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=iiqRrCWUZIueVHnEVy2DV3+c6C09yobx7qcNjqDEblA=; b=Yqdsxd1SlHB6TLN3ESnxIcY1TAfWziHStknsxNFdzznClYs2liO5mmWUXymPoSut9z NIizTC6xsHw9WudpynX9vKVQwmNkkfx5LBkkK4xnADsrga3xrZYO7TI9ImTyNkgKr6my zvD74yWm2v5vo0X2bDcw54+wNtR/9i39Op7hBrlr9wKyAlOysjy5eE9wSF2lwAyXhtUc Tye81pLFM09zZ5PaqZ+5ag7/8TATSZ8HpzNuLAF+vlE5GMK2fYozEO6vmJrdGoWrx11a IkT3n7WCQsBVkzK/6GfZOQq4Tqp+XiBcj3RCNIfBpnM0p72xU51WEbzvVf7r1vjEpBrg +dHQ== X-Gm-Message-State: AOAM532OD+7YILvsLgIglbQb4hD5f/SBWcnk9MorLplQxwymrHnIhOAE UJKcWIDzTqZO2A3b1go/OndK0tMO9xLwJQ== X-Google-Smtp-Source: ABdhPJxLVxToGzabpVSbcWQfG61qrSnCU/9SiS1kB3NqAobjceiaxf4N/4FPeUvJjAOIuqH4k+9gTA== X-Received: by 2002:adf:deca:: with SMTP id i10mr15962911wrn.319.1617707334233; Tue, 06 Apr 2021 04:08:54 -0700 (PDT) Received: from [192.168.8.143] ([185.69.145.134]) by smtp.gmail.com with ESMTPSA id b5sm244817wri.57.2021.04.06.04.08.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 06 Apr 2021 04:08:53 -0700 (PDT) To: yangerkun , viro@zeniv.linux.org.uk, axboe@kernel.dk Cc: linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, io-uring@vger.kernel.org References: <20210401071807.3328235-1-yangerkun@huawei.com> <3bd14a60-b259-377b-38d5-907780bc2416@huawei.com> From: Pavel Begunkov Autocrypt: addr=asml.silence@gmail.com; prefer-encrypt=mutual; keydata= mQINBFmKBOQBEAC76ZFxLAKpDw0bKQ8CEiYJRGn8MHTUhURL02/7n1t0HkKQx2K1fCXClbps bdwSHrhOWdW61pmfMbDYbTj6ZvGRvhoLWfGkzujB2wjNcbNTXIoOzJEGISHaPf6E2IQx1ik9 6uqVkK1OMb7qRvKH0i7HYP4WJzYbEWVyLiAxUj611mC9tgd73oqZ2pLYzGTqF2j6a/obaqha +hXuWTvpDQXqcOZJXIW43atprH03G1tQs7VwR21Q1eq6Yvy2ESLdc38EqCszBfQRMmKy+cfp W3U9Mb1w0L680pXrONcnlDBCN7/sghGeMHjGKfNANjPc+0hzz3rApPxpoE7HC1uRiwC4et83 CKnncH1l7zgeBT9Oa3qEiBlaa1ZCBqrA4dY+z5fWJYjMpwI1SNp37RtF8fKXbKQg+JuUjAa9 Y6oXeyEvDHMyJYMcinl6xCqCBAXPHnHmawkMMgjr3BBRzODmMr+CPVvnYe7BFYfoajzqzq+h EyXSl3aBf0IDPTqSUrhbmjj5OEOYgRW5p+mdYtY1cXeK8copmd+fd/eTkghok5li58AojCba jRjp7zVOLOjDlpxxiKhuFmpV4yWNh5JJaTbwCRSd04sCcDNlJj+TehTr+o1QiORzc2t+N5iJ NbILft19Izdn8U39T5oWiynqa1qCLgbuFtnYx1HlUq/HvAm+kwARAQABtDFQYXZlbCBCZWd1 bmtvdiAoc2lsZW5jZSkgPGFzbWwuc2lsZW5jZUBnbWFpbC5jb20+iQJOBBMBCAA4FiEE+6Ju PTjTbx479o3OWt5b1Glr+6UFAlmKBOQCGwMFCwkIBwIGFQgJCgsCBBYCAwECHgECF4AACgkQ Wt5b1Glr+6WxZA//QueaKHzgdnOikJ7NA/Vq8FmhRlwgtP0+E+w93kL+ZGLzS/cUCIjn2f4Q Mcutj2Neg0CcYPX3b2nJiKr5Vn0rjJ/suiaOa1h1KzyNTOmxnsqE5fmxOf6C6x+NKE18I5Jy xzLQoktbdDVA7JfB1itt6iWSNoOTVcvFyvfe5ggy6FSCcP+m1RlR58XxVLH+qlAvxxOeEr/e aQfUzrs7gqdSd9zQGEZo0jtuBiB7k98t9y0oC9Jz0PJdvaj1NZUgtXG9pEtww3LdeXP/TkFl HBSxVflzeoFaj4UAuy8+uve7ya/ECNCc8kk0VYaEjoVrzJcYdKP583iRhOLlZA6HEmn/+Gh9 4orG67HNiJlbFiW3whxGizWsrtFNLsSP1YrEReYk9j1SoUHHzsu+ZtNfKuHIhK0sU07G1OPN 2rDLlzUWR9Jc22INAkhVHOogOcc5ajMGhgWcBJMLCoi219HlX69LIDu3Y34uIg9QPZIC2jwr 24W0kxmK6avJr7+n4o8m6sOJvhlumSp5TSNhRiKvAHB1I2JB8Q1yZCIPzx+w1ALxuoWiCdwV M/azguU42R17IuBzK0S3hPjXpEi2sK/k4pEPnHVUv9Cu09HCNnd6BRfFGjo8M9kZvw360gC1 reeMdqGjwQ68o9x0R7NBRrtUOh48TDLXCANAg97wjPoy37dQE7e5Ag0EWYoE5AEQAMWS+aBV IJtCjwtfCOV98NamFpDEjBMrCAfLm7wZlmXy5I6o7nzzCxEw06P2rhzp1hIqkaab1kHySU7g dkpjmQ7Jjlrf6KdMP87mC/Hx4+zgVCkTQCKkIxNE76Ff3O9uTvkWCspSh9J0qPYyCaVta2D1 Sq5HZ8WFcap71iVO1f2/FEHKJNz/YTSOS/W7dxJdXl2eoj3gYX2UZNfoaVv8OXKaWslZlgqN jSg9wsTv1K73AnQKt4fFhscN9YFxhtgD/SQuOldE5Ws4UlJoaFX/yCoJL3ky2kC0WFngzwRF Yo6u/KON/o28yyP+alYRMBrN0Dm60FuVSIFafSqXoJTIjSZ6olbEoT0u17Rag8BxnxryMrgR dkccq272MaSS0eOC9K2rtvxzddohRFPcy/8bkX+t2iukTDz75KSTKO+chce62Xxdg62dpkZX xK+HeDCZ7gRNZvAbDETr6XI63hPKi891GeZqvqQVYR8e+V2725w+H1iv3THiB1tx4L2bXZDI DtMKQ5D2RvCHNdPNcZeldEoJwKoA60yg6tuUquvsLvfCwtrmVI2rL2djYxRfGNmFMrUDN1Xq F3xozA91q3iZd9OYi9G+M/OA01husBdcIzj1hu0aL+MGg4Gqk6XwjoSxVd4YT41kTU7Kk+/I 5/Nf+i88ULt6HanBYcY/+Daeo/XFABEBAAGJAjYEGAEIACAWIQT7om49ONNvHjv2jc5a3lvU aWv7pQUCWYoE5AIbDAAKCRBa3lvUaWv7pfmcEACKTRQ28b1y5ztKuLdLr79+T+LwZKHjX++P 4wKjEOECCcB6KCv3hP+J2GCXDOPZvdg/ZYZafqP68Yy8AZqkfa4qPYHmIdpODtRzZSL48kM8 LRzV8Rl7J3ItvzdBRxf4T/Zseu5U6ELiQdCUkPGsJcPIJkgPjO2ROG/ZtYa9DvnShNWPlp+R uPwPccEQPWO/NP4fJl2zwC6byjljZhW5kxYswGMLBwb5cDUZAisIukyAa8Xshdan6C2RZcNs rB3L7vsg/R8UCehxOH0C+NypG2GqjVejNZsc7bgV49EOVltS+GmGyY+moIzxsuLmT93rqyII 5rSbbcTLe6KBYcs24XEoo49Zm9oDA3jYvNpeYD8rDcnNbuZh9kTgBwFN41JHOPv0W2FEEWqe JsCwQdcOQ56rtezdCJUYmRAt3BsfjN3Jn3N6rpodi4Dkdli8HylM5iq4ooeb5VkQ7UZxbCWt UVMKkOCdFhutRmYp0mbv2e87IK4erwNHQRkHUkzbsuym8RVpAZbLzLPIYK/J3RTErL6Z99N2 m3J6pjwSJY/zNwuFPs9zGEnRO4g0BUbwGdbuvDzaq6/3OJLKohr5eLXNU3JkT+3HezydWm3W OPhauth7W0db74Qd49HXK0xe/aPrK+Cp+kU1HRactyNtF8jZQbhMCC8vMGukZtWaAwpjWiiH bA== Subject: Re: [PATCH] block: reexpand iov_iter after read/write Message-ID: Date: Tue, 6 Apr 2021 12:04:49 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <3bd14a60-b259-377b-38d5-907780bc2416@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 06/04/2021 02:28, yangerkun wrote: > Ping... It wasn't forgotten, but wouln't have worked because of other reasons. With these two already queued, that's a different story. https://git.kernel.dk/cgit/linux-block/commit/?h=io_uring-5.12&id=07204f21577a1d882f0259590c3553fe6a476381 https://git.kernel.dk/cgit/linux-block/commit/?h=io_uring-5.12&id=230d50d448acb6639991440913299e50cacf1daf Can you re-confirm, that the bug is still there (should be) and your patch fixes it? > > 在 2021/4/1 15:18, yangerkun 写道: >> We get a bug: >> >> BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x11c/0x404 >> lib/iov_iter.c:1139 >> Read of size 8 at addr ffff0000d3fb11f8 by task >> >> CPU: 0 PID: 12582 Comm: syz-executor.2 Not tainted >> 5.10.0-00843-g352c8610ccd2 #2 >> Hardware name: linux,dummy-virt (DT) >> Call trace: >>   dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132 >>   show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196 >>   __dump_stack lib/dump_stack.c:77 [inline] >>   dump_stack+0x110/0x164 lib/dump_stack.c:118 >>   print_address_description+0x78/0x5c8 mm/kasan/report.c:385 >>   __kasan_report mm/kasan/report.c:545 [inline] >>   kasan_report+0x148/0x1e4 mm/kasan/report.c:562 >>   check_memory_region_inline mm/kasan/generic.c:183 [inline] >>   __asan_load8+0xb4/0xbc mm/kasan/generic.c:252 >>   iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139 >>   io_read fs/io_uring.c:3421 [inline] >>   io_issue_sqe+0x2344/0x2d64 fs/io_uring.c:5943 >>   __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 >>   io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 >>   io_submit_sqe fs/io_uring.c:6395 [inline] >>   io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 >>   __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] >>   __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] >>   __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 >>   __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] >>   invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] >>   el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] >>   do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 >>   el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 >>   el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 >>   el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 >> >> Allocated by task 12570: >>   stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 >>   kasan_save_stack mm/kasan/common.c:48 [inline] >>   kasan_set_track mm/kasan/common.c:56 [inline] >>   __kasan_kmalloc+0xdc/0x120 mm/kasan/common.c:461 >>   kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475 >>   __kmalloc+0x23c/0x334 mm/slub.c:3970 >>   kmalloc include/linux/slab.h:557 [inline] >>   __io_alloc_async_data+0x68/0x9c fs/io_uring.c:3210 >>   io_setup_async_rw fs/io_uring.c:3229 [inline] >>   io_read fs/io_uring.c:3436 [inline] >>   io_issue_sqe+0x2954/0x2d64 fs/io_uring.c:5943 >>   __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 >>   io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 >>   io_submit_sqe fs/io_uring.c:6395 [inline] >>   io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 >>   __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] >>   __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] >>   __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 >>   __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] >>   invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] >>   el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] >>   do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 >>   el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 >>   el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 >>   el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 >> >> Freed by task 12570: >>   stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 >>   kasan_save_stack mm/kasan/common.c:48 [inline] >>   kasan_set_track+0x38/0x6c mm/kasan/common.c:56 >>   kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355 >>   __kasan_slab_free+0x124/0x150 mm/kasan/common.c:422 >>   kasan_slab_free+0x10/0x1c mm/kasan/common.c:431 >>   slab_free_hook mm/slub.c:1544 [inline] >>   slab_free_freelist_hook mm/slub.c:1577 [inline] >>   slab_free mm/slub.c:3142 [inline] >>   kfree+0x104/0x38c mm/slub.c:4124 >>   io_dismantle_req fs/io_uring.c:1855 [inline] >>   __io_free_req+0x70/0x254 fs/io_uring.c:1867 >>   io_put_req_find_next fs/io_uring.c:2173 [inline] >>   __io_queue_sqe+0x1fc/0x520 fs/io_uring.c:6279 >>   __io_req_task_submit+0x154/0x21c fs/io_uring.c:2051 >>   io_req_task_submit+0x2c/0x44 fs/io_uring.c:2063 >>   task_work_run+0xdc/0x128 kernel/task_work.c:151 >>   get_signal+0x6f8/0x980 kernel/signal.c:2562 >>   do_signal+0x108/0x3a4 arch/arm64/kernel/signal.c:658 >>   do_notify_resume+0xbc/0x25c arch/arm64/kernel/signal.c:722 >>   work_pending+0xc/0x180 >> >> blkdev_read_iter can truncate iov_iter's count since the count + pos may >> exceed the size of the blkdev. This will confuse io_read that we have >> consume the iovec. And once we do the iov_iter_revert in io_read, we >> will trigger the slab-out-of-bounds. Fix it by reexpand the count with >> size has been truncated. >> >> blkdev_write_iter can trigger the problem too. >> >> Signed-off-by: yangerkun >> --- >>   fs/block_dev.c | 20 +++++++++++++++++--- >>   1 file changed, 17 insertions(+), 3 deletions(-) >> >> diff --git a/fs/block_dev.c b/fs/block_dev.c >> index 92ed7d5df677..788e1014576f 100644 >> --- a/fs/block_dev.c >> +++ b/fs/block_dev.c >> @@ -1680,6 +1680,7 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) >>       struct inode *bd_inode = bdev_file_inode(file); >>       loff_t size = i_size_read(bd_inode); >>       struct blk_plug plug; >> +    size_t shorted = 0; >>       ssize_t ret; >>         if (bdev_read_only(I_BDEV(bd_inode))) >> @@ -1697,12 +1698,17 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) >>       if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT) >>           return -EOPNOTSUPP; >>   -    iov_iter_truncate(from, size - iocb->ki_pos); >> +    size -= iocb->ki_pos; >> +    if (iov_iter_count(from) > size) { >> +        shorted = iov_iter_count(from) - size; >> +        iov_iter_truncate(from, size); >> +    } >>         blk_start_plug(&plug); >>       ret = __generic_file_write_iter(iocb, from); >>       if (ret > 0) >>           ret = generic_write_sync(iocb, ret); >> +    iov_iter_reexpand(from, iov_iter_count(from) + shorted); >>       blk_finish_plug(&plug); >>       return ret; >>   } >> @@ -1714,13 +1720,21 @@ ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) >>       struct inode *bd_inode = bdev_file_inode(file); >>       loff_t size = i_size_read(bd_inode); >>       loff_t pos = iocb->ki_pos; >> +    size_t shorted = 0; >> +    ssize_t ret; >>         if (pos >= size) >>           return 0; >>         size -= pos; >> -    iov_iter_truncate(to, size); >> -    return generic_file_read_iter(iocb, to); >> +    if (iov_iter_count(to) > size) { >> +        shorted = iov_iter_count(to) - size; >> +        iov_iter_truncate(to, size); >> +    } >> + >> +    ret = generic_file_read_iter(iocb, to); >> +    iov_iter_reexpand(to, iov_iter_count(to) + shorted); >> +    return ret; >>   } >>   EXPORT_SYMBOL_GPL(blkdev_read_iter); >>   -- Pavel Begunkov