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=-2.2 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 1A924C04A6B for ; Wed, 8 May 2019 19:50:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE6AA21726 for ; Wed, 8 May 2019 19:50:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cseHpGBd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727344AbfEHTuv (ORCPT ); Wed, 8 May 2019 15:50:51 -0400 Received: from mail-pf1-f180.google.com ([209.85.210.180]:34502 "EHLO mail-pf1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726852AbfEHTuu (ORCPT ); Wed, 8 May 2019 15:50:50 -0400 Received: by mail-pf1-f180.google.com with SMTP id n19so10201pfa.1; Wed, 08 May 2019 12:50:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=sVzcVct3OhKIVO1uKbdc1BVq2xvg3RVVsgKGJi0AZW8=; b=cseHpGBdh55JU0T6FkwMyaK/8411GC0h1zdOplsKutTf4bk7JZhyO9CsxHxiyD1KL9 yio/FEmE7+eTB44MAbysqEFFglwKiikR0zUCT5K1zozDJZAG2qy/MRkGGGhgb819TmBA ktYWgDkQa8+DG2o4pBJlGoEVAVSi0jvQ846JfMFE7XILGOhnIm6+eE9xB4vmVicxaU/s oMlxwwLubEYT9vdupfBsMhB0Tw+zHFc2uEMImOljfYXOXan5gBjLLGg7/BqZ/+LObgFj //bqNPsRsS68h5ANIBEYHfvVe8KGuB6aFVPsk6kPtjH6EX0/zUv/IWqIzO796p6fN2xP 74/A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :mime-version:content-disposition:user-agent; bh=sVzcVct3OhKIVO1uKbdc1BVq2xvg3RVVsgKGJi0AZW8=; b=VB2kjGG7OBqedly1jygNNaiSey0LJhX7NFuWLsZeT3qM4k6b1LBCMc+YI8d2hOiTSY tQMxXkk2NdhUiUI2cyQg0VTotpDrxC0p1oTB7XG07U9S/Uy8Gw9rWdUxlIqs29u8IUcf a11+KSJ5RduihFcK2EaqTmWivV5B94Hec/fuzwCJ3CgvIEAaWKn8kKSXvry6Fd7iKNRq xs/kKM9cdpmrZUACmPsDgOjtt4wNWOn6kwY/qaoj+1z8Vlbr/doZNMyUnUAVhI7QUGdg 8wBOgsGZ9lk6ZHCMypwOr1lhh6L/mdyvDfjoNF42fS9YjSwZq60dC0d7N9LAEzuhMMbe wCsQ== X-Gm-Message-State: APjAAAX2sEaOo+uj65BCez9F/6NnWQ2RigkBU6NFfZu0fgamkrSLO/3x 2SiiYmzsGukj3cyklsA0Pfo= X-Google-Smtp-Source: APXvYqxuTkubfEktoXwttohtSOJZ0MD5Qai9wrYiyVgT8pcUPbAebRuzAlQ0cjf8yNKq6XwhET253Q== X-Received: by 2002:aa7:93ba:: with SMTP id x26mr32759120pff.238.1557345049723; Wed, 08 May 2019 12:50:49 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id t9sm18886814pgp.66.2019.05.08.12.50.48 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 May 2019 12:50:49 -0700 (PDT) Date: Wed, 8 May 2019 12:50:47 -0700 From: Guenter Roeck To: Paolo Valente Cc: Jens Axboe , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: use-after-free in bfq_idle_slice_timer() Message-ID: <20190508195047.GA28280@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi, we have seen the attached use-after-free in bfq_idle_slice_timer() while running reboot tests. The code in these tests includes all bfq patches up to and including commit eed47d19d936 ("block, bfq: fix use after free in bfq_bfqq_expire"). gdb points to the dereference of struct bfq_queue *bfqq in bfq_bfqq_budget_timeout(). My suspicion is that the cleanup path in bfq_put_queue() may not clear bfqd->in_service_queue, but I don't understand the code well enough to be sure. Any thoughts / comments ? Thanks, Guenter --- [ 25.307269] ================================================================== [ 25.314555] BUG: KASAN: use-after-free in bfq_idle_slice_timer+0x88/0x1d4 [ 25.321359] Read of size 8 at addr fffffff089360440 by task swapper/0/0 [ 25.327975] [ 25.329487] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G S 4.19.38 #37 [ 25.336974] Hardware name: <...> rev2 board (DT) [ 25.342378] Call trace: [ 25.344844] dump_backtrace+0x0/0x358 [ 25.348521] show_stack+0x20/0x2c [ 25.351849] dump_stack+0x130/0x19c [ 25.355353] print_address_description+0x74/0x250 [ 25.360068] kasan_report+0x27c/0x2a0 [ 25.363742] __asan_report_load8_noabort+0x2c/0x38 [ 25.368546] bfq_idle_slice_timer+0x88/0x1d4 [ 25.372829] __hrtimer_run_queues+0x794/0xa34 [ 25.377197] hrtimer_interrupt+0x278/0x600 [ 25.381310] arch_timer_handler_phys+0x5c/0x6c [ 25.385767] handle_percpu_devid_irq+0x2e4/0x754 [ 25.390399] __handle_domain_irq+0xd4/0x158 [ 25.394593] gic_handle_irq+0x208/0x260 [ 25.398437] el1_irq+0xb0/0x128 [ 25.401591] arch_cpu_idle+0x20c/0x548 [ 25.405352] do_idle+0x184/0x4dc [ 25.408590] cpu_startup_entry+0x24/0x28 [ 25.412526] rest_init+0x114/0x148 [ 25.415939] start_kernel+0x4c8/0x5c4 [ 25.419605] [ 25.421105] Allocated by task 1430: [ 25.424606] kasan_kmalloc+0xe0/0x1ac [ 25.428279] kasan_slab_alloc+0x14/0x1c [ 25.432127] kmem_cache_alloc+0x178/0x278 [ 25.436149] bfq_get_queue+0x160/0x650 [ 25.439911] bfq_get_bfqq_handle_split+0xcc/0x2fc [ 25.444627] bfq_init_rq+0x254/0x18c0 [ 25.448301] bfq_insert_requests+0x5d0/0x1048 [ 25.452669] blk_mq_sched_insert_requests+0x130/0x204 [ 25.457734] blk_mq_flush_plug_list+0x844/0x91c [ 25.462278] blk_flush_plug_list+0x3e4/0x778 [ 25.466559] blk_finish_plug+0x54/0x78 [ 25.470322] read_pages+0x294/0x2f0 [ 25.473824] __do_page_cache_readahead+0x1a4/0x354 [ 25.478628] filemap_fault+0x8ec/0xbb4 [ 25.482389] ext4_filemap_fault+0x84/0xa4 [ 25.486409] __do_fault+0x128/0x338 [ 25.489909] handle_mm_fault+0x1de0/0x2588 [ 25.494017] do_page_fault+0x464/0x8d8 [ 25.497777] do_translation_fault+0x6c/0x88 [ 25.501969] do_mem_abort+0xd8/0x2d0 [ 25.505554] do_el0_ia_bp_hardening+0x13c/0x1a8 [ 25.510094] el0_ia+0x18/0x1c [ 25.513065] [ 25.514562] Freed by task 1430: [ 25.517715] __kasan_slab_free+0x13c/0x21c [ 25.521821] kasan_slab_free+0x10/0x1c [ 25.525582] kmem_cache_free+0x7c/0x5f8 [ 25.529429] bfq_put_queue+0x19c/0x2e4 [ 25.533191] bfq_exit_icq_bfqq+0x108/0x228 [ 25.537299] bfq_exit_icq+0x20/0x38 [ 25.540798] ioc_exit_icq+0xe4/0x16c [ 25.544384] put_io_context_active+0x174/0x234 [ 25.548836] exit_io_context+0x84/0x94 [ 25.552599] do_exit+0x13b4/0x18e4 [ 25.556013] do_group_exit+0x1cc/0x204 [ 25.559775] __wake_up_parent+0x0/0x5c [ 25.563537] __se_sys_exit_group+0x0/0x24 [ 25.567558] el0_svc_common+0x124/0x1ec [ 25.571407] el0_svc_compat_handler+0x84/0xb0 [ 25.575774] el0_svc_compat+0x8/0x18 [ 25.579351] [ 25.580854] The buggy address belongs to the object at fffffff089360338 [ 25.580854] which belongs to the cache bfq_queue of size 464 [ 25.587350] cros-ec-spi spi2.0: SPI transfer timed out [ 25.593209] The buggy address is located 264 bytes inside of [ 25.593209] 464-byte region [fffffff089360338, fffffff089360508) [ 25.593216] The buggy address belongs to the page: [ 25.593234] page:ffffffbfc224d800 count:1 mapcount:0 mapping:fffffff09916d880 index:0xfffffff089360cc8 [ 25.598388] cros-ec-spi spi2.0: spi transfer failed: -110 [ 25.610092] compound_mapcount: 0 [ 25.610109] flags: 0x4000000000008100(slab|head) [ 25.610133] raw: 4000000000008100 ffffffbfc14c1908 fffffff0991668a0 fffffff09916d880 [ 25.615021] cros-ec-spi spi2.0: Command xfer error (err:-110) [ 25.624225] raw: fffffff089360cc8 000000000014000d 00000001ffffffff 0000000000000000 [ 25.624233] page dumped because: kasan: bad access detected [ 25.624237] [ 25.624243] Memory state around the buggy address: [ 25.624257] fffffff089360300: fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb fb [ 25.624271] fffffff089360380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.630223] cros-ec-i2c-tunnel 11012000.spi:ec@0:i2c-tunnel: Error transferring EC i2c message -110 [ 25.632977] >fffffff089360400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.632985] ^ [ 25.632997] fffffff089360480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.633010] fffffff089360500: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.633016] ==================================================================