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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 A5852C432BE for ; Thu, 19 Aug 2021 10:04:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 88E6661139 for ; Thu, 19 Aug 2021 10:04:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237700AbhHSKEm (ORCPT ); Thu, 19 Aug 2021 06:04:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237743AbhHSKEl (ORCPT ); Thu, 19 Aug 2021 06:04:41 -0400 Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B276C061575; Thu, 19 Aug 2021 03:04:05 -0700 (PDT) Received: by mail-wr1-x436.google.com with SMTP id v4so8139599wro.12; Thu, 19 Aug 2021 03:04:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=b/caRtf32/S2/reVjg6DZxbLynBG2BkYEYoMEVU2wsU=; b=TQ9iY5pmpXThPWON0hCUKYF3EVTMvR7KwC0ROw8P8fvMskjpHGbdi6tWXQo+rOdwXH WhcGQeiaOCDuKlgEf1vIjXbu6D4GRRxIs+5QG58LAfl4958qBxjQgjHuJ89+quDKt3In pczN25jZfAmQinF9WRMo2TG/YEKv0j0/Mp0t+0OTEhcen7qVey8LdgDtFDeGMvhZnvD2 /uxapM2vGWSlin3md7AnNXhfuxrMxijJH62WSVW1F2a13ZDVVMS4Cuv8p2apk82xxJOK 0WBSotM1r+h4R4Xh2Z9lcuB1VpvEf4L8psYcP807MHZA5PcJPUjiRcuCm0QZvM7Jdy0G ryDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=b/caRtf32/S2/reVjg6DZxbLynBG2BkYEYoMEVU2wsU=; b=acEyWYYjjfVMmQgDAnnAJejPI48BAKeIye+WSJJpSyXNvM8cQbpyB+DJRwuLuTHTaW Kc6xFwe5Olhax7RBaNevBiZat3fUFuPxZIN1f/hMftlmCSK3wY9SqM5q9haAK5GgHOS8 xP2LMitijNdDp5QWWBzq2M1mo8AVP1Ap1b4JeZhzB7LPc/uolvZBVhWEz5E0YeCup8Fq dxzFzvXL+jzrXDy3dlM8YyJzXx0W9sJgGPo+UYkPJqsufV/l1biu98pXq89UaB+Ugl2v OtsQ2foBljgUG2blGpC1diM7Q601LX7NIhGx3AM6VThNtYeXMGTsK0wwd4ayNSPkB/k+ usKA== X-Gm-Message-State: AOAM533+gZaN7pF43oMTWL9ho8XGsoaUjnemqXCIddDgvRm4mM8oNnRY mRLzorXAHywuQWTSYy9nR7M= X-Google-Smtp-Source: ABdhPJxgsKEje8USaQPTlDcDYdO8wbVrthpYmO4v53wvoPZ6n7eg93vD6T1dkkv4TkLfHTxUNZ3wmg== X-Received: by 2002:adf:ab0e:: with SMTP id q14mr2802735wrc.171.1629367443969; Thu, 19 Aug 2021 03:04:03 -0700 (PDT) Received: from [192.168.8.197] ([185.69.145.21]) by smtp.gmail.com with ESMTPSA id n3sm6766119wms.2.2021.08.19.03.04.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Aug 2021 03:04:03 -0700 (PDT) Subject: Re: [syzbot] KASAN: use-after-free Read in tctx_task_work (2) To: syzbot , axboe@kernel.dk, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com References: <000000000000e1a5d005c9e514ed@google.com> From: Pavel Begunkov Message-ID: <858d47f0-48d5-fff5-24bb-346ebde4e127@gmail.com> Date: Thu, 19 Aug 2021 11:03:33 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <000000000000e1a5d005c9e514ed@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 8/19/21 9:10 AM, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: f26c3abc432a Add linux-next specific files for 20210818 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=169f1731300000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d472f8be79a62b44 > dashboard link: https://syzkaller.appspot.com/bug?extid=9c3492b27d10dc49ffa6 > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15f35e16300000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=161c1765300000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+9c3492b27d10dc49ffa6@syzkaller.appspotmail.com Can't find f26c3abc432a nor reproduce it. Let's try the latest branch. #syz test: git://git.kernel.dk/linux-block for-5.15/io_uring > ================================================================== > BUG: KASAN: use-after-free in ctx_flush_and_put fs/io_uring.c:2031 [inline] > BUG: KASAN: use-after-free in tctx_task_work+0x307/0x310 fs/io_uring.c:2078 > Read of size 4 at addr ffff88801da62358 by task syz-executor959/7251 > > CPU: 0 PID: 7251 Comm: syz-executor959 Not tainted 5.14.0-rc6-next-20210818-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 > print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256 > __kasan_report mm/kasan/report.c:442 [inline] > kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 > ctx_flush_and_put fs/io_uring.c:2031 [inline] > tctx_task_work+0x307/0x310 fs/io_uring.c:2078 > task_work_run+0xdd/0x1a0 kernel/task_work.c:164 > exit_task_work include/linux/task_work.h:32 [inline] > do_exit+0xbae/0x2a30 kernel/exit.c:825 > do_group_exit+0x129/0x310 kernel/exit.c:922 > get_signal+0x482/0x2170 kernel/signal.c:2846 > arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 > handle_signal_work kernel/entry/common.c:148 [inline] > exit_to_user_mode_loop kernel/entry/common.c:172 [inline] > exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 > __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] > syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 > do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x446749 > Code: Unable to access opcode bytes at RIP 0x44671f. > RSP: 002b:00007f2e177871e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa > RAX: 000000000000039b RBX: 00000000004cb468 RCX: 0000000000446749 > RDX: 0000000000000000 RSI: 0000000000006b46 RDI: 0000000000000006 > RBP: 00000000004cb460 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb46c > R13: 00007ffe292df50f R14: 00007f2e17787300 R15: 0000000000022000 > > Allocated by task 7251: > kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 > kasan_set_track mm/kasan/common.c:46 [inline] > set_alloc_info mm/kasan/common.c:434 [inline] > ____kasan_kmalloc mm/kasan/common.c:513 [inline] > ____kasan_kmalloc mm/kasan/common.c:472 [inline] > __kasan_kmalloc+0x9f/0xd0 mm/kasan/common.c:522 > kmalloc include/linux/slab.h:591 [inline] > kzalloc include/linux/slab.h:721 [inline] > io_ring_ctx_alloc fs/io_uring.c:1235 [inline] > io_uring_create fs/io_uring.c:9876 [inline] > io_uring_setup+0x27d/0x2d00 fs/io_uring.c:9982 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > Freed by task 6731: > kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 > kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 > kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 > ____kasan_slab_free mm/kasan/common.c:366 [inline] > ____kasan_slab_free mm/kasan/common.c:328 [inline] > __kasan_slab_free+0xff/0x140 mm/kasan/common.c:374 > kasan_slab_free include/linux/kasan.h:230 [inline] > slab_free_hook mm/slub.c:1681 [inline] > slab_free_freelist_hook+0x82/0x190 mm/slub.c:1706 > slab_free mm/slub.c:3463 [inline] > kfree+0xea/0x540 mm/slub.c:4523 > io_ring_ctx_free fs/io_uring.c:8902 [inline] > io_ring_exit_work+0x13c7/0x1940 fs/io_uring.c:9051 > process_one_work+0x9c9/0x16b0 kernel/workqueue.c:2297 > worker_thread+0x65b/0x1200 kernel/workqueue.c:2444 > kthread+0x3e5/0x4d0 kernel/kthread.c:319 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > > Last potentially related work creation: > kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 > kasan_record_aux_stack+0xe9/0x110 mm/kasan/generic.c:348 > insert_work+0x48/0x370 kernel/workqueue.c:1353 > __queue_work+0x5d1/0xf30 kernel/workqueue.c:1519 > queue_work_on+0xf6/0x110 kernel/workqueue.c:1546 > queue_work include/linux/workqueue.h:502 [inline] > io_ring_ctx_wait_and_kill+0x314/0x3d0 fs/io_uring.c:9104 > io_uring_release+0x3e/0x50 fs/io_uring.c:9112 > __fput+0x288/0x9f0 fs/file_table.c:280 > task_work_run+0xdd/0x1a0 kernel/task_work.c:164 > exit_task_work include/linux/task_work.h:32 [inline] > do_exit+0xbae/0x2a30 kernel/exit.c:825 > do_group_exit+0x129/0x310 kernel/exit.c:922 > get_signal+0x482/0x2170 kernel/signal.c:2846 > arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 > handle_signal_work kernel/entry/common.c:148 [inline] > exit_to_user_mode_loop kernel/entry/common.c:172 [inline] > exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 > __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] > syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 > do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > The buggy address belongs to the object at ffff88801da62000 > which belongs to the cache kmalloc-4k of size 4096 > The buggy address is located 856 bytes inside of > 4096-byte region [ffff88801da62000, ffff88801da63000) > The buggy address belongs to the page: > page:ffffea0000769800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1da60 > head:ffffea0000769800 order:3 compound_mapcount:0 compound_pincount:0 > flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) > raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c42140 > raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 254, ts 8722226076, free_ts 8721850730 > prep_new_page mm/page_alloc.c:2424 [inline] > get_page_from_freelist+0xa76/0x2f90 mm/page_alloc.c:4151 > __alloc_pages+0x1ba/0x510 mm/page_alloc.c:5373 > alloc_pages+0x1a7/0x300 mm/mempolicy.c:2188 > alloc_slab_page mm/slub.c:1744 [inline] > allocate_slab mm/slub.c:1881 [inline] > new_slab+0x321/0x490 mm/slub.c:1944 > ___slab_alloc+0x90b/0xfb0 mm/slub.c:2974 > __slab_alloc.constprop.0+0x51/0xa0 mm/slub.c:3061 > slab_alloc_node mm/slub.c:3152 [inline] > slab_alloc mm/slub.c:3194 [inline] > kmem_cache_alloc_trace+0x30a/0x3c0 mm/slub.c:3211 > kmalloc include/linux/slab.h:591 [inline] > kzalloc include/linux/slab.h:721 [inline] > kobject_uevent_env+0x240/0x1650 lib/kobject_uevent.c:524 > device_add+0xbc6/0x21b0 drivers/base/core.c:3340 > scsi_target_add drivers/scsi/scsi_sysfs.c:1309 [inline] > scsi_sysfs_add_sdev+0x464/0x750 drivers/scsi/scsi_sysfs.c:1336 > scsi_sysfs_add_devices drivers/scsi/scsi_scan.c:1727 [inline] > scsi_finish_async_scan drivers/scsi/scsi_scan.c:1812 [inline] > do_scan_async+0x211/0x500 drivers/scsi/scsi_scan.c:1855 > async_run_entry_fn+0x9d/0x550 kernel/async.c:127 > process_one_work+0x9c9/0x16b0 kernel/workqueue.c:2297 > worker_thread+0x65b/0x1200 kernel/workqueue.c:2444 > kthread+0x3e5/0x4d0 kernel/kthread.c:319 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > page last free stack trace: > reset_page_owner include/linux/page_owner.h:24 [inline] > free_pages_prepare mm/page_alloc.c:1338 [inline] > free_pcp_prepare+0x377/0x860 mm/page_alloc.c:1389 > free_unref_page_prepare mm/page_alloc.c:3315 [inline] > free_unref_page+0x19/0x690 mm/page_alloc.c:3394 > sbitmap_free include/linux/sbitmap.h:165 [inline] > scsi_device_dev_release_usercontext+0x65a/0xd60 drivers/scsi/scsi_sysfs.c:479 > execute_in_process_context+0x37/0x160 kernel/workqueue.c:3358 > device_release+0xa3/0x240 drivers/base/core.c:2195 > kobject_cleanup lib/kobject.c:705 [inline] > kobject_release lib/kobject.c:736 [inline] > kref_put include/linux/kref.h:65 [inline] > kobject_put+0x1d0/0x540 lib/kobject.c:753 > put_device+0x1b/0x30 drivers/base/core.c:3466 > __scsi_remove_device+0x1e1/0x3e0 drivers/scsi/scsi_sysfs.c:1477 > scsi_probe_and_add_lun+0x266d/0x35a0 drivers/scsi/scsi_scan.c:1205 > __scsi_scan_target+0x229/0xdc0 drivers/scsi/scsi_scan.c:1588 > scsi_scan_channel drivers/scsi/scsi_scan.c:1676 [inline] > scsi_scan_channel+0x148/0x1e0 drivers/scsi/scsi_scan.c:1652 > scsi_scan_host_selected+0x2df/0x3b0 drivers/scsi/scsi_scan.c:1705 > do_scsi_scan_host+0x1eb/0x260 drivers/scsi/scsi_scan.c:1844 > do_scan_async+0x3e/0x500 drivers/scsi/scsi_scan.c:1854 > async_run_entry_fn+0x9d/0x550 kernel/async.c:127 > process_one_work+0x9c9/0x16b0 kernel/workqueue.c:2297 > > Memory state around the buggy address: > ffff88801da62200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88801da62280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> ffff88801da62300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff88801da62380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88801da62400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches > -- Pavel Begunkov