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=-0.7 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 D6FEFC46464 for ; Fri, 10 Aug 2018 13:06:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E5B1223A9 for ; Fri, 10 Aug 2018 13:06:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E5B1223A9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728144AbeHJPfy (ORCPT ); Fri, 10 Aug 2018 11:35:54 -0400 Received: from mail-it0-f70.google.com ([209.85.214.70]:37822 "EHLO mail-it0-f70.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727539AbeHJPfy (ORCPT ); Fri, 10 Aug 2018 11:35:54 -0400 Received: by mail-it0-f70.google.com with SMTP id n144-v6so1926306itg.2 for ; Fri, 10 Aug 2018 06:06:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=NfCyzNzyvFztrsf8UBOi/f7szKGOKZ0oixK+PgGD0jI=; b=R8w8g+FuFlkF/Qx7C4+LHW71c6+NfF4hyNGSNXJijMoCC6d1sQp0V8/jd0v48gzmCU nqnveZu+OW16HhBAJ8PNUY3XUrKnnq08vwx6ONm/8oV4xIiRzv3ewyF/xnhFrud0exLk 8KTM/5hPIwwrykZhlNl9LJD3MojvIwqprdPAqxcGR2X9psylm6zOF0JJxN8ze2Il5gI7 ce0PF+wC6yhDFmp5ezCsljz5VUgHhpvo6Vrd/rvJ6HuCcxy5pGUx60qnmhrlbet2HWrC pXql65qkL/MRZZo5XiN5TKw64X988K5T15MNpacYRPJq7eFMurWYvcHmpj+NBUJM7rNn hJjw== X-Gm-Message-State: AOUpUlEPmRy/lJbA3qzLtHB6YcQe5yKXmJrxqFnIRetzbtZ4jv9P9sEO qYNMX8pb50AfxM+nZXXRAMXpL/nRBtgCwfI+J/cOPZ2E/o/7 X-Google-Smtp-Source: AA+uWPwJZHoeE7QwFHj8wtgRrq4k5Q/lTWjJFR61bO5Cxm0cyv2N/MNcsnAwPvVel2PGFqyDU7JEsBOJKjkLCTDIEJ9/oArk5Cpf MIME-Version: 1.0 X-Received: by 2002:a6b:3042:: with SMTP id w63-v6mr2625389iow.5.1533906362890; Fri, 10 Aug 2018 06:06:02 -0700 (PDT) Date: Fri, 10 Aug 2018 06:06:02 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e106310573146798@google.com> Subject: KASAN: use-after-free Read in finish_task_switch From: syzbot To: akpm@linux-foundation.org, dan.j.williams@intel.com, jglisse@redhat.com, jrdr.linux@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.com, minchan@kernel.org, riel@surriel.com, sfr@canb.auug.org.au, syzkaller-bugs@googlegroups.com, ying.huang@intel.com, zwisler@kernel.org Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 8c8399e0a3fb Add linux-next specific files for 20180806 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=173d8672400000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b6bc1781e49e93e dashboard link: https://syzkaller.appspot.com/bug?extid=e62f8ba2b2af8dbd6729 compiler: gcc (GCC) 8.0.1 20180413 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+e62f8ba2b2af8dbd6729@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in __fire_sched_in_preempt_notifiers kernel/sched/core.c:2481 [inline] BUG: KASAN: use-after-free in fire_sched_in_preempt_notifiers kernel/sched/core.c:2487 [inline] BUG: KASAN: use-after-free in finish_task_switch+0x544/0x870 kernel/sched/core.c:2679 Read of size 8 at addr ffff880193b21d18 by task syz-executor3/4885 CPU: 0 PID: 4885 Comm: syz-executor3 Not tainted 4.18.0-rc8-next-20180806+ #32 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __fire_sched_in_preempt_notifiers kernel/sched/core.c:2481 [inline] fire_sched_in_preempt_notifiers kernel/sched/core.c:2487 [inline] finish_task_switch+0x544/0x870 kernel/sched/core.c:2679 context_switch kernel/sched/core.c:2826 [inline] __schedule+0x884/0x1ec0 kernel/sched/core.c:3471 preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3595 _cond_resched+0x1d/0x30 kernel/sched/core.c:4961 zap_pmd_range mm/memory.c:1449 [inline] zap_pud_range mm/memory.c:1476 [inline] zap_p4d_range mm/memory.c:1497 [inline] unmap_page_range+0x11d2/0x2100 mm/memory.c:1518 unmap_single_vma+0x1a0/0x310 mm/memory.c:1563 unmap_vmas+0x125/0x200 mm/memory.c:1593 exit_mmap+0x2c2/0x590 mm/mmap.c:3093 __mmput kernel/fork.c:1003 [inline] mmput+0x265/0x620 kernel/fork.c:1024 exit_mm kernel/exit.c:544 [inline] do_exit+0xec6/0x2760 kernel/exit.c:856 do_group_exit+0x177/0x440 kernel/exit.c:972 get_signal+0x88e/0x1970 kernel/signal.c:2467 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456cb9 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f24f212ecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000009300a8 RCX: 0000000000456cb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000009300a8 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000009300ac R13: 00007ffe23b48b7f R14: 00007f24f212f9c0 R15: 0000000000000000 Allocated by task 4885: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 kmem_cache_zalloc include/linux/slab.h:697 [inline] vmx_create_vcpu+0xcf/0x2980 arch/x86/kvm/vmx.c:10656 kvm_arch_vcpu_create+0xe5/0x220 arch/x86/kvm/x86.c:8398 kvm_vm_ioctl_create_vcpu arch/x86/kvm/../../../virt/kvm/kvm_main.c:2476 [inline] kvm_vm_ioctl+0x488/0x1d80 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2977 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4884: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x2d0 mm/slab.c:3756 vmx_free_vcpu+0x26b/0x300 arch/x86/kvm/vmx.c:10650 kvm_arch_vcpu_free arch/x86/kvm/x86.c:8384 [inline] kvm_free_vcpus arch/x86/kvm/x86.c:8833 [inline] kvm_arch_destroy_vm+0x365/0x7c0 arch/x86/kvm/x86.c:8930 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:752 [inline] kvm_put_kvm+0x73f/0x1060 arch/x86/kvm/../../../virt/kvm/kvm_main.c:773 kvm_vcpu_release+0x7b/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2407 __fput+0x376/0x8a0 fs/file_table.c:279 ____fput+0x15/0x20 fs/file_table.c:312 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff880193b21d00 which belongs to the cache kvm_vcpu of size 23808 The buggy address is located 24 bytes inside of 23808-byte region [ffff880193b21d00, ffff880193b27a00) The buggy address belongs to the page: page:ffffea00064ec800 count:1 mapcount:0 mapping:ffff8801d4c35dc0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea000657de08 ffff8801d4c29648 ffff8801d4c35dc0 raw: 0000000000000000 ffff880193b21d00 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880193b21c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff880193b21c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff880193b21d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff880193b21d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880193b21e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This bug is generated by a bot. 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