syzbot


kernel BUG at arch/x86/kvm/mmu/mmu.c:LINE! (2)

Status: fixed on 2020/07/17 17:58
Subsystems: kvm
[Documentation on labels]
Reported-by: syzbot+904752567107eefb728c@syzkaller.appspotmail.com
Fix commit: 7d2e8748af62 KVM: x86: Initialize tdp_level during vCPU creation
First crash: 1488d, last: 1452d
Cause bisection: introduced by (bisect log) :
commit 63d04348371b7ea4a134bcf47c79763d969e9168
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue Mar 31 22:42:22 2020 +0000

  KVM: x86: move kvm_create_vcpu_debugfs after last failure point

Crash: general protection fault in start_creating (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] KVM: x86: Initialize tdp_level during vCPU creation 13 (13) 2020/05/29 13:06
kernel BUG at arch/x86/kvm/mmu/mmu.c:LINE! (2) 1 (2) 2020/05/27 00:12
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG at arch/x86/kvm/mmu/mmu.c:LINE! kvm C done 6 1638d 1646d 15/27 fixed on 2020/02/18 14:31

Sample crash report:
L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
------------[ cut here ]------------
kernel BUG at arch/x86/kvm/mmu/mmu.c:3719!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 6780 Comm: syz-executor756 Not tainted 5.7.0-rc7-next-20200529-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mmu_alloc_direct_roots arch/x86/kvm/mmu/mmu.c:3719 [inline]
RIP: 0010:mmu_alloc_roots arch/x86/kvm/mmu/mmu.c:3819 [inline]
RIP: 0010:kvm_mmu_load+0xbfa/0xe00 arch/x86/kvm/mmu/mmu.c:5152
Code: ac 23 99 00 48 8b 44 24 08 e9 cf f5 ff ff e8 6d 23 99 00 e9 b7 f4 ff ff 4c 89 f7 e8 90 23 99 00 e9 78 f4 ff ff e8 56 1a 5a 00 <0f> 0b 48 89 df e8 7c 23 99 00 e9 7e f8 ff ff e8 72 23 99 00 e9 c4
RSP: 0018:ffffc90001477b30 EFLAGS: 00010293
RAX: ffff88808ba68400 RBX: 0000000000000000 RCX: ffffffff8118d661
RDX: 0000000000000000 RSI: ffffffff8118e14a RDI: 0000000000000001
RBP: ffff888089dfc040 R08: ffff88808ba68400 R09: ffffed1015ce719c
R10: ffff8880ae738cdb R11: ffffed1015ce719b R12: 0000000000000000
R13: 0000000000000001 R14: ffff888089dfc458 R15: 0000000000000000
FS:  00000000016b1880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2329d226c0 CR3: 000000009c2ee000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kvm_mmu_reload arch/x86/kvm/mmu.h:81 [inline]
 vcpu_enter_guest arch/x86/kvm/x86.c:8389 [inline]
 vcpu_run arch/x86/kvm/x86.c:8600 [inline]
 kvm_arch_vcpu_ioctl_run+0x4016/0x68d0 arch/x86/kvm/x86.c:8823
 kvm_vcpu_ioctl+0x467/0xe10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3147
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4401f9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffcb2f66848 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401f9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401a80
R13: 0000000000401b10 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 1fd83544911686e9 ]---
RIP: 0010:mmu_alloc_direct_roots arch/x86/kvm/mmu/mmu.c:3719 [inline]
RIP: 0010:mmu_alloc_roots arch/x86/kvm/mmu/mmu.c:3819 [inline]
RIP: 0010:kvm_mmu_load+0xbfa/0xe00 arch/x86/kvm/mmu/mmu.c:5152
Code: ac 23 99 00 48 8b 44 24 08 e9 cf f5 ff ff e8 6d 23 99 00 e9 b7 f4 ff ff 4c 89 f7 e8 90 23 99 00 e9 78 f4 ff ff e8 56 1a 5a 00 <0f> 0b 48 89 df e8 7c 23 99 00 e9 7e f8 ff ff e8 72 23 99 00 e9 c4
RSP: 0018:ffffc90001477b30 EFLAGS: 00010293
RAX: ffff88808ba68400 RBX: 0000000000000000 RCX: ffffffff8118d661
RDX: 0000000000000000 RSI: ffffffff8118e14a RDI: 0000000000000001
RBP: ffff888089dfc040 R08: ffff88808ba68400 R09: ffffed1015ce719c
R10: ffff8880ae738cdb R11: ffffed1015ce719b R12: 0000000000000000
R13: 0000000000000001 R14: ffff888089dfc458 R15: 0000000000000000
FS:  00000000016b1880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b1b454000 CR3: 000000009c2ee000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (46328):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/24 12:08 linux-next e7b08814b16b 54566aff .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/06/04 11:22 linux-next e7b08814b16b b0d1c0d5 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/05/31 06:57 linux-next e7b08814b16b 6f3e1c7c .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/05/25 21:37 linux-next 7b4cb0a48db0 30927cd7 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/05/25 04:23 linux-next c11d28ab4a69 11284182 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/05/22 23:20 linux-next c11d28ab4a69 9682898d .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/05/22 21:58 linux-next c11d28ab4a69 9682898d .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/06/27 03:07 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 02:57 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 02:48 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 02:38 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 02:26 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 02:10 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 01:51 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 01:42 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 01:31 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 01:06 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 00:52 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 00:42 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 00:28 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/27 00:15 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 23:56 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 23:42 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 23:27 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 23:11 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 22:59 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 22:43 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 22:24 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 22:09 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 21:53 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 21:39 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 21:28 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 21:15 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 21:01 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 20:45 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 20:32 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 20:14 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 19:57 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 19:41 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 19:29 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 19:17 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 19:05 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 18:49 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 18:35 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 18:22 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 18:10 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 17:54 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/06/26 17:31 linux-next e7b08814b16b aea82c00 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/05/22 15:26 linux-next c11d28ab4a69 9682898d .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.