syzbot


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

Status: upstream: reported C repro on 2019/11/07 21:27
Reported-by: syzbot+14b70ff3ebb853f8c5bb@syzkaller.appspotmail.com
First crash: 1010d, last: 360d

Cause bisection: introduced by (bisect log) :
commit a107bf8b3905b61bf8b5c181268bca8c05af7f69
Author: Mike Rapoport <rppt@linux.vnet.ibm.com>
Date: Wed Nov 30 07:52:01 2016 +0000

  isofs: add KERN_CONT to printing of ER records

Crash: no output from test machine (log)
Repro: C syz .config

Fix bisection: failed (bisect log)
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 kernel BUG at arch/x86/kvm/mmu.c:LINE! C done inconclusive 4 740d 1010d 0/1 upstream: reported C repro on 2019/11/07 23:54
upstream kernel BUG at arch/x86/kvm/mmu.c:LINE! C 695 1629d 1746d 4/23 fixed on 2018/03/06 13:29
upstream kernel BUG at arch/x86/kvm/mmu.c:LINE! (2) C done 5 1004d 1009d 0/23 closed as dup on 2019/11/08 19:42

Sample crash report:
audit: type=1400 audit(1576181055.179:36): avc:  denied  { map } for  pid=7818 comm="syz-executor818" path="/root/syz-executor818897800" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
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.
audit: type=1400 audit(1576181055.179:37): avc:  denied  { map } for  pid=7818 comm="syz-executor818" path="socket:[30256]" dev="sockfs" ino=30256 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=socket permissive=1
------------[ cut here ]------------
kernel BUG at arch/x86/kvm/mmu.c:3279!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7818 Comm: syz-executor818 Not tainted 4.19.88-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:transparent_hugepage_adjust+0x4bb/0x540 arch/x86/kvm/mmu.c:3279
Code: ff ff e8 e8 05 5c 00 48 8b 45 b8 48 83 e8 01 48 89 45 c8 e9 a3 fd ff ff 48 89 df e8 1f 95 93 00 e9 88 fb ff ff e8 c5 05 5c 00 <0f> 0b 48 8b 7d c8 e8 0a 95 93 00 e9 ba fc ff ff 49 8d 7f 30 e8 dc
RSP: 0018:ffff88808ada7628 EFLAGS: 00010293
RAX: ffff88808e4b6500 RBX: ffff88808ada7718 RCX: ffffffff810f3c3a
RDX: 0000000000000000 RSI: ffffffff810f3d7b RDI: 0000000000000007
RBP: ffff88808ada7670 R08: ffff88808e4b6500 R09: ffffed100f2496c2
R10: ffffed100f2496c1 R11: ffff88807924b60b R12: 0000000000000183
R13: 00000000000a8783 R14: 00000000000a8781 R15: 0000000000000000
FS:  00000000008ce880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000008e4e5000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tdp_page_fault+0x580/0x6a0 arch/x86/kvm/mmu.c:4185
 kvm_mmu_page_fault+0x1b1/0x1600 arch/x86/kvm/mmu.c:5331
 handle_ept_violation+0x1d7/0x520 arch/x86/kvm/vmx.c:7689
 vmx_handle_exit+0x276/0x16b0 arch/x86/kvm/vmx.c:10175
 vcpu_enter_guest+0x10ca/0x5ed0 arch/x86/kvm/x86.c:7800
 vcpu_run arch/x86/kvm/x86.c:7863 [inline]
 kvm_arch_vcpu_ioctl_run+0x457/0x16b0 arch/x86/kvm/x86.c:8063
 kvm_vcpu_ioctl+0x4dc/0xf90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2667
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440359
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:00007ffcef50d9e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440359
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401be0
R13: 0000000000401c70 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 2877431f547122ff ]---
RIP: 0010:transparent_hugepage_adjust+0x4bb/0x540 arch/x86/kvm/mmu.c:3279
Code: ff ff e8 e8 05 5c 00 48 8b 45 b8 48 83 e8 01 48 89 45 c8 e9 a3 fd ff ff 48 89 df e8 1f 95 93 00 e9 88 fb ff ff e8 c5 05 5c 00 <0f> 0b 48 8b 7d c8 e8 0a 95 93 00 e9 ba fc ff ff 49 8d 7f 30 e8 dc
RSP: 0018:ffff88808ada7628 EFLAGS: 00010293
RAX: ffff88808e4b6500 RBX: ffff88808ada7718 RCX: ffffffff810f3c3a
RDX: 0000000000000000 RSI: ffffffff810f3d7b RDI: 0000000000000007
RBP: ffff88808ada7670 R08: ffff88808e4b6500 R09: ffffed100f2496c2
R10: ffffed100f2496c1 R11: ffff88807924b60b R12: 0000000000000183
R13: 00000000000a8783 R14: 00000000000a8781 R15: 0000000000000000
FS:  00000000008ce880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000008e4e5000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (12):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2019/12/12 20:07 linux-4.19.y fb683b5e3f53 08003f64 .config log report syz C
ci2-linux-4-19 2019/11/07 21:08 linux-4.19.y 5ee93551c703 f39aff9e .config log report syz C
ci2-linux-4-19 2021/08/18 11:55 linux-4.19.y 59456c9cc40c a2fe1cb5 .config log report info kernel BUG in transparent_hugepage_adjust
ci2-linux-4-19 2021/08/17 19:20 linux-4.19.y 59456c9cc40c a2fe1cb5 .config log report info kernel BUG in transparent_hugepage_adjust
ci2-linux-4-19 2020/08/16 20:03 linux-4.19.y c14d30dc9987 5ce13532 .config log report
ci2-linux-4-19 2020/08/15 09:23 linux-4.19.y c14d30dc9987 5ce13532 .config log report
ci2-linux-4-19 2020/05/25 19:38 linux-4.19.y 1bab61d3e8cd 73964a9b .config log report
ci2-linux-4-19 2020/05/25 19:38 linux-4.19.y 1bab61d3e8cd 73964a9b .config log report
ci2-linux-4-19 2020/05/25 19:37 linux-4.19.y 1bab61d3e8cd 73964a9b .config log report
ci2-linux-4-19 2020/05/25 19:29 linux-4.19.y 1bab61d3e8cd 73964a9b .config log report
ci2-linux-4-19 2020/05/25 19:29 linux-4.19.y 1bab61d3e8cd 73964a9b .config log report
ci2-linux-4-19 2019/11/07 20:26 linux-4.19.y 5ee93551c703 f39aff9e .config log report