syzbot


KFENCE: use-after-free in kvm_fastop_exception

Status: closed as dup on 2021/09/11 10:44
Reported-by: syzbot+7b938780d5deeaaf938f@syzkaller.appspotmail.com
First crash: 324d, last: 280d

Cause bisection: introduced by (bisect log) :
commit c4512c63b1193c73b3f09c598a6d0a7f88da1dd8
Author: Matthieu Baerts <matthieu.baerts@tessares.net>
Date: Fri Jun 25 21:25:22 2021 +0000

  mptcp: fix 'masking a bool' warning

Crash: BUG: sleeping function called from invalid context in lock_sock_nested (log)
Repro: C syz .config
Duplicate of (1):
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in __d_alloc (2) C unreliable 6774 280d 324d

Sample crash report:
==================================================================
BUG: KFENCE: use-after-free read in kvm_fastop_exception+0xf6a/0x1058

Use-after-free read at 0xffff88823bccc028 (in kfence-#101):
 kvm_fastop_exception+0xf6a/0x1058
 d_lookup+0xd8/0x170 fs/dcache.c:2370
 lookup_dcache+0x1e/0x130 fs/namei.c:1520
 __lookup_hash+0x29/0x180 fs/namei.c:1543
 kern_path_locked+0x17e/0x320 fs/namei.c:2567
 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

kfence-#101: 0xffff88823bccc000-0xffff88823bcccfff, size=4096, cache=names_cache

allocated by task 22 on cpu 1 at 267.954189s:
 getname_kernel+0x4e/0x370 fs/namei.c:226
 kern_path_locked+0x71/0x320 fs/namei.c:2558
 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

freed by task 22 on cpu 1 at 267.954207s:
 putname.part.0+0xe1/0x120 fs/namei.c:270
 putname include/linux/err.h:41 [inline]
 filename_parentat fs/namei.c:2547 [inline]
 kern_path_locked+0xc2/0x320 fs/namei.c:2558
 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kvm_fastop_exception+0xf6a/0x1058
Code: d3 ed e9 bf d9 6e f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 15 e7 6e f8 49 8d 4d 00 48 83 e1 f8 <4c> 8b 21 41 8d 4d 00 83 e1 07 c1 e1 03 49 d3 ec e9 05 f1 6e f8 bd
RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010286
RAX: 0000000000373230 RBX: ffff88806fed5c28 RCX: ffff88823bccc028
RDX: ffffed100dfdab8c RSI: 0000000000000003 RDI: 0000000000000007
RBP: 0000000000000003 R08: 0000000000000000 R09: ffff88806fed5c58
R10: ffffed100dfdab8b R11: 0000000000000000 R12: ffff88823bccc02c
R13: ffff88823bccc02c R14: ffff88806fed5c58 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88823bccc028 CR3: 000000007571e000 CR4: 0000000000350ee0
Call Trace:
 d_lookup+0xd8/0x170 fs/dcache.c:2370
 lookup_dcache+0x1e/0x130 fs/namei.c:1520
 __lookup_hash+0x29/0x180 fs/namei.c:1543
 kern_path_locked+0x17e/0x320 fs/namei.c:2567
 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
==================================================================
----------------
Code disassembly (best guess):
   0:	d3 ed                	shr    %cl,%ebp
   2:	e9 bf d9 6e f8       	jmpq   0xf86ed9c6
   7:	49 8d 0e             	lea    (%r14),%rcx
   a:	48 83 e1 f8          	and    $0xfffffffffffffff8,%rcx
   e:	4c 8b 21             	mov    (%rcx),%r12
  11:	41 8d 0e             	lea    (%r14),%ecx
  14:	83 e1 07             	and    $0x7,%ecx
  17:	c1 e1 03             	shl    $0x3,%ecx
  1a:	49 d3 ec             	shr    %cl,%r12
  1d:	e9 15 e7 6e f8       	jmpq   0xf86ee737
  22:	49 8d 4d 00          	lea    0x0(%r13),%rcx
  26:	48 83 e1 f8          	and    $0xfffffffffffffff8,%rcx
* 2a:	4c 8b 21             	mov    (%rcx),%r12 <-- trapping instruction
  2d:	41 8d 4d 00          	lea    0x0(%r13),%ecx
  31:	83 e1 07             	and    $0x7,%ecx
  34:	c1 e1 03             	shl    $0x3,%ecx
  37:	49 d3 ec             	shr    %cl,%r12
  3a:	e9 05 f1 6e f8       	jmpq   0xf86ef144
  3f:	bd                   	.byte 0xbd

Crashes (15107):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2021/09/12 20:38 upstream 78e709522d2c 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 15:38 upstream 78e709522d2c 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 03:52 upstream c605c39677b9 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 02:12 upstream c605c39677b9 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 01:49 upstream c605c39677b9 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-smack-root 2021/09/12 01:17 upstream c605c39677b9 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 00:27 upstream c605c39677b9 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/11 15:36 upstream 926de8c4326c 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/11 12:16 upstream 926de8c4326c 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/11 10:58 upstream 926de8c4326c 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-smack-root 2021/09/11 01:17 upstream bf9f243f23e6 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/10 14:47 upstream bf9f243f23e6 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/10 02:04 upstream a3fa7a101dcf e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-smack-root 2021/09/08 22:50 upstream ac08b1c68d1b e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/08 08:35 upstream a2b28235335f 064c9eb7 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/08 04:58 upstream a2b28235335f 064c9eb7 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-root 2021/09/08 03:34 upstream a2b28235335f 064c9eb7 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-386 2021/09/10 13:07 upstream bf9f243f23e6 5ae8508a .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/10 04:35 linux-next f7f581157d1c e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/10 02:10 linux-next f7f581157d1c e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/09 23:57 linux-next f7f581157d1c e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/09 18:41 linux-next f7f581157d1c e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/09 16:06 linux-next f7f581157d1c e2776ee4 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/08/16 22:01 linux-next b9011c7e671d 33c26cb7 .config log report syz C KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-root 2021/09/12 07:02 upstream c605c39677b9 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-selinux-root 2021/09/11 16:29 upstream 926de8c4326c 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-selinux-root 2021/09/10 19:12 upstream bf9f243f23e6 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-selinux-root 2021/09/10 05:10 upstream a3fa7a101dcf e2776ee4 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-selinux-root 2021/09/08 08:57 upstream a2b28235335f 064c9eb7 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/08 06:08 upstream a2b28235335f 064c9eb7 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-root 2021/09/08 00:47 upstream a2b28235335f 064c9eb7 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-386 2021/09/09 13:58 upstream 0f4b9289bad3 e2776ee4 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-this-kasan-gce 2021/09/13 17:00 net f4bb62e64c88 3ce60af8 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-this-kasan-gce 2021/09/13 03:40 net f11ee2ad25b2 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-this-kasan-gce 2021/09/13 02:14 net f11ee2ad25b2 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-this-kasan-gce 2021/09/10 21:08 net 20e100f52730 5ae8508a .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-next-kasan-gce 2021/09/14 17:42 bpf-next 14bef1ab3037 07e953c1 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-next-kasan-gce 2021/09/14 17:19 bpf-next 14bef1ab3037 07e953c1 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-kasan-gce 2021/09/10 07:02 net-next 626bf91a292e e2776ee4 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-next-kasan-gce 2021/09/09 20:18 bpf-next 006a5099fc18 e2776ee4 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-kasan-gce 2021/09/08 01:49 net-next 27151f177827 064c9eb7 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/09 06:25 linux-next 999569d59a0a e2776ee4 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/09/08 04:21 linux-next b2bb710d34d5 064c9eb7 .config log report syz KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce 2021/09/12 18:42 upstream 78e709522d2c 5ae8508a .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-selinux-root 2021/09/12 18:02 upstream 78e709522d2c 5ae8508a .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-smack-root 2021/09/12 16:03 upstream 78e709522d2c 5ae8508a .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-kasan-gce-386 2021/09/12 20:11 upstream 78e709522d2c 5ae8508a .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 21:31 bpf 79e2c3066675 d82cb927 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 18:30 bpf 79e2c3066675 d82cb927 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 17:01 bpf 79e2c3066675 d82cb927 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 15:10 bpf 79e2c3066675 d82cb927 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 13:06 bpf 79e2c3066675 d82cb927 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 10:01 bpf 2248c2fca9c2 78494d16 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 04:44 bpf 2248c2fca9c2 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/28 00:32 bpf 2248c2fca9c2 78494d16 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/27 22:46 bpf 2248c2fca9c2 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/27 13:28 bpf a3debf177f21 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/27 11:18 bpf a3debf177f21 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 23:44 bpf a3debf177f21 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 22:20 bpf a3debf177f21 78494d16 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 17:16 bpf a3debf177f21 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 15:39 bpf a3debf177f21 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 13:35 bpf a3debf177f21 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 06:29 bpf a3debf177f21 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/26 02:23 bpf a3debf177f21 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/25 19:33 bpf a3debf177f21 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/25 11:12 bpf 199715243f72 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/25 07:55 bpf 199715243f72 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/25 04:32 bpf 199715243f72 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/25 00:08 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 19:54 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 17:19 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 16:02 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 11:00 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 09:10 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/24 07:17 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 23:58 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 20:44 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 20:19 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 19:06 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 14:24 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 11:47 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 07:38 bpf 7c3a00911b3d 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/23 03:08 bpf 7c3a00911b3d 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/22 21:00 bpf bc23f7244817 8cac236e .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/22 18:38 bpf bc23f7244817 8cac236e .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/22 16:37 bpf bc23f7244817 169724fe .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/22 10:41 bpf bc23f7244817 169724fe .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/22 02:29 bpf bc23f7244817 169724fe .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/21 20:00 bpf bc23f7244817 169724fe .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/21 13:29 bpf bc23f7244817 169724fe .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/21 12:07 bpf bc23f7244817 169724fe .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-kasan-gce 2021/09/21 10:30 bpf bc23f7244817 af796c18 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-this-kasan-gce 2021/09/17 00:35 net 98dc68f8b0c2 aae492f2 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-bpf-next-kasan-gce 2021/09/18 08:14 bpf-next ca21a3e5edfd 70b76c1d .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-net-kasan-gce 2021/09/16 22:44 net-next 52583c8d8b12 aae492f2 .config log report KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/08/16 08:07 linux-next b9011c7e671d 2489ab88 .config log report info KFENCE: use-after-free in kvm_fastop_exception
ci-upstream-linux-next-kasan-gce-root 2021/08/16 08:02 linux-next b9011c7e671d 2489ab88 .config log report info KFENCE: use-after-free in kvm_fastop_exception