R13: 000000000000000b R14: 00007fe340933f80 R15: 00007ffc6181a448
---[ end trace a71b37e892f8e741 ]---
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 435 Comm: syz-executor.0 Tainted: G        W         5.4.284-syzkaller-05001-g893d9dfc5bf5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:kill_device drivers/base/core.c:3028 [inline]
RIP: 0010:device_del+0xe7/0xfa0 drivers/base/core.c:3055
Code: df e8 7d ad fd fe 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 0f 85 31 0e 00 00 41 0f b6 1f 89 de 83 e6 01
RSP: 0018:ffff8881ef1bf9c0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881ef7260d8 RCX: 1ffff1103dee4c1b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ef1bf940
RBP: ffff8881ef1bfa90 R08: dffffc0000000000 R09: ffffed103de37f29
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000019
R13: ffff8881ef726070 R14: ffff8881ef726110 R15: 00000000000000c8
FS:  00007fe3403976c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a5c2a943b0 CR3: 00000001ef14f000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 del_gendisk+0x9d9/0xc30 block/genhd.c:835
 loop_remove+0x42/0xa0 drivers/block/loop.c:2194
 loop_control_ioctl+0x564/0x620 drivers/block/loop.c:2293
 do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
 ksys_ioctl fs/ioctl.c:742 [inline]
 __do_sys_ioctl fs/ioctl.c:749 [inline]
 __se_sys_ioctl fs/ioctl.c:747 [inline]
 __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fe340814859
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe3403970c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe340933f80 RCX: 00007fe340814859
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 00007fe340870ad0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe340933f80 R15: 00007ffc6181a448
Modules linked in:
---[ end trace a71b37e892f8e742 ]---
RIP: 0010:kill_device drivers/base/core.c:3028 [inline]
RIP: 0010:device_del+0xe7/0xfa0 drivers/base/core.c:3055
Code: df e8 7d ad fd fe 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 0f 85 31 0e 00 00 41 0f b6 1f 89 de 83 e6 01
RSP: 0018:ffff8881ef1bf9c0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881ef7260d8 RCX: 1ffff1103dee4c1b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ef1bf940
RBP: ffff8881ef1bfa90 R08: dffffc0000000000 R09: ffffed103de37f29
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000019
R13: ffff8881ef726070 R14: ffff8881ef726110 R15: 00000000000000c8
FS:  00007fe3403976c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a5c2a943b0 CR3: 00000001ef14f000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	df e8                	fucomip %st(0),%st
   2:	7d ad                	jge    0xffffffb1
   4:	fd                   	std
   5:	fe 4c 89 7c          	decb   0x7c(%rcx,%rcx,4)
   9:	24 18                	and    $0x18,%al
   b:	41 bf c8 00 00 00    	mov    $0xc8,%r15d
  11:	48 89 5c 24 08       	mov    %rbx,0x8(%rsp)
  16:	4c 03 3b             	add    (%rbx),%r15
  19:	4d 89 fc             	mov    %r15,%r12
  1c:	49 c1 ec 03          	shr    $0x3,%r12
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	41 0f b6 04 04       	movzbl (%r12,%rax,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 31 0e 00 00    	jne    0xe68
  37:	41 0f b6 1f          	movzbl (%r15),%ebx
  3b:	89 de                	mov    %ebx,%esi
  3d:	83 e6 01             	and    $0x1,%esi