general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
CPU: 1 PID: 8983 Comm: syz-executor.3 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:workqueue_sysfs_unregister kernel/workqueue.c:5689 [inline]
RIP: 0010:destroy_workqueue+0x25/0x5f0 kernel/workqueue.c:4349
Code: 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 41 55 41 54 55 48 89 fd 48 81 c7 08 01 00 00 48 89 fa 53 48 c1 ea 03 <80> 3c 02 00 0f 85 e8 04 00 00 48 8b 85 08 01 00 00 48 85 c0 74 14
RSP: 0018:ffffc90002af7d38 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff888218aab8f0 RCX: 0000000000000000
RDX: 0000000000000021 RSI: 0000000000000008 RDI: 0000000000000108
RBP: 0000000000000000 R08: fffffbfff165d57e R09: fffffbfff165d57e
R10: fffffbfff165d57d R11: ffffffff8b2eabef R12: ffffffff87cc1060
R13: 0000000000000000 R14: ffff888091b487c0 R15: 00000000080e001f
FS:  0000000002bff940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000625208 CR3: 000000009b966000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 loop_unprepare_queue drivers/block/loop.c:895 [inline]
 __loop_clr_fd+0x15a/0x1070 drivers/block/loop.c:1211
 __blkdev_driver_ioctl block/ioctl.c:321 [inline]
 blkdev_ioctl+0x4ab/0x580 block/ioctl.c:717
 block_ioctl+0xcc/0x120 fs/block_dev.c:1983
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0xb8/0x110 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770
 do_syscall_64+0xc6/0x5e0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c317
Code: 48 83 c4 08 48 89 d8 5b 5d c3 66 0f 1f 84 00 00 00 00 00 48 89 e8 48 f7 d8 48 39 c3 0f 92 c0 eb 92 66 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 0d b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff85fe1d58 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045c317
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003
RBP: 0000000000000002 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff85fe1d90 R14: 0000000000014eab R15: 00007fff85fe1da0
Modules linked in:
---[ end trace 38a2823d53a6182b ]---
RIP: 0010:workqueue_sysfs_unregister kernel/workqueue.c:5689 [inline]
RIP: 0010:destroy_workqueue+0x25/0x5f0 kernel/workqueue.c:4349
Code: 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 41 55 41 54 55 48 89 fd 48 81 c7 08 01 00 00 48 89 fa 53 48 c1 ea 03 <80> 3c 02 00 0f 85 e8 04 00 00 48 8b 85 08 01 00 00 48 85 c0 74 14
RSP: 0018:ffffc90002af7d38 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff888218aab8f0 RCX: 0000000000000000
RDX: 0000000000000021 RSI: 0000000000000008 RDI: 0000000000000108
RBP: 0000000000000000 R08: fffffbfff165d57e R09: fffffbfff165d57e
R10: fffffbfff165d57d R11: ffffffff8b2eabef R12: ffffffff87cc1060
R13: 0000000000000000 R14: ffff888091b487c0 R15: 00000000080e001f
FS:  0000000002bff940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000076c000 CR3: 000000009b966000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400