RBP: 00007fcbe824a1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffec072aaff R14: 00007fcbe824a300 R15: 0000000000022000
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
Modules linked in:
CPU: 0 PID: 1549 Comm: syz-executor.1 Not tainted 4.14.290-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
task: ffff888095d48380 task.stack: ffff88809d478000
RIP: 0010:sysfs_do_create_link_sd+0x56/0x120 fs/sysfs/symlink.c:35
RSP: 0018:ffff88809d47fb48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000010 RCX: 00000000000067b9
RDX: 0000000000000008 RSI: 0000000000000001 RDI: 0000000000000040
RBP: ffffffff87cbc860 R08: ffffffff8b9d48c8 R09: 00000000000400cc
R10: ffff888095d48c30 R11: ffff888095d48380 R12: ffff8880ae87ca80
R13: ffffffff87cbc860 R14: 0000000000000001 R15: ffff8880a99743dc
FS:  00007fcbe824a700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007febc0ce86e0 CR3: 00000000a3139000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sysfs_do_create_link fs/sysfs/symlink.c:80 [inline]
 sysfs_create_link+0x5f/0xc0 fs/sysfs/symlink.c:92
 device_add_disk+0x9f8/0xdc0 block/genhd.c:691
 add_disk include/linux/genhd.h:396 [inline]
 loop_add+0x615/0x830 drivers/block/loop.c:1904
 loop_control_ioctl+0x11a/0x3f0 drivers/block/loop.c:2001
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fcbe98d5279
RSP: 002b:00007fcbe824a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcbe99e7f80 RCX: 00007fcbe98d5279
RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000003
RBP: 00007fcbe824a1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffec072aaff R14: 00007fcbe824a300 R15: 0000000000022000
Code: 84 a1 00 00 00 e8 8b 5e b1 ff 48 c7 c7 e0 d1 04 89 e8 0f 13 80 05 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a7 00 00 00 4c 8b 6b 30 4d 85 ed 74 4f e8 52 
RIP: sysfs_do_create_link_sd+0x56/0x120 fs/sysfs/symlink.c:35 RSP: ffff88809d47fb48
---[ end trace 623bc2da3b51b79b ]---
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	a1 00 00 00 e8 8b 5e 	movabs 0xffb15e8be8000000,%eax
   7:	b1 ff
   9:	48 c7 c7 e0 d1 04 89 	mov    $0xffffffff8904d1e0,%rdi
  10:	e8 0f 13 80 05       	callq  0x5801324
  15:	48 8d 7b 30          	lea    0x30(%rbx),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 a7 00 00 00    	jne    0xdb
  34:	4c 8b 6b 30          	mov    0x30(%rbx),%r13
  38:	4d 85 ed             	test   %r13,%r13
  3b:	74 4f                	je     0x8c
  3d:	e8                   	.byte 0xe8
  3e:	52                   	push   %rdx