RBP: 00007efe64b9e47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007efe64c72050 R15: 00007ffe4bd33828
---[ end trace e22cd4d776b97f19 ]---
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 12047 Comm: syz-executor.4 Tainted: G        W         5.10.194-syzkaller-00508-ga27512601c2d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:strlen+0x2c/0x70 lib/string.c:568
Code: 89 e5 41 57 41 56 41 54 53 49 89 fe 48 c7 c0 ff ff ff ff 49 bf 00 00 00 00 00 fc ff df 48 89 fb 49 89 c4 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 12 48 ff c3 49 8d 44 24 01 43 80 7c 26 01
RSP: 0018:ffffc90006ff7ba8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90001f2a001
RDX: 00000000001fffe0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90006ff7bc8 R08: ffffffff81d2b6cb R09: 000000000000ffff
R10: 0000000000200000 R11: dffffc0000000001 R12: ffffffffffffffff
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007efe638b46c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020404030 CR3: 0000000116ac1000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kernfs_name_hash fs/kernfs/dir.c:310 [inline]
 kernfs_find_ns+0x95/0x4a0 fs/kernfs/dir.c:851
 kernfs_remove_by_name_ns+0x3a/0x110 fs/kernfs/dir.c:1523
 kernfs_remove_by_name include/linux/kernfs.h:608 [inline]
 sysfs_remove_link+0x50/0x60 fs/sysfs/symlink.c:152
 del_gendisk+0x87b/0xa90 block/genhd.c:951
 loop_remove+0x46/0xb0 drivers/block/loop.c:2210
 loop_control_ioctl+0x564/0x620 drivers/block/loop.c:2309
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x114/0x190 fs/ioctl.c:739
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:739
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xc6
RIP: 0033:0x7efe64b52ae9
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:00007efe638b40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007efe64c72050 RCX: 00007efe64b52ae9
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000005
RBP: 00007efe64b9e47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007efe64c72050 R15: 00007ffe4bd33828
Modules linked in:
---[ end trace e22cd4d776b97f1a ]---
RIP: 0010:strlen+0x2c/0x70 lib/string.c:568
Code: 89 e5 41 57 41 56 41 54 53 49 89 fe 48 c7 c0 ff ff ff ff 49 bf 00 00 00 00 00 fc ff df 48 89 fb 49 89 c4 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 12 48 ff c3 49 8d 44 24 01 43 80 7c 26 01
RSP: 0018:ffffc90006ff7ba8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90001f2a001
RDX: 00000000001fffe0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90006ff7bc8 R08: ffffffff81d2b6cb R09: 000000000000ffff
R10: 0000000000200000 R11: dffffc0000000001 R12: ffffffffffffffff
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007efe638b46c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020404030 CR3: 0000000116ac1000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 e5                	mov    %esp,%ebp
   2:	41 57                	push   %r15
   4:	41 56                	push   %r14
   6:	41 54                	push   %r12
   8:	53                   	push   %rbx
   9:	49 89 fe             	mov    %rdi,%r14
   c:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
  13:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
  1a:	fc ff df
  1d:	48 89 fb             	mov    %rdi,%rbx
  20:	49 89 c4             	mov    %rax,%r12
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 38       	movzbl (%rax,%r15,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	75 12                	jne    0x45
  33:	48 ff c3             	inc    %rbx
  36:	49 8d 44 24 01       	lea    0x1(%r12),%rax
  3b:	43                   	rex.XB
  3c:	80                   	.byte 0x80
  3d:	7c 26                	jl     0x65
  3f:	01                   	.byte 0x1