iommufd_mock iommufd_mock0: Removing from iommu group 0
general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 1 PID: 8581 Comm: syz-executor.1 Not tainted 6.5.0-rc5-next-20230809-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:sysfs_remove_link_from_group+0x2b/0x80 fs/sysfs/group.c:413
Code: 0f 1e fa 41 54 49 89 d4 55 48 89 f5 53 48 89 fb e8 7a e5 71 ff 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 75 39 48 8b 7b 30 31 d2 48 89 ee e8 81 f2 fe ff 48 85
RSP: 0018:ffffc900154e7c50 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8215e206 RDI: 0000000000000030
RBP: ffffffff8adb50a0 R08: 0000000000000001 R09: ffffed10028cef1b
R10: ffff8880146778df R11: ffffffff8a40008b R12: ffff88807dd211e0
R13: ffffffff8d520140 R14: ffff888020878450 R15: ffff888020878448
FS:  000055555632c480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc820c56be CR3: 00000000282c1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 iommu_deinit_device+0x111/0x5a0 drivers/iommu/iommu.c:411
 __iommu_group_remove_device+0x2e3/0x430 drivers/iommu/iommu.c:582
 iommu_group_remove_device+0x91/0xb0 drivers/iommu/iommu.c:1193
 mock_dev_destroy drivers/iommu/iommufd/selftest.c:396 [inline]
 iommufd_selftest_destroy+0xe2/0x180 drivers/iommu/iommufd/selftest.c:988
 iommufd_fops_release+0x1b9/0x320 drivers/iommu/iommufd/main.c:268
 __fput+0x3f7/0xac0 fs/file_table.c:384
 task_work_run+0x14d/0x240 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f40b627b9da
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffc4010dda0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00007f40b627b9da
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000032 R08: 0000001b31220000 R09: 00000000000000c6
R10: 0000000081738ed4 R11: 0000000000000293 R12: 00007f40b5e005a8
R13: ffffffffffffffff R14: 00007f40b5e00000 R15: 0000000000063f29
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:sysfs_remove_link_from_group+0x2b/0x80 fs/sysfs/group.c:413
Code: 0f 1e fa 41 54 49 89 d4 55 48 89 f5 53 48 89 fb e8 7a e5 71 ff 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 75 39 48 8b 7b 30 31 d2 48 89 ee e8 81 f2 fe ff 48 85
RSP: 0018:ffffc900154e7c50 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8215e206 RDI: 0000000000000030
RBP: ffffffff8adb50a0 R08: 0000000000000001 R09: ffffed10028cef1b
R10: ffff8880146778df R11: ffffffff8a40008b R12: ffff88807dd211e0
R13: ffffffff8d520140 R14: ffff888020878450 R15: ffff888020878448
FS:  000055555632c480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f26b0557000 CR3: 00000000282c1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	0f 1e fa             	nop    %edx
   3:	41 54                	push   %r12
   5:	49 89 d4             	mov    %rdx,%r12
   8:	55                   	push   %rbp
   9:	48 89 f5             	mov    %rsi,%rbp
   c:	53                   	push   %rbx
   d:	48 89 fb             	mov    %rdi,%rbx
  10:	e8 7a e5 71 ff       	call   0xff71e58f
  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:	75 39                	jne    0x69
  30:	48 8b 7b 30          	mov    0x30(%rbx),%rdi
  34:	31 d2                	xor    %edx,%edx
  36:	48 89 ee             	mov    %rbp,%rsi
  39:	e8 81 f2 fe ff       	call   0xfffef2bf
  3e:	48                   	rex.W
  3f:	85                   	.byte 0x85