Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 0 UID: 0 PID: 27149 Comm: syz.9.8514 Not tainted syzkaller #0 c79f1cffa6a5c09114654fbb1334511b20ee076b
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:d_really_is_positive include/linux/dcache.h:514 [inline]
RIP: 0010:open_or_create_special_dir+0x89/0x1e0 fs/incfs/vfs.c:460
Code: e8 bc 91 3e ff e9 07 01 00 00 e8 b2 91 3e ff 48 c7 c3 ea ff ff ff e9 f6 00 00 00 4c 89 6d d0 4c 8d 6b 30 4d 89 ef 49 c1 ef 03 <43> 80 3c 37 00 74 08 4c 89 ef e8 38 d7 94 ff 49 83 7d 00 00 74 26
RSP: 0018:ffffc9000313faf8 EFLAGS: 00010202
RAX: 0000000000000008 RBX: 0000000000000008 RCX: ffff888127e6a600
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88813d271328
RBP: ffffc9000313fb30 R08: ffff88813d27132b R09: 1ffff11027a4e265
R10: dffffc0000000000 R11: ffffed1027a4e266 R12: ffff88811a193180
R13: 0000000000000038 R14: dffffc0000000000 R15: 0000000000000007
FS:  00007fc3e91596c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564dd91ec660 CR3: 000000013ea3c000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 incfs_mount_fs+0x433/0x960 fs/incfs/vfs.c:1863
 legacy_get_tree+0x103/0x1b0 fs/fs_context.c:662
 vfs_get_tree+0x9e/0x290 fs/super.c:1817
 do_new_mount+0x251/0xb40 fs/namespace.c:3531
 path_mount+0x688/0x1050 fs/namespace.c:3858
 do_mount fs/namespace.c:3871 [inline]
 __do_sys_mount fs/namespace.c:4081 [inline]
 __se_sys_mount+0x2bd/0x480 fs/namespace.c:4058
 __x64_sys_mount+0xc3/0xf0 fs/namespace.c:4058
 x64_sys_call+0x2021/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc3e838eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc3e9159038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc3e85e6090 RCX: 00007fc3e838eec9
RDX: 0000200000000780 RSI: 0000200000000140 RDI: 0000200000000580
RBP: 00007fc3e8411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc3e85e6128 R14: 00007fc3e85e6090 R15: 00007ffdf40b4ad8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:d_really_is_positive include/linux/dcache.h:514 [inline]
RIP: 0010:open_or_create_special_dir+0x89/0x1e0 fs/incfs/vfs.c:460
Code: e8 bc 91 3e ff e9 07 01 00 00 e8 b2 91 3e ff 48 c7 c3 ea ff ff ff e9 f6 00 00 00 4c 89 6d d0 4c 8d 6b 30 4d 89 ef 49 c1 ef 03 <43> 80 3c 37 00 74 08 4c 89 ef e8 38 d7 94 ff 49 83 7d 00 00 74 26
RSP: 0018:ffffc9000313faf8 EFLAGS: 00010202
RAX: 0000000000000008 RBX: 0000000000000008 RCX: ffff888127e6a600
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88813d271328
RBP: ffffc9000313fb30 R08: ffff88813d27132b R09: 1ffff11027a4e265
R10: dffffc0000000000 R11: ffffed1027a4e266 R12: ffff88811a193180
R13: 0000000000000038 R14: dffffc0000000000 R15: 0000000000000007
FS:  00007fc3e91596c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561f62792300 CR3: 000000013ea3c000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000200ca8 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	e8 bc 91 3e ff       	call   0xff3e91c1
   5:	e9 07 01 00 00       	jmp    0x111
   a:	e8 b2 91 3e ff       	call   0xff3e91c1
   f:	48 c7 c3 ea ff ff ff 	mov    $0xffffffffffffffea,%rbx
  16:	e9 f6 00 00 00       	jmp    0x111
  1b:	4c 89 6d d0          	mov    %r13,-0x30(%rbp)
  1f:	4c 8d 6b 30          	lea    0x30(%rbx),%r13
  23:	4d 89 ef             	mov    %r13,%r15
  26:	49 c1 ef 03          	shr    $0x3,%r15
* 2a:	43 80 3c 37 00       	cmpb   $0x0,(%r15,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ef             	mov    %r13,%rdi
  34:	e8 38 d7 94 ff       	call   0xff94d771
  39:	49 83 7d 00 00       	cmpq   $0x0,0x0(%r13)
  3e:	74 26                	je     0x66