syzbot

general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 376 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__d_entry_type include/linux/dcache.h:394 [inline]
RIP: 0010:d_is_miss include/linux/dcache.h:399 [inline]
RIP: 0010:d_is_negative include/linux/dcache.h:445 [inline]
RIP: 0010:d_is_positive include/linux/dcache.h:455 [inline]
RIP: 0010:filename_create+0x2af/0x470 fs/namei.c:3890
Code: 89 de e8 d4 ea ae ff 85 db 0f 84 8d 00 00 00 e8 a7 e6 ae ff 48 8b 5c 24 20 4c 8b 74 24 18 e9 a4 00 00 00 48 89 c1 48 c1 e9 03 <42> 0f b6 0c 21 84 c9 0f 85 8e 01 00 00 44 8b 20 44 89 e6 81 e6 00
RSP: 0018:ffffc90000b17d60 EFLAGS: 00010203
RAX: 000000000000000d RBX: 1ffff92000162fd3 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff8881139fbcc0
RBP: ffffc90000b17e30 R08: ffffc90000b17c47 R09: 1ffff92000162f88
R10: dffffc0000000000 R11: fffff52000162f89 R12: dffffc0000000000
R13: ffffc90000b17e98 R14: 0000000000000600 R15: 000000000000000d
FS:  00007f91a02ff6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000afe0 CR3: 000000012c11e000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_mknodat+0xd7/0x7a0 fs/namei.c:4029
 __do_sys_mknod fs/namei.c:4075 [inline]
 __se_sys_mknod fs/namei.c:4073 [inline]
 __x64_sys_mknod+0x8e/0xa0 fs/namei.c:4073
 x64_sys_call+0x7d7/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:134
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f919f39acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f91a02ff028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f919f615fa0 RCX: 00007f919f39acb9
RDX: 0000000000000704 RSI: 00000000ffff8000 RDI: 00002000000002c0
RBP: 00007f919f408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f919f616038 R14: 00007f919f615fa0 R15: 00007ffccf08a308
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__d_entry_type include/linux/dcache.h:394 [inline]
RIP: 0010:d_is_miss include/linux/dcache.h:399 [inline]
RIP: 0010:d_is_negative include/linux/dcache.h:445 [inline]
RIP: 0010:d_is_positive include/linux/dcache.h:455 [inline]
RIP: 0010:filename_create+0x2af/0x470 fs/namei.c:3890
Code: 89 de e8 d4 ea ae ff 85 db 0f 84 8d 00 00 00 e8 a7 e6 ae ff 48 8b 5c 24 20 4c 8b 74 24 18 e9 a4 00 00 00 48 89 c1 48 c1 e9 03 <42> 0f b6 0c 21 84 c9 0f 85 8e 01 00 00 44 8b 20 44 89 e6 81 e6 00
RSP: 0018:ffffc90000b17d60 EFLAGS: 00010203
RAX: 000000000000000d RBX: 1ffff92000162fd3 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff8881139fbcc0
RBP: ffffc90000b17e30 R08: ffffc90000b17c47 R09: 1ffff92000162f88
R10: dffffc0000000000 R11: fffff52000162f89 R12: dffffc0000000000
R13: ffffc90000b17e98 R14: 0000000000000600 R15: 000000000000000d
FS:  00007f91a02ff6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000afe0 CR3: 000000012c11e000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 de                	mov    %ebx,%esi
   2:	e8 d4 ea ae ff       	call   0xffaeeadb
   7:	85 db                	test   %ebx,%ebx
   9:	0f 84 8d 00 00 00    	je     0x9c
   f:	e8 a7 e6 ae ff       	call   0xffaee6bb
  14:	48 8b 5c 24 20       	mov    0x20(%rsp),%rbx
  19:	4c 8b 74 24 18       	mov    0x18(%rsp),%r14
  1e:	e9 a4 00 00 00       	jmp    0xc7
  23:	48 89 c1             	mov    %rax,%rcx
  26:	48 c1 e9 03          	shr    $0x3,%rcx
* 2a:	42 0f b6 0c 21       	movzbl (%rcx,%r12,1),%ecx <-- trapping instruction
  2f:	84 c9                	test   %cl,%cl
  31:	0f 85 8e 01 00 00    	jne    0x1c5
  37:	44 8b 20             	mov    (%rax),%r12d
  3a:	44 89 e6             	mov    %r12d,%esi
  3d:	81                   	.byte 0x81
  3e:	e6 00                	out    %al,$0x0