[syzbot] [ntfs3?] general protection fault in pick_link (2)

[syzbot <syzbot+1aa90f0eb1fc3e77d969@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    9afe652958c3 Merge tag 'x86_urgent_for_6.16-rc3' of git://..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10cf95d4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d11f52d3049c3790
dashboard link: https://syzkaller.appspot.com/bug?extid=1aa90f0eb1fc3e77d969
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11969e82580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14fd450c580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-9afe6529.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/46695f4e5fdb/vmlinux-9afe6529.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4357674be01a/bzImage-9afe6529.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/dd817d4f3932/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1aa90f0eb1fc3e77d969@syzkaller.appspotmail.com

ntfs3(loop0): ino=1b, "file0" ntfs_rename
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 5313 Comm: syz-executor352 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:pick_link+0x4f1/0xe80 fs/namei.c:1949
Code: 4c 89 f7 e8 81 fa ea ff 4d 8b 36 4d 85 f6 0f 84 9b 00 00 00 e8 50 7c 87 ff 49 bf 00 00 00 00 00 fc ff df 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 b9 06 00 00 41 0f b6 2e bf 2f 00 00 00
RSP: 0018:ffffc9000d2477e8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc9000d247908 RCX: ffff88801a34c880
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff823d3d98
R10: 000000003b9aca00 R11: ffffffff823cb0a0 R12: 1ffff92001a48f8b
R13: ffffc9000d247c20 R14: 0000000000000002 R15: dffffc0000000000
FS:  00005555725f0380(0000) GS:ffff88808d251000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4a1afaf000 CR3: 00000000438a8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 step_into+0xc5d/0xf30 fs/namei.c:2008
 open_last_lookups fs/namei.c:3843 [inline]
 path_openat+0x1bc6/0x3830 fs/namei.c:4052
 do_filp_open+0x1fa/0x410 fs/namei.c:4082
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_open fs/open.c:1460 [inline]
 __se_sys_open fs/open.c:1456 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1456
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5aa2adeed9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc2e7cf7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f5aa2b47ac0 RCX: 00007f5aa2adeed9
RDX: 0000000000000000 RSI: 0000000000048500 RDI: 0000200000000a80
RBP: 0000200000001240 R08: 00005555725f14c0 R09: 00005555725f14c0
R10: 00005555725f14c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc2e7cfa38 R14: 431bde82d7b634db R15: 00007f5aa2b2803b
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pick_link+0x4f1/0xe80 fs/namei.c:1949
Code: 4c 89 f7 e8 81 fa ea ff 4d 8b 36 4d 85 f6 0f 84 9b 00 00 00 e8 50 7c 87 ff 49 bf 00 00 00 00 00 fc ff df 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 b9 06 00 00 41 0f b6 2e bf 2f 00 00 00
RSP: 0018:ffffc9000d2477e8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc9000d247908 RCX: ffff88801a34c880
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff823d3d98
R10: 000000003b9aca00 R11: ffffffff823cb0a0 R12: 1ffff92001a48f8b
R13: ffffc9000d247c20 R14: 0000000000000002 R15: dffffc0000000000
FS:  00005555725f0380(0000) GS:ffff88808d251000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ff6c3df070 CR3: 00000000438a8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	4c 89 f7             	mov    %r14,%rdi
   3:	e8 81 fa ea ff       	call   0xffeafa89
   8:	4d 8b 36             	mov    (%r14),%r14
   b:	4d 85 f6             	test   %r14,%r14
   e:	0f 84 9b 00 00 00    	je     0xaf
  14:	e8 50 7c 87 ff       	call   0xff877c69
  19:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
  20:	fc ff df
  23:	4c 89 f0             	mov    %r14,%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:	0f 85 b9 06 00 00    	jne    0x6f0
  37:	41 0f b6 2e          	movzbl (%r14),%ebp
  3b:	bf 2f 00 00 00       	mov    $0x2f,%edi


---
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