syzbot


WARNING in attr_data_get_block_locked (2)

Status: upstream: reported C repro on 2026/05/25 09:02
Subsystems: ntfs3
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+7be6ad5cb228286af3e3@syzkaller.appspotmail.com
First crash: 35d, last: 2d10h
Cause bisection: failed (error log, bisect log)
  
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
0734d650-082d-468b-894c-42f9d149d0ed assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in attr_data_get_block_locked (2) 2026/06/02 05:09 2026/06/02 05:09 2026/06/02 05:27 1095583bae1d2729a3b4be301cb6ddc85ced9e38

			
		
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [ntfs3?] WARNING in attr_data_get_block_locked (2) 0 (2) 2026/06/23 03:01
[syzbot] Monthly ntfs3 report (Jun 2026) 0 (1) 2026/06/02 20:32
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in attr_data_get_block_locked prio:high ntfs3 -1 C 12 50d 122d 29/29 fixed on 2026/05/21 07:50

Sample crash report:
WARNING: The mand mount option has been deprecated and
         and is ignored by this kernel. Remove the mand
         option from the mount to silence this warning.
=======================================================
ntfs3(loop0): Different NTFS sector size (1024) and media sector size (512).
ntfs3(loop0): Failed to load $Extend (-22).
ntfs3(loop0): Failed to initialize $Extend.
------------[ cut here ]------------
1
WARNING: fs/ntfs3/attrib.c:1237 at attr_data_get_block_locked+0x1936/0x2610 fs/ntfs3/attrib.c:1237, CPU#1: syz.0.17/5827
Modules linked in:
CPU: 1 UID: 0 PID: 5827 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:attr_data_get_block_locked+0x1936/0x2610 fs/ntfs3/attrib.c:1237
Code: b0 b1 a7 fe 89 9c 24 90 00 00 00 41 29 dc 0f 83 cc 00 00 00 e8 ab af a7 fe 41 bf ea ff ff ff e9 7c fa ff ff e8 9b af a7 fe 90 <0f> 0b 90 41 bf ea ff ff ff e9 68 fa ff ff 48 8b 84 24 d8 00 00 00
RSP: 0018:ffffc9000476f9a0 EFLAGS: 00010293
RAX: ffffffff831d47f5 RBX: 00000000ffffffff RCX: ffff888036b38000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000476fbe8 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f1385f R12: ffff88804c3010e8
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00005555611e4500(0000) GS:ffff888126242000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32863fff CR3: 000000003f434000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 attr_data_get_block+0x250/0x310 fs/ntfs3/attrib.c:982
 ntfs_fallocate+0x1048/0x12d0 fs/ntfs3/file.c:702
 vfs_fallocate+0x663/0x7f0 fs/open.c:338
 ksys_fallocate fs/open.c:362 [inline]
 __do_sys_fallocate fs/open.c:367 [inline]
 __se_sys_fallocate fs/open.c:365 [inline]
 __x64_sys_fallocate+0xbf/0x110 fs/open.c:365
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0d001ce59
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:00007ffc29a8c788 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007ff0d0295fa0 RCX: 00007ff0d001ce59
RDX: 0000000000080000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007ff0d00b2e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0d0295fac R14: 00007ff0d0295fa0 R15: 00007ff0d0295fa0
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/23 03:01 upstream 1dc18801be29 5a630be6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs WARNING in attr_data_get_block_locked
2026/06/23 02:00 upstream 1dc18801be29 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in attr_data_get_block_locked
2026/06/10 14:12 upstream acb7500801e9 f79bac11 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in attr_data_get_block_locked
2026/05/25 03:33 upstream 6a97c4d5262d c69befb3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in attr_data_get_block_locked
2026/05/21 09:00 upstream df685633c3db 41b8c833 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in attr_data_get_block_locked
* Struck through repros no longer work on HEAD.