[syzbot] [ntfs3?] WARNING in attr_data_get_block_locked

syzbot
2026-02-23T11:56:28Z

Hello,

syzbot found the following issue on:

HEAD commit: 956b9cbd7f15 Merge tag 'kbuild-fixes-7.0-1' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=148bb15a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=65722f41f7edc17e
dashboard link: https://syzkaller.appspot.com/bug?extid=c1e9aedbd913fadad617
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14f61ffa580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15833b3a580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-956b9cbd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0b3757a15ed/vmlinux-956b9cbd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c564e8613b4e/bzImage-956b9cbd.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/30f6900c6fc3/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c1e9aedbd913fadad617@syzkaller.appspotmail.com

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1
WARNING: fs/ntfs3/attrib.c:1222 at attr_data_get_block_locked+0x174a/0x22a0 fs/ntfs3/attrib.c:1222, CPU#0: syz.0.17/5462
Modules linked in:
CPU: 0 UID: 0 PID: 5462 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:attr_data_get_block_locked+0x174a/0x22a0 fs/ntfs3/attrib.c:1222
Code: 89 ee 49 89 d6 e8 d6 19 a6 fe 4d 89 f2 44 89 ac 24 bc 00 00 00 45 29 ea 73 1e e8 01 18 a6 fe e9 47 f9 ff ff e8 f7 17 a6 fe 90 <0f> 0b 90 41 bf ea ff ff ff e9 d6 fa ff ff 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc900049079c0 EFLAGS: 00010293
RAX: ffffffff831f83a9 RBX: 00000000ffffffff RCX: ffff888000ea0000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 00000000ffffffff
RBP: ffffc90004907be8 R08: 0000000000000000 R09: 1ffff11002487041
R10: dffffc0000000000 R11: ffffed1002487042 R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000002000 R15: 0000000000000007
FS: 000055558ba85500(0000) GS:ffff88808ca5b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd19d7909c0 CR3: 0000000012819000 CR4: 0000000000352ef0
Call Trace:
<TASK>
attr_data_get_block+0x250/0x310 fs/ntfs3/attrib.c:982
ntfs_fallocate+0xfac/0x1220 fs/ntfs3/file.c:677
vfs_fallocate+0x669/0x7e0 fs/open.c:340
ksys_fallocate fs/open.c:364 [inline]
__do_sys_fallocate fs/open.c:369 [inline]
__se_sys_fallocate fs/open.c:367 [inline]
__x64_sys_fallocate+0xc0/0x110 fs/open.c:367
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e3d39c629
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:00007fffbfb65448 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f1e3d615fa0 RCX: 00007f1e3d39c629
RDX: 0000000000007351 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007f1e3d432b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1e3d615fac R14: 00007f1e3d615fa0 R15: 00007f1e3d615fa0
</TASK>

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