syzbot


kernel BUG in ntfs_truncate

Status: upstream: reported C repro on 2025/06/07 18:12
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+1160900da64cca2d5003@syzkaller.appspotmail.com
First crash: 283d, last: 10d
Fix bisection: failed (error log, bisect log)
  
Bug presence (2)
Date Name Commit Repro Result
2025/06/09 linux-6.1.y (ToT) 58485ff1a74f C [report] kernel BUG in ntfs_truncate
2025/06/09 upstream (ToT) 19272b37aa4f C Didn't crash
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 kernel BUG in ntfs_truncate origin:lts-only -1 C error 3 16d 584d 0/3 upstream: reported C repro on 2024/08/10 18:43
upstream kernel BUG in ntfs_truncate ntfs3 -1 C error done 4 812d 1170d 25/29 fixed on 2024/01/31 13:17
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/09/17 22:39 2h01m fix candidate upstream OK (0) job log
2025/07/12 19:38 14m bisect fix linux-6.1.y error job log

Sample crash report:
loop0: detected capacity change from 0 to 4096
ntfs: volume version 3.1.
------------[ cut here ]------------
kernel BUG at fs/ntfs/inode.c:2536!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4454 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ntfs_truncate+0x1f68/0x2120 fs/ntfs/inode.c:2536
lr : ntfs_truncate+0x1f68/0x2120 fs/ntfs/inode.c:2536
sp : ffff800020b77490
x29: ffff800020b77590 x28: ffff0000e59273d0 x27: ffff0000d8216e00
x26: ffff0000e5927410 x25: ffff0000e1436838 x24: ffff0000e59276f0
x23: 0000000000000000 x22: dfff800000000000 x21: 000000000000000a
x20: ffff0000e5927380 x19: ffff0000e5927380 x18: ffff800011b8bf60
x17: ffff800018349000 x16: ffff8000082d91a4 x15: 0000000000000000
x14: 00000000ffffffde x13: 0000000000ff0100 x12: 0000000000ff0100
x11: ff00800009565ee8 x10: 0000000000000000 x9 : ffff800009565ee8
x8 : ffff0000d6dd8000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000020 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000000 x1 : 00000000ffffffe4 x0 : 0000000000000000
Call trace:
 ntfs_truncate+0x1f68/0x2120 fs/ntfs/inode.c:2536
 ntfs_truncate_vfs fs/ntfs/inode.c:2862 [inline]
 ntfs_setattr+0x260/0x320 fs/ntfs/inode.c:2914
 notify_change+0xb0c/0xdcc fs/attr.c:499
 do_truncate+0x188/0x20c fs/open.c:65
 handle_truncate fs/namei.c:3293 [inline]
 do_open fs/namei.c:3638 [inline]
 path_openat+0x2110/0x26bc fs/namei.c:3791
 do_filp_open+0x194/0x384 fs/namei.c:3818
 do_sys_openat2+0x134/0x3f4 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __arm64_sys_openat+0x118/0x14c fs/open.c:1347
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 17fffb1a 97bd14f7 d4210000 97bd14f5 (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/07 12:15 linux-6.1.y f2ddafa93a25 5cb44a80 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ntfs_truncate
2025/06/07 20:12 linux-6.1.y 58485ff1a74f 4826c28e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ntfs_truncate
2025/06/07 19:36 linux-6.1.y 58485ff1a74f 4826c28e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ntfs_truncate
2025/06/07 18:56 linux-6.1.y 58485ff1a74f 4826c28e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ntfs_truncate
2025/06/07 18:12 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ntfs_truncate
* Struck through repros no longer work on HEAD.