WARNING in nilfs_ioctl_prepare_clean_segments

Status: upstream: reported C repro on 2026/04/22 05:01
Reported-by: syzbot+509f05b180eba6a0348b@syzkaller.appspotmail.com
First crash: 98d, last: 59d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2026/07/13 upstream (ToT) 0f26556c5eee C Failed due to an error; will retry later
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in nilfs_ioctl_prepare_clean_segments origin:upstream -1 syz, C error 5 98d 116d 0/3 upstream: reported C repro on 2026/04/04 09:10
upstream WARNING in nilfs_ioctl_prepare_clean_segments nilfs -1 syz, C error 3 115d 135d 29/29 fixed on 2026/05/21 07:50

Sample crash report:
loop0: detected capacity change from 0 to 4096
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4517 at fs/nilfs2/ioctl.c:772 nilfs_ioctl_mark_blocks_dirty fs/nilfs2/ioctl.c:772 [inline]
WARNING: CPU: 0 PID: 4517 at fs/nilfs2/ioctl.c:772 nilfs_ioctl_prepare_clean_segments+0x724/0x730 fs/nilfs2/ioctl.c:814
Modules linked in:
CPU: 0 PID: 4517 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : nilfs_ioctl_mark_blocks_dirty fs/nilfs2/ioctl.c:772 [inline]
pc : nilfs_ioctl_prepare_clean_segments+0x724/0x730 fs/nilfs2/ioctl.c:814
lr : nilfs_ioctl_mark_blocks_dirty fs/nilfs2/ioctl.c:772 [inline]
lr : nilfs_ioctl_prepare_clean_segments+0x724/0x730 fs/nilfs2/ioctl.c:814
sp : ffff8000211d7600
x29: ffff8000211d76a0 x28: dfff800000000000 x27: 0000000000000000
x26: ffff8000208091b0 x25: ffff8000208091a8 x24: 00000000fffffffe
x23: 1ffff00004101235 x22: 1ffff00004101234 x21: ffff800020809190
x20: ffff0000d1eef2c8 x19: 000000000000000b x18: 0000000000000000
x17: ffff80001835b000 x16: ffff8000082d92bc x15: 0000000000000000
x14: 00000000fffffffe x13: 0000000000ff0100 x12: 0000000000ff0100
x11: ff00800009c9d1cc x10: 0000000000000000 x9 : ffff800009c9d1cc
x8 : ffff0000c341b780 x7 : ffff80000805983c x6 : ffff800008059a4c
x5 : ffff0000cd49e998 x4 : ffff8000211d6f20 x3 : ffff800008a90cc0
x2 : 0000000000000001 x1 : ffff800015880cb0 x0 : 00000000fffffffe
Call trace:
 nilfs_ioctl_mark_blocks_dirty fs/nilfs2/ioctl.c:772 [inline]
 nilfs_ioctl_prepare_clean_segments+0x724/0x730 fs/nilfs2/ioctl.c:814
 nilfs_clean_segments+0x148/0x870 fs/nilfs2/segment.c:2516
 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:940 [inline]
 nilfs_ioctl+0x22c0/0x2660 fs/nilfs2/ioctl.c:1304
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __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
irq event stamp: 14378
hardirqs last  enabled at (14377): [<ffff8000088e8344>] kasan_quarantine_put+0xc4/0x200 mm/kasan/quarantine.c:242
hardirqs last disabled at (14378): [<ffff800011a38ccc>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (14232): [<ffff800008030954>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (14230): [<ffff800008030920>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
NILFS (loop0): error -2 preparing GC: cannot mark copying blocks dirty

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/22 05:39 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 WARNING in nilfs_ioctl_prepare_clean_segments
2026/04/22 05:21 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 WARNING in nilfs_ioctl_prepare_clean_segments
2026/04/22 07:04 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in nilfs_ioctl_prepare_clean_segments
2026/05/31 19:49 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in nilfs_ioctl_prepare_clean_segments
2026/04/22 05:02 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in nilfs_ioctl_prepare_clean_segments
2026/04/22 05:01 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in nilfs_ioctl_prepare_clean_segments
* Struck through repros no longer work on HEAD.