syzbot


WARNING in nilfs_btree_assign (3)

Status: upstream: reported C repro on 2025/01/14 07:40
Subsystems: nilfs
[Documentation on labels]
Reported-by: syzbot+158be45e4d99232e1900@syzkaller.appspotmail.com
First crash: 350d, last: 7d02h
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: WARNING in account_page_dirtied (log)
Repro: C syz .config
  
Discussions (8)
Title Replies (including bot) Last reply
[syzbot] Monthly nilfs report (Dec 2025) 0 (1) 2025/12/12 13:38
[syzbot] Monthly nilfs report (Oct 2025) 0 (1) 2025/10/04 09:17
[syzbot] Monthly nilfs report (Sep 2025) 0 (1) 2025/09/02 13:36
[syzbot] Monthly nilfs report (Jun 2025) 0 (1) 2025/06/30 10:11
[syzbot] Monthly nilfs report (Apr 2025) 0 (1) 2025/04/03 07:06
[syzbot] Monthly nilfs report (Mar 2025) 0 (1) 2025/03/03 10:39
[syzbot] Monthly nilfs report (Jan 2025) 0 (1) 2025/01/31 10:07
[syzbot] [nilfs?] WARNING in nilfs_btree_assign (3) 2 (5) 2025/01/14 12:28
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in nilfs_btree_assign origin:upstream missing-backport -1 C unreliable 18 840d 1010d 0/3 upstream: reported C repro on 2023/03/22 07:45
upstream WARNING in nilfs_btree_assign (2) nilfs -1 1 759d 755d 0/29 auto-obsoleted due to no activity on 2024/03/08 05:10
linux-4.14 WARNING in nilfs_btree_assign nilfs2 -1 C 7 1043d 1155d 0/1 upstream: reported C repro on 2022/10/28 16:42
upstream WARNING in nilfs_btree_assign nilfs -1 C error 799 885d 1188d 23/29 fixed on 2023/09/28 17:51
linux-5.15 WARNING in nilfs_btree_assign -1 C done 26 921d 996d 3/3 fixed on 2023/08/10 11:37
Last patch testing requests (12)
Created Duration User Patch Repo Result
2025/12/14 11:26 16m retest repro upstream report log
2025/12/14 11:26 18m retest repro upstream report log
2025/11/30 10:13 20m retest repro upstream report log
2025/11/30 10:13 16m retest repro upstream report log
2025/10/11 22:33 38m retest repro upstream report log
2025/09/22 11:35 18m retest repro upstream report log
2025/09/22 11:35 18m retest repro upstream report log
2025/09/08 01:02 19m retest repro upstream report log
2025/09/08 01:02 20m retest repro upstream report log
2025/07/01 05:30 15m retest repro upstream report log
2025/01/14 11:28 13m konishi.ryusuke@gmail.com patch upstream report log
2025/01/14 10:34 16m konishi.ryusuke@gmail.com patch upstream report log
Fix bisection attempts (6)
Created Duration User Patch Repo Result
2025/11/16 08:20 1h42m bisect fix upstream OK (0) job log log
2025/08/02 02:05 1h48m bisect fix upstream OK (0) job log log
2025/06/16 20:59 2h41m bisect fix upstream OK (0) job log log
2025/05/15 00:49 5h08m bisect fix upstream OK (0) job log log
2025/03/29 19:45 2h06m bisect fix upstream OK (0) job log log
2025/02/24 14:25 1h38m bisect fix upstream OK (0) job log log

Sample crash report:
NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds
------------[ cut here ]------------
WARNING: fs/nilfs2/btree.c:2302 at nilfs_btree_assign+0x983/0xbe0 fs/nilfs2/btree.c:2302, CPU#1: segctord/6073
Modules linked in:
CPU: 1 UID: 0 PID: 6073 Comm: segctord Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:nilfs_btree_assign+0x983/0xbe0 fs/nilfs2/btree.c:2302
Code: 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 9f 85 34 fe 49 bf 00 00 00 00 00 fc ff df eb 9a e8 8e 85 34 fe 90 <0f> 0b 90 41 be fe ff ff ff 49 bf 00 00 00 00 00 fc ff df e9 7c ff
RSP: 0018:ffffc90003f474a0 EFLAGS: 00010293
RAX: ffffffff838bde52 RBX: 0000000000000000 RCX: ffff888036553c80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003f475d0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1008689d04 R12: ffff88804366c3e8
R13: ffffc90003f47960 R14: 00000000fffffffe R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff888126e01000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faea2772000 CR3: 00000000389c0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 nilfs_bmap_assign+0x92/0x170 fs/nilfs2/bmap.c:374
 nilfs_segctor_update_payload_blocknr fs/nilfs2/segment.c:1640 [inline]
 nilfs_segctor_assign fs/nilfs2/segment.c:1674 [inline]
 nilfs_segctor_do_construct+0x33b7/0x6a40 fs/nilfs2/segment.c:2133
 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2462
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2570 [inline]
 nilfs_segctor_thread+0x6f7/0xe00 fs/nilfs2/segment.c:2684
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/20 03:36 upstream dd9b004b7ff3 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/01/10 14:57 upstream 643e2e259c2b 67d7ec0a .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/01/10 13:40 upstream 643e2e259c2b 67d7ec0a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/01/10 09:13 upstream 643e2e259c2b 67d7ec0a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/08/25 00:56 upstream 69fd6b99b8f8 bf27483f .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root WARNING in nilfs_btree_assign
2025/08/24 11:52 upstream 8d245acc1e88 bf27483f .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root WARNING in nilfs_btree_assign
2025/12/20 02:34 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/12/20 02:34 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in nilfs_btree_assign
2025/01/10 07:36 upstream 643e2e259c2b 67d7ec0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in nilfs_btree_assign
* Struck through repros no longer work on HEAD.