WARNING: lock held when returning to user space in f2fs_write_single_data

WARNING: lock held when returning to user space in f2fs_write_single_data_page

Status: fixed on 2024/07/27 10:29
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+d0ab8746c920a592aeab@syzkaller.appspotmail.com
Fix commit: f2ba11ba9325 f2fs: avoid dead loop in f2fs_issue_checkpoint()
First crash: 541d, last: 337d

Fix commit to backport (bisect log) :
tree: upstream
commit 5079e1c0c879311668b77075de3e701869804adf
Author: Chao Yu <chao@kernel.org>
Date: Fri Jun 2 08:36:05 2023 +0000

f2fs: avoid dead loop in f2fs_issue_checkpoint()

Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: no output from test machine (log)
Repro: C syz .config

▶ ▼ Bug presence (3)

Date	Name	Commit	Repro	Result
2023/08/29	linux-6.1.y (ToT)	024f76bca9d0	C	[report] no output from test machine
2023/05/30	upstream (ToT)	afead42fdfca	C	[report] WARNING: lock held when returning to user space in f2fs_write_single_data_page
2023/08/29	upstream (ToT)	d68b4b6f307d	C	Didn't crash

▶ ▼ Similar bugs (1)

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	WARNING: lock held when returning to user space in f2fs_write_single_data_page f2fs	C	error	done	4	509d	569d	0/28	auto-obsoleted due to no activity on 2023/10/09 15:00

▶ ▼ Fix bisection attempts (6)


Created	Duration	User	Repo	Result
2023/12/26 20:51	6h13m	fix candidate	upstream	OK (1) job log
2023/12/20 08:07	2h02m	bisect fix	linux-6.1.y	OK (0) job log log
2023/11/20 04:57	1h46m	bisect fix	linux-6.1.y	OK (0) job log log
2023/10/18 08:18	1h40m	bisect fix	linux-6.1.y	OK (0) job log log
2023/09/13 17:11	2h04m	bisect fix	linux-6.1.y	OK (0) job log log
2023/06/30 01:48	1h23m	bisect fix	linux-6.1.y	OK (0) job log log

Sample crash report:

F2FS-fs (loop0): Mounted with checkpoint version = 753bd00b
syz-executor137: attempt to access beyond end of device
loop0: rw=2049, sector=77824, nr_sectors = 4096 limit=63271
================================================
WARNING: lock held when returning to user space!
6.1.30-syzkaller #0 Not tainted
------------------------------------------------
syz-executor137/3566 is leaving the kernel with locks still held!
1 lock held by syz-executor137/3566:
 #0: ffff888028ef0448 (&sbi->node_write){++++}-{3:3}, at: f2fs_down_read fs/f2fs/f2fs.h:2154 [inline]
 #0: ffff888028ef0448 (&sbi->node_write){++++}-{3:3}, at: f2fs_write_single_data_page+0xb72/0x2020 fs/f2fs/data.c:2826

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2023/05/30 10:33	linux-6.1.y	a343b0dd87b4	cf184559	.config	console log	report	syz	C		[disk image] [vmlinux] [kernel image] [mounted in repro]	ci2-linux-6-1-kasan	WARNING: lock held when returning to user space in f2fs_write_single_data_page

* ~~Struck through~~ repros no longer work on HEAD.