WARNING in f2fs_delete_entry

Status: upstream: reported C repro on 2024/11/21 21:29
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+4ecfc6dcd5172a23fc28@syzkaller.appspotmail.com
First crash: 634d, last: 429d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2025/05/11 linux-6.1.y (ToT) 02b72ccb5f9d C [report] WARNING in f2fs_delete_entry
2024/11/22 upstream (ToT) 28eb75e178d3 C [report] WARNING in f2fs_delete_entry
2025/05/11 upstream (ToT) 3ce9925823c7 C Didn't crash
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in f2fs_delete_entry f2fs -1 syz, C 71 498d 634d 0/29 closed as dup on 2024/11/25 18:18
upstream WARNING in f2fs_delete_entry (2) f2fs -1 syz, C 4 311d 322d 29/29 fixed on 2026/01/07 12:29
linux-5.15 WARNING in f2fs_delete_entry missing-backport -1 syz, C error 11 434d 634d 0/3 auto-obsoleted due to no activity on 2025/09/18 06:39
▶ ▼ Fix bisection attempts (7)
Created Duration User Patch Repo Result
2026/05/24 23:10 25m fix candidate upstream error job log
2026/03/27 20:27 1m fix candidate upstream error job log
2026/02/25 02:56 8m fix candidate upstream error job log
2026/01/24 01:41 1m fix candidate upstream error job log
2025/08/03 16:31 15m fix candidate upstream error job log
2025/03/08 07:12 19m bisect fix linux-6.1.y error job log
2025/01/10 06:25 1h36m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Found nat_bits in checkpoint
F2FS-fs (loop0): Mounted with checkpoint version = 48b305e4
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4291 at fs/inode.c:332 drop_nlink+0xe4/0x138 fs/inode.c:332
Modules linked in:
CPU: 1 PID: 4291 Comm: syz-executor402 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : drop_nlink+0xe4/0x138 fs/inode.c:332
lr : drop_nlink+0xe4/0x138 fs/inode.c:332
sp : ffff800021167920
x29: ffff800021167920 x28: dfff800000000000 x27: dfff800000000000
x26: ffff0000d4ff7000 x25: 1fffe0001c353354 x24: ffff0000e1a99b18
x23: 1fffe0001c35335d x22: dfff800000000000 x21: 0000000000000000
x20: ffff0000e1a99ae8 x19: ffff0000e1a99aa0 x18: ffff800021167560
x17: ffff800018c59000 x16: ffff800008302888 x15: ffff800018739f80
x14: 0000000050785c76 x13: dfff800000000000 x12: 0000000000000003
x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff800008aace74
x8 : ffff0000deb41bc0 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff800018d95040 x4 : 0000000000000004 x3 : 0000000000000000
x2 : 0000000000000006 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 drop_nlink+0xe4/0x138 fs/inode.c:332
 f2fs_i_links_write fs/f2fs/f2fs.h:3044 [inline]
 f2fs_drop_nlink+0x110/0x34c fs/f2fs/dir.c:922
 f2fs_delete_entry+0xae4/0xefc fs/f2fs/dir.c:989
 f2fs_unlink+0x4b8/0xbdc fs/f2fs/namei.c:562
 vfs_unlink+0x2f0/0x508 fs/namei.c:4322
 do_unlinkat+0x4cc/0x70c fs/namei.c:4390
 __do_sys_unlinkat fs/namei.c:4433 [inline]
 __se_sys_unlinkat fs/namei.c:4426 [inline]
 __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4426
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 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: 251768
hardirqs last  enabled at (251767): [<ffff8000084041d8>] seqcount_lockdep_reader_access include/linux/seqlock.h:104 [inline]
hardirqs last  enabled at (251767): [<ffff8000084041d8>] ktime_get_coarse_real_ts64+0x114/0x244 kernel/time/timekeeping.c:2261
hardirqs last disabled at (251768): [<ffff80001232684c>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (251760): [<ffff8000081c40ac>] softirq_handle_end kernel/softirq.c:421 [inline]
softirqs last  enabled at (251760): [<ffff8000081c40ac>] handle_softirqs+0xb84/0xd58 kernel/softirq.c:606
softirqs last disabled at (251749): [<ffff800008020174>] __do_softirq+0x14/0x20 kernel/softirq.c:612
---[ end trace 0000000000000000 ]---

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/14 15:43 linux-6.1.y 420102835862 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2024/11/21 21:56 linux-6.1.y b67dc5c9ade9 4b25d554 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2025/06/15 14:32 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2025/05/05 08:17 linux-6.1.y b6736e03756f b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2025/05/05 08:17 linux-6.1.y b6736e03756f b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2025/04/14 15:19 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2025/02/05 14:02 linux-6.1.y 0cbb5f65e52f 5896748e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
2024/11/21 21:28 linux-6.1.y b67dc5c9ade9 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in f2fs_delete_entry
* Struck through repros no longer work on HEAD.