[syzbot] [f2fs?] WARNING in f2fs_delete_entry (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2213e57a69f0 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=12a822e2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=714d45b6135c308e
dashboard link: https://syzkaller.appspot.com/bug?extid=c07d47c7bc68f47b9083
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1341fce2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=144ddd34580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bf4625d47a8f/disk-2213e57a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/270abffcbf3c/vmlinux-2213e57a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1f0f6eb3e385/Image-2213e57a.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/2f5997142143/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=135f62e2580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c07d47...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 6642 at fs/inode.c:417 drop_nlink+0xe4/0x138 fs/inode.c:417
Modules linked in:
CPU: 0 UID: 0 PID: 6642 Comm: syz-executor Not tainted syzkaller #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : drop_nlink+0xe4/0x138 fs/inode.c:417
lr : drop_nlink+0xe4/0x138 fs/inode.c:417
sp : ffff8000a54b79a0
x29: ffff8000a54b79a0 x28: dfff800000000000 x27: ffff0000efc5d000
x26: dfff800000000000 x25: 0000000200000000 x24: 0000000000000000
x23: 1fffe0001d284485 x22: dfff800000000000 x21: 0000000000000000
x20: ffff0000e9422428 x19: ffff0000e94223e0 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000805379bc x15: 0000000000000001
x14: 1fffe0001bd69171 x13: 0000000000000000 x12: 0000000000000000
x11: ffff60001bd69172 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000cdeb8000 x7 : ffff8000826e1b78 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff800080537ac4
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
drop_nlink+0xe4/0x138 fs/inode.c:417 (P)
f2fs_i_links_write fs/f2fs/f2fs.h:3233 [inline]
f2fs_drop_nlink+0x104/0x2e8 fs/f2fs/dir.c:849
f2fs_delete_entry+0x740/0x9a8 fs/f2fs/dir.c:911
f2fs_unlink+0x344/0xa3c fs/f2fs/namei.c:590
f2fs_rmdir+0x5c/0x7c fs/f2fs/namei.c:755
vfs_rmdir+0x328/0x464 fs/namei.c:4461
do_rmdir+0x214/0x4c4 fs/namei.c:4516
__do_sys_unlinkat fs/namei.c:4690 [inline]
__se_sys_unlinkat fs/namei.c:4684 [inline]
__arm64_sys_unlinkat+0xc8/0xf8 fs/namei.c:4684
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:763
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
irq event stamp: 143176
hardirqs last enabled at (143175): [<ffff8000806302f8>] seqcount_lockdep_reader_access+0x80/0x104 include/linux/seqlock.h:74
hardirqs last disabled at (143176): [<ffff80008b01a2c4>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:434
softirqs last enabled at (142090): [<ffff800080201608>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (142088): [<ffff8000802015d4>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---


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