linux-kernel - [syzbot] [f2fs?] kernel BUG in f2fs_put

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Message-ID: <67f9db05.050a0220.379d84.0004.GAE@google.com>
Date: Fri, 11 Apr 2025 20:16:21 -0700
From: syzbot <syzbot+1badb065d3258a08f5e2@...kaller.appspotmail.com>
To: chao@...nel.org, jaegeuk@...nel.org, 
	linux-f2fs-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [f2fs?] kernel BUG in f2fs_put_super (3)

Hello,

syzbot found the following issue on:

HEAD commit:    0af2f6be1b42 Linux 6.15-rc1
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=11464c04580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cd7cb758c9c7b24c
dashboard link: https://syzkaller.appspot.com/bug?extid=1badb065d3258a08f5e2
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d136202c0eb5/disk-0af2f6be.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3adf5299bf86/vmlinux-0af2f6be.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3f351885eecb/Image-0af2f6be.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1badb065d3258a08f5e2@...kaller.appspotmail.com

F2FS-fs (loop2): detect filesystem reference count leak during umount, type: 9, count: 4
------------[ cut here ]------------
kernel BUG at fs/f2fs/super.c:1674!
Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6486 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-g0af2f6be1b42 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : f2fs_put_super+0xea4/0xef0 fs/f2fs/super.c:1672
lr : f2fs_put_super+0xea4/0xef0 fs/f2fs/super.c:1672
sp : ffff8000a0c17960
x29: ffff8000a0c17a50 x28: ffff8000a0c17980 x27: dfff800000000000
x26: ffff700014182f30 x25: ffff0000cac24000 x24: 0000000000002ff5
x23: ffff0000cc3a6087 x22: ffff0000cc3a6087 x21: 0000000000000004
x20: 0000000000000009 x19: ffff0000c6fc0000 x18: 0000000000000008
x17: 00000000fffffffa x16: ffff8000833376cc x15: 0000000000000001
x14: 1ffff00014182e60 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000ff0100 x9 : 6e36701c3beb6900
x8 : 6e36701c3beb6900 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a0c16fd8 x4 : ffff800090035280 x3 : ffff8000832c7c3c
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000058
Call trace:
 f2fs_put_super+0xea4/0xef0 fs/f2fs/super.c:1672 (P)
 generic_shutdown_super+0x12c/0x2bc fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1710
 kill_f2fs_super+0x2b4/0x590 fs/f2fs/super.c:5032
 deactivate_locked_super+0xc4/0x12c fs/super.c:473
 deactivate_super+0xe0/0x100 fs/super.c:506
 cleanup_mnt+0x34c/0x3dc fs/namespace.c:1435
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1442
 task_work_run+0x230/0x2e0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 do_notify_resume+0x178/0x1f4 arch/arm64/kernel/entry-common.c:151
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
 el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:745
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: aa1303e0 2a1f03e1 2a1403e3 97ff825f (d4210000) 
---[ end trace 0000000000000000 ]---


---
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