CVE-2023-54124 f2fs: fix to drop all dirty pages during umount() if cp_error is set
A bug in the Linux kernel's f2fs filesystem causes a kernel panic during unmount when a checkpoint error is set, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-54124?
CVE-2023-54124 is a high-severity denial of service vulnerability in Linux, published on 24 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to drop all dirty pages during umount() if cp_error is set
xfstest generic/361 reports a bug as below:
f2fs_bug_on(sbi, sbi->fsync_node_num);
kernel BUG at fs/f2fs/super.c:1627! RIP: 0010:f2fs_put_super+0x3a8/0x3b0 Call Trace: generic_shutdown_super+0x8c/0x1b0 kill_block_super+0x2b/0x60 kill_f2fs_super+0x87/0x110 deactivate_locked_super+0x39/0x80 deactivate_super+0x46/0x50 cleanup_mnt+0x109/0x170 __cleanup_mnt+0x16/0x20 task_work_run+0x65/0xa0 exit_to_user_mode_prepare+0x175/0x190 syscall_exit_to_user_mode+0x25/0x50 do_syscall_64+0x4c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc
During umount(), if cp_error is set, f2fs_wait_on_all_pages() should not stop waiting all F2FS_WB_CP_DATA pages to be writebacked, otherwise, fsync_node_num can be non-zero after f2fs_wait_on_all_pages() causing this bug.
In this case, to avoid deadloop in f2fs_wait_on_all_pages(), it needs to drop all dirty pages rather than redirtying them.
Which versions are affected by CVE-2023-54124?
How do I fix CVE-2023-54124?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-54124 being exploited?
There is no known exploitation of CVE-2023-54124 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54124, DEBIAN-CVE-2023-54124, GHSA-f6pj-88hq-4vr4, UBUNTU-CVE-2023-54124.