CVE-2022-50273 f2fs: fix to do sanity check on destination blkaddr during recovery

Medium 5.5 Published Updated

A missing sanity check in the Linux kernel f2fs filesystem during recovery can cause a kernel panic if specific configuration options are enabled.

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-2022-50273?

CVE-2022-50273 is a medium-severity denial of service vulnerability in Linux kernel, published on 15 Sep 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 do sanity check on destination blkaddr during recovery

As Wenqing Liu reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=216456

loop5: detected capacity change from 0 to 131072 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): Bitmap was wrongly set, blk:5634 ------------[ cut here ]------------ WARNING: CPU: 3 PID: 1013 at fs/f2fs/segment.c:2198 RIP: 0010:update_sit_entry+0xa55/0x10b0 [f2fs] Call Trace: <TASK> f2fs_do_replace_block+0xa98/0x1890 [f2fs] f2fs_replace_block+0xeb/0x180 [f2fs] recover_data+0x1a69/0x6ae0 [f2fs] f2fs_recover_fsync_data+0x120d/0x1fc0 [f2fs] f2fs_fill_super+0x4665/0x61e0 [f2fs] mount_bdev+0x2cf/0x3b0 legacy_get_tree+0xed/0x1d0 vfs_get_tree+0x81/0x2b0 path_mount+0x47e/0x19d0 do_mount+0xce/0xf0 __x64_sys_mount+0x12c/0x1a0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd

If we enable CONFIG_F2FS_CHECK_FS config, it will trigger a kernel panic instead of warning.

The root cause is: in fuzzed image, SIT table is inconsistent with inode mapping table, result in triggering such warning during SIT table update.

This patch introduces a new flag DATA_GENERIC_ENHANCE_UPDATE, w/ this flag, data block recovery flow can check destination blkaddr's validation in SIT table, and skip f2fs_replace_block() to avoid inconsistent status.

Which versions are affected by CVE-2022-50273?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-50273?

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-2022-50273 being exploited?

There is no known exploitation of CVE-2022-50273 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2022-50273, GHSA-rgpr-5qqc-g899, UBUNTU-CVE-2022-50273.

Is CVE-2022-50273 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free