f2fs: fix to do sanity check on summary info

published 2025-12-24 10 mo ago modified 2026-08-05 3 mo ago also EUVD-2022-55808

cvss: 7.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 10%
public exploits: 0; none known

In the Linux kernel, the following vulnerability has been resolved:

As Wenqing Liu reported in bugzilla:

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

BUG: KASAN: use-after-free in recover_data+0x63ae/0x6ae0 [f2fs] Read of size 4 at addr ffff8881464dcd80 by task mount/1013

CPU: 3 PID: 1013 Comm: mount Tainted: G W 6.0.0-rc4 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x45/0x5e print_report.cold+0xf3/0x68d kasan_report+0xa8/0x130 recover_data+0x63ae/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

The root cause is: in fuzzed image, SSA table is corrupted: ofs_in_node is larger than ADDRS_PER_PAGE(), result in out-of-range access on 4k-size page.

- recover_data - do_recover_data - check_index_in_prev_nodes - f2fs_data_blkaddr

This patch adds sanity check on summary info in recovery and GC flow in where the flows rely on them.

After patch: [ 29.310883] F2FS-fs (loop0): Inconsistent ofs_in_node:65286 in summary, ino:0, nid:6, max:1018

Patch / fix

fixed in 1 distros 2 links 6

Linux Linux 5.4.220, 5.10.150, 5.15.75, 5.19.17, 6.0.3, 6.1

debian ubuntu

linux Debian 14, Debian 13, Debian 12 6.0.3-1

debian advisories DEBIAN-CVE-2022-50753

linux Ubuntu 20.04 LTS 5.4.0-139.156
linux Ubuntu 22.04 LTS 5.15.0-60.66
linux-aws Ubuntu 20.04 LTS 5.4.0-1096.104
linux-aws Ubuntu 22.04 LTS 5.15.0-1030.34
linux-gcp Ubuntu 20.04 LTS 5.4.0-1100.109
linux-gcp Ubuntu 22.04 LTS 5.15.0-1029.36
linux-gke Ubuntu 22.04 LTS 5.15.0-1027.32
linux-ibm Ubuntu 20.04 LTS 5.4.0-1044.49

ubuntu advisories UBUNTU-CVE-2022-50753

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-50753 updated 2026-11-04 cvss 7.8

kernel: Linux kernel: F2FS use-after-free vulnerability leading to denial of service or arbitrary code execution

Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

Linux Linux

Classification

Technology feeds

Linux kernel rss critical rss

References

Sources

CVE List CVE-2022-50753
NVD CVE-2022-50753

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary