Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — f2fs: fix to do sanity check on sit_bitmap_size
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0016 5.5 —
AFFECTED
Product Versions Fixed
Linux 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 – —
Linux 3.8 – 5.10.239
TIMELINE
Apr 16 Reserved by Linux
Jul 4 Published (CNA: Linux)
Jul 30 RESCORED — CVE-2025-38218 (Linux). CVSS 7.8 → 5.5 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on sit_bitmap_size
w/ below testcase, resize will generate a corrupted image which
contains inconsistent metadata, so when mounting such image, it
will trigger kernel panic:
touch img
truncate -s $((512*1024*1024*1024)) img
mkfs.f2fs -f img $((256*1024*1024))
resize.f2fs -s -i img -t $((1024*1024*1024))
mount img /mnt/f2fs
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.h:863!
Oops: invalid opcode: 0000 [#1] SMP PTI
CPU: 11 UID: 0 PID: 3922 Comm: mount Not tainted 6.15.0-rc1+ #191 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:f2fs_ra_meta_pages+0x47c/0x490
Call Trace:
f2fs_build_segment_manager+0x11c3/0x2600
f2fs_fill_super+0xe97/0x2840
mount_bdev+0xf4/0x140
legacy_get_tree+0x2b/0x50
vfs_get_tree+0x29/0xd0
path_mount+0x487/0xaf0
__x64_sys_mount+0x116/0x150
do_syscall_64+0x82/0x190
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fdbfde1bcfe
The reaseon is:
sit_i->bitmap_size is 192, so size of sit bitmap is 192*8=1536, at maximum
there are 1536 sit blocks, however MAIN_SEGS is 261893, so that sit_blk_cnt
is 4762, build_sit_entries() -> current_sit_addr() tries to access
out-of-boundary in sit_bitmap at offset from [1536, 4762), once sit_bitmap
and sit_bitmap_mirror is not the same, it will trigger f2fs_bug_on().
Let's add sanity check in f2fs_sanity_check_ckpt() to avoid panic.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| April 16, 2025 | Reserved | Reserved by Linux |
| July 4, 2025 | Published | Published (CNA: Linux) |
| July 30, 2026 | RESCORED | RESCORED — CVE-2025-38218 (Linux). CVSS 7.8 → 5.5 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 | — |
| Linux | Linux | — | 3.8 | 5.10.239 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-38218 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.