CVE-2025-38220

Advisory lineage Upstream: 0 Downstream: 43
Analyzed
Published: 04 Jul 2025, 13:37
Last modified:11 May 2026, 21:23

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
v3.1 (nvd)
EPSS Score
0.08% LOW
0% probability +0.06%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

04 Jul 2025, 13:37
Published
Vulnerability first disclosed
11 May 2026, 21:23
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: only dirty folios when data journaling regular files fstest generic/388 occasionally reproduces a crash that looks as follows: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> ext4_block_zero_page_range+0x30c/0x380 [ext4] ext4_truncate+0x436/0x440 [ext4] ext4_process_orphan+0x5d/0x110 [ext4] ext4_orphan_cleanup+0x124/0x4f0 [ext4] ext4_fill_super+0x262d/0x3110 [ext4] get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x26/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4ed/0x6b0 do_syscall_64+0x82/0x170 ... This occurs when processing a symlink inode from the orphan list. The partial block zeroing code in the truncate path calls ext4_dirty_journalled_data() -> folio_mark_dirty(). The latter calls mapping->a_ops->dirty_folio(), but symlink inodes are not assigned an a_ops vector in ext4, hence the crash. To avoid this problem, update the ext4_dirty_journalled_data() helper to only mark the folio dirty on regular files (for which a_ops is assigned). This also matches the journaling logic in the ext4_symlink() creation path, where ext4_handle_dirty_metadata() is called directly.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.08%• Percentile: 23%

Techniques & Countermeasures

  • CWE-476•NULL Pointer Dereference

    The product dereferences a pointer that it expects to be valid but is NULL.

Affected Systems

  • linux•linux

    ≥ d84c9ebdac1e39bc7b036c0c829ee8c1956edabc, < cf6a4c4ac7b6e3214f25df594c9689a62f1bb456 | ≥ d84c9ebdac1e39bc7b036c0c829ee8c1956edabc, < be5f3061a6f904e3674257879e71881ceee5b673 | ≥ d84c9ebdac1e39bc7b036c0c829ee8c1956edabc, < d7af6eee8cd60f55aa8c5fe2b91f11ec0c9a0f27 | ≥ d84c9ebdac1e39bc7b036c0c829ee8c1956edabc, < e26268ff1dcae5662c1b96c35f18cfa6ab73d9de | 6.4

  • linux•linux_kernel

    ≥ 6.4, < 6.6.95 | ≥ 6.7, < 6.12.35 | ≥ 6.13, < 6.15.4

References (4)