CVE-2025-38580

Published Aug 19, 2025

Last updated 3 months ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix inode use after free in ext4_end_io_rsv_work() In ext4_io_end_defer_completion(), check if io_end->list_vec is empty to avoid adding an io_end that requires no conversion to the i_rsv_conversion_list, which in turn prevents starting an unnecessary worker. An ext4_emergency_state() check is also added to avoid attempting to abort the journal in an emergency state. Additionally, ext4_put_io_end_defer() is refactored to call ext4_io_end_defer_completion() directly instead of being open-coded. This also prevents starting an unnecessary worker when EXT4_IO_END_FAILED is set but data_err=abort is not enabled. This ensures that the check in ext4_put_io_end_defer() is consistent with the check in ext4_end_bio(). Otherwise, we might add an io_end to the i_rsv_conversion_list and then call ext4_finish_bio(), after which the inode could be freed before ext4_end_io_rsv_work() is called, triggering a use-after-free issue.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416

Social media

Hype score
Not currently trending

Configurations

Related CVEs

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References

Sources include official advisories and independent security research.