CVE-2022-49408: ext4: fix memory leak in parse_apply_sb_mount_options()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-02-26 · updated 2026-06-17
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in parse_apply_sb_mount_options() If processing the on-disk mount options fails after any memory was allocated in the ext4_fs_context, e.g. s_qf_names, then this memory is leaked. Fix this by calling ext4_fc_free() instead of kfree() directly. Reproducer: mkfs.ext4 -F /dev/vdc tune2fs /dev/vdc -E mount_opts=usrjquota=file echo clear > /sys/kernel/debug/kmemleak mount /dev/vdc /vdc echo scan > /sys/kernel/debug/kmemleak sleep 5 echo scan > /sys/kernel/debug/kmemleak cat /sys/kernel/debug/kmemleak

Affected products

Linux kernel: from 5.17 before 5.17.14; from 5.18 before 5.18.3 — fixed in 5.17.14, 5.18.3

How to fix

Upgrade to a fixed version: Linux kernel 5.17.14, 5.18.3. Check the vendor advisory for mitigations.

References

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