CVE-2024-49957: In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix null-ptr-deref when journal load failed. During the mounting process,...

Description

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix null-ptr-deref when journal load failed. During the mounting process, if journal_reset() fails because of too short journal, then lead to jbd2_journal_load() fails with NULL j_sb_buffer. Subsequently, ocfs2_journal_shutdown() calls jbd2_journal_flush()->jbd2_cleanup_journal_tail()-> __jbd2_update_log_tail()->jbd2_journal_update_sb_log_tail() ->lock_buffer(journal->j_sb_buffer), resulting in a null-pointer dereference error. To resolve this issue, we should check the JBD2_LOADED flag to ensure the journal was properly loaded. Additionally, use journal instead of osb->journal directly to simplify the code.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.25%

16.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-476

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	>= 2.6.32, < 5.10.227
Linux	Linux Kernel	>= 5.11, < 5.15.168
Linux	Linux Kernel	>= 5.16, < 6.1.113
Linux	Linux Kernel	>= 6.2, < 6.6.55
Linux	Linux Kernel	>= 6.7, < 6.10.14
Linux	Linux Kernel	>= 6.11, < 6.11.3

References

Timeline

Published: Oct 21, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2024-49957?

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix null-ptr-deref when journal load failed. During the mounting process, if journal_reset() fails because of too short journal, then lead to jbd2_journal_load() fails with NULL j_sb_buffer. Subsequently, ocfs2_journal_shutdown() calls jbd2_journal_flush()->jbd2_cleanup_journal_tail()-> __jbd2_update_log_tail()->jbd2_journal_update_sb_log_tail() ->lock_buffer(journal->j_sb_buffer), resulting in a null-pointer dereference error. To resolve this issue, we should check the JBD2_LOADED flag to ensure the journal was properly loaded. Additionally, use journal instead of osb->journal directly to simplify the code.

How severe is CVE-2024-49957?

CVE-2024-49957 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.

How do I fix CVE-2024-49957?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.