CVE-2022-50546
Public on
Last Modified:
Description
An uninitialized variable flaw was found in the Linux kernel's ext4 filesystem in the inode eviction path. A local user can trigger this issue by creating filesystem operations that cause inode allocation to fail before the i_flags field is initialized, followed by inode cleanup that attempts to read the uninitialized field. This causes the kernel to access uninitialized memory, resulting in unpredictable behavior and denial of service through a kernel crash.
Statement
The ext4_alloc_inode function allocates memory for new inodes but fails to initialize the ei->i_flags field. When __ext4_new_inode encounters an error before setting i_flags and calls iput to clean up, the subsequent ext4_evict_inode function attempts to read the uninitialized i_flags value. This accesses undefined memory contents, triggering KMSAN (Kernel Memory Sanitizer) warnings and potentially causing kernel crashes or unpredictable behavior. The issue occurs during normal filesystem operations like mkdir or mknod when inode allocation fails partway through, which can happen under memory pressure or filesystem corruption. Any local user performing filesystem operations on ext4 volumes can potentially trigger this condition.
Additional Information
- This content is not included.Bugzilla 2402240: kernel: ext4: fix uninititialized value in 'ext4_evict_inode'
- Content from cwe.mitre.org is not included.CWE-908: Use of Uninitialized Resource
- FAQ: Frequently asked questions about CVE-2022-50546
- Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.
External References
Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2022-50546
Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2022-50546
Affected Packages and Issued Red Hat Security Errata
| Products / Services | Components | State | Errata |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Not affected | |
| Red Hat Enterprise Linux 6 | kernel | Out of support scope | |
| Red Hat Enterprise Linux 7 | kernel | Not affected | |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | |
| Red Hat Enterprise Linux 8 | kernel-rt | Fix deferred | |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2024:3138 |
| Red Hat Enterprise Linux 9 | kernel-rt | Fix deferred | |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2023:2458 |
Common Vulnerability Scoring System (CVSS) Score Details
Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).
| CVSS v3 Score Breakdown | Red Hat | NVD |
|---|---|---|
| CVSS v3 Base Score | 5.5 | 7.8 |
| Attack Vector | Local | Local |
| Attack Complexity | Low | Low |
| Privileges Required | Low | Low |
| User Interaction | None | None |
| Scope | Unchanged | Unchanged |
| Confidentiality Impact | None | High |
| Integrity Impact | None | High |
| Availability Impact | High | High |
CVSS v3 Vector
Red Hat CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
For more information, see https://access.redhat.com/solutions/762393.
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
- "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
- "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.
What can I do if my product is listed as "Will not fix"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
What can I do if my product is listed as "Fix deferred"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
- Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.
What is a mitigation?
I have a Red Hat product but it is not in the above list, is it affected?
Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?
My product is listed as "Out of Support Scope". What does this mean?
Not sure what something means? Check out our Security Glossary.