Bug 2300709 (CVE-2024-42094)

Summary: CVE-2024-42094 kernel: net/iucv: Avoid explicit cpumask var allocation on stack
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, rhel-process-autobot, vkumar, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: kernel 4.19.317, kernel 5.4.279, kernel 5.10.221, kernel 5.15.162, kernel 6.1.97, kernel 6.6.37, kernel 6.9.8, kernel 6.10 Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in the Linux kernel's net/iucv component. This vulnerability arises when a specific kernel configuration (CONFIG_CPUMASK_OFFSTACK=y) is enabled, allowing for explicit allocation of cpumask variables directly on the system's memory stack. An attacker could exploit this to trigger a stack overflow, potentially leading to a Denial of Service (DoS) condition, which would make the system unavailable.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2301749    
Bug Blocks:    

Description OSIDB Bzimport 2024-07-29 18:20:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net/iucv: Avoid explicit cpumask var allocation on stack

For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask
variable on stack is not recommended since it can cause potential stack
overflow.

Instead, kernel code should always use *cpumask_var API(s) to allocate
cpumask var in config-neutral way, leaving allocation strategy to
CONFIG_CPUMASK_OFFSTACK.

Use *cpumask_var API(s) to address it.
Comment 1 Mauro Matteo Cascella 2024-07-30 17:42:01 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024072911-CVE-2024-42094-135f@gregkh/T
Comment 2 Mauro Matteo Cascella 2024-07-30 17:42:21 UTC 
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2301749]
Comment 11 errata-xmlrpc 2024-09-24 02:35:19 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2024:7000 https://access.redhat.com/errata/RHSA-2024:7000
Comment 12 errata-xmlrpc 2025-09-11 06:36:00 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:15668 https://access.redhat.com/errata/RHSA-2025:15668