Bug 2069736 (CVE-2022-2153)

Summary:	CVE-2022-2153 kernel: KVM: NULL pointer dereference in kvm_irq_delivery_to_apic_fast()
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, adscvr, airlied, alciregi, bhu, chwhite, crwood, ddepaula, dvlasenk, fpacheco, hdegoede, hkrzesin, hpa, jarod, jarodwilson, jburrell, jfaracco, jferlan, jforbes, jglisse, jlelli, joe.lawrence, jonathan, josef, jshortt, jstancek, jwboyer, jwyatt, kcarcia, kernel-maint, kernel-mgr, lgoncalv, linville, lzampier, masami256, mchehab, nmurray, ptalbert, qzhao, rvrbovsk, scweaver, steved, vkumar, walters, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 5.18	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the Linux kernel’s KVM when attempting to set a SynIC IRQ. This issue makes it possible for a misbehaving VMM to write to SYNIC/STIMER MSRs, causing a NULL pointer dereference. This flaw allows an unprivileged local attacker on the host to issue specific ioctl calls, causing a kernel oops condition that results in a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2067251, 2072549, 2074832, 2074835, 2099734, 2099735, 2099736, 2099737, 2099738
Bug Blocks:	2069747

Description Pedro Sampaio 2022-03-29 15:11:42 UTC

When KVM initialize a vCPU without create apic, the value of vcpu->arch.apic is NULL, then if we enter guest and let KVM call kvm_hv_process_stimers() in arch/x86/kvm/x86.c:9947, which doesn't check apic in the kernel. Process stimer will use apic finally so it will cause a null pointer dereference. This flaw allows a malicious user in a Local DOS condition.

References:

https://patchew.org/linux/20220325132140.25650-1-vkuznets@redhat.com/

Comment 3 Mauro Matteo Cascella 2022-06-14 09:52:32 UTC

Upstream commits:

- https://github.com/torvalds/linux/commit/7ec37d1cbe17d8189d9562178d8b29167fe1c31a
- https://github.com/torvalds/linux/commit/00b5f37189d24ac3ed46cb7f11742094778c46ce
- https://github.com/torvalds/linux/commit/b1e34d325397a33d97d845e312d7cf2a8b646b44

Comment 5 Mauro Matteo Cascella 2022-06-21 15:23:03 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2099734]

Comment 8 Justin M. Forbes 2022-06-21 15:49:19 UTC

This was fixed for Fedora with the 5.16.19 stable kernel updates.

Comment 13 Mauro Matteo Cascella 2023-02-21 17:12:17 UTC

This issue was fixed upstream in version 5.18. The kernel packages as shipped in following Red Hat products were previously updated to a version that contains the fix via the following errata:

kernel in Red Hat Enterprise Linux 8
https://access.redhat.com/errata/RHSA-2022:7683

kernel-rt in Red Hat Enterprise Linux 8
https://access.redhat.com/errata/RHSA-2022:7444

kernel in Red Hat Enterprise Linux 9
https://access.redhat.com/errata/RHSA-2022:8267

kernel-rt in Red Hat Enterprise Linux 9
https://access.redhat.com/errata/RHSA-2022:7933