Bug 1888886 (CVE-2020-27152)

Summary: CVE-2020-27152 Kernel: KVM: host stack overflow due to lazy update IOAPIC
Product: [Other] Security Response Reporter: Prasad Pandit <ppandit>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: acaringi, airlied, bhu, blc, bmasney, brdeoliv, bskeggs, dhoward, dvlasenk, esammons, fhrbata, hdegoede, hkrzesin, iboverma, ichavero, itamar, jarodwilson, jeremy, jforbes, jglisse, jlelli, john.j5live, jonathan, josef, jross, jshortt, jstancek, jwboyer, kcarcia, kernel-maint, kernel-mgr, lgoncalv, linville, masami256, mchehab, mcressma, mjg59, mlangsdo, nmurray, pbonzini, ptalbert, qzhao, rt-maint, rvrbovsk, steved, walters, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Linux 5.10 Doc Type: If docs needed, set a value
Doc Text:
A stack overflow flaw via an infinite loop condition issue was found in the KVM hypervisor of the Linux kernel. This flaw occurs while processing interrupts because the IRQ state is erroneously set. This flaw allows a guest user to crash the host kernel, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Story Points: ---
Clone Of: Environment:
Last Closed: 2021-04-06 17:35:14 UTC 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: 1867373, 1882793, 1888887, 1888888, 1906438, 1906439    
Bug Blocks: 1888749    

Description Prasad Pandit 2020-10-16 06:16:25 UTC
A stack overflow via an infinite loop condition issue was found in the KVM hypervisor of the Linux kernel. It could occur while processing interrupts because irq state is erroneously set. A guest user may use this flaw to crash the host kernel resulting in DoS scenario.

Upstream patch:
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  -> https://git.kernel.org/linus/77377064c3a94911339f13ce113b3abf265e06da

Reference:
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  -> https://www.openwall.com/lists/oss-security/2020/11/03/1

Comment 2 Prasad Pandit 2020-10-16 06:17:15 UTC
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1888887]

Comment 5 RaTasha Tillery-Smith 2020-10-20 15:25:03 UTC
Mitigation:

Disabling APICV by setting the kvm_intel.enable_apicv=0 parameter helps to avoid this situation.

Comment 6 Paolo Bonzini 2020-10-24 09:08:10 UTC
Patch sent upstream.

Comment 9 Prasad Pandit 2020-11-03 11:04:28 UTC
Statement:

This issue does not affect the versions of the kernel package as shipped with Red Hat Enterprise Linux 5, 6, 7 and Red Hat Enterprise MRG 2.
This issue affects the version of the kernel package as shipped with Red Hat Enterprise Linux 8. Future kernel updates for Red Hat Enterprise Linux 8  may address this issue.

Comment 10 Justin M. Forbes 2020-11-04 16:27:21 UTC
This was fixed for Fedora with the 5.8.17 stable kernel update.

Comment 12 errata-xmlrpc 2021-04-06 13:58:05 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1081 https://access.redhat.com/errata/RHSA-2021:1081

Comment 13 errata-xmlrpc 2021-04-06 14:17:00 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1093 https://access.redhat.com/errata/RHSA-2021:1093

Comment 14 Product Security DevOps Team 2021-04-06 17:35:14 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2020-27152