Bug 1929546 (CVE-2021-26933)

Summary: CVE-2021-26933 xen: arm: The cache may not be cleaned for newly allocated scrubbed pages
Product: [Other] Security Response Reporter: msiddiqu
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED UPSTREAM QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: jforbes, m.a.young, robinlee.sysu
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Last Closed: 2021-02-17 07:02:20 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1929547    
Bug Blocks: 1924847    

Description msiddiqu 2021-02-17 06:16:54 UTC
On Arm, a guest is allowed to control whether memory access bypass the
cache.  This means that Xen needs to ensure that all writes (such as
the ones during scrubbing) have reached memory before handing over the
page to a guest.

External References:

https://xenbits.xen.org/xsa/advisory-364.html

Comment 1 msiddiqu 2021-02-17 06:17:12 UTC
Created xen tracking bugs for this issue:

Affects: fedora-all [bug 1929547]

Comment 2 Product Security DevOps Team 2021-02-17 07:02:20 UTC
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.