Bug 1805887 (CVE-2020-8992)

Summary:	CVE-2020-8992 kernel: soft lockup via a crafted journal size in ext4_protect_reserved_inode in fs/ext4/block_validity.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	acaringi, airlied, bhu, blc, brdeoliv, bskeggs, dhoward, dvlasenk, esammons, fhrbata, hdegoede, hkrzesin, iboverma, ichavero, itamar, jaeshin, jarodwilson, jeremy, jforbes, jglisse, jlelli, john.j5live, jonathan, josef, jross, jshortt, jstancek, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, masami256, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, qzhao, rkeshri, rt-maint, rvrbovsk, steved, williams
Target Milestone:	---	Keywords:	Reopened, Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	A vulnerability was found in ext4_protect_reserved_inode in the fs/ext4/block_validity.c function. This flaw allows an attacker to mount a crafted image with a large size inode journal, causing a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-05-20 09:15:21 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:	1805888
Bug Blocks:	1805889

Description Guilherme de Almeida Suckevicz 2020-02-21 17:06:10 UTC

A vulnerability was found in ext4_protect_reserved_inode in fs/ext4/block_validity.c. When a local attacker mounts a crafted image with a large size inode journal can cause a denial of service in form of a soft lockup problem.

Reference:
https://patchwork.ozlabs.org/patch/1236118/

Comment 1 Guilherme de Almeida Suckevicz 2020-02-21 17:07:04 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1805888]

Comment 2 Justin M. Forbes 2020-02-21 23:25:40 UTC

This was fixed for Fedora with the 5.5.5 kernel rebase for F31 and the 5.4.21 stable kernel update for F30.

Comment 5 Rohit Keshri 2020-04-14 09:02:30 UTC

Statement:

The affected code was not introduced into any kernel versions shipped with Red Hat Enterprise Linux making this vulnerable not applicable to these platforms.

Comment 6 Rohit Keshri 2020-04-14 09:02:40 UTC

Mitigation:

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread
installation base or stability.

Comment 8 Product Security DevOps Team 2020-04-14 10:31:49 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-2020-8992

Comment 11 Product Security DevOps Team 2020-05-20 09:15:21 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-2020-8992