Bug 1801616 (CVE-2019-15791)

Summary:	CVE-2019-15791 kernel: reference count underflow was discovered in shiftfs implementation causing dos
Product:	[Other] Security Response	Reporter:	Dhananjay Arunesh <darunesh>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, airlied, bhu, blc, brdeoliv, bskeggs, dhoward, dvlasenk, esammons, fhrbata, hdegoede, hkrzesin, iboverma, ichavero, itamar, 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, rt-maint, rvrbovsk, steved, williams
Target Milestone:	---	Keywords:	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 Linux kernel. A reference count underflow was discovered in the shiftfs implementation which could be used to cause a denial of service (system crash) or possibly execute arbitrary code. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-03-31 05:47:22 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:	1801617
Bug Blocks:	1801619

Description Dhananjay Arunesh 2020-02-11 11:24:48 UTC

A vulnerability was found in Linux Kernel, where a reference count underflow was discovered in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code.

Reference:
http://people.canonical.com/~ubuntu-security/cve/2019/CVE-2019-15791.html

Comment 1 Dhananjay Arunesh 2020-02-11 11:25:47 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1801617]

Comment 2 Justin M. Forbes 2020-02-11 15:52:50 UTC

Shiftfs is not upstream, and is currently an Ubuntu specific patch set.  This has never impacted any Fedora products.

Comment 3 Dave Baker 2020-03-10 13:57:50 UTC

The fs/shiftfs.c file affected by this flaw is also not present in RHEL.

Comment 4 Wade Mealing 2020-03-31 05:46:35 UTC

Statement:

No current shipping products include the code necessary to fix this issue.

Comment 5 Wade Mealing 2020-03-31 05:47:04 UTC

Mitigation:

Mitigation of this flaw is not necessary on Red Hat Enterprise Linux and layered products.