Bug 2033723 (CVE-2021-0961)

Summary:	CVE-2021-0961 kernel: there is a possible way to read kernel memory due to uninitialized data in quota_proc_write() in xt_quota2.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:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, adscvr, airlied, alciregi, bdettelb, bhu, blc, brdeoliv, bskeggs, chwhite, crwood, dhoward, dvlasenk, fhrbata, fpacheco, hdegoede, hkrzesin, jarod, jarodwilson, jburrell, jeremy, jfaracco, jforbes, jglisse, jlelli, jonathan, josef, jshortt, jstancek, jwboyer, kcarcia, kernel-maint, kernel-mgr, lgoncalv, linville, lzampier, masami256, mchehab, mlangsdo, nmurray, ptalbert, qzhao, rvrbovsk, scweaver, steved, vkumar, walters, 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:	An uninitialized data read flaw in the Linux kernel Android enhanced xt_quota that can count upwards and in packets functionality was found in the way user calls function quota_proc_write. A local user could use this flaw to get unauthorized data access.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-12-23 14:52:56 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:	2033724
Bug Blocks:	2033725

Description Guilherme de Almeida Suckevicz 2021-12-17 17:18:01 UTC

In quota_proc_write of xt_quota2.c, there is a possible way to read kernel memory due to uninitialized data. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-196046570References: Upstream kernel

References:
https://source.android.com/security/bulletin/2021-12-01

Upstream patches:
https://android.googlesource.com/kernel/common/+/e113eb454e92
https://android.googlesource.com/kernel/common/+/60a4c35570d9
https://android.googlesource.com/kernel/common/+/4b05a506bda0

Comment 1 Guilherme de Almeida Suckevicz 2021-12-17 17:18:55 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2033724]

Comment 2 Justin M. Forbes 2021-12-21 14:46:51 UTC

xt_quota2.c is an android implementatation, not in the upstream kernel tree.  This code does not appear in the Fedora kernel at all.