Bug 1404939 (CVE-2016-7914)

Summary:	CVE-2016-7914 kernel: assoc_array: don't call compare_object() on a node
Product:	[Other] Security Response	Reporter:	Vladis Dronov <vdronov>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	agordeev, aquini, arm-mgr, bhu, dhoward, esammons, fhrbata, gansalmon, iboverma, ichavero, itamar, jforbes, jkacur, jkastner, joelsmith, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, nmurray, pholasek, plougher, rt-maint, rvrbovsk, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	The assoc_array_insert_into_terminal_node() function in 'lib/assoc_array.c' in the Linux kernel before 4.5.3 does not check whether a slot is a leaf, which allows local users to obtain sensitive information from kernel memory or cause a denial of service (invalid pointer dereference and out-of-bounds read) via an application that uses associative-array data structures.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-12-15 20:57:21 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:	1340073, 1404942
Bug Blocks:	1395269

Description Vladis Dronov 2016-12-15 07:14:31 UTC

The assoc_array_insert_into_terminal_node() function in 'lib/assoc_array.c' in the Linux kernel before 4.5.3 does not check whether a slot is a leaf, which allows local users to obtain sensitive information from kernel memory or cause a denial of service (invalid pointer dereference and out-of-bounds read) via an application that uses associative-array data structures, as demonstrated by the keyutils test suite.

References:

http://source.android.com/security/bulletin/2016-11-01.html

https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-7914

Upstream patch:

https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=8d4a2ec1e0b41b0cf9a0c5cd4511da7f8e4f3de2

Comment 4 Vladis Dronov 2016-12-15 07:39:20 UTC

Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 and 6 as the code with the flaw is not present in the products listed.

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 7 and Red Hat Enterprise MRG-2 as the flaw was already fixed in the products listed.