Bug 1518638 (CVE-2017-17053)

Summary:	CVE-2017-17053 kernel: Incorrect handling in arch/x86/include/asm/mmu_context.h:init_new_context function allowing use-after-free
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
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, airlied, ajax, aquini, bhu, blc, bskeggs, dhoward, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, jeremy, jforbes, jglisse, jkacur, john.j5live, jonathan, josef, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, plougher, rt-maint, rvrbovsk, skozina, steved, vdronov, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 4.13	Doc Type:	Bug Fix
Doc Text:	The init_new_context function in arch/x86/include/asm/mmu_context.h in the Linux kernel, before 4.12.10, does not correctly handle errors from LDT table allocation when forking a new process. This could allow a local attacker to achieve a use-after-free or possibly have unspecified other impact by running a specially crafted program.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 03:32:22 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:	1518642, 1543352, 1543353, 1543354
Bug Blocks:	1518639

Description Adam Mariš 2017-11-29 11:33:11 UTC

The init_new_context function in arch/x86/include/asm/mmu_context.h in the Linux kernel before 4.12.10 does not correctly handle errors from LDT table allocation when forking a new process, allowing a local attacker to achieve a use-after-free or possibly have unspecified other impact by running a specially crafted program.

An upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ccd5b3235180eef3cfec337df1c8554ab151b5cc

Comment 1 Adam Mariš 2017-11-29 11:45:26 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1518642]

Comment 2 Justin M. Forbes 2017-11-29 17:12:28 UTC

Fedora hasn't supported a 4.12.x kernel in quite some time. Current kernels are 4.13.16 across all supported releases.

Comment 6 Vladis Dronov 2018-02-08 10:33:12 UTC

Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6 and 7, its real-time kernel, Red Hat Enterprise MRG 2, Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE, as a code with the flaw is not present or is not built in the products listed.

Comment 7 errata-xmlrpc 2018-04-10 08:09:54 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:0676 https://access.redhat.com/errata/RHSA-2018:0676