Bug 1631045 (CVE-2018-9517)

Summary:	CVE-2018-9517 kernel: l2tp: Race condition between pppol2tp_session_create() and l2tp_eth_create()
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	abhgupta, airlied, aquini, bhu, blc, bskeggs, dbaker, dhoward, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, jforbes, jglisse, jkacur, john.j5live, jokerman, jonathan, josef, jross, jstancek, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, plougher, rt-maint, rvrbovsk, slawomir, steved, sthangav, trankin, vdronov, 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 race condition between pppol2tp_session_create() and l2tp_eth_create() in net/l2tp/l2tp_netlink.c was found in the Linux kernel. Calling l2tp_tunnel_find() may result in a new tunnel being created with tunnel id of a previously removed tunnel which wouldn't be protected by the reference counter.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-08-06 13:19:52 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:	1631046, 1631048, 1631049, 1637904, 1637905, 1637906
Bug Blocks:	1631047

Description Pedro Sampaio 2018-09-19 19:51:40 UTC

A race condition between pppol2tp_session_create() and l2tp_eth_create() in net/l2tp/l2tp_netlink.c in the Linux kernel. Calling l2tp_tunnel_find() may result in a new tunnel being created with tunnel id of a previous removed tunnel which wouldn't be protected by the reference counter.

An upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f026bc29a8e093edfbb2a77700454b285c97e8ad

Comment 1 Pedro Sampaio 2018-09-19 19:52:50 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1631046]

Comment 3 Justin M. Forbes 2018-09-20 12:59:26 UTC

This was fixed for Fedora with the 4.14 rebases.

Comment 7 errata-xmlrpc 2019-08-06 12:04:24 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2019:2029 https://access.redhat.com/errata/RHSA-2019:2029

Comment 8 errata-xmlrpc 2019-08-06 12:06:50 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2019:2043 https://access.redhat.com/errata/RHSA-2019:2043

Comment 9 Product Security DevOps Team 2019-08-06 13:19:52 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-2018-9517