Bug 1590215 (CVE-2018-12232)

Summary:	CVE-2018-12232 kernel: NULL pointer dereference if close and fchownat system calls share a socket file descriptor
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	airlied, aquini, bhu, blc, bskeggs, dhoward, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, 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, slawomir, steved, 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 NULL pointer dereference issue was found in the Linux kernel. If the close() and fchownat() system calls share a socket file descriptor as an argument, then the two calls can race and trigger a NULL pointer dereference leading to a system crash and a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-10 10:28:45 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:	1590216, 1590217, 1591837
Bug Blocks:	1590219

Description Andrej Nemec 2018-06-12 08:38:36 UTC

A NULL pointer dereference issue was found in the Linux kernel. If the close() and fchownat() system calls share a socket file descriptor as an argument, then the two calls can race and trigger a NULL pointer dereference leading to a system crash and a denial of service.

References:

https://lkml.org/lkml/2018/6/5/14

https://marc.info/?t=152817459500001&r=1&w=2

https://patchwork.ozlabs.org/patch/926519/

An upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6d8c50dcb029872b298eea68cc6209c866fd3e14

Comment 1 Andrej Nemec 2018-06-12 08:39:33 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1590216]

Comment 6 errata-xmlrpc 2018-10-30 09:01:56 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:2948 https://access.redhat.com/errata/RHSA-2018:2948