Bug 2173973 (CVE-2023-1095)

Summary:	CVE-2023-1095 kernel: netfilter: NULL pointer dereference in nf_tables due to zeroed list head
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, bhu, chwhite, crwood, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, fhrbata, hkrzesin, jarod, jburrell, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rvrbovsk, scweaver, tyberry, vkumar, walters, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 6.0-rc1	Doc Type:	If docs needed, set a value
Doc Text:	A NULL pointer dereference flaw was found in the Linux kernel’s netfilter subsystem. The issue could occur due to an error in nf_tables_updtable while freeing a transaction object not placed on the list head. This flaw allows a local, unprivileged user to crash the system, resulting in a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2072549, 2121393, 2134371, 2173999, 2174000, 2174001, 2174002
Bug Blocks:	2154244

Description Mauro Matteo Cascella 2023-02-28 14:55:06 UTC

In nf_tables_updtable, if nf_tables_table_enable returns an error, nft_trans_destroy is called to free the transaction object. nft_trans_destroy() calls list_del(), but the transaction was never placed on a list -- the list head is all zeroes, this results in a NULL pointer dereference.

Upstream patch & commit:
https://lore.kernel.org/netfilter-devel/20220809163402.20227-1-fw@strlen.de/
https://github.com/torvalds/linux/commit/580077855a40741cf511766129702d97ff02f4d9

Comment 4 Mauro Matteo Cascella 2023-02-28 16:36:29 UTC

This issue was fixed upstream in version 6.0. The kernel packages as shipped in Red Hat Enterprise Linux 8 and 9 were previously updated to a version that contains the fix via the following errata:

kernel in Red Hat Enterprise Linux 8
https://access.redhat.com/errata/RHSA-2023:2951

kernel-rt in Red Hat Enterprise Linux 8
https://access.redhat.com/errata/RHSA-2023:2736

kernel in Red Hat Enterprise Linux 9
https://access.redhat.com/errata/RHSA-2022:8267

kernel-rt in Red Hat Enterprise Linux 9
https://access.redhat.com/errata/RHSA-2022:7933

Comment 10 errata-xmlrpc 2023-10-10 16:24:09 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.4 Telecommunications Update Service

Via RHSA-2023:5628 https://access.redhat.com/errata/RHSA-2023:5628

Comment 11 errata-xmlrpc 2023-10-10 16:26:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Extended Update Support

Via RHSA-2023:5627 https://access.redhat.com/errata/RHSA-2023:5627

Comment 13 errata-xmlrpc 2023-11-08 10:57:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.1 Update Services for SAP Solutions

Via RHSA-2023:6813 https://access.redhat.com/errata/RHSA-2023:6813