Bug 2221501 (CVE-2023-3106)

Summary:	CVE-2023-3106 kernel: Netlink socket crash (null pointer deref) in netlink_dump function
Product:	[Other] Security Response	Reporter:	Alex <allarkin>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, allarkin, bhu, chwhite, crwood, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, security-response-team, tglozar, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 4.8-rc7	Doc Type:	If docs needed, set a value
Doc Text:	A NULL pointer dereference vulnerability was found in netlink_dump. This issue can occur when the Netlink socket receives the message(sendmsg) for the XFRM_MSG_GETSA, XFRM_MSG_GETPOLICY type message, and the DUMP flag is set and can cause a denial of service or possibly another unspecified impact. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is unlikely.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-07-12 11:39:41 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:	2221502, 2221503, 2222176
Bug Blocks:	2211870

Description Alex 2023-07-09 14:55:38 UTC

A flaw in the Linux Kernel found in netlink_dump. When the Netlink socket receives the message(sendmsg), for the XFRM_MSG_GETSA, XFRM_MSG_GETPOLICY type message and the DUMP flag is set, it will enter the netlink_dump function for processing. When sending data to the socket multiple times, it will make sk->sk_rmem_alloc continues to accumulate, and eventually atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf will be judged as True, skipping the initialization of netlink_callback->args.

Reference:
https://github.com/torvalds/linux/commit/1ba5bf993c6a3142e18e68ea6452b347f9cb5635

Comment 4 Alex 2023-07-12 07:04:02 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2222176]

Comment 6 Product Security DevOps Team 2023-07-12 11:39:38 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-2023-3106

Comment 7 Justin M. Forbes 2023-07-18 18:33:34 UTC

This was fixed for Fedora with 4.8 kernel updates in 2016.