Bug 2221700 (CVE-2023-4134)

Summary:	CVE-2023-4134 kernel: cyttsp4_core: use-after-free in cyttsp4_watchdog_work()
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	CLOSED NOTABUG	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, tglozar, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 6.5-rc1	Doc Type:	If docs needed, set a value
Doc Text:	A use-after-free vulnerability was found in the cyttsp4_core driver in the Linux kernel. This issue occurs in the device cleanup routine due to a possible rearming of the watchdog_timer from the workqueue. This could allow a local user to crash the system, causing a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-08-03 15:01:50 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:	2221708, 2221710, 2228792
Bug Blocks:	2221670

Description Mauro Matteo Cascella 2023-07-10 15:29:43 UTC

From the upstream fix below: The watchdog_timer can schedule tx_timeout_task and watchdog_work can also arm watchdog_timer [..] Although del_timer_sync() and cancel_work_sync() are called in cyttsp4_remove(), the timer and workqueue could still be rearmed. As a result, the possible use after free bugs could happen.

Upstream commit:
https://github.com/torvalds/linux/commit/dbe836576f12743a7d2d170ad4ad4fd324c4d47a

Comment 2 Mauro Matteo Cascella 2023-08-03 09:49:56 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2228792]

Comment 3 Product Security DevOps Team 2023-08-03 15:01:46 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-2023-4134

Comment 4 Justin M. Forbes 2023-08-07 22:11:44 UTC

This was fixed for Fedora with the 6.4.4 stable kernel updates.