Bug 2173626 (CVE-2022-20566)

Summary:	CVE-2022-20566 kernel: possible use after free due to improper locking in l2cap_chan_put of l2cap_core
Product:	[Other] Security Response	Reporter:	Alex <allarkin>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, arachman, 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, lveyde, lzampier, michal.skrivanek, mperina, nmurray, ptalbert, qzhao, rogbas, rvrbovsk, scweaver, vkumar, walters, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	Linux kernel 6.0-rc1	Doc Type:	If docs needed, set a value
Doc Text:	A use-after-free flaw was found in the Linux kernel's Bluetooth functionality. A user could trigger a race condition while closing the connection. This issue may allow a local user to crash or potentially escalate their privileges on the system.	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:	2173627, 2174433, 2174434, 2174435
Bug Blocks:	2173148

Description Alex 2023-02-27 14:40:23 UTC

A flaw found in the Linux Kernel bluetooth. In l2cap_chan_put of l2cap_core, there is a possible use after free due to improper locking. Happens during sock_close() when being called l2cap_chan_put(). This could lead to local escalation of privilege.
The issue actual if patch ef191aded58c5 "Bluetooth: Restore locking semantics when looking up L2CAP channels" already applied.

Reference:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d0be8347c623e0ac4202a1d4e0373882821f56b0

Comment 1 Alex 2023-02-27 14:40:50 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2173627]

Comment 4 Justin M. Forbes 2023-03-01 19:57:13 UTC

This was fixed for Fedora with the 5.18.16 stable kernel update.