Bug 2134370 (CVE-2022-4127)

Summary:	CVE-2022-4127 kernel: io_uring: NULL pointer dereference in io_files_update_with_index_alloc
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, bhu, brdeoliv, chwhite, crwood, ddepaula, debarbos, dhoward, dvlasenk, ezulian, fhrbata, hkrzesin, jarod, jburrell, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rvrbovsk, scweaver, tyberry, vkumar, walters, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 5.19	Doc Type:	If docs needed, set a value
Doc Text:	A NULL pointer dereference issue was discovered in the Linux kernel in io_files_update_with_index_alloc. A local user could use this flaw to potentially crash the system causing a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-11-29 18:57:41 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:	2145155
Bug Blocks:	2121459

Description Mauro Matteo Cascella 2022-10-13 09:35:18 UTC

If IORING_FILE_INDEX_ALLOC is set asking for an allocated slot, the helper doesn't check if we actually have a file table or not, possibly leading to a NULL pointer dereference.

Upstream patch & commit:
https://lore.kernel.org/all/d5a19c1e-9968-e22e-5917-c3139c5e7e89@kernel.dk/
https://github.com/torvalds/linux/commit/d785a773bed966a75ca1f11d108ae1897189975b

Comment 2 Mauro Matteo Cascella 2022-11-23 11:27:34 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2145155]

Comment 3 Product Security DevOps Team 2022-11-29 18:57:39 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-2022-4127

Comment 4 Justin M. Forbes 2022-11-30 20:03:01 UTC

This was fixed for Fedora with the 5.19 stable kernel rebases.