Bug 1560968 (CVE-2017-18249)

Summary:	CVE-2017-18249 kernel: Race condition in fs/f2fs/node.c:add_free_nid() function allows local users to cause denial of service
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	airlied, ajax, aquini, bhu, blc, bskeggs, dhoward, esammons, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, jforbes, jglisse, jkacur, john.j5live, jonathan, josef, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, lwang, matt, mchehab, mcressma, mguzik, mjg59, mlangsdo, nmurray, plougher, pmatouse, rt-maint, rvrbovsk, skozina, steved, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 4.12	Doc Type:	If docs needed, set a value
Doc Text:	The add_free_nid function in fs/f2fs/node.c in the Linux kernel, before 4.12, does not properly track an allocated nid. This allows local users to cause a denial of service (race condition) or possibly have unspecified other impacts via concurrent threads.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-04-05 12:22:30 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:	1563517
Bug Blocks:	1560970

Description Adam Mariš 2018-03-27 11:30:07 UTC

The add_free_nid function in fs/f2fs/node.c in the Linux kernel before 4.12 does not properly track an allocated nid, which allows local users to cause a denial of service (race condition) or possibly have unspecified other impact via concurrent threads.

Upstream patch:

https://github.com/torvalds/linux/commit/30a61ddf8117c26ac5b295e1233eaa9629a94ca3

Comment 1 Wade Mealing 2018-04-04 04:48:02 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1563517]

Comment 4 Justin M. Forbes 2018-04-04 12:51:07 UTC

This was fixed for Fedora with the 4.12 kernel