Bug 1428485 (CVE-2017-6345)

Summary:	CVE-2017-6345 kernel: llc: skb->sk set without skb->destructor
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	agordeev, aquini, bhu, dhoward, esammons, fhrbata, gansalmon, iboverma, ichavero, itamar, jforbes, jkacur, jkastner, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, nmurray, pholasek, plougher, rt-maint, rvrbovsk, vdronov, vvs, williams, yozone
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	The LLC subsystem in the Linux kernel does not ensure that a certain destructor exists in required circumstances, which allows local users to cause a denial of service (BUG_ON) or possibly have unspecified other impact via crafted system calls.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-03-14 14:20:30 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:
Bug Blocks:	1428493

Description Andrej Nemec 2017-03-02 16:43:32 UTC

The LLC subsystem in the Linux kernel does not ensure that a certain destructor exists in required circumstances, which allows local users to cause a denial of service (BUG_ON) or possibly have unspecified other impact via crafted system calls.

Upstream patch:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8b74d439e1697110c5e5c600643e823eb1dd0762

References:

http://seclists.org/oss-sec/2017/q1/527

Comment 1 Vasily Averin 2017-03-03 08:42:49 UTC

wrong reference to oss-sec.
correct one is
http://seclists.org/oss-sec/2017/q1/527

Comment 2 Andrej Nemec 2017-03-03 08:52:27 UTC

(In reply to Vasily Averin from comment #1)
> wrong reference to oss-sec.
> correct one is
> http://seclists.org/oss-sec/2017/q1/527

Thanks, you are obviously right. Updated.

Comment 3 Justin M. Forbes 2017-03-06 15:31:46 UTC

This was fixed for Fedora in the 4.9.13 kernels.

Comment 6 Vladis Dronov 2017-03-14 14:20:30 UTC

Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6, 7 and MRG-2, as the kernel module 'llc2.ko' with this security flaw is not shipped with the products listed.