Bug 1481146 (CVE-2017-10662)

Summary:	CVE-2017-10662 kernel: Missing sanity check for segment count in f2fs
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	agordeev, aquini, bhu, blc, dhoward, esammons, fhrbata, gansalmon, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jforbes, jkacur, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, mlangsdo, nmurray, pholasek, plougher, rt-maint, rvrbovsk, slawomir, vdronov, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	It was found that the sanity_check_raw_super() function in 'fs/f2fs/super.c' file in the Linux kernel before version 4.12-rc1 does not validate the f2fs filesystem segment count. This allows an unprivileged local user to cause a system panic and DoS. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-08-27 13:34:35 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:	1481154

Description Adam Mariš 2017-08-14 08:35:00 UTC

In was found that the sanity_check_raw_super() function in 'fs/f2fs/super.c' file in the Linux kernel before 4.12-rc1 does not validate the f2fs filesystem segment count, which allows an unprivileged local user to cause a system panic and DoS. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely.

References:

https://source.android.com/security/bulletin/2017-08-01#kernel-components

Upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b9dd46188edc2f0d1f37328637860bb65a771124

Comment 3 Vladis Dronov 2017-08-27 13:34:35 UTC

Statement:

This issue does not affect the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 5, 6, 7 and Red Hat Enterprise MRG 2 as the code with the flaw is not built and shipped with the products listed.