Bug 1478018 (CVE-2017-14156)

Summary:	CVE-2017-14156 kernel: driver/video/fbdev/aty/atyfb_base.c: atyfb_ioctl() stack infoleak
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	agordeev, aquini, bhu, dhoward, esammons, fhrbata, gansalmon, hwkernel-mgr, iboverma, ichavero, itamar, jforbes, jkacur, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, 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:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-08-29 14:21:05 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:	1478019, 1478025, 1478026, 1478027, 1478028, 1478029, 1478030, 1478031, 1478032
Bug Blocks:	1478065

Description Pedro Sampaio 2017-08-03 13:08:30 UTC

In atyfb_ioctl() structure atyclk is copied to userland with padding bytes after
"vclk_post_div" field unitialized. It leads to leaking of contents of kernel stack memory. We have to initialize them to zero. Or it will allows local users to obtain potentially sensitive information from kernel stack memory by reading a copy of this structure.

References:

http://seclists.org/oss-sec/2017/q3/220

https://marc.info/?t=150401465500002&r=1&w=2

Suggested patch:

https://github.com/torvalds/linux/pull/441

https://marc.info/?l=linux-fbdev&m=150401461113305&w=2

Comment 1 Pedro Sampaio 2017-08-03 13:10:18 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1478019]

Comment 3 Justin M. Forbes 2017-08-03 13:28:24 UTC

# CONFIG_FB_ATY is not set

We don't enable this driver in fedora

Comment 4 Vladis Dronov 2017-08-29 10:44:28 UTC

Statement:

This issue does not affect the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 5 and 7 as the code with the flaw is not present in the products listed.

This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 6 and MRG-2. This has been rated as having Low security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.