Bug 1285213 (CVE-2015-8345)

Summary:	CVE-2015-8345 Qemu: net: eepro100: infinite loop in processing command block list
Product:	[Other] Security Response	Reporter:	Prasad Pandit <ppandit>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	abaron, ailan, amit.shah, apevec, areis, ayoung, berrange, cfergeau, chrisw, cvsbot-xmlrpc, dallan, drjones, dwmw2, gkotton, imammedo, itamar, jen, jforbes, jjoyce, jschluet, kbasil, knoel, lhh, lpeer, markmc, m.a.young, mkenneth, mrezanin, mst, pbonzini, rbryant, rjones, rkrcmar, sclewis, slong, srevivo, tdecacqu, virt-maint, virt-maint, vkuznets, xen-maint
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	An infinite-loop flaw was discovered in the QEMU emulator built with i8255x (PRO100) emulation support. When processing a chain of commands located in the Command Block List(CBL), each Command Block(CB) points to the next command in the list. If the link to the next CB pointed to the same block or if there was a closed loop in the chain, an infinite loop would execute the same command over and over again. A privileged user inside the guest could use this flaw to crash the QEMU instance, resulting in denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 02:45:52 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:	1285214, 1285215
Bug Blocks:	1257953

Description Prasad Pandit 2015-11-25 08:49:21 UTC

Qemu emulator built with the i8255x (PRO100) emulation support is vulnerable
to an infinite loop issue. It could occur while processing a chain of commands
located in the Command Block List(CBL). Each Command Block(CB) points to the
next command in the list. An infinite loop unfolds if the link to the next
CB points to the same block or there is a closed loop in the chain.

A privileged(CAP_SYS_RAWIO) user inside guest could use this flaw to crash
the Qemu instance resulting in DoS.

Upstream patch:
---------------
  -> https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg03911.html

Reference:
----------
  -> http://www.openwall.com/lists/oss-security/2015/11/25/11

Comment 1 Prasad Pandit 2015-11-25 08:50:55 UTC

Created xen tracking bugs for this issue:

Affects: fedora-all [bug 1285215]

Comment 2 Prasad Pandit 2015-11-25 08:51:11 UTC

Created qemu tracking bugs for this issue:

Affects: fedora-all [bug 1285214]

Comment 3 Prasad Pandit 2015-11-25 08:58:13 UTC

Acknowledgements:

This issue was discovered by Qinghao Tang of QIHU 360 Marvel Team.

Comment 4 Prasad Pandit 2015-11-25 09:03:06 UTC

Statement: 

This issue affects the kvm package as shipped with Red Hat Enterprise Linux 5.

This issue affects the versions of the qemu-kvm packages as shipped with Red Hat Enterprise Linux 6 and 7.

This issue affects the Red Hat Enterprise Linux 6 based versions of qemu-kvm-rhev packages as shipped with Red Hat Enterprise Virtualization 3. 

This issue affects the Red Hat Enterprise Linux 7 based versions of the qemu-kvm-rhev packages as shipped with Red Hat Enterprise Virtualization 3.

This has been rated as having Moderate 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/

Comment 6 Fedora Update System 2015-12-17 07:25:16 UTC

xen-4.5.2-5.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 7 Fedora Update System 2015-12-17 07:29:44 UTC

qemu-2.4.1-2.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 8 Fedora Update System 2015-12-20 00:21:46 UTC

xen-4.5.2-5.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.