Bug 1286971 (CVE-2015-8701)

Summary:	CVE-2015-8701 Qemu: net: rocker: stack buffer overflow(off-by-one) in tx_consume routine
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:	abaron, apevec, areis, ayoung, carnil, chrisw, dallan, gkotton, jen, jschluet, knoel, lhh, lpeer, markmc, mkenneth, mrezanin, mst, osoukup, pbonzini, ppandit, rbryant, sclewis, security-response-team, slong, srevivo, tdecacqu
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	An off-by-one vulnerability was discovered in the QEMU emulator built with Rocker-switch emulation support. The flaw occurred when processing transmit(tx) descriptors in the 'tx_consume' routine, if a descriptor had more than the allowed fragments (ROCKER_TX_FRAGS_MAX=16).	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 02:45:58 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:	1293720
Bug Blocks:	1286975

Description Adam Mariš 2015-12-01 09:27:41 UTC

Qemu emulator built with the Rocker switch emulation support is vulnerable to an off-by-one error. It happens while processing transmit(tx) descriptors in 'tx_consume' routine, if a descriptor was to have more than allowed (ROCKER_TX_FRAGS_MAX=16)fragments.

A privileged user inside guest could use this flaw to cause memory leakage on the host or crash the Qemu process instance resulting in DoS issue.

Upstream patch:
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  -> https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg04629.html

Reference:
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  -> http://www.openwall.com/lists/oss-security/2015/12/29/1

Comment 2 Prasad Pandit 2015-12-22 19:37:11 UTC

Statement: 

This issue does not affect the versions of the kvm and xen packages as shipped with Red Hat Enterprise Linux 5.

This issue does not affect the versions of the qemu-kvm packages as shipped with Red Hat Enterprise Linux 6, and the Red Hat Enterprise Linux 6 based versions of qemu-kvm-rhev packages as shipped with Red Hat Enterprise Virtualization 3.

This issue does not affect the versions of the qemu-kvm packages as shipped with Red Hat Enterprise Linux 7.

This issue does not affect the Red Hat Enterprise Linux 7 based versions of the qemu-kvm-rhev packages as shipped with Red Hat Enterprise Virtualization 3.

Comment 3 Prasad Pandit 2015-12-22 20:26:14 UTC

Created qemu tracking bugs for this issue:

Affects: fedora-all [bug 1293720]

Comment 4 Fedora Update System 2016-01-24 03:26:42 UTC

qemu-2.4.1-6.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.