Bug 1842547 (CVE-2019-20806)

Summary:	CVE-2019-20806 kernel: NULL pointer dereference in tw5864_handle_frame function in drivers/media/pci/tw5864/tw5864-video.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, airlied, bhu, blc, bmasney, brdeoliv, bskeggs, dhoward, dvlasenk, esammons, fhrbata, hdegoede, hkrzesin, iboverma, ichavero, itamar, jarodwilson, jeremy, jforbes, jglisse, jlelli, john.j5live, jonathan, josef, jross, jshortt, jstancek, jwboyer, kcarcia, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, masami256, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, ptalbert, qzhao, rkeshri, rt-maint, rvrbovsk, steved, 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:	A NULL pointer dereference flaw was found in tw5864_handle_frame function in drivers/media/pci/tw5864/tw5864-video.c in the TW5864 Series Video media driver. The pointer 'vb' is assigned, but not validated before its use, and can lead to a denial of service. This flaw allows a local attacker with special user or root privileges to crash the system or leak internal kernel information.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-06-10 23:20:28 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:	1842548
Bug Blocks:	1842549

Description Guilherme de Almeida Suckevicz 2020-06-01 14:05:56 UTC

A NULL pointer dereference flaw was found in tw5864_handle_frame function in drivers/media/pci/tw5864/tw5864-video.c in TW5864 Series Video media driver.  Here a pointer 'vb' assigned but not validated before its use can lead to a denial of service (DoS) problem. This flaw could allow a local attacker with special user privilege (or root) to crash the system or leak internal kernel information.

Reference and upstream commit:
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.2
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2e7682ebfc750177a4944eeb56e97a3f05734528

Comment 1 Guilherme de Almeida Suckevicz 2020-06-01 14:06:43 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1842548]

Comment 2 Justin M. Forbes 2020-06-01 14:16:39 UTC

This was fixed for Fedora in the 5.2 stable kernel rebases.

Comment 5 Rohit Keshri 2020-06-05 12:50:04 UTC

Mitigation:

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Comment 8 Product Security DevOps Team 2020-06-10 23:20:28 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2019-20806

Comment 9 RaTasha Tillery-Smith 2020-06-15 14:59:24 UTC

Statement:

There was not a shipped kernel version that was seen to be affected by this problem. These files are not built into the source code.