Bug 1834862 (CVE-2020-12771)

Summary:	CVE-2020-12771 kernel: deadlock if a coalescing operation fails in btree_gc_coalesce function in drivers/md/bcache/btree.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:	low	Docs Contact:
Priority:	low
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, 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:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-05-14 12:24:58 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:	1834865
Bug Blocks:	1834864

Description Guilherme de Almeida Suckevicz 2020-05-12 14:44:56 UTC

An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails.

Reference:
https://lkml.org/lkml/2020/4/26/87

Comment 1 Guilherme de Almeida Suckevicz 2020-05-12 14:46:47 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1834865]

Comment 3 Justin M. Forbes 2020-10-08 18:56:03 UTC

This was fixed for Fedora with the 5.7.6 stable kernel updates.