Bug 2482058 (CVE-2026-45953)

Summary:	CVE-2026-45953 kernel: md/raid5: fix IO hang with degraded array with llbitmap
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's RAID5 module. When a low-level bitmap (llbitmap) bit state is unwritten in a degraded array, a missing check during write operations can cause the system to enter an infinite loop. This can lead to an I/O hang, effectively resulting in a Denial of Service (DoS) for the affected system.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-05-27 15:09:18 UTC

In the Linux kernel, the following vulnerability has been resolved:

md/raid5: fix IO hang with degraded array with llbitmap

When llbitmap bit state is still unwritten, any new write should force
rcw, as bitmap_ops->blocks_synced() is checked in handle_stripe_dirtying().
However, later the same check is missing in need_this_block(), causing
stripe to deadloop during handling because handle_stripe() will decide
to go to handle_stripe_fill(), meanwhile need_this_block() always return
0 and nothing is handled.

Comment 1 Keith Grant 2026-05-27 23:39:10 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052732-CVE-2026-45953-7e84@gregkh/T