Bug 2516764 (CVE-2026-74358)

Summary:	CVE-2026-74358 kernel: ext4: fix fast commit wait/wake bit mapping on 64-bit
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
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 `ext4` filesystem component of the Linux kernel. On 64-bit systems, an incorrect mapping of wait/wake bits during fast commits could lead to unexpected behavior. This issue, if triggered, may result in system instability or data integrity problems.	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 2026-08-15 06:32:19 UTC

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

ext4: fix fast commit wait/wake bit mapping on 64-bit

On 64-bit, ext4 dynamic inode states live in the upper half of i_flags,
and ext4_test_inode_state() applies the corresponding +32 offset.

The fast-commit wait and wake paths open-coded the wait key with the raw
EXT4_STATE_* value. Add small helpers for the state wait word and bit,
and use them for the FC_COMMITTING and FC_FLUSHING_DATA waits so the wait
key follows the same mapping as the state helpers.

Comment 1 gkamathe 2026-08-19 07:51:43 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081500-CVE-2026-74358-b2f1@gregkh/T