Bug 2535142 (CVE-2026-89838)

Summary:	CVE-2026-89838 kernel: f2fs: limit recovery filename logging to stored length
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:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, 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 F2FS (Flash-Friendly File System) component. This vulnerability occurs during recovery filename logging when a filename of 255 bytes is processed. Due to improper handling of the filename buffer, which is not null-terminated, the system can read past the intended buffer into subsequent inode fields. This could lead to information disclosure, potentially exposing sensitive data.	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 2026-09-16 10:58:27 UTC

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

f2fs: limit recovery filename logging to stored length

F2FS stores recovery filenames as a length plus a fixed-size i_name
buffer.  The buffer is not NUL-terminated, but recover_inode() and
recover_dentry() print it with %s.

For a 255-byte filename, recovery logging can read past i_name into the
following raw inode fields.

Print the name with a precision bounded by i_namelen and F2FS_NAME_LEN.

Comment 1 Mauro Matteo Cascella 2026-09-21 18:38:32 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89838.mbox