Bug 2559629 (CVE-2026-98961)

Summary:	CVE-2026-98961 kernel: btrfs: unlock inode and extent in caller when io_uring read extent fails
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 Btrfs file system. A local attacker can cause a Denial of Service (DoS) by triggering error conditions during asynchronous read operations. When an io_uring read request fails, such as during a memory allocation failure, the kernel does not release acquired internal file locks. This failure results in a deadlock that freezes file system operations and leaves the system unresponsive.	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 2026-10-23 12:45:21 UTC

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

btrfs: unlock inode and extent in caller when io_uring read extent fails

btrfs_uring_read_extent() runs only after btrfs_encoded_read() has taken
the inode shared lock and the extent lock.  On failure it used to unlock
in out_fail, and a pages-array allocation failure returned -ENOMEM
without unlocking at all.

Unlock in the caller instead on all failure returns, matching the
copy_to_user() error path.  The deferred -EIOCBQUEUED path still unlocks
in btrfs_uring_read_finished().