Bug 2425125 (CVE-2023-54089)

Summary:	CVE-2023-54089 kernel: virtio_pmem: add the missing REQ_OP_WRITE for flush bio
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	Keywords:	Security
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was discovered in the virtio_pmem driver in the Linux kernel, where flush block I/O requests did not have the required REQ_OP_WRITE operation code assigned before submission. Under workloads involving persistent memory block devices — for example, running mkfs.xfs on a pmem device,this omission can lead to bio submission warnings and improper block I/O handling.	Story Points:	---
Clone Of:		Environment:
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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 2025-12-24 14:04:46 UTC

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

virtio_pmem: add the missing REQ_OP_WRITE for flush bio

When doing mkfs.xfs on a pmem device, the following warning was

 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 384 at block/blk-core.c:751 submit_bio_noacct
 Modules linked in:
 CPU: 2 PID: 384 Comm: mkfs.xfs Not tainted 6.4.0-rc7+ #154
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
 RIP: 0010:submit_bio_noacct+0x340/0x520
 ......
 Call Trace:
  <TASK>
  ? submit_bio_noacct+0xd5/0x520
  submit_bio+0x37/0x60
  async_pmem_flush+0x79/0xa0
  nvdimm_flush+0x17/0x40
  pmem_submit_bio+0x370/0x390
  __submit_bio+0xbc/0x190
  submit_bio_noacct_nocheck+0x14d/0x370
  submit_bio_noacct+0x1ef/0x520
  submit_bio+0x55/0x60
  submit_bio_wait+0x5a/0xc0
  blkdev_issue_flush+0x44/0x60

The root cause is that submit_bio_noacct() needs bio_op() is either
WRITE or ZONE_APPEND for flush bio and async_pmem_flush() doesn't assign
REQ_OP_WRITE when allocating flush bio, so submit_bio_noacct just fail
the flush bio.

Simply fix it by adding the missing REQ_OP_WRITE for flush bio. And we
could fix the flush order issue and do flush optimization later.

Comment 1 Alexander B 2025-12-25 00:37:48 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025122406-CVE-2023-54089-ddc6@gregkh/T