Bug 2546432 (CVE-2026-98352)

Summary:	CVE-2026-98352 kernel: RDMA/rtrs-clt: Fix CQ pool leak when connect is interrupted
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 Remote Direct Memory Access (RDMA) Transport client driver. A race condition occurs when a connection setup attempt is interrupted during teardown, causing shared Completion Queue (CQ) resources to be retained without being released. This flaw may allow an attacker to cause a resource leak, potentially resulting in a Denial of Service (DoS) or kernel instability during device cleanup.	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 2026-10-06 09:20:02 UTC

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

RDMA/rtrs-clt: Fix CQ pool leak when connect is interrupted

The client borrows shared CQ credits in the ADDR_RESOLVED handler via
ib_cq_pool_get(), before the peer is connected. create_cm() can return
-ERESTARTSYS from wait_event_interruptible_timeout() without destroying
the CM ID. The init_conns() and stop-and-destroy paths then call
destroy_con_cq_qp() while cq is still NULL (no PUT) and only afterwards
rdma_destroy_id().

CMA serializes the handler against rdma_destroy_id() with handler_mutex,
but that does not order the GET against destroy_con_cq_qp(). If
ADDR_RESOLVED has already passed the DESTROYING check, it can take
con_mutex, GET credits, and then lose the con to kfree. Device
unregister later hits WARN_ON(cq->cqe_used) in ib_cq_pool_cleanup().

Set a per-connection flag under con_mutex before CQ/QP teardown so a
racing ADDR_RESOLVED cannot borrow credits after teardown has begun.

Comment 1 gkamathe 2026-10-10 14:48:31 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98352.mbox