Bug 2482166 (CVE-2026-45852)

Summary:	CVE-2026-45852 kernel: RDMA/rxe: Fix double free in rxe_srq_from_init
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
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 Linux kernel's Remote Direct Memory Access (RDMA) subsystem, specifically within the `rxe` driver. An error in the `rxe_srq_from_init` function's memory management can lead to a double free vulnerability. This occurs when an attempt to copy data to user space fails, causing the same memory region to be freed twice. A local attacker could potentially exploit this flaw to cause a denial of service (DoS) by crashing the system.	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 2026-05-27 15:14:26 UTC

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

RDMA/rxe: Fix double free in rxe_srq_from_init

In rxe_srq_from_init(), the queue pointer 'q' is assigned to
'srq->rq.queue' before copying the SRQ number to user space.
If copy_to_user() fails, the function calls rxe_queue_cleanup()
to free the queue, but leaves the now-invalid pointer in
'srq->rq.queue'.

The caller of rxe_srq_from_init() (rxe_create_srq) eventually
calls rxe_srq_cleanup() upon receiving the error, which triggers
a second rxe_queue_cleanup() on the same memory, leading to a
double free.

The call trace looks like this:
   kmem_cache_free+0x.../0x...
   rxe_queue_cleanup+0x1a/0x30 [rdma_rxe]
   rxe_srq_cleanup+0x42/0x60 [rdma_rxe]
   rxe_elem_release+0x31/0x70 [rdma_rxe]
   rxe_create_srq+0x12b/0x1a0 [rdma_rxe]
   ib_create_srq_user+0x9a/0x150 [ib_core]

Fix this by moving 'srq->rq.queue = q' after copy_to_user.

Comment 1 Keith Grant 2026-05-28 04:45:26 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052708-CVE-2026-45852-fcf9@gregkh/T

Comment 4 errata-xmlrpc 2026-06-10 20:00:21 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:25120 https://access.redhat.com/errata/RHSA-2026:25120

Comment 5 errata-xmlrpc 2026-06-10 21:39:07 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:25121 https://access.redhat.com/errata/RHSA-2026:25121

Comment 6 errata-xmlrpc 2026-06-11 10:13:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:25217 https://access.redhat.com/errata/RHSA-2026:25217

Comment 7 errata-xmlrpc 2026-06-22 05:01:25 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:27713 https://access.redhat.com/errata/RHSA-2026:27713

Comment 8 errata-xmlrpc 2026-07-01 00:15:55 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Via RHSA-2026:33899 https://access.redhat.com/errata/RHSA-2026:33899

Comment 9 errata-xmlrpc 2026-07-01 08:59:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:34094 https://access.redhat.com/errata/RHSA-2026:34094

Comment 10 errata-xmlrpc 2026-07-06 04:20:46 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:35844 https://access.redhat.com/errata/RHSA-2026:35844

Comment 11 errata-xmlrpc 2026-07-06 04:51:33 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:35863 https://access.redhat.com/errata/RHSA-2026:35863

Comment 12 errata-xmlrpc 2026-07-06 14:26:47 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Via RHSA-2026:35896 https://access.redhat.com/errata/RHSA-2026:35896

Comment 13 errata-xmlrpc 2026-07-17 12:52:37 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:41236 https://access.redhat.com/errata/RHSA-2026:41236