Bug 2521417 (CVE-2026-74617)

Summary: CVE-2026-74617 kernel: dibs: initialise dibs->lock in dibs_dev_alloc()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: 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 dibs device driver. The `dibs->lock` was not properly initialized when a dibs device was allocated, allowing a Global ID (GID) event interrupt to occur before the lock was ready. This could lead to the system attempting to acquire an uninitialized lock, potentially causing a system crash and resulting in a Denial of Service (DoS).
 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 2026-08-22 15:44:34 UTC 
In the Linux kernel, the following vulnerability has been resolved:

dibs: initialise dibs->lock in dibs_dev_alloc()

dibs->lock is initialised by dibs_dev_add(), but a dibs device can
already take interrupts before that call: ism_probe() runs
ism_dev_init(), and hence request_irq(), before it calls
dibs_dev_add(). No client can have registered a dmb at that point, so
no dmb interrupt can occur, but a GID event interrupt can, and
ism_handle_irq() takes dibs->lock unconditionally on entry, before it
inspects anything else.

Initialise the lock in dibs_dev_alloc() instead, so that it is valid as
soon as a driver can publish the device to its interrupt handler.
Comment 1 Mauro Matteo Cascella 2026-08-24 13:07:05 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026082218-CVE-2026-74617-52a0@gregkh/T