Bug 2546471 (CVE-2026-98178)

Summary: CVE-2026-98178 kernel: drm/amdgpu: Skip KFD mapping clear before initialization
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: 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 AMD GPU driver. When compute subsystem initialization fails, uninitialized device structures remain attached to the graphics driver. A local user capable of triggering a GPU reset can cause the system to dereference an unallocated memory pointer, resulting in a kernel crash and 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 2026-10-06 09:26:04 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu: Skip KFD mapping clear before initialization

amdgpu_amdkfd_clear_kfd_mapping() assumes that a non-NULL kfd_dev
has a fully populated node array. This is not true when KFD device
initialization fails after probe.

For example, kgd2kfd_device_init() sets num_nodes before checking
PCIe atomics support. On Polaris systems without the required atomics,
it returns before allocating nodes[0], but the kfd_dev remains attached
to the amdgpu device. A later GPU reset then dereferences nodes[0]->id.

Require the authoritative KFD initialization flag before walking the
node array, matching the existing KFD reset and teardown paths.

(cherry picked from commit 4ac1835823c47903fbb278bbf474773c46f59edc)
Comment 1 Mauro Matteo Cascella 2026-10-08 11:47:18 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98178.mbox