Description
In the Linux kernel, the following vulnerability has been resolved:
drm/imagination: Fix reference and vm_bo handling in remap()
When a map overlaps part of an existing mapping, pvr_vm_gpuva_remap()
splits the mapping into prev/next parts covering what the request did
not take, instead of creating something new. It gets two things wrong.
- A GEM reference is taken for each part but it's never needed and never
dropped, so it leaks one reference per split (remap-next-in-2m in
tests/imagination/pvr_vm_map.c):
CRITICAL: 33558528 bytes of shmem still held after close
- The parts still belong to the original object being split, but
pvr_vm_gpuva_remap() links them to ctx->gpuvm_bo, the new object's
vm_bo:
prev_va --obj--> BO_A BO_B <--obj-- vm_bo (ctx->gpuvm_bo)
\___________link___________/ (mismatch: BO_A != BO_B)
drm_gpuva_link() catches the mismatch:
WARNING: drivers/gpu/drm/drm_gpuvm.c:2108 at drm_gpuva_link+0x2ec/0x310
drm_WARN_ON(obj != vm_bo->obj)
Call trace:
drm_gpuva_link
pvr_vm_gpuva_remap
__drm_gpuvm_sm_map
pvr_vm_map
pvr_ioctl_vm_map
Link them to op->remap.unmap->va->vm_bo instead.
The locking of the GPUVA lists of the other objects touched by a split is
not addressed here; it is handled by switching the GPUVM to immediate
mode.
drm/imagination: Fix reference and vm_bo handling in remap()
When a map overlaps part of an existing mapping, pvr_vm_gpuva_remap()
splits the mapping into prev/next parts covering what the request did
not take, instead of creating something new. It gets two things wrong.
- A GEM reference is taken for each part but it's never needed and never
dropped, so it leaks one reference per split (remap-next-in-2m in
tests/imagination/pvr_vm_map.c):
CRITICAL: 33558528 bytes of shmem still held after close
- The parts still belong to the original object being split, but
pvr_vm_gpuva_remap() links them to ctx->gpuvm_bo, the new object's
vm_bo:
prev_va --obj--> BO_A BO_B <--obj-- vm_bo (ctx->gpuvm_bo)
\___________link___________/ (mismatch: BO_A != BO_B)
drm_gpuva_link() catches the mismatch:
WARNING: drivers/gpu/drm/drm_gpuvm.c:2108 at drm_gpuva_link+0x2ec/0x310
drm_WARN_ON(obj != vm_bo->obj)
Call trace:
drm_gpuva_link
pvr_vm_gpuva_remap
__drm_gpuvm_sm_map
pvr_vm_map
pvr_ioctl_vm_map
Link them to op->remap.unmap->va->vm_bo instead.
The locking of the GPUVA lists of the other objects touched by a split is
not addressed here; it is handled by switching the GPUVM to immediate
mode.
Published:
2026-10-23
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
Advisories
No advisories yet.
References
History
Fri, 23 Oct 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: drm/imagination: Fix reference and vm_bo handling in remap() When a map overlaps part of an existing mapping, pvr_vm_gpuva_remap() splits the mapping into prev/next parts covering what the request did not take, instead of creating something new. It gets two things wrong. - A GEM reference is taken for each part but it's never needed and never dropped, so it leaks one reference per split (remap-next-in-2m in tests/imagination/pvr_vm_map.c): CRITICAL: 33558528 bytes of shmem still held after close - The parts still belong to the original object being split, but pvr_vm_gpuva_remap() links them to ctx->gpuvm_bo, the new object's vm_bo: prev_va --obj--> BO_A BO_B <--obj-- vm_bo (ctx->gpuvm_bo) \___________link___________/ (mismatch: BO_A != BO_B) drm_gpuva_link() catches the mismatch: WARNING: drivers/gpu/drm/drm_gpuvm.c:2108 at drm_gpuva_link+0x2ec/0x310 drm_WARN_ON(obj != vm_bo->obj) Call trace: drm_gpuva_link pvr_vm_gpuva_remap __drm_gpuvm_sm_map pvr_vm_map pvr_ioctl_vm_map Link them to op->remap.unmap->va->vm_bo instead. The locking of the GPUVA lists of the other objects touched by a split is not addressed here; it is handled by switching the GPUVM to immediate mode. | |
| Title | drm/imagination: Fix reference and vm_bo handling in remap() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-23T12:19:08.946Z
Reserved: 2026-09-25T10:25:14.382Z
Link: CVE-2026-98949
No data.
Status : Received
Published: 2026-10-23T13:17:16.037
Modified: 2026-10-23T13:17:16.037
Link: CVE-2026-98949
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.