CVEvulnerability
CVE-2026-90409
- Status
- Received
- Published
- 2026-09-17
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
drm/panthor: Add vm_bind region with kbo range overlap check
When a VM is created, caller has to specify the range of the address space
carve-out set aside for mapping kernel BO's. That means vm_bind mappings of
UM-exposed BO's should not intersect with that region, but at the moment
we're not checking this.
At first, I thought of giving these values to drm_gpuvm_init() through its
reserve_{offset, range} arguments, but it turns out that is meant for VM
address spans that are not managed through the usual drm_gpuvm split/merge
circuit, so storing the end of the user VA range at VM creation time and
doing a quick check in the vm_bind ioctl path was the simplest workaround.
The new check also makes sure vm_bind range doesn't overflow the size of a
64-bit unsigned integer. That was already being done further down the call
stack inside drm_gpuvm_sm_map -> drm_gpuvm_range_valid, but it's best to
fail early in the driver before GPUVM functions are invoked so that we
won't waste time allocating vm_bind context resources.
References
- https://git.kernel.org/stable/c/276753aaad65e6f7dac7989a600c1c2d3a382c1a git.kernel.org
- https://git.kernel.org/stable/c/761cf9c63274a5b711c3dc829601723215710d2d git.kernel.org
- https://git.kernel.org/stable/c/985f5e12f3cdf43030e13c2bbd154913133b5c3f git.kernel.org
- https://git.kernel.org/stable/c/f2be47fa8e225968eb66863657143fe900ec4bca git.kernel.org