CVE-2026-68103
HighCVSS 7.1Exploitation Probability (EPSS)
Low risk1th percentile - higher than 1% of all known CVEs
Summary
In the Linux kernel, the amdgpu driver fixed an issue with doorbell mapping. Previously, xa_store_irq() allowed a newly created queue to overwrite an existing doorbell mapping, potentially causing misrouting of fence IRQ processing or erasing another queue's mapping. The fix uses xa_insert_irq(), which rejects mapping a reserved doorbell to a new queue.
Risk Assessment
Incorrect doorbell mapping may lead to GPU malfunction, potentially enabling data integrity attacks or system crashes.
Recommendation
Apply the Linux kernel update containing this commit to prevent doorbell mapping overwrites.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: reject mapping a reserved doorbell to a new queue When creating an user-queue, the user space provides a doorbell BO handle and an offset within the bo to obtain a doorbell. However current implementation using xa_store_irq() to store a doorbell, which allows a later queue created with the same BO and offset parameters to overwrite an existing queue and doorbell mapping. This can cause problems like misrouting fence IRQ processing to a wrong queue, and mislead the cleanup process of one queue erasing the mapping of another queue. This commit fixes this issue by replacing xa_store_irq with xa_insert_irq, which rejects mapping a reserved doorbell to a newly created queue (cherry picked from commit 6244eae22966350db52faf9c1369d3b2ffc5de4e)