Threats Tagged 'cve-2026-53067'

A high-severity use-after-free vulnerability in the Linux kernel's PCI endpoint MSI allocation code was resolved. The issue occurs when pci_epf_alloc_doorbell() allocates a doorbell message array and stores it before requesting MSI vectors. If MSI allocation fails, the array is freed but pointers remain, risking double-free or use-after-free. The fix clears these pointers on failure and returns an error if doorbells are already allocated to prevent overwriting or leaking allocations.

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-ep-msi: Fix error unwind and prevent double alloc pci_epf_alloc_doorbell() stores the allocated doorbell message array in epf->db_msg/epf->num_db before requesting MSI vectors. If MSI allocation fails, the array is freed but the EPF state may still point to freed memory. Clear epf->db_msg and epf->num_db on the MSI allocation failure path so that later cleanup cannot double-free the array and callers can retry allocation. Also return -EBUSY when doorbells have already been allocated to prevent leaking or overwriting an existing allocation.