In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid

In the Linux kernel, the following vulnerability has been resolved:

KVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits

Userspace can restore an ITS Device Table Entry whose Size field encodes
more EventID bits than the virtual ITS supports. The live MAPD path
rejects that state, but vgic_its_restore_dte() accepts it and stores the
out-of-range value in dev->num_eventid_bits.

Reject restored DTEs with num_eventid_bits > VITS_TYPER_IDBITS before
allocating the device. This mirrors the MAPD check and prevents the
restored state from reaching vgic_its_restore_itt(), where the unchecked
value can be converted into an oversized scan_its_table() range.