CVE-2026-90120

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

irqchip/gic-v5: Check get_logical_index() return value in MADT IAFFID parsing

In gic_acpi_parse_iaffid() a given MADT GICC entry might not correspond
to a logical cpu recognized by the kernel, resulting in the cpu variable
initialization to an error value.

Currently, the get_logical_index() return value is not checked for failure,
which might result in out-of-bounds memory corruption while trying to
index a per_cpu variable array.

Add a check to evaluate get_logical_index() return value.