CVE-2026-63868 net: garp: fix unsigned integer underflow in garp_pdu_parse_attr

In the Linux kernel, the following vulnerability has been resolved: net: garp: fix unsigned integer underflow in garppduparseattr The receive-side GARP attribute parser computes dlen with reversed operands: dlen = sizeofga - ga-len; ga-len is the on-wire attribute length and includes the GARP...