CVE-2026-89673

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

nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo

nfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation as 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque() calls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes. The mismatch means the declared da_addr_body length exceeds the actual encoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply, leaking stale reply-page content to the client and mis-aligning the subsequent version list decode.

Use xdr_align_size() for each string length to match what xdr_encode_opaque() actually writes.