CVE-2026-31431 (Copy Fail)

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

crypto: algif_aead - Revert to operating out-of-place

This mostly reverts commit 72548b093ee3 except for the copying of
the associated data.

There is no benefit in operating in-place in algif_aead since the
source and destination come from different mappings.  Get rid of
all the complexity added for in-place operation and just copy the
AD directly.