CVE-2026-80571 powerpc/pseries: papr-phy-attest - validate cmd.length, plug mem leak

In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries: papr-phy-attest - validate cmd.length, plug mem leak In paprphyattestcreatehandle, the params-cmd.length is not validated before use, which can result in a buffer overlow. Check it and return -EINVAL if it is...