CVE-2026-80993

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

net: phylink: correctly validate returned PCS in phylink inband caps

In phylink inband caps(), the PCS returned by mac select pcs is only checked if NULL but mac select pcs can also return an error pointer.

This can cause a kernel panic as phylink pcs inband caps() only checks if passed PCS is not NULL and directly dereference ops from the phylink pcs struct.

Use the IS ERR OR NULL macro to address both case where the returned PCS can be NULL or an error pointer and prevent a kernel panic.