Affected: Linux, Siemens SIMATIC CN 4100, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

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

net: usb: asix_devices: Fix PHY address mask in MDIO bus initialization

Syzbot reported shift-out-of-bounds exception on MDIO bus initialization.

The PHY address should be masked to 5 bits (0-31). Without this mask, invalid PHY addresses could be used, potentially causing issues with MDIO bus operations.

Fix this by masking the PHY address with 0x1f (31 decimal) to ensure it stays within the valid range.