CVE-2025-37945 — net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY

Affected: Linux, 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: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY

DSA has 2 kinds of drivers:

1. Those who call dsa_switch_suspend() and dsa_switch_resume() from their device PM ops: qca8k-8xxx, bcm_sf2, microchip ksz 2. Those who don't: all others. The above methods should be optional.

For type 1, dsa_switch_suspend() calls dsa_user_suspend() -> phylink_stop(), and dsa_switch_resume() calls dsa_user_resume() -> phylink_start(). These seem good candidates for setting mac_managed_pm = true because that is essentially its definition [1], but that does not seem to be the biggest problem for now, and is not what this change focuses on.

Talking strictly about the 2nd category of DSA drivers here (which do not have MAC managed PM, meaning that for their attached PHYs, mdio_bus_phy_suspend() and mdio_bus_phy_resume() should run in full), I have noticed that the following warning from mdio_bus_phy_resume() is triggered:

WARN_ON(phydev->state != PHY_HALTED && phydev->state != PHY_READY && phydev->state != PHY_UP);

because the PHY state machine is running.

It's running as a result of a previous dsa_user_open() -> ... -> phylink_start() -> phy_start() having been initiated by the user.

The previous mdio_bus_phy_suspend() was supposed to have called phy_stop_machine(), but it didn't. So this is why the PHY is in state PHY_NOLINK by the time mdio_bus_phy_resume() runs.

mdio_bus_phy_su…

USN-7594-1 — linux, linux-gcp, linux-raspi, linux-realtime vulnerabilities

Affected: Ubuntu:25.04: linux, Ubuntu:25.04: linux-gcp, Ubuntu:25.04: linux-raspi, Ubuntu:25.04: linux-realtime

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM32 architecture; - ARM64 architecture; - PowerPC architecture; - RISC-V architecture; - User-Mode Linux (UML); - x86 architecture; - Block layer subsystem; - Cryptographic API; - Compute Acceleration Framework; - ACPI drivers; - Serial ATA and Parallel ATA drivers; - Drivers core; - Ublk userspace block driver; - Bluetooth drivers; - Bus devices; - TPM device driver; - Clock framework and drivers; - CPU frequency scaling framework; - Buffer Sharing and Synchronization framework; - DMA engine subsystem; - GPU drivers; - HID subsystem; - HSI subsystem; - I2C subsystem; - I3C subsystem; - IIO subsystem; - InfiniBand drivers; - IOMMU subsystem; - IRQ chip drivers; - MCB driver; - Multiple devices driver; - Media drivers; - MemoryStick subsystem; - Multifunction device drivers; - Microchip PCI driver; - Intel Management Engine Interface driver; - PCI Endpoint Test driver; - MTD block device drivers; - Network drivers; - Ethernet bonding driver; - Mellanox network drivers; - STMicroelectronics network drivers; - NTB driver; - NVME drivers; - PCI subsystem; - Synopsys DesignWare PCIe PMU; - Mellanox platform drivers; - PWM drivers; - Remote Processor subsystem; - S/390 drivers; - SCSI subsystem; -…

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CVE-2025-37945 — net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY

USN-7594-1 — linux, linux-gcp, linux-raspi, linux-realtime vulnerabilities