CVE-2026-43094

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

ixgbevf: add missing negotiate_features op to Hyper-V ops table

Commit a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by

negotiating supported features") added the .negotiate_features callback

to ixgbe_mac_operations and populated it in ixgbevf_mac_ops, but forgot

to add it to ixgbevf_hv_mac_ops. This leaves the function pointer NULL

on Hyper-V VMs.

During probe, ixgbevf_negotiate_api() calls ixgbevf_set_features(),

which unconditionally dereferences hw->mac.ops.negotiate_features().

On Hyper-V this results in a NULL pointer dereference:

BUG: kernel NULL pointer dereference, address: 0000000000000000

[...]

Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine [...]

Workqueue: events work_for_cpu_fn

RIP: 0010:0x0

[...]

Call Trace:

ixgbevf_negotiate_api+0x66/0x160 [ixgbevf]

ixgbevf_sw_init+0xe4/0x1f0 [ixgbevf]

ixgbevf_probe+0x20f/0x4a0 [ixgbevf]

local_pci_probe+0x50/0xa0

work_for_cpu_fn+0x1a/0x30

[...]

Add ixgbevf_hv_negotiate_features_vf() that returns -EOPNOTSUPP and

wire it into ixgbevf_hv_mac_ops. The caller already handles -EOPNOTSUPP

gracefully.