CVE-2026-31727

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

usb: gadget: uether: Fix NULL pointer deref in ethget_drvinfo

Commit ec35c1969650 ("usb: gadget: fncm: Fix netdevice lifecycle with device_move") reparents the gadget device to /sys/devices/virtual during unbind, clearing the gadget pointer. If the userspace tool queries on the surviving interface during this detached window, this leads to a NULL pointer dereference.

Unable to handle kernel NULL pointer dereference Call trace: ethgetdrvinfo+0x50/0x90 ethtoolgetdrvinfo+0x5c/0x1f0 _devethtool+0xaec/0x1fe0 devethtool+0x134/0x2e0 devioctl+0x338/0x560

Add a NULL check for dev->gadget in ethgetdrvinfo(). When detached, skip copying the fwversion and businfo strings, which is natively handled by ethtoolgetdrvinfo for empty strings.