CVE-2025-38470CVE-2025-38470

In the Linux kernel, the following vulnerability has been resolved: net: vlan: fix VLAN 0 refcount imbalance of toggling filtering during runtime Assuming the "rx-vlan-filter" feature is enabled on a net device, the 8021q module will automatically add or remove VLAN 0 when the net device is put administratively up or down, respectively. There are a couple of problems with the above scheme. The first problem is a memory leak that can happen if the "rx-vlan-filter" feature is disabled while the device is running: # ip link add bond1 up type bond mode 0 # ethtool -K bond1 rx-vlan-filter off # ip link del dev bond1 When the device is put administratively down the "rx-vlan-filter" feature is disabled, so the 8021q module will not remove VLAN 0 and the memory will be leaked [1]. Another problem that can happen is that the kernel can automatically delete VLAN 0 when the device is put administratively down despite not adding it when the device was put administratively up since during