In the Linux kernel, the following vulnerability has been resolved: idpf: avoid vport access in idpf_get_link_ksettings When the device control plane is removed or the platform running device control plane is rebooted, a reset is detected on the driver. On driver reset, it releases the resources and waits for the reset to complete. If the reset fails, it takes the error path and releases the vport lock. At this time if the monitoring tools tries to access link settings, it call traces for accessing released vport pointer. To avoid it, move link_speed_mbps to netdev_priv structure which removes the dependency on vport pointer and the vport lock in idpf_get_link_ksettings. Also use netif_carrier_ok() to check the link status and adjust the offsetof to use link_up instead of link_speed_mbps.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.