Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved: xsk: validate MTU against usable frame size on bind AF_XDP bind currently accepts zero-copy pool configurations without verifying that the device MTU fits into the usable frame space provided by the UMEM chunk. This becomes a problem since we started to respect tailroom which is subtracted from chunk_size (among with headroom). 2k chunk size might not provide enough space for standard 1500 MTU, so let us catch such settings at bind time. Furthermore, validate whether underlying HW will be able to satisfy configured MTU wrt XSK’s frame size multiplied by supported Rx buffer chain length (that is exposed via net_device::xdp_zc_max_segs). A flaw was found in the Linux kernel’s AF_XDP (eXpress Data Path) subsystem. The AF_XDP bind operation fails to validate the Maximum Transmission Unit (MTU) against the usable frame space provided by the UMEM (User Memory) chunk. This can lead to situations where the configured MTU does not fit, potentially causing network communication failures or system instability. A local attacker could potentially leverage this vulnerability to disrupt network services, resulting in a denial of service.Details
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 13 | Planned | — |
| Ubuntu 24.04 | Planned | — |