CVE-2026-46321

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tun: free page on short-frame rejection in tun_xdp_one()<br /> <br /> tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without<br /> freeing the page that vhost_net_build_xdp() allocated for it.<br /> tun_sendmsg() discards that -EINVAL and still returns total_len, so<br /> vhost_tx_batch() takes the success path and never frees the page; each<br /> short frame in a batch leaks one page-frag chunk.<br /> <br /> A local process that can open /dev/net/tun and /dev/vhost-net can hit<br /> this path: it attaches a tun/tap device as the vhost-net backend and<br /> feeds TX descriptors whose length minus the virtio-net header is below<br /> ETH_HLEN. Each kick leaks the page-frag chunks for that batch, and a<br /> tight submission loop exhausts host memory and triggers an OOM panic.<br /> Free the page before returning -EINVAL, matching the XDP-program error<br /> path in the same function.