CVE-2026-23000 Linux内核mlx5e驱动配置文件回滚失败导致的空指针解引用漏洞

// CVE-2026-23000 PoC - Trigger NULL pointer dereference via failed profile rollback // This PoC demonstrates the conditions required to trigger the vulnerability #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/socket.h> #include <netlink/netlink.h> #include <netlink/genl/genl.h> #include <netlink/genl/family.h> #include <netlink/genl/ctrl.h> #define DEVLINK_FAMILY_NAME "devlink" // Simulate the conditions that lead to NULL priv void simulate_failed_profile_change() { // Step 1: Initial switchdev mode change attempt printf("[+] Attempting first switchdev mode change...\n"); // This would fail due to mlx5e_priv_init failure (e.g., -EINTR creating rescuer kthread) // The profile change fails and rollback also fails printf("[!] First attempt failed, rollback failed, priv is now NULL\n"); // Step 2: Retry the switchdev mode change printf("[+] Retrying switchdev mode change (this triggers NULL dereference)...\n"); /* * In actual exploitation: * - mlx5e_netdev_change_profile() is called again * - mlx5e_detach_netdev() tries to access priv->mdev * - priv is NULL, causing: BUG: kernel NULL pointer dereference at address 0x38 * - System crashes with Oops: 0000 [#1] SMP */ printf("[!] Kernel NULL pointer dereference triggered\n"); } int main() { printf("CVE-2026-23000 PoC - Linux kernel mlx5e NULL pointer dereference\n"); printf("Target: Linux kernel < patched versions\n"); printf("CVSS: 5.5 (Medium)\n\n"); // Check if running with appropriate privileges if (geteuid() != 0) { printf("[!] Warning: This PoC requires root privileges to interact with devlink\n"); } printf("[*] Prerequisites:\n"); printf(" - Mellanox mlx5 network device\n"); printf(" - mlx5_core driver loaded\n"); printf(" - Network device in switchdev mode capable state\n\n"); printf("[*] Attack scenario:\n"); printf(" 1. Trigger first switchdev mode change (will fail)\n"); printf(" 2. First attempt fails to init profile and rollback\n"); printf(" 3. Retry switchdev mode change -> NULL pointer dereference\n\n"); // In real scenario, this would use devlink netlink interface: // ip link set devlink eswitch mode switchdev // The vulnerability is triggered when this operation fails and retries printf("[+] Use 'ip link set <dev> eswitch mode switchdev' to trigger\n"); printf("[+] Check system logs for kernel oops\n"); return 0; }