CVE-2026-43239 Linux内核SMB客户端竞态条件漏洞

/* * PoC Concept: Race Condition in SMB Client Interface Update * This code simulates the vulnerable logic where two threads * update the shared interface state without proper locking. */ #include <stdio.h> #include <pthread.h> #include <unistd.h> // Simulating the vulnerable kernel structure struct iface_info { long long last_update; int data; }; struct iface_info global_iface = {0, 0}; // Simulate the vulnerable ->query_interfaces() work function void* malicious_query_work(void* arg) { printf("[Thread %ld] Starting query work...\n", (long)arg); // Vulnerable check: Read last_update without lock long long current_time = time(NULL); if (global_iface.last_update < current_time) { // Simulate processing delay to widen the race window usleep(1000); // Vulnerable update: Write to shared resource without lock // Two threads may do this simultaneously based on the same check global_iface.last_update = current_time; global_iface.data++; printf("[Thread %ld] Updated interface data to: %d\n", (long)arg, global_iface.data); } return NULL; } int main() { pthread_t t1, t2; printf("Starting PoC to trigger race condition...\n"); // Create two threads to simulate concurrent query works pthread_create(&t1, NULL, malicious_query_work, (void*)1); pthread_create(&t2, NULL, malicious_query_work, (void*)2); pthread_join(t1, NULL); pthread_join(t2, NULL); printf("Final interface data: %d (Inconsistent state possible)\n", global_iface.data); return 0; }