1 // Check that if LSan finds that SP doesn't point into thread stack (e.g. 2 // if swapcontext is used), LSan will not hit the guard page. 3 // RUN: %clang_lsan %s -o %t && %run %t 4 #include <errno.h> 5 #include <stdio.h> 6 #include <stdlib.h> 7 #include <string.h> 8 #include <pthread.h> 9 #include <ucontext.h> 10 11 pthread_cond_t cond = PTHREAD_COND_INITIALIZER; 12 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; 13 int ctxfunc_started = 0; 14 15 static void die(const char* msg, int err) { 16 if (err == 0) 17 err = errno; 18 fprintf(stderr, "%s: %s\n", msg, strerror(err)); 19 exit(EXIT_FAILURE); 20 } 21 22 static void ctxfunc() { 23 pthread_mutex_lock(&mutex); 24 ctxfunc_started = 1; 25 pthread_cond_signal(&cond); 26 pthread_mutex_unlock(&mutex); 27 // Leave this context alive when the program exits. 28 for (;;); 29 } 30 31 static void* thread(void* arg) { 32 (void)arg; 33 ucontext_t ctx; 34 void* stack; 35 36 if (getcontext(&ctx) < 0) 37 die("getcontext", 0); 38 stack = malloc(1 << 10); 39 if (stack == NULL) 40 die("malloc", 0); 41 ctx.uc_stack.ss_sp = stack; 42 ctx.uc_stack.ss_size = 1 << 10; 43 makecontext(&ctx, ctxfunc, 0); 44 setcontext(&ctx); 45 die("setcontext", 0); 46 return NULL; 47 } 48 49 int main() { 50 pthread_t tid; 51 int i; 52 53 pthread_mutex_lock(&mutex); 54 i = pthread_create(&tid, NULL, thread, NULL); 55 if (i != 0) 56 die("pthread_create", i); 57 while (!ctxfunc_started) pthread_cond_wait(&cond, &mutex); 58 pthread_mutex_unlock(&mutex); 59 return 0; 60 } 61
