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
die(const char * msg,int err)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
ctxfunc()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
thread(void * arg)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
main()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