1 // Tests UAF detection where Allocate/Deallocate/Use
2 // happen in separate threads.
3 // RUN: %clang_hwasan %s -o %t && not %run %t 2>&1 | FileCheck %s
4 // REQUIRES: stable-runtime
5 
6 #include <pthread.h>
7 #include <stdlib.h>
8 #include <stdio.h>
9 
10 #include <sanitizer/hwasan_interface.h>
11 
12 char *volatile x;
13 int state;
14 
Allocate(void * arg)15 void *Allocate(void *arg) {
16   x = (char*)malloc(10);
17   __sync_fetch_and_add(&state, 1);
18   while (__sync_fetch_and_add(&state, 0) != 3) {}
19   return NULL;
20 }
Deallocate(void * arg)21 void *Deallocate(void *arg) {
22   free(x);
23   __sync_fetch_and_add(&state, 1);
24   while (__sync_fetch_and_add(&state, 0) != 3) {}
25   return NULL;
26 }
27 
Use(void * arg)28 void *Use(void *arg) {
29   x[5] = 42;
30   // CHECK: ERROR: HWAddressSanitizer: tag-mismatch on address
31   // CHECK: WRITE of size 1 {{.*}} in thread T3
32   // CHECK: thread-uaf.c:[[@LINE-3]]
33   // CHECK: freed by thread T2 here
34   // CHECK: in Deallocate
35   // CHECK: previously allocated here:
36   // CHECK: in Allocate
37   // CHECK: Thread: T2 0x
38   // CHECK: Thread: T3 0x
39   // CHECK-DAG: Thread: T0 0x
40   // CHECK-DAG: Thread: T1 0x
41   __sync_fetch_and_add(&state, 1);
42   return NULL;
43 }
44 
main()45 int main() {
46   __hwasan_enable_allocator_tagging();
47   pthread_t t1, t2, t3;
48 
49   pthread_create(&t1, NULL, Allocate, NULL);
50   while (__sync_fetch_and_add(&state, 0) != 1) {}
51   pthread_create(&t2, NULL, Deallocate, NULL);
52   while (__sync_fetch_and_add(&state, 0) != 2) {}
53   pthread_create(&t3, NULL, Use, NULL);
54 
55   pthread_join(t1, NULL);
56   pthread_join(t2, NULL);
57   pthread_join(t3, NULL);
58 }
59