1 // Test interaction of Asan recovery mode with asynch signals.
2 //
3 // RUN: %clang_asan -fsanitize-recover=address -pthread %s -o %t
4 //
5 // RUN: %env_asan_opts=halt_on_error=false:suppress_equal_pcs=false %run %t 100 >%t.log 2>&1 || true
6 // Collision will almost always get triggered but we still need to check the unlikely case:
7 // RUN: FileCheck --check-prefix=CHECK-COLLISION %s <%t.log || FileCheck --check-prefix=CHECK-NO-COLLISION %s <%t.log
8 
9 #define _SVID_SOURCE 1  // SA_NODEFER
10 
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <pthread.h>
15 #include <time.h>
16 #include <signal.h>
17 
18 #include <sanitizer/asan_interface.h>
19 
random_delay(unsigned * seed)20 void random_delay(unsigned *seed) {
21   *seed = 1664525 * *seed + 1013904223;
22   struct timespec delay = { 0, (*seed % 1000) * 1000 };
23   nanosleep(&delay, 0);
24 }
25 
26 volatile char bad[2] = {1, };
27 
error()28 void error() {
29   // CHECK-COLLISION: AddressSanitizer: nested bug in the same thread, aborting
30   // CHECK-NO-COLLISION: AddressSanitizer: use-after-poison
31   volatile int idx = 0;
32   bad[idx] = 0;
33 }
34 
35 #define CHECK_CALL(e, msg) do {             \
36   if (0 != (e)) {                           \
37     fprintf(stderr, "Failed to " msg "\n"); \
38     exit(1);                                \
39   }                                         \
40 } while (0)
41 
42 size_t niter = 10;
43 pthread_t sender_tid, receiver_tid;
44 
45 pthread_mutex_t keep_alive_mu = PTHREAD_MUTEX_INITIALIZER;
46 
sender(void * arg)47 void *sender(void *arg) {
48   unsigned seed = 0;
49   for (size_t i = 0; i < niter; ++i) {
50     random_delay(&seed);
51     CHECK_CALL(pthread_kill(receiver_tid, SIGUSR1), "send signal");
52   }
53   return 0;
54 }
55 
handler(int sig)56 void handler(int sig) {
57   // Expect error collisions here
58   error();
59 }
60 
receiver(void * arg)61 void *receiver(void *arg) {
62   unsigned seed = 1;
63   for (size_t i = 0; i < niter; ++i) {
64     random_delay(&seed);
65     // And here
66     error();
67   }
68   // Parent will release this when it's ok to terminate
69   CHECK_CALL(pthread_mutex_lock(&keep_alive_mu), "unlock mutex");
70   return 0;
71 }
72 
main(int argc,char ** argv)73 int main(int argc, char **argv) {
74   if (argc != 2) {
75     fprintf(stderr, "Syntax: %s niter\n", argv[0]);
76     exit(1);
77   }
78 
79   niter = (size_t)strtoul(argv[1], 0, 0);
80 
81   struct sigaction sa;
82   memset(&sa, 0, sizeof(sa));
83   sa.sa_handler = handler;
84   sa.sa_flags = SA_NODEFER; // Enable nested handlers to add more stress
85   CHECK_CALL(sigaction(SIGUSR1, &sa, 0), "set sighandler");
86 
87   __asan_poison_memory_region(&bad, sizeof(bad));
88 
89   CHECK_CALL(pthread_mutex_lock(&keep_alive_mu), "lock mutex");
90   CHECK_CALL(pthread_create(&receiver_tid, 0, receiver, 0), "start thread");
91   CHECK_CALL(pthread_create(&sender_tid, 0, sender, 0), "start thread");
92   CHECK_CALL(pthread_join(sender_tid, 0), "join thread");
93   // Now allow receiver to die
94   CHECK_CALL(pthread_mutex_unlock(&keep_alive_mu), "unlock mutex");
95   CHECK_CALL(pthread_join(receiver_tid, 0), "join thread");
96 
97   // CHECK-NO-COLLISION: All threads terminated
98   printf("All threads terminated\n");
99 
100   return 0;
101 }
102