test/asan/TestCases/Linux/uar_signals.cc

   1 // This test shows that the current implementation of use-after-return is
   2 // not signal-safe.
   3 // RUN: %clangxx_asan -O1 %s -o %t -lpthread && %t
   4 // RUN: %clangxx_asan -O1 %s -o %t -lpthread && %t
   5 #include <signal.h>
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <sys/time.h>
   9 #include <pthread.h>
  10
  11 int *g;
  12 int n_signals;
  13
  14 typedef void (*Sigaction)(int, siginfo_t *, void *);
  15
  16 void SignalHandler(int, siginfo_t*, void*) {
  17   int local;
  18   g = &local;
  19   n_signals++;
  20   // printf("s: %p\n", &local);
  21 }
  22
  23 static void EnableSigprof(Sigaction SignalHandler) {
  24   struct sigaction sa;
  25   sa.sa_sigaction = SignalHandler;
  26   sa.sa_flags = SA_RESTART | SA_SIGINFO;
  27   sigemptyset(&sa.sa_mask);
  28   if (sigaction(SIGPROF, &sa, NULL) != 0) {
  29     perror("sigaction");
  30     abort();
  31   }
  32   struct itimerval timer;
  33   timer.it_interval.tv_sec = 0;
  34   timer.it_interval.tv_usec = 1;
  35   timer.it_value = timer.it_interval;
  36   if (setitimer(ITIMER_PROF, &timer, 0) != 0) {
  37     perror("setitimer");
  38     abort();
  39   }
  40 }
  41
  42 void RecursiveFunction(int depth) {
  43   if (depth == 0) return;
  44   int local;
  45   g = &local;
  46   // printf("r: %p\n", &local);
  47   // printf("[%2d] n_signals: %d\n", depth, n_signals);
  48   RecursiveFunction(depth - 1);
  49   RecursiveFunction(depth - 1);
  50 }
  51
  52 void *Thread(void *) {
  53   RecursiveFunction(18);
  54   return NULL;
  55 }
  56
  57 int main(int argc, char **argv) {
  58   EnableSigprof(SignalHandler);
  59
  60   for (int i = 0; i < 4; i++) {
  61     fprintf(stderr, ".");
  62     const int kNumThread = sizeof(void*) == 8 ? 16 : 8;
  63     pthread_t t[kNumThread];
  64     for (int i = 0; i < kNumThread; i++)
  65       pthread_create(&t[i], 0, Thread, 0);
  66     for (int i = 0; i < kNumThread; i++)
  67       pthread_join(t[i], 0);
  68   }
  69   fprintf(stderr, "\n");
  70 }