1 // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t
2 //
3 // Test that va_arg shadow from a signal handler does not leak outside.
4 
5 // Reported deadly signal due to stack-overflow
6 // XFAIL: netbsd
7 
8 #include <signal.h>
9 #include <stdarg.h>
10 #include <sanitizer/msan_interface.h>
11 #include <assert.h>
12 #include <sys/time.h>
13 #include <stdio.h>
14 
15 const int kSigCnt = 200;
16 
17 void f(bool poisoned, int n, ...) {
18   va_list vl;
19   va_start(vl, n);
20   for (int i = 0; i < n; ++i) {
21     void *p = va_arg(vl, void *);
22     if (!poisoned)
23       assert(__msan_test_shadow(&p, sizeof(p)) == -1);
24   }
25   va_end(vl);
26 }
27 
28 int sigcnt;
29 
30 void SignalHandler(int signo) {
31   assert(signo == SIGPROF);
32   void *p;
33   void **volatile q = &p;
34   f(true, 10,
35     *q, *q, *q, *q, *q,
36     *q, *q, *q, *q, *q);
37   ++sigcnt;
38 }
39 
40 int main() {
41   signal(SIGPROF, SignalHandler);
42 
43   itimerval itv;
44   itv.it_interval.tv_sec = 0;
45   itv.it_interval.tv_usec = 100;
46   itv.it_value.tv_sec = 0;
47   itv.it_value.tv_usec = 100;
48   setitimer(ITIMER_PROF, &itv, NULL);
49 
50   void *p;
51   void **volatile q = &p;
52 
53   do {
54     f(false, 20,
55       nullptr, nullptr, nullptr, nullptr, nullptr,
56       nullptr, nullptr, nullptr, nullptr, nullptr,
57       nullptr, nullptr, nullptr, nullptr, nullptr,
58       nullptr, nullptr, nullptr, nullptr, nullptr);
59     f(true, 20,
60       *q, *q, *q, *q, *q,
61       *q, *q, *q, *q, *q,
62       *q, *q, *q, *q, *q,
63       *q, *q, *q, *q, *q);
64   } while (sigcnt < kSigCnt);
65 
66   itv.it_interval.tv_sec = 0;
67   itv.it_interval.tv_usec = 0;
68   itv.it_value.tv_sec = 0;
69   itv.it_value.tv_usec = 0;
70   setitimer(ITIMER_PROF, &itv, NULL);
71 
72   signal(SIGPROF, SIG_DFL);
73   return 0;
74 }
75