1// RUN: %clangxx_msan -DPRE1 -O0 %s -o %t && not %run %t 2>&1
2// RUN: %clangxx_msan -DPRE2 -O0 %s -o %t && not %run %t 2>&1
3// RUN: %clangxx_msan -DPRE3 -O0 %s -o %t && not %run %t 2>&1
4// RUN: %clangxx_msan -O0 %s -o %t && %run %t 2>&1
5
6#include <assert.h>
7#include <signal.h>
8#include <string.h>
9
10#include <sanitizer/linux_syscall_hooks.h>
11#include <sanitizer/msan_interface.h>
12
13struct my_kernel_sigaction {
14#if defined(__mips__)
15 long flags, handler;
16#else
17 long handler, flags, restorer;
18#endif
19 uint64_t mask[20]; // larger than any known platform
20};
21
22int main() {
23 my_kernel_sigaction act = {}, oldact = {};
24
25#if defined(PRE1)
26 __msan_poison(&act.handler, sizeof(act.handler));
27 __sanitizer_syscall_pre_rt_sigaction(SIGUSR1, &act, &oldact, 20 * 8);
28#elif defined(PRE2)
29 __msan_poison(&act.flags, sizeof(act.flags));
30 __sanitizer_syscall_pre_rt_sigaction(SIGUSR1, &act, &oldact, 20 * 8);
31#elif defined(PRE3)
32 __msan_poison(&act.mask, 1);
33 __sanitizer_syscall_pre_rt_sigaction(SIGUSR1, &act, &oldact, 20 * 8);
34#else
35 // Uninit past the end of the mask is ignored.
36 __msan_poison(a: ((char *)&act.mask) + 5, size: 1);
37 __sanitizer_syscall_pre_rt_sigaction(SIGUSR1, &act, &oldact, 5);
38
39 memset(s: &act, c: 0, n: sizeof(act));
40 __msan_poison(a: &oldact, size: sizeof(oldact));
41 __sanitizer_syscall_post_rt_sigaction(0, SIGUSR1, &act, &oldact, 5);
42#if defined(__mips__)
43 assert(__msan_test_shadow(&oldact, sizeof(oldact)) == sizeof(long)*2 + 5);
44#else
45 assert(__msan_test_shadow(&oldact, sizeof(oldact)) == sizeof(long)*3 + 5);
46#endif
47#endif
48}
49

source code of compiler-rt/test/msan/Linux/syscalls_sigaction.cpp