1 files changed, 50 insertions, 0 deletions
diff --git a/lib/msan/lit_tests/Linux/syscalls.cc b/lib/msan/lit_tests/Linux/syscalls.cc
new file mode 100644
index 000000000000..c12eda39189e
--- /dev/null
+++ b/lib/msan/lit_tests/Linux/syscalls.cc
@@ -0,0 +1,50 @@
+// RUN: %clangxx_msan -m64 -O0 %s -o %t && %t 2>&1
+// RUN: %clangxx_msan -m64 -O3 %s -o %t && %t 2>&1
+
+#include <assert.h>
+#include <errno.h>
+#include <glob.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <sanitizer/linux_syscall_hooks.h>
+#include <sanitizer/msan_interface.h>
+
+/* Test the presence of __sanitizer_syscall_ in the tool runtime, and general
+   sanity of their behaviour. */
+
+int main(int argc, char *argv[]) {
+  char buf[1000];
+  const int kTen = 10;
+  memset(buf, 0, sizeof(buf));
+  __msan_unpoison(buf, sizeof(buf));
+  __sanitizer_syscall_pre_recvmsg(0, buf, 0);
+  __sanitizer_syscall_pre_rt_sigpending(buf, kTen);
+  __sanitizer_syscall_pre_getdents(0, buf, kTen);
+  __sanitizer_syscall_pre_getdents64(0, buf, kTen);
+
+  __msan_unpoison(buf, sizeof(buf));
+  __sanitizer_syscall_post_recvmsg(0, 0, buf, 0);
+  __sanitizer_syscall_post_rt_sigpending(-1, buf, kTen);
+  __sanitizer_syscall_post_getdents(0, 0, buf, kTen);
+  __sanitizer_syscall_post_getdents64(0, 0, buf, kTen);
+  assert(__msan_test_shadow(buf, sizeof(buf)) == -1);
+
+  __msan_unpoison(buf, sizeof(buf));
+  __sanitizer_syscall_post_recvmsg(kTen, 0, buf, 0);
+
+  // Tell the kernel that the output struct size is 10 bytes, verify that those
+  // bytes are unpoisoned, and the next byte is not.
+  __msan_poison(buf, kTen + 1);
+  __sanitizer_syscall_post_rt_sigpending(0, buf, kTen);
+  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);
+
+  __msan_poison(buf, kTen + 1);
+  __sanitizer_syscall_post_getdents(kTen, 0, buf, kTen);
+  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);
+
+  __msan_poison(buf, kTen + 1);
+  __sanitizer_syscall_post_getdents64(kTen, 0, buf, kTen);
+  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);
+  return 0;
+}