1 files changed, 45 insertions, 0 deletions
diff --git a/test/msan/mmap.cc b/test/msan/mmap.cc
new file mode 100644
index 0000000000000..c09fcb76a8279
--- /dev/null
+++ b/test/msan/mmap.cc
@@ -0,0 +1,45 @@
+// Test that mmap (without MAP_FIXED) always returns valid application addresses.
+// RUN: %clangxx_msan -O0 %s -o %t && %run %t
+// RUN: %clangxx_msan -O0 -fsanitize-memory-track-origins %s -o %t && %run %t
+
+#include <assert.h>
+#include <errno.h>
+#include <stdint.h>
+#include <sys/mman.h>
+#include <stdio.h>
+
+bool AddrIsApp(void *p) {
+  uintptr_t addr = (uintptr_t)p;
+#if defined(__FreeBSD__) && defined(__x86_64__)
+  return addr < 0x010000000000ULL || addr >= 0x600000000000ULL;
+#elif defined(__x86_64__)
+  return addr >= 0x600000000000ULL;
+#elif defined(__mips64)
+  return addr >= 0x00e000000000ULL;
+#elif defined(__powerpc64__)
+  return addr < 0x000100000000ULL || addr >= 0x300000000000ULL;
+#endif
+}
+
+int main() {
+  // Large enough to quickly exhaust the entire address space.
+#if defined(__mips64)
+  const size_t kMapSize = 0x100000000ULL;
+#else
+  const size_t kMapSize = 0x1000000000ULL;
+#endif
+  int success_count = 0;
+  while (true) {
+    void *p = mmap(0, kMapSize, PROT_WRITE,
+                   MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
+    printf("%p\n", p);
+    if (p == MAP_FAILED) {
+      assert(errno == ENOMEM);
+      break;
+    }
+    assert(AddrIsApp(p));
+    success_count++;
+  }
+  printf("successful mappings: %d\n", success_count);
+  assert(success_count > 5);
+}