1 files changed, 50 insertions, 0 deletions
diff --git a/test/asan/TestCases/Posix/high-address-dereference.c b/test/asan/TestCases/Posix/high-address-dereference.c
new file mode 100644
index 000000000..785033028
--- /dev/null
+++ b/test/asan/TestCases/Posix/high-address-dereference.c
@@ -0,0 +1,50 @@
+// On x86_64, the kernel does not provide the faulting address for dereferences
+// of addresses greater than the 48-bit hardware addressable range, i.e.,
+// `siginfo.si_addr` is zero in ASan's SEGV signal handler. This test checks
+// that ASan does not misrepresent such cases as "NULL dereferences".
+
+// REQUIRES: x86_64-target-arch
+// RUN: %clang_asan %s -o %t
+// RUN: export %env_asan_opts=print_scariness=1
+// RUN: not %run %t 0x0000000000000000 2>&1 | FileCheck %s --check-prefixes=ZERO,HINT-PAGE0
+// RUN: not %run %t 0x0000000000000FFF 2>&1 | FileCheck %s --check-prefixes=LOW1,HINT-PAGE0
+// RUN: not %run %t 0x0000000000001000 2>&1 | FileCheck %s --check-prefixes=LOW2,HINT-NONE
+// RUN: not %run %t 0x4141414141414141 2>&1 | FileCheck %s --check-prefixes=HIGH,HINT-HIGHADDR
+// RUN: not %run %t 0xFFFFFFFFFFFFFFFF 2>&1 | FileCheck %s --check-prefixes=MAX,HINT-HIGHADDR
+
+#include <stdint.h>
+#include <stdlib.h>
+
+int main(int argc, const char *argv[]) {
+  const char *hex = argv[1];
+  uint64_t *addr = (uint64_t *)strtoull(hex, NULL, 16);
+  uint64_t x = *addr;  // segmentation fault
+  return x;
+}
+
+// ZERO:  SEGV on unknown address 0x000000000000 (pc
+// LOW1:  SEGV on unknown address 0x000000000fff (pc
+// LOW2:  SEGV on unknown address 0x000000001000 (pc
+// HIGH:  SEGV on unknown address (pc
+// MAX:   SEGV on unknown address (pc
+
+// HINT-PAGE0-NOT: Hint: this fault was caused by a dereference of a high value address
+// HINT-PAGE0:     Hint: address points to the zero page.
+
+// HINT-NONE-NOT:  Hint: this fault was caused by a dereference of a high value address
+// HINT-NONE-NOT:  Hint: address points to the zero page.
+
+// HINT-HIGHADDR:     Hint: this fault was caused by a dereference of a high value address
+// HINT-HIGHADDR-NOT: Hint: address points to the zero page.
+
+// ZERO:  SCARINESS: 10 (null-deref)
+// LOW1:  SCARINESS: 10 (null-deref)
+// LOW2:  SCARINESS: 20 (wild-addr-read)
+// HIGH:  SCARINESS: 20 (wild-addr-read)
+// MAX:   SCARINESS: 20 (wild-addr-read)
+
+// TODO: Currently, register values are only printed on Mac.  Once this changes,
+//       remove the 'TODO_' prefix in the following lines.
+// TODO_HIGH,TODO_MAX: Register values:
+// TODO_HIGH: = 0x4141414141414141
+// TODO_MAX:  = 0xffffffffffffffff