ASAN: Support detect_invalid_pointer_pairs=1 with detect_stack_use_after_return=1

Do not crash when AsanThread::GetStackVariableShadowStart does not find
a variable for a pointer on a shadow stack.

Cherry-pick from ad2be02a833e56f7fe280797280b219eb3312621.

Differential Revision: https://reviews.llvm.org/D89552

diff --git a/libsanitizer/asan/asan_thread.cpp b/libsanitizer/asan/asan_thread.cpp
index f0df8bd4b374dd3bac528af5b121f14b2bdf5d33..58cdc29d365ad64aab8fb58e1147ffb02be8a8ef 100644 (file)
--- a/libsanitizer/asan/asan_thread.cpp
+++ b/libsanitizer/asan/asan_thread.cpp
@@ -366,7 +366,9 @@ uptr AsanThread::GetStackVariableShadowStart(uptr addr) {
     bottom = stack_bottom();
   } else if (has_fake_stack()) {
     bottom = fake_stack()->AddrIsInFakeStack(addr);
-    CHECK(bottom);
+    if (bottom == 0) {
+      return 0;
+    }
   } else {
     return 0;
   }