2 files changed, 14 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 58e552710b7..3ad8e145815 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -2079,7 +2079,10 @@ void FunctionStackPoisoner::poisonStack() {
   for (AllocaInst *AI : AllocaVec) {
     ASanStackVariableDescription D = {AI->getName().data(),
                                       ASan.getAllocaSizeInBytes(*AI),
-                                      AI->getAlignment(), AI, 0};
+                                      0,
+                                      AI->getAlignment(),
+                                      AI,
+                                      0};
     SVD.push_back(D);
   }
   // Minimal header size (left redzone) is 4 pointers,
diff --git a/llvm/lib/Transforms/Utils/ASanStackFrameLayout.cpp b/llvm/lib/Transforms/Utils/ASanStackFrameLayout.cpp
index 7e50d4bb447..8e2ff7f25a2 100644
--- a/llvm/lib/Transforms/Utils/ASanStackFrameLayout.cpp
+++ b/llvm/lib/Transforms/Utils/ASanStackFrameLayout.cpp
@@ -81,19 +81,26 @@ ComputeASanStackFrameLayout(SmallVectorImpl<ASanStackVariableDescription> &Vars,
     assert(Layout->FrameAlignment >= Alignment);
     assert((Offset % Alignment) == 0);
     assert(Size > 0);
+    assert(Vars[i].LifetimeSize <= Size);
     StackDescription << " " << Offset << " " << Size << " " << strlen(Name)
                      << " " << Name;
     size_t NextAlignment = IsLast ? Granularity
                    : std::max(Granularity, Vars[i + 1].Alignment);
     size_t SizeWithRedzone = VarAndRedzoneSize(Vars[i].Size, NextAlignment);
-    SB.insert(SB.end(), Size / Granularity, 0);
-    if (Size % Granularity)
-      SB.insert(SB.end(), Size % Granularity);
+    size_t LifetimeShadowSize =
+        (Vars[i].LifetimeSize + Granularity - 1) / Granularity;
+    SB.insert(SB.end(), LifetimeShadowSize, kAsanStackUseAfterScopeMagic);
+    if (Size / Granularity >= LifetimeShadowSize) {
+      SB.insert(SB.end(), Size / Granularity - LifetimeShadowSize, 0);
+      if (Size % Granularity)
+        SB.insert(SB.end(), Size % Granularity);
+    }
     SB.insert(SB.end(), (SizeWithRedzone - Size) / Granularity,
         IsLast ? kAsanStackRightRedzoneMagic
         : kAsanStackMidRedzoneMagic);
     Vars[i].Offset = Offset;
     Offset += SizeWithRedzone;
+    assert(Offset == SB.size() * Granularity);
   }
   if (Offset % MinHeaderSize) {
     size_t ExtraRedzone = MinHeaderSize - (Offset % MinHeaderSize);