diff --git a/llvm/lib/Support/ARMAttributeParser.cpp b/llvm/lib/Support/ARMAttributeParser.cpp
index 08b939a..65ee51f 100644
--- a/llvm/lib/Support/ARMAttributeParser.cpp
+++ b/llvm/lib/Support/ARMAttributeParser.cpp
@@ -709,6 +709,12 @@
       SW->indent();
     }
 
+    if (SectionLength == 0 || (SectionLength + Offset) > Section.size()) {
+      errs() << "invalid subsection length " << SectionLength << " at offset "
+             << Offset << "\n";
+      return;
+    }
+
     ParseSubsection(Section.data() + Offset, SectionLength);
     Offset = Offset + SectionLength;