diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3407,9 +3407,12 @@
 
   // Record[16] is the address space number.
 
-  // Check whether we have enough values to read a partition name.
-  if (Record.size() > 18)
+  // Check whether we have enough values to read a partition name. Also make
+  // sure Strtab has enough values.
+  if (Record.size() > 18 && Strtab.data() &&
+      Record[17] + Record[18] <= Strtab.size()) {
     Func->setPartition(StringRef(Strtab.data() + Record[17], Record[18]));
+  }
 
   ValueList.push_back(Func);
 
diff --git a/llvm/test/Bitcode/invalid-record-strtab.ll b/llvm/test/Bitcode/invalid-record-strtab.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Bitcode/invalid-record-strtab.ll
@@ -0,0 +1,5 @@
+; Bitcode with an invalid record that indexes a name outside of strtab.
+
+; RUN: not llvm-dis %s.bc -o - 2>&1 | FileCheck %s
+
+; CHECK: error: Invalid record
diff --git a/llvm/test/Bitcode/invalid-record-strtab.ll.bc b/llvm/test/Bitcode/invalid-record-strtab.ll.bc
new file mode 100644
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000
GIT binary patch
literal 0
Hc$@<O00001

literal 0
Hc$@<O00001