Don't assert if materializing before seeing any function bodies

This assert was reachable from user input. A minimized test case (no
FUNCTION_BLOCK_ID record) is attached.

Bug found with afl-fuzz

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251910 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index 74a5553ce6e4b018caf8f79fddc5ff0b52bf2b19..c874a84e0cbe326305c40fb22df0a30058461768 100644 (file)
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3055,7 +3055,9 @@ std::error_code BitcodeReader::rememberAndSkipFunctionBodies() {
   if (Stream.AtEndOfStream())
     return error("Could not find function in stream");
 
-  assert(SeenFirstFunctionBody);
+  if (!SeenFirstFunctionBody)
+    return error("Trying to materialize functions before seeing function blocks");
+
   // An old bitcode file with the symbol table at the end would have
   // finished the parse greedily.
   assert(SeenValueSymbolTable);

diff --git a/test/Bitcode/Inputs/invalid-no-function-block.bc b/test/Bitcode/Inputs/invalid-no-function-block.bc
new file mode 100644 (file)
index 0000000..52b6558
Binary files /dev/null and b/test/Bitcode/Inputs/invalid-no-function-block.bc differ

diff --git a/test/Bitcode/invalid.test b/test/Bitcode/invalid.test
index 69104046df20256fa7cafdde5c1d1f3f0d75590c..24ccd8bccd5bd86ec9cb2167e28b761becaba2c5 100644 (file)
--- a/test/Bitcode/invalid.test
+++ b/test/Bitcode/invalid.test
@@ -207,3 +207,8 @@ RUN: not llvm-dis -disable-output %p/Inputs/invalid-alias-type-mismatch.bc 2>&1
 RUN:   FileCheck --check-prefix=ALIAS-TYPE-MISMATCH %s
 
 ALIAS-TYPE-MISMATCH: Alias and aliasee types don't match
+
+RUN: not llvm-dis -disable-output %p/Inputs/invalid-no-function-block.bc 2>&1 | \
+RUN:   FileCheck --check-prefix=NO-FUNCTION-BLOCK %s
+
+NO-FUNCTION-BLOCK: Trying to materialize functions before seeing function blocks