Restore runtime flag validation and unbump bytecode version

Summary: Temporarily avoid incrementing bytecode version. Reviewed By: avp Differential Revision: D22055456 fbshipit-source-id: 4aa3e0e153a79f6d416ea270cc8a3c672f9d6ee9
apurvsibal · Jun 16, 2020 · e9c80a0 · e9c80a0
1 parent 9a7d040
commit e9c80a0
Show file tree

Hide file tree

Showing 3 changed files with 14 additions and 9 deletions.
diff --git a/include/hermes/BCGen/HBC/BytecodeFileFormat.h b/include/hermes/BCGen/HBC/BytecodeFileFormat.h
@@ -29,8 +29,8 @@ const static uint64_t MAGIC = 0x1F1903C103BC1FC6;
 const static uint64_t DELTA_MAGIC = ~MAGIC;
 
 // Bytecode version generated by this version of the compiler.
-// Updated: Jun 12, 2020
-const static uint32_t BYTECODE_VERSION = 75;
+// Updated: Jun 15, 2020
+const static uint32_t BYTECODE_VERSION = 74;
 
 /// Property cache index which indicates no caching.
 static constexpr uint8_t PROPERTY_CACHING_DISABLED = 0;

diff --git a/lib/VM/JSRegExp.cpp b/lib/VM/JSRegExp.cpp
@@ -136,12 +136,20 @@ ExecutionStatus JSRegExp::initialize(
       res != ExecutionStatus::EXCEPTION && *res &&
       "defineOwnProperty() failed");
 
+  // Validate flags.
+  llvm::SmallVector<char16_t, 16> flagsText16;
+  flags->copyUTF16String(flagsText16);
+
+  auto sflags = regex::SyntaxFlags::fromString(flagsText16);
+  if (!sflags) {
+    runtime->raiseSyntaxError("Invalid RegExp: Invalid flags");
+    return ExecutionStatus::EXCEPTION;
+  }
+  selfHandle->syntaxFlags_ = *sflags;
+
   if (bytecode) {
     return selfHandle->initializeBytecode(*bytecode, runtime);
   } else {
-    llvm::SmallVector<char16_t, 6> flagsText16;
-    flags->copyUTF16String(flagsText16);
-
     llvm::SmallVector<char16_t, 16> patternText16;
     pattern->copyUTF16String(patternText16);
 
@@ -169,9 +177,6 @@ ExecutionStatus JSRegExp::initializeBytecode(
     runtime->raiseRangeError("RegExp size overflow");
     return ExecutionStatus::EXCEPTION;
   }
-  auto header =
-      reinterpret_cast<const regex::RegexBytecodeHeader *>(bytecode.data());
-  syntaxFlags_ = regex::SyntaxFlags::fromByte(header->syntaxFlags);
   bytecodeSize_ = sz;
   bytecode_ = (uint8_t *)checkedMalloc(sz);
   memcpy(bytecode_, bytecode.data(), sz);

diff --git a/tools/hbc-attribute/hbc-attribute.cpp b/tools/hbc-attribute/hbc-attribute.cpp
@@ -68,7 +68,7 @@ using SLG = hermes::hbc::SerializedLiteralGenerator;
  * If you have added or modified sections, make sure they're counted properly.
  */
 static_assert(
-    BYTECODE_VERSION == 75,
+    BYTECODE_VERSION == 74,
     "Bytecode version changed. Please verify that hbc-attribute counts correctly..");
 
 static llvm::cl::opt<std::string> InputFilename(