src/cpu/x86/vm/templateTable_x86_32.cpp

rev 5510 : 8027252: Crash in interpreter because get_unsigned_2_byte_index_at_bcp reads 4 bytes
Summary: Use 2-byte loads to load indexes from the byte code stream to avoid out of bounds reads.
Reviewed-by:

@@ -556,11 +556,11 @@
   __ movptr(rax, aaddress(rbx));
 }
 
 
 void TemplateTable::locals_index_wide(Register reg) {
-  __ movl(reg, at_bcp(2));
+  __ load_unsigned_short(reg, at_bcp(2));
   __ bswapl(reg);
   __ shrl(reg, 16);
   __ negptr(reg);
 }
 

@@ -1550,11 +1550,15 @@
                              InvocationCounter::counter_offset();
   const ByteSize inv_offset = MethodCounters::invocation_counter_offset() +
                               InvocationCounter::counter_offset();
 
   // Load up EDX with the branch displacement
+  if (is_wide) {
   __ movl(rdx, at_bcp(1));
+  } else {
+    __ load_signed_short(rdx, at_bcp(1));
+  }
   __ bswapl(rdx);
   if (!is_wide) __ sarl(rdx, 16);
   LP64_ONLY(__ movslq(rdx, rdx));