Changeset 224916 in webkit for trunk/Source/JavaScriptCore/bytecode/BytecodeDumper.cpp

Timestamp:

Nov 16, 2017, 7:08:10 AM (8 years ago)

Author:

[email protected]

Message:

Fix null pointer dereference in bytecodeDumper
​https://bugs.webkit.org/show_bug.cgi?id=179764

Reviewed by Mark Lam.

The problem was just a call to lastSeenCallee() that was unguarded by haveLastSeenCallee().

• bytecode/BytecodeDumper.cpp:

(JSC::BytecodeDumper<Block>::printCallOp):

File:

• trunk/Source/JavaScriptCore/bytecode/BytecodeDumper.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/bytecode/BytecodeDumper.cpp

@@ -587 +587 @@
 #if ENABLE(JIT)
         if (CallLinkInfo* info = map.get(CodeOrigin(location))) {
-            JSObject* object = info->lastSeenCallee();
-            if (auto* function = jsDynamicCast<JSFunction*>(*vm(), object))
-                out.printf(" jit(%p, exec %p)", function, function->executable());
-            else
-                out.printf(" jit(%p)", object);
+            if (info->haveLastSeenCallee()) {
+                JSObject* object = info->lastSeenCallee();
+                if (auto* function = jsDynamicCast<JSFunction*>(*vm(), object))
+                    out.printf(" jit(%p, exec %p)", function, function->executable());
+                else
+                    out.printf(" jit(%p)", object);
+            }
         }