From: Elliott Hughes <enh@google.com>
Date: Fri, 12 Apr 2013 18:51:51 +0000 (-0700)
Subject: More native stack dump hardening.
X-Git-Tag: android-x86-4.4-r1~28^2~9^2~44^2
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=46371593812d966c40e1ec4019e3c7c6613046a6;p=android-x86%2Fdalvik.git

More native stack dump hardening.

Threads just starting up or shutting down might not have any managed
stack frames, leading to a NULL "currFrame" frame pointer in the
interpreter stack.

Bug: 8596028
Change-Id: Ie24c8d5f8e78a5abe882a9e639046c03abb91649
---

diff --git a/vm/Thread.cpp b/vm/Thread.cpp
index aba98ab73..cfc43486d 100644
--- a/vm/Thread.cpp
+++ b/vm/Thread.cpp
@@ -3330,7 +3330,12 @@ static bool shouldShowNativeStack(Thread* thread) {
     // state THREAD_SUSPENDED if they're calling back into the VM, or THREAD_MONITOR
     // if they're blocked on a monitor, or one of the thread-startup states if
     // it's early enough in their life cycle (http://b/7432159).
-    const Method* currentMethod = SAVEAREA_FROM_FP(thread->interpSave.curFrame)->method;
+    u4* fp = thread->interpSave.curFrame;
+    if (fp == NULL) {
+        // The thread has no managed frames, so native frames are all there is.
+        return true;
+    }
+    const Method* currentMethod = SAVEAREA_FROM_FP(fp)->method;
     return currentMethod != NULL && dvmIsNativeMethod(currentMethod);
 }