From 17cbb3eab0a725b7c9946ceda54dbeb9c639b29d Mon Sep 17 00:00:00 2001
From: S-trace <S-trace@list.ru>
Date: Fri, 3 Jan 2020 04:16:22 +0300
Subject: [PATCH] core: Fix possible NPE in DebugInfoParser.addrChange()

This may happen because MethodNode.unloadInsnArr() call from BlockSplitter.visit() - after it instructions[] become null.
So, try to reload method before processing its instructions array and bail if insnArr still null even after reloading method.
---
 .../java/jadx/core/dex/nodes/MethodNode.java   | 18 +++++++++++-------
 .../debuginfo/DebugInfoParseVisitor.java       |  9 +++++++++
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java b/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
index 14c287b4e..889f2ff2c 100644
--- a/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
+++ b/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
@@ -155,13 +155,8 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 	public void checkInstructions() {
 		List<RegisterArg> list = new ArrayList<>();
 		if (instructions == null) {
-			LOG.debug("Instructions == null, reloading method {}.{}", getClass().getName(), getName());
-			unload();
-			try {
-				load();
-			} catch (DecodeException e) {
-				throw new JadxRuntimeException("Failed to reload method " + getClass().getName() + "." + getName());
-			}
+			LOG.debug("instructions == null, reloading method {}.{}", getClass().getName(), getName());
+			reload();
 		}
 		for (InsnNode insnNode : instructions) {
 			if (insnNode == null) {
@@ -182,6 +177,15 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 		}
 	}
 
+	public void reload() {
+		unload();
+		try {
+			load();
+		} catch (DecodeException e) {
+			throw new JadxRuntimeException("Failed to reload method " + getClass().getName() + "." + getName());
+		}
+	}
+
 	public void initMethodTypes() {
 		List<ArgType> types = parseSignature();
 		if (types == null) {
diff --git a/jadx-core/src/main/java/jadx/core/dex/visitors/debuginfo/DebugInfoParseVisitor.java b/jadx-core/src/main/java/jadx/core/dex/visitors/debuginfo/DebugInfoParseVisitor.java
index 3bc4368ae..e21b5734d 100644
--- a/jadx-core/src/main/java/jadx/core/dex/visitors/debuginfo/DebugInfoParseVisitor.java
+++ b/jadx-core/src/main/java/jadx/core/dex/visitors/debuginfo/DebugInfoParseVisitor.java
@@ -48,6 +48,15 @@ public class DebugInfoParseVisitor extends AbstractVisitor {
 
 	private void processDebugInfo(MethodNode mth, int debugOffset) {
 		InsnNode[] insnArr = mth.getInstructions();
+		if (insnArr == null) {
+			LOG.debug("insnArr == null, reloading method {}.{}", getClass().getName(), mth.getName());
+			mth.reload();
+			insnArr = mth.getInstructions();
+		}
+		if (insnArr == null) {
+			LOG.error("insnArr == null even after reloading method {}.{} - bailing", getClass().getName(), mth.getName());
+			return;
+		}
 		DebugInfoParser debugInfoParser = new DebugInfoParser(mth, debugOffset, insnArr);
 		List<LocalVar> localVars = debugInfoParser.process();
 		attachDebugInfo(mth, localVars, insnArr);