fix: use variable length encoding instead short for offsets (can over…

…flow) (#1489)

jadx-core/src/main/java/jadx/api/JavaClass.java

@@ -206,7 +206,6 @@ public List<Integer> getUsePlacesFor(ICodeInfo codeInfo, JavaNode javaNode) {
 				// ignore declarations and offset annotations
 				continue;
 			}
-			// ignore declarations
 			JavaNode annNode = rootDec.getJavaNodeByCodeAnnotation(codeInfo, ann);
 			if (annNode == null && LOG.isDebugEnabled()) {
 				LOG.debug("Failed to resolve code annotation, cls: {}, pos: {}, ann: {}", this, entry.getKey(), ann);

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/CodeMetadataAdapter.java

@@ -25,6 +25,8 @@
 import jadx.core.utils.files.FileUtils;
 import jadx.gui.utils.codecache.disk.adapters.CodeAnnotationAdapter;
 
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.readUVInt;
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.writeUVInt;
 import static java.nio.file.StandardOpenOption.CREATE;
 import static java.nio.file.StandardOpenOption.TRUNCATE_EXISTING;
 import static java.nio.file.StandardOpenOption.WRITE;
@@ -68,8 +70,8 @@ public ICodeInfo readAndBuild(Path metadataFile, String code) {
 	private void writeLines(DataOutput out, Map<Integer, Integer> lines) throws IOException {
 		out.writeInt(lines.size());
 		for (Map.Entry<Integer, Integer> entry : lines.entrySet()) {
-			out.writeShort(entry.getKey());
-			out.writeShort(entry.getValue());
+			writeUVInt(out, entry.getKey());
+			writeUVInt(out, entry.getValue());
 		}
 	}
 
@@ -80,8 +82,8 @@ private Map<Integer, Integer> readLines(DataInput in) throws IOException {
 		}
 		Map<Integer, Integer> lines = new HashMap<>(size);
 		for (int i = 0; i < size; i++) {
-			int key = in.readShort();
-			int value = in.readShort();
+			int key = readUVInt(in);
+			int value = readUVInt(in);
 			lines.put(key, value);
 		}
 		return lines;
@@ -90,7 +92,7 @@ private Map<Integer, Integer> readLines(DataInput in) throws IOException {
 	private void writeAnnotations(DataOutputStream out, Map<Integer, ICodeAnnotation> annotations) throws IOException {
 		out.writeInt(annotations.size());
 		for (Map.Entry<Integer, ICodeAnnotation> entry : annotations.entrySet()) {
-			out.writeInt(entry.getKey());
+			writeUVInt(out, entry.getKey());
 			codeAnnotationAdapter.write(out, entry.getValue());
 		}
 	}
@@ -102,7 +104,7 @@ private Map<Integer, ICodeAnnotation> readAnnotations(DataInputStream in) throws
 		}
 		Map<Integer, ICodeAnnotation> map = new HashMap<>(size);
 		for (int i = 0; i < size; i++) {
-			int pos = in.readInt();
+			int pos = readUVInt(in);
 			ICodeAnnotation ann = codeAnnotationAdapter.read(in);
 			if (ann != null) {
 				map.put(pos, ann);

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/DiskCodeCache.java

@@ -37,7 +37,7 @@
 public class DiskCodeCache implements ICodeCache {
 	private static final Logger LOG = LoggerFactory.getLogger(DiskCodeCache.class);
 
-	private static final int DATA_FORMAT_VERSION = 8;
+	private static final int DATA_FORMAT_VERSION = 9;
 
 	private final Path srcDir;
 	private final Path metaDir;

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/DataAdapterHelper.java

@@ -0,0 +1,63 @@
+package jadx.gui.utils.codecache.disk.adapters;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+import org.jetbrains.annotations.Nullable;
+
+public class DataAdapterHelper {
+
+	public static void writeNullableUTF(DataOutput out, @Nullable String str) throws IOException {
+		if (str == null) {
+			out.writeByte(0);
+		} else {
+			out.writeByte(1);
+			out.writeUTF(str);
+		}
+	}
+
+	public static @Nullable String readNullableUTF(DataInput in) throws IOException {
+		if (in.readByte() == 0) {
+			return null;
+		}
+		return in.readUTF();
+	}
+
+	/**
+	 * Write unsigned variable length integer (ULEB128 encoding)
+	 */
+	public static void writeUVInt(DataOutput out, int val) throws IOException {
+		if (val < 0) {
+			throw new IllegalArgumentException("Expect value >= 0, got: " + val);
+		}
+		int current = val;
+		int next = val;
+		while (true) {
+			next >>>= 7;
+			if (next == 0) {
+				// last byte
+				out.writeByte(current & 0x7f);
+				return;
+			}
+			out.writeByte((current & 0x7f) | 0x80);
+			current = next;
+		}
+	}
+
+	/**
+	 * Read unsigned variable length integer (ULEB128 encoding)
+	 */
+	public static int readUVInt(DataInput in) throws IOException {
+		int result = 0;
+		int shift = 0;
+		while (true) {
+			byte v = in.readByte();
+			result |= (v & (byte) 0x7f) << shift;
+			shift += 7;
+			if ((v & 0x80) != 0x80) {
+				return result;
+			}
+		}
+	}
+}

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/InsnCodeOffsetAdapter.java

@@ -12,11 +12,11 @@ public class InsnCodeOffsetAdapter implements DataAdapter<InsnCodeOffset> {
 
 	@Override
 	public void write(DataOutput out, InsnCodeOffset value) throws IOException {
-		out.writeShort(value.getOffset());
+		DataAdapterHelper.writeUVInt(out, value.getOffset());
 	}
 
 	@Override
 	public InsnCodeOffset read(DataInput in) throws IOException {
-		return new InsnCodeOffset(in.readShort());
+		return new InsnCodeOffset(DataAdapterHelper.readUVInt(in));
 	}
 }

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/NodeDeclareRefAdapter.java

@@ -21,13 +21,13 @@ public void write(DataOutput out, NodeDeclareRef value) throws IOException {
 			throw new RuntimeException("Null node in NodeDeclareRef");
 		}
 		refAdapter.write(out, node);
-		out.writeShort(value.getDefPos());
+		DataAdapterHelper.writeUVInt(out, value.getDefPos());
 	}
 
 	@Override
 	public NodeDeclareRef read(DataInput in) throws IOException {
 		ICodeNodeRef ref = (ICodeNodeRef) refAdapter.read(in);
-		int defPos = in.readShort();
+		int defPos = DataAdapterHelper.readUVInt(in);
 		NodeDeclareRef nodeDeclareRef = new NodeDeclareRef(ref);
 		nodeDeclareRef.setDefPos(defPos);
 		// restore def position if loading metadata without actual decompilation

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/VarNodeAdapter.java

@@ -8,7 +8,12 @@
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.nodes.MethodNode;
 
-public class VarNodeAdapter extends BaseDataAdapter<VarNode> {
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.readNullableUTF;
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.readUVInt;
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.writeNullableUTF;
+import static jadx.gui.utils.codecache.disk.adapters.DataAdapterHelper.writeUVInt;
+
+public class VarNodeAdapter implements DataAdapter<VarNode> {
 	private final MethodNodeAdapter mthAdapter;
 
 	public VarNodeAdapter(MethodNodeAdapter mthAdapter) {
@@ -18,17 +23,17 @@ public VarNodeAdapter(MethodNodeAdapter mthAdapter) {
 	@Override
 	public void write(DataOutput out, VarNode value) throws IOException {
 		mthAdapter.write(out, value.getMth());
-		out.writeShort(value.getReg());
-		out.writeShort(value.getSsa());
+		writeUVInt(out, value.getReg());
+		writeUVInt(out, value.getSsa());
 		ArgTypeAdapter.INSTANCE.write(out, value.getType());
 		writeNullableUTF(out, value.getName());
 	}
 
 	@Override
 	public VarNode read(DataInput in) throws IOException {
 		MethodNode mth = mthAdapter.read(in);
-		int reg = in.readShort();
-		int ssa = in.readShort();
+		int reg = readUVInt(in);
+		int ssa = readUVInt(in);
 		ArgType type = ArgTypeAdapter.INSTANCE.read(in);
 		String name = readNullableUTF(in);
 		return new VarNode(mth, reg, ssa, type, name);

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/VarRefAdapter.java

@@ -6,21 +6,19 @@
 
 import jadx.api.metadata.annotations.VarRef;
 
-public class VarRefAdapter extends BaseDataAdapter<VarRef> {
+public class VarRefAdapter implements DataAdapter<VarRef> {
 
 	public static final VarRefAdapter INSTANCE = new VarRefAdapter();
 
 	@Override
 	public void write(DataOutput out, VarRef value) throws IOException {
 		int refPos = value.getRefPos();
-		if (refPos <= 0) {
-			throw new RuntimeException("Variable refPos is invalid: " + value);
-		}
-		out.writeInt(refPos);
+		DataAdapterHelper.writeUVInt(out, refPos);
 	}
 
 	@Override
 	public VarRef read(DataInput in) throws IOException {
-		return VarRef.fromPos(in.readInt());
+		int refPos = DataAdapterHelper.readUVInt(in);
+		return VarRef.fromPos(refPos);
 	}
 }

jadx-gui/src/test/java/jadx/gui/utils/codecache/disk/adapters/DataAdapterHelperTest.java

@@ -0,0 +1,40 @@
+package jadx.gui.utils.codecache.disk.adapters;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DataAdapterHelperTest {
+
+	@Test
+	void uvInt() throws IOException {
+		checkUVIntFor(0);
+		checkUVIntFor(7);
+		checkUVIntFor(0x7f);
+		checkUVIntFor(0x80);
+		checkUVIntFor(0x256);
+		checkUVIntFor(Byte.MAX_VALUE);
+		checkUVIntFor(Short.MAX_VALUE);
+		checkUVIntFor(Integer.MAX_VALUE);
+	}
+
+	private void checkUVIntFor(int val) throws IOException {
+		assertThat(writeReadUVInt(val)).isEqualTo(val);
+	}
+
+	private int writeReadUVInt(int val) throws IOException {
+		ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
+		DataOutputStream out = new DataOutputStream(byteOut);
+		DataAdapterHelper.writeUVInt(out, val);
+
+		DataInput in = new DataInputStream(new ByteArrayInputStream(byteOut.toByteArray()));
+		return DataAdapterHelper.readUVInt(in);
+	}
+}