GP-3770: Fixing Mach-o PRELINK check

Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/MachoLoader.java

@@ -90,7 +90,8 @@ public class MachoLoader extends AbstractLibrarySupportLoader {
 
 			// A Mach-O file may contain PRELINK information.  If so, we use a special
 			// program builder that knows how to deal with it.
-			if (MachoPrelinkUtils.isMachoPrelink(provider, true, monitor)) {
+			if (MachoPrelinkUtils.isMachoPrelink(provider, monitor) ||
+				MachoPrelinkUtils.isMachoFileset(provider)) {
 				MachoPrelinkProgramBuilder.buildProgram(program, provider, fileBytes, log, monitor);
 			}
 			else {

Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/MachoPrelinkUtils.java

@@ -37,23 +37,22 @@ import ghidra.util.task.TaskMonitor;
 public class MachoPrelinkUtils {
 
 	/**
-	 * Check to see if the given {@link ByteProvider} is a Mach-O PRELINK binary
+	 * Check to see if the given {@link ByteProvider} is a Mach-O PRELINK binary.
+	 * <p>
+	 * NOTE: This method will return false if the binary is a Mach-O file set.
 	 * 
 	 * @param provider The {@link ByteProvider} to check
-	 * @param allowFileset True if Mach-O file sets should be considered a PRELINK binary; 
-	 *   otherwise, false
 	 * @param monitor A monitor
 	 * @return True if the given {@link ByteProvider} is a Mach-O PRELINK binary; otherwise, false
 	 */
-	public static boolean isMachoPrelink(ByteProvider provider, boolean allowFileset,
+	public static boolean isMachoPrelink(ByteProvider provider, TaskMonitor monitor) {
-			TaskMonitor monitor) {
 		try {
 			MachHeader header = new MachHeader(provider);
 			boolean hasPrelinkSegment = new MachHeader(provider).parseSegments()
 					.stream()
 					.anyMatch(segment -> segment.getSegmentName().startsWith("__PRELINK"));
 			boolean hasFileSet = header.parseAndCheck(LoadCommandTypes.LC_FILESET_ENTRY);
-			return hasPrelinkSegment && allowFileset && hasFileSet;
+			return hasPrelinkSegment && !hasFileSet;
 		}
 		catch (MachException | IOException e) {
 			// Assume it's not a Mach-O PRELINK...fall through
@@ -61,6 +60,22 @@ public class MachoPrelinkUtils {
 		return false;
 	}
 
+	/**
+	 * Check to see if the given {@link ByteProvider} is a Mach-O file set
+	 * 
+	 * @param provider The {@link ByteProvider} to check
+	 * @return True if the given {@link ByteProvider} is a Mach-O file set; otherwise, false
+	 */
+	public static boolean isMachoFileset(ByteProvider provider) {
+		try {
+			return new MachHeader(provider).parseAndCheck(LoadCommandTypes.LC_FILESET_ENTRY);
+		}
+		catch (MachException | IOException e) {
+			// Assume it's not a Mach-O file set...fall through
+		}
+		return false;
+	}
+
 	/**
 	 * Parses the provider looking for PRELINK XML.
 	 * 

Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/fileset/MachoFileSetFileSystemFactory.java

@@ -18,9 +18,7 @@ package ghidra.file.formats.ios.fileset;
 import java.io.IOException;
 
 import ghidra.app.util.bin.ByteProvider;
-import ghidra.app.util.bin.format.macho.MachException;
+import ghidra.app.util.opinion.MachoPrelinkUtils;
-import ghidra.app.util.bin.format.macho.MachHeader;
-import ghidra.app.util.bin.format.macho.commands.LoadCommandTypes;
 import ghidra.formats.gfilesystem.FSRLRoot;
 import ghidra.formats.gfilesystem.FileSystemService;
 import ghidra.formats.gfilesystem.factory.GFileSystemFactoryByteProvider;
@@ -46,12 +44,6 @@ public class MachoFileSetFileSystemFactory implements
 	@Override
 	public boolean probe(ByteProvider byteProvider, FileSystemService fsService,
 			TaskMonitor monitor) throws IOException, CancelledException {
-		try {
+		return MachoPrelinkUtils.isMachoFileset(byteProvider);
-			return new MachHeader(byteProvider).parseAndCheck(LoadCommandTypes.LC_FILESET_ENTRY);
-		}
-		catch (MachException e) {
-			// Assume it's not a Mach-O...fall through
-		}
-		return false;
 	}
 }

Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/prelink/MachoPrelinkFileSystem.java

@@ -75,7 +75,7 @@ public class MachoPrelinkFileSystem extends GFileSystemBase implements GFileSyst
 
 	@Override
 	public boolean isValid(TaskMonitor monitor) throws IOException {
-		return MachoPrelinkUtils.isMachoPrelink(provider, false, monitor);
+		return MachoPrelinkUtils.isMachoPrelink(provider, monitor);
 	}
 
 	@Override