From c91ebfbcc118be728c7ecfbcc593cecb9b975619 Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Sat, 26 Sep 2020 14:36:57 -0700
Subject: [PATCH] Pad images to original sizes with zero

Close #2005
---
 native/jni/magiskboot/bootimg.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/native/jni/magiskboot/bootimg.cpp b/native/jni/magiskboot/bootimg.cpp
index 0c6944542..2832a02ca 100644
--- a/native/jni/magiskboot/bootimg.cpp
+++ b/native/jni/magiskboot/bootimg.cpp
@@ -524,6 +524,13 @@ void repack(const char* src_img, const char* out_img, bool nocomp) {
 		restore_buf(fd, LG_BUMP_MAGIC, 16);
 	}
 
+	// Pad image to at least original size
+	auto current_sz = lseek(fd, 0, SEEK_CUR);
+	if (current_sz < boot.map_size) {
+		int padding = boot.map_size - current_sz;
+		write_zero(fd, padding);
+	}
+
 	close(fd);
 
 	/*********************