From 9ea3169ca9db1712ed29f713af53bead6526d65e Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Sat, 20 Nov 2021 22:51:22 -0800
Subject: [PATCH] Do not allow modifying page sizes

---
 native/jni/magiskboot/bootimg.cpp | 5 +----
 native/jni/magiskboot/bootimg.hpp | 7 ++-----
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/native/jni/magiskboot/bootimg.cpp b/native/jni/magiskboot/bootimg.cpp
index 917a807fe..73365cbdf 100644
--- a/native/jni/magiskboot/bootimg.cpp
+++ b/native/jni/magiskboot/bootimg.cpp
@@ -94,7 +94,6 @@ void dyn_img_hdr::print() {
 
 void dyn_img_hdr::dump_hdr_file() {
     FILE *fp = xfopen(HEADER_FILE, "w");
-    fprintf(fp, "pagesize=%u\n", page_size());
     if (name())
         fprintf(fp, "name=%s\n", name());
     fprintf(fp, "cmdline=%.*s%.*s\n", BOOT_ARGS_SIZE, cmdline(), BOOT_EXTRA_ARGS_SIZE, extra_cmdline());
@@ -119,9 +118,7 @@ void dyn_img_hdr::dump_hdr_file() {
 
 void dyn_img_hdr::load_hdr_file() {
     parse_prop_file(HEADER_FILE, [=](string_view key, string_view value) -> bool {
-        if (key == "page_size") {
-            page_size() = parse_int(value);
-        } else if (key == "name" && name()) {
+        if (key == "name" && name()) {
             memset(name(), 0, 16);
             memcpy(name(), value.data(), value.length() > 15 ? 15 : value.length());
         } else if (key == "cmdline") {
diff --git a/native/jni/magiskboot/bootimg.hpp b/native/jni/magiskboot/bootimg.hpp
index 1c3d8e429..6929cb91f 100644
--- a/native/jni/magiskboot/bootimg.hpp
+++ b/native/jni/magiskboot/bootimg.hpp
@@ -351,7 +351,7 @@ struct dyn_img_hdr {
     decl_var(kernel_size, 32)
     decl_var(ramdisk_size, 32)
     decl_var(second_size, 32)
-    decl_var(page_size, 32)
+    decl_val(page_size, uint32_t)
     decl_val(header_version, uint32_t)
     decl_var(extra_size, 32)
     decl_var(os_version, 32)
@@ -489,11 +489,8 @@ struct dyn_img_v3 : public dyn_img_hdr_boot {
     impl_val(cmdline)
 
     // Make API compatible
-    uint32_t &page_size() override { page_sz = 4096; return page_sz; }
+    uint32_t page_size() override { return 4096; }
     char *extra_cmdline() override { return &v4_hdr->cmdline[BOOT_ARGS_SIZE]; }
-
-private:
-    uint32_t page_sz = 4096;
 };
 
 struct dyn_img_v4 : public dyn_img_v3 {