fix: 修复当节头大小为0时，乱写point_to_raw_data的问题。

src-tauri/src/pe_parse/pe.rs

@@ -1,12 +1,10 @@
-use memmap2::MmapMut;
-
 use super::{
     error::{MutablePEError, PEParseError},
     header::*,
 };
 use std::{
-    mem::{self, offset_of},
+    mem::{self},
-    ops::{Deref, DerefMut, IndexMut},
+    ops::{Deref, DerefMut},
 };
 
 pub trait ReadOnlyPE: Deref<Target = [u8]> + Sized + AsRef<[u8]> {
@@ -290,17 +288,24 @@ pub trait MutablePE: ReadOnlyPE + DerefMut<Target = [u8]> + AsMut<[u8]> {
         // 检查一下把，万一调用者没有扩大文件大小
         let sections = self.get_section_headers()?;
         let self_len = self.len();
-        let last_section = sections.last().unwrap();
+        // 需要反向遍历，找到最后一个size_of_raw_data不为0的节区
-        let last_section_end = last_section.pointer_to_raw_data + last_section.size_of_raw_data;
+        // 然后计算这个节区的PointerToRawData+（SizeOfRawData对齐到FileAlignment的值）
+        let mut last_section_end = 0;
+        for section in sections.iter().rev() {
+            if section.size_of_raw_data != 0 {
+                last_section_end = section.pointer_to_raw_data
+                    + self.align_size_with_file_alignment(section.size_of_raw_data)?;
                 if last_section_end as usize + aligned_file_size as usize > self_len {
                     return Err(MutablePEError::CannotExpandFileSize(
                         last_section_end as u32 + aligned_file_size,
                         self_len as u32,
                     ));
                 }
+                break;
+            }
+        }
         let mut nt_header = self.get_nt_header_mut()?;
         let op = nt_header.get_optional_header_mut();
-
         // 更新可选头的SizeOfHeaders和SizeOfImage
         match op {
             ImageOptionalHeaderMut::OptionalHeader32(op) => {
@@ -310,9 +315,7 @@ pub trait MutablePE: ReadOnlyPE + DerefMut<Target = [u8]> + AsMut<[u8]> {
                 op.size_of_headers += aligned_file_size;
             }
         }
-
         let mut_section = self.get_section_headers_mut()?;
-
         let start_offset = mut_section.first().unwrap().pointer_to_raw_data;
         let end_offset = last_section_end;
         // 更新节区头的PointerToRawData
@@ -379,10 +382,8 @@ pub trait MutablePE: ReadOnlyPE + DerefMut<Target = [u8]> + AsMut<[u8]> {
         }
         new_section.virtual_size = section_alignment;
         // 如果section_size是0，那么virtual_size必须得是最小的section_alignment
-
         // 新节区的virtual_address是上一个节区的virtual_address+(pointer_to_raw_data 对齐到 section_alignment的值)
         let last_section = self.get_section_headers()?.last().unwrap();
-        // TODO: VA计算有问题
         let mut last_section_size_of_raw_data_aligned =
             self.align_size_with_section_alignment(last_section.size_of_raw_data)?;
         if last_section_size_of_raw_data_aligned == 0 {
@@ -390,19 +391,24 @@ pub trait MutablePE: ReadOnlyPE + DerefMut<Target = [u8]> + AsMut<[u8]> {
         }
         new_section.virtual_address =
             last_section.virtual_address + last_section_size_of_raw_data_aligned;
-        // 新节区的size_of_raw_data是section_size对齐到file_alignment的值
-        // 如果section_size是0，那么size_of_raw_data也是0
         new_section.size_of_raw_data = file_alignment;
-        // 新节区的pointer_to_raw_data是上一个节区的pointer_to_raw_data+上一个节区的size_of_raw_data
+        // 如果上一个节区的size_of_raw_data是0，那么上一个节区的pointer_to_raw_data是可以乱写的
-        new_section.pointer_to_raw_data =
+        // 正确的做法应该是，找到上一个size_of_raw_data不为0的节区，然后计算
-            last_section.pointer_to_raw_data + last_section.size_of_raw_data;
+        let sections = self.get_section_headers()?;
+        // 反向遍历
+        for section in sections.iter().rev() {
+            if section.size_of_raw_data != 0 {
+                new_section.pointer_to_raw_data = section.pointer_to_raw_data
+                    + self.align_size_with_file_alignment(section.size_of_raw_data)?;
+                break;
+            }
+        }
         new_section.characteristics = section_characteristics;
         // 其他字段最好填充为0
         new_section.number_of_linenumbers = 0;
         new_section.number_of_relocations = 0;
         new_section.pointer_to_linenumbers = 0;
         new_section.pointer_to_relocations = 0;
-
         // 更新文件头的NumberOfSections
         let file_header = self.get_file_header_mut()?;
         file_header.number_of_sections += 1;