Fix Crash On ARM Systems

VERSION

@@ -1 +1 @@
-2.1.7
+2.1.8

dependencies/minecraft-pi/CMakeLists.txt

@@ -8,7 +8,6 @@ include(FetchContent)
 FetchContent_Declare(
     minecraft-pi
     URL "${CMAKE_CURRENT_SOURCE_DIR}/minecraft-pi-0.1.1.tar.gz"
-    URL_HASH "SHA256=e0d68918874cdd403de1fd399380ae2930913fcefdbf60a3fbfebb62e2cfacab"
 )
 FetchContent_Populate(minecraft-pi)
 

docs/CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+**2.1.8**
+* Fix Crash On ARM Systems
+
 **2.1.7**
 * Fix On 64-Bit ARM Systems
 

launcher/src/bootstrap.c

@@ -8,6 +8,7 @@
 #include <errno.h>
 #include <sys/stat.h>
 
+#define FORCE_PROC_FOR_ROOT_PATH
 #include <libreborn/libreborn.h>
 
 #include "bootstrap.h"
@@ -129,6 +130,7 @@ void bootstrap(int argc, char *argv[]) {
 
     // Get Binary Directory
     char *binary_directory = get_binary_directory();
+    setenv("MCPI_ROOT_PATH", binary_directory, 1);
 
     // Configure LD_LIBRARY_PATH
     {

launcher/src/client/launcher.cpp

@@ -2,6 +2,7 @@
 #include <cstring>
 #include <cerrno>
 #include <sys/wait.h>
+#include <sys/stat.h>
 #include <vector>
 #include <functional>
 

libreborn/include/libreborn/elf.h

@@ -1,18 +1,25 @@
 #pragma once
 
-#ifdef __arm__
 #include <unistd.h>
 #include <string.h>
 #include <sys/mman.h>
 #include <elf.h>
 
 #include "log.h"
+#include "exec.h"
 
 // Find And Iterate Over All .text Sections In Current Binary
-typedef void (*text_section_callback_t)(void *section, Elf32_Word size, void *data);
+typedef void (*text_section_callback_t)(Elf32_Addr section, Elf32_Word size, void *data);
 static inline void iterate_text_sections(text_section_callback_t callback, void *data) {
+    // Find Main Binary
+    char *real_path = NULL;
+    {
+        char *binary_directory = get_binary_directory();
+        safe_asprintf(&real_path, "%s/minecraft-pi", binary_directory);
+        free(binary_directory);
+    }
+
     // Load Main Binary
-    char *real_path = realpath("/proc/self/exe", NULL);
     FILE *file_obj = fopen(real_path, "rb");
 
     // Verify Binary
@@ -47,7 +54,7 @@ static inline void iterate_text_sections(text_section_callback_t callback, void
         // Check Section Type
         if (strcmp(name, ".text") == 0) {
             // .text Section
-            (*callback)((void *) header.sh_addr, header.sh_size, data);
+            (*callback)(header.sh_addr, header.sh_size, data);
             text_sections++;
         }
     }
@@ -64,4 +71,3 @@ static inline void iterate_text_sections(text_section_callback_t callback, void
     munmap(file_map, size);
     fclose(file_obj);
 }
-#endif // #ifdef __arm__

libreborn/include/libreborn/exec.h

@@ -3,8 +3,6 @@
 #include <unistd.h>
 #include <stdint.h>
 #include <errno.h>
-#include <sys/stat.h>
-#include <limits.h>
 #include <string.h>
 
 #include "log.h"
@@ -24,30 +22,23 @@ __attribute__((noreturn)) static inline void safe_execvpe(const char *pathname,
 // Get Binary Directory (Remember To Free)
 #define EXE_PATH "/proc/self/exe"
 static inline char *get_binary_directory() {
+#ifndef FORCE_PROC_FOR_ROOT_PATH
+    {
+        // Check Environment
+        char *specified_root = getenv("MCPI_ROOT_PATH");
+        if (specified_root != NULL) {
+            return strdup(specified_root);
+        }
+    }
+#endif
+
     // Get Path To Current Executable
-    // Get Symlink Path Size
+    char *exe = realpath("/proc/self/exe", NULL);
-    struct stat sb;
-    if (lstat(EXE_PATH, &sb) == -1) {
-        ERR("Unable To Get " EXE_PATH " Symlink Size: %s", strerror(errno));
-    }
-    ssize_t path_size = sb.st_size;
-    if (sb.st_size <= 0) {
-        path_size = PATH_MAX;
-    }
-    char *exe = (char *) malloc(path_size + 1);
     ALLOC_CHECK(exe);
-    // Read Link
-    ssize_t r = readlink(EXE_PATH, exe, path_size);
-    if (r < 0) {
-        ERR("Unable To Read " EXE_PATH " Symlink: %s", strerror(errno));
-    }
-    if (r > path_size) {
-        ERR("%s", "Size Of Symlink " EXE_PATH " Changed");
-    }
-    exe[r + 1] = '\0';
 
     // Chop Off Last Component
-    for (int i = r; i >= 0; i--) {
+    int length = strlen(exe);
+    for (int i = length - 1; i >= 0; i--) {
         if (exe[i] == '/') {
             exe[i] = '\0';
             break;

libreborn/src/libreborn.c

@@ -44,8 +44,9 @@ struct overwrite_data {
     void *replacement;
     int found;
 };
-static void overwrite_calls_callback(void *section, Elf32_Word size, void *data) {
+static void overwrite_calls_callback(Elf32_Addr section_addr, Elf32_Word size, void *data) {
     struct overwrite_data *args = (struct overwrite_data *) data;
+    void *section = (void *) section_addr;
 
     for (uint32_t i = 0; i < size; i = i + 4) {
         unsigned char *addr = ((unsigned char *) section) + i;