From e93e41ce83da1c0034442db163feb1efad0f4fd9 Mon Sep 17 00:00:00 2001
From: "qcqcqc@wsl" <1220204124@zust.edu.cn>
Date: Wed, 16 Apr 2025 11:28:18 +0800
Subject: [PATCH] =?UTF-8?q?execve=E5=9C=A8hook=E6=A8=A1=E5=BC=8F=E8=87=AA?=
 =?UTF-8?q?=E5=8A=A8=E7=A7=BB=E9=99=A4LD=5FPRELOAD=E7=8E=AF=E5=A2=83?=
 =?UTF-8?q?=E5=8F=98=E9=87=8F=EF=BC=8C=E9=98=B2=E6=AD=A2=E5=90=91=E4=B8=8B?=
 =?UTF-8?q?=E4=BC=A0=E9=80=92?=
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---
 src/execve_interceptor.c | 57 ++++++++++++++++++++--------------------
 1 file changed, 29 insertions(+), 28 deletions(-)

diff --git a/src/execve_interceptor.c b/src/execve_interceptor.c
index 59f88d9..d3f6c20 100644
--- a/src/execve_interceptor.c
+++ b/src/execve_interceptor.c
@@ -25,7 +25,33 @@ orig_execve_type orig_execve = NULL;
  * 拦截系统调用execve,
  * 在真实调用直接检查配置和创建输出
  */
-int execve(const char *filename, char *const argv[], char *const envp[]) {
+int execve(const char *filename, char *const argv[], char *const old_envp[]) {
+    // 移除LD_PRELOAD
+
+    // 计算原环境变量数量
+    size_t env_count = 0;
+    while (old_envp && old_envp[env_count]) {
+        env_count++;
+    }
+
+    // 分配新的环境变量数组（最多比原来少一个）
+    char **envp = malloc((env_count) * sizeof(char *));
+    if (!envp) {
+        perror("malloc");
+        return -1;
+    }
+
+    // 拷贝旧的 envp，跳过 LD_PRELOAD
+    size_t i = 0;
+    for (size_t j = 0; j < env_count; j++) {
+        if (strncmp(old_envp[j], "LD_PRELOAD=", 11) != 0) {
+            envp[i++] = old_envp[j];
+        }
+    }
+
+    // 确保新数组末尾是 NULL
+    envp[i] = NULL;
+
 #else
 /**
  * 在真实系统调用之前可以调用这个函数，
@@ -37,6 +63,7 @@ int enhance_execve(const char *filename, char *const argv[],
                    char *const envp[]) {
     (void)envp;
 #endif
+
     // 去除首尾空格
     while (*filename && isspace(*filename)) {
         filename++;
@@ -196,33 +223,7 @@ int enhance_execve(const char *filename, char *const argv[],
 
 #ifdef HOOK
 
-    // 移除LD_PRELOAD
-
-    // 计算原环境变量数量
-    size_t env_count = 0;
-    while (envp && envp[env_count]) {
-        env_count++;
-    }
-
-    // 分配新的环境变量数组（最多比原来少一个）
-    char **new_envp = malloc((env_count) * sizeof(char *));
-    if (!new_envp) {
-        perror("malloc");
-        return -1;
-    }
-
-    // 拷贝旧的 envp，跳过 LD_PRELOAD
-    size_t i = 0;
-    for (size_t j = 0; j < env_count; j++) {
-        if (strncmp(envp[j], "LD_PRELOAD=", 11) != 0) {
-            new_envp[i++] = envp[j];
-        }
-    }
-
-    // 确保新数组末尾是 NULL
-    new_envp[i] = NULL;
-
-    return orig_execve(filename, argv, new_envp);
+    return orig_execve(filename, argv, envp);
 #else
     DEBUG_LOG("Ready to exec file: %s", filename);
     return execve(filename, argv, envp);