Refactor restart_frontboard_kill to use spawn_and_wait for process termination

Author: jurre111

lara/kexploit/restart_frontboard.c

@@ -1,25 +1,40 @@
 #include "restart_frontboard.h"
 
-#include <stdlib.h>
+
 #include <string.h>
 #include <unistd.h>
 #include <signal.h>
 #include <stdio.h>
+#include <spawn.h>
+#include <sys/wait.h>
+#include <errno.h>
 
 // Simpler implementation for CI/iOS SDK: avoid using libproc APIs
 // which may not be available in the iOS SDK on the build host.
 // Use a best-effort `killall` invocation instead.
 
+static int spawn_and_wait(char *const argv[]) {
+    pid_t pid = 0;
+    int spawn_err = posix_spawnp(&pid, "killall", NULL, NULL, argv, NULL);
+    if (spawn_err != 0) return -1;
+
+    int status = 0;
+    if (waitpid(pid, &status, 0) == -1) return -1;
+
+    if (WIFEXITED(status) && WEXITSTATUS(status) == 0) return 0;
+    return -1;
+}
+
 int restart_frontboard_kill(void) {
-    // Try a graceful terminate first
-    int r = system("killall -s TERM frontboardd 2>/dev/null");
-    if (r == 0) return 0;
+    // Attempt graceful shutdown, then force, then plain invocation.
+    char *const args_term[] = {"killall", "-s", "TERM", "frontboardd", NULL};
+    if (spawn_and_wait(args_term) == 0) return 0;
+
+    char *const args_kill[] = {"killall", "-s", "KILL", "frontboardd", NULL};
+    if (spawn_and_wait(args_kill) == 0) return 0;
 
-    // If graceful termination failed, try force kill
-    r = system("killall -s KILL frontboardd 2>/dev/null");
-    if (r == 0) return 0;
+    char *const args_plain[] = {"killall", "frontboardd", NULL};
+    if (spawn_and_wait(args_plain) == 0) return 0;
 
-    // As a last resort, try plain killall (older busybox-like syntax)
-    r = system("killall frontboardd 2>/dev/null");
-    return (r == 0) ? 0 : -1;
+    return -1;
 }