Kernel: Use Userspace<T> for the execve syscall

DevTools/UserspaceEmulator/Emulator.cpp

@@ -957,7 +957,7 @@ int Emulator::virt$execve(FlatPtr params_addr)
     auto copy_string_list = [this](auto& output_vector, auto& string_list) {
         for (size_t i = 0; i < string_list.length; ++i) {
             Syscall::StringArgument string;
-            mmu().copy_from_vm(&string, (FlatPtr)&string_list.strings[i], sizeof(string));
+            mmu().copy_from_vm(&string, (FlatPtr)&string_list.strings.ptr()[i], sizeof(string));
             output_vector.append(String::copy(mmu().copy_buffer_from_vm((FlatPtr)string.characters, string.length)));
         }
     };

Kernel/API/Syscall.h

@@ -241,7 +241,7 @@ struct ImmutableBufferArgument {
 };
 
 struct StringListArgument {
-    StringArgument* strings { nullptr };
+    Userspace<StringArgument*> strings { };
     size_t length { 0 };
 };
 

Kernel/Process.h

@@ -257,7 +257,7 @@ public:
     int sys$ttyname(int fd, Userspace<char*>, size_t);
     int sys$ptsname(int fd, Userspace<char*>, size_t);
     pid_t sys$fork(RegisterState&);
-    int sys$execve(const Syscall::SC_execve_params*);
+    int sys$execve(Userspace<const Syscall::SC_execve_params*>);
     int sys$dup(int oldfd);
     int sys$dup2(int oldfd, int newfd);
     int sys$sigaction(int signum, const sigaction* act, sigaction* old_act);

Kernel/Syscalls/execve.cpp

@@ -544,7 +544,7 @@ int Process::exec(String path, Vector<String> arguments, Vector<String> environm
     return 0;
 }
 
-int Process::sys$execve(const Syscall::SC_execve_params* user_params)
+int Process::sys$execve(Userspace<const Syscall::SC_execve_params*> user_params)
 {
     REQUIRE_PROMISE(exec);
 
@@ -568,14 +568,14 @@ int Process::sys$execve(const Syscall::SC_execve_params* user_params)
         path = path_arg.value();
     }
 
-    auto copy_user_strings = [&](const auto& list, auto& output) {
+    auto copy_user_strings = [this](const auto& list, auto& output) {
         if (!list.length)
             return true;
         if (!validate_read_typed(list.strings, list.length))
             return false;
         Vector<Syscall::StringArgument, 32> strings;
         strings.resize(list.length);
-        copy_from_user(strings.data(), list.strings, list.length * sizeof(Syscall::StringArgument));
+        copy_from_user(strings.data(), list.strings.unsafe_userspace_ptr(), list.length * sizeof(Syscall::StringArgument));
         for (size_t i = 0; i < list.length; ++i) {
             auto string = validate_and_copy_string_from_user(strings[i]);
             if (string.is_null())

Libraries/LibC/unistd.cpp

@@ -94,8 +94,8 @@ int execve(const char* filename, char* const argv[], char* const envp[])
     auto copy_strings = [&](auto& vec, size_t count, auto& output) {
         output.length = count;
         for (size_t i = 0; vec[i]; ++i) {
-            output.strings[i].characters = vec[i];
-            output.strings[i].length = strlen(vec[i]);
+            output.strings.ptr()[i].characters = vec[i];
+            output.strings.ptr()[i].length = strlen(vec[i]);
         }
     };