Kernel: Convert Process::get_syscall_path_argument() to KString

This API now returns a KResultOr<NonnullOwnPtr<KString>> and allocation
failures should be propagated everywhere nicely. :^)

Kernel/Process.cpp

@@ -434,19 +434,19 @@ Custody& Process::current_directory()
     return *m_cwd;
 }
 
-KResultOr<String> Process::get_syscall_path_argument(const char* user_path, size_t path_length) const
+KResultOr<NonnullOwnPtr<KString>> Process::get_syscall_path_argument(char const* user_path, size_t path_length) const
 {
     if (path_length == 0)
         return EINVAL;
     if (path_length > PATH_MAX)
         return ENAMETOOLONG;
-    auto copied_string = copy_string_from_user(user_path, path_length);
-    if (copied_string.is_null())
-        return EFAULT;
-    return copied_string;
+    auto string_or_error = try_copy_kstring_from_user(user_path, path_length);
+    if (string_or_error.is_error())
+        return string_or_error.error();
+    return string_or_error.release_value();
 }
 
-KResultOr<String> Process::get_syscall_path_argument(const Syscall::StringArgument& path) const
+KResultOr<NonnullOwnPtr<KString>> Process::get_syscall_path_argument(Syscall::StringArgument const& path) const
 {
     return get_syscall_path_argument(path.characters, path.length);
 }

Kernel/Process.h

@@ -546,12 +546,12 @@ private:
 
     KResultOr<siginfo_t> do_waitid(idtype_t idtype, int id, int options);
 
-    KResultOr<String> get_syscall_path_argument(const char* user_path, size_t path_length) const;
-    KResultOr<String> get_syscall_path_argument(Userspace<const char*> user_path, size_t path_length) const
+    KResultOr<NonnullOwnPtr<KString>> get_syscall_path_argument(const char* user_path, size_t path_length) const;
+    KResultOr<NonnullOwnPtr<KString>> get_syscall_path_argument(Userspace<const char*> user_path, size_t path_length) const
     {
         return get_syscall_path_argument(user_path.unsafe_userspace_ptr(), path_length);
     }
-    KResultOr<String> get_syscall_path_argument(const Syscall::StringArgument&) const;
+    KResultOr<NonnullOwnPtr<KString>> get_syscall_path_argument(const Syscall::StringArgument&) const;
 
     bool has_tracee_thread(ProcessID tracer_pid);
 

Kernel/Syscalls/access.cpp

@@ -16,7 +16,7 @@ KResultOr<int> Process::sys$access(Userspace<const char*> user_path, size_t path
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    return VFS::the().access(path.value(), mode, current_directory());
+    return VFS::the().access(path.value()->view(), mode, current_directory());
 }
 
 }

Kernel/Syscalls/chdir.cpp

@@ -17,7 +17,7 @@ KResultOr<int> Process::sys$chdir(Userspace<const char*> user_path, size_t path_
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    auto directory_or_error = VFS::the().open_directory(path.value(), current_directory());
+    auto directory_or_error = VFS::the().open_directory(path.value()->view(), current_directory());
     if (directory_or_error.is_error())
         return directory_or_error.error();
     m_cwd = *directory_or_error.value();

Kernel/Syscalls/chmod.cpp

@@ -17,7 +17,7 @@ KResultOr<int> Process::sys$chmod(Userspace<const char*> user_path, size_t path_
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    return VFS::the().chmod(path.value(), mode, current_directory());
+    return VFS::the().chmod(path.value()->view(), mode, current_directory());
 }
 
 KResultOr<int> Process::sys$fchmod(int fd, mode_t mode)

Kernel/Syscalls/chown.cpp

@@ -27,7 +27,7 @@ KResultOr<int> Process::sys$chown(Userspace<const Syscall::SC_chown_params*> use
     auto path = get_syscall_path_argument(params.path);
     if (path.is_error())
         return path.error();
-    return VFS::the().chown(path.value(), params.uid, params.gid, current_directory());
+    return VFS::the().chown(path.value()->view(), params.uid, params.gid, current_directory());
 }
 
 }

Kernel/Syscalls/chroot.cpp

@@ -19,7 +19,7 @@ KResultOr<int> Process::sys$chroot(Userspace<const char*> user_path, size_t path
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    auto directory_or_error = VFS::the().open_directory(path.value(), current_directory());
+    auto directory_or_error = VFS::the().open_directory(path.value()->view(), current_directory());
     if (directory_or_error.is_error())
         return directory_or_error.error();
     auto directory = directory_or_error.value();

Kernel/Syscalls/execve.cpp

@@ -920,7 +920,7 @@ KResultOr<int> Process::sys$execve(Userspace<const Syscall::SC_execve_params*> u
         auto path_arg = get_syscall_path_argument(params.path);
         if (path_arg.is_error())
             return path_arg.error();
-        path = path_arg.value();
+        path = path_arg.value()->view();
     }
 
     auto copy_user_strings = [](const auto& list, auto& output) {

Kernel/Syscalls/inode_watcher.cpp

@@ -59,7 +59,7 @@ KResultOr<int> Process::sys$inode_watcher_add_watch(Userspace<const Syscall::SC_
     if (path.is_error())
         return path.error();
 
-    auto custody_or_error = VFS::the().resolve_path(path.value(), current_directory());
+    auto custody_or_error = VFS::the().resolve_path(path.value()->view(), current_directory());
     if (custody_or_error.is_error())
         return custody_or_error.error();
 

Kernel/Syscalls/keymap.cpp

@@ -36,13 +36,12 @@ KResultOr<int> Process::sys$setkeymap(Userspace<const Syscall::SC_setkeymap_para
         return EFAULT;
 
     auto map_name = get_syscall_path_argument(params.map_name);
-    if (map_name.is_error()) {
+    if (map_name.is_error())
         return map_name.error();
-    }
-    if (map_name.value().length() > map_name_max_size) {
+    if (map_name.value()->length() > map_name_max_size)
         return ENAMETOOLONG;
-    }
-    HIDManagement::the().set_maps(character_map_data, map_name.value());
+
+    HIDManagement::the().set_maps(character_map_data, map_name.value()->view());
     return 0;
 }
 

Kernel/Syscalls/link.cpp

@@ -37,7 +37,7 @@ KResultOr<int> Process::sys$symlink(Userspace<const Syscall::SC_symlink_params*>
     auto linkpath = get_syscall_path_argument(params.linkpath);
     if (linkpath.is_error())
         return linkpath.error();
-    return VFS::the().symlink(target.value(), linkpath.value(), current_directory());
+    return VFS::the().symlink(target.value()->view(), linkpath.value()->view(), current_directory());
 }
 
 }

Kernel/Syscalls/mkdir.cpp

@@ -16,6 +16,6 @@ KResultOr<int> Process::sys$mkdir(Userspace<const char*> user_path, size_t path_
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    return VFS::the().mkdir(path.value(), mode & ~umask(), current_directory());
+    return VFS::the().mkdir(path.value()->view(), mode & ~umask(), current_directory());
 }
 }

Kernel/Syscalls/mknod.cpp

@@ -21,7 +21,7 @@ KResultOr<int> Process::sys$mknod(Userspace<const Syscall::SC_mknod_params*> use
     auto path = get_syscall_path_argument(params.path);
     if (path.is_error())
         return path.error();
-    return VFS::the().mknod(path.value(), params.mode & ~umask(), params.dev, current_directory());
+    return VFS::the().mknod(path.value()->view(), params.mode & ~umask(), params.dev, current_directory());
 }
 
 }

Kernel/Syscalls/module.cpp

@@ -25,7 +25,7 @@ KResultOr<int> Process::sys$module_load(Userspace<const char*> user_path, size_t
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    auto description_or_error = VFS::the().open(path.value(), O_RDONLY, 0, current_directory());
+    auto description_or_error = VFS::the().open(path.value()->view(), O_RDONLY, 0, current_directory());
     if (description_or_error.is_error())
         return description_or_error.error();
     auto& description = description_or_error.value();

Kernel/Syscalls/mount.cpp

@@ -119,7 +119,7 @@ KResultOr<int> Process::sys$umount(Userspace<const char*> user_mountpoint, size_
     if (mountpoint.is_error())
         return mountpoint.error();
 
-    auto custody_or_error = VFS::the().resolve_path(mountpoint.value(), current_directory());
+    auto custody_or_error = VFS::the().resolve_path(mountpoint.value()->view(), current_directory());
     if (custody_or_error.is_error())
         return custody_or_error.error();
 

Kernel/Syscalls/open.cpp

@@ -43,7 +43,7 @@ KResultOr<int> Process::sys$open(Userspace<const Syscall::SC_open_params*> user_
     if (path.is_error())
         return path.error();
 
-    dbgln_if(IO_DEBUG, "sys$open(dirfd={}, path='{}', options={}, mode={})", dirfd, path.value(), options, mode);
+    dbgln_if(IO_DEBUG, "sys$open(dirfd={}, path='{}', options={}, mode={})", dirfd, path.value()->view(), options, mode);
     int fd = alloc_fd();
     if (fd < 0)
         return fd;
@@ -62,7 +62,7 @@ KResultOr<int> Process::sys$open(Userspace<const Syscall::SC_open_params*> user_
         base = base_description->custody();
     }
 
-    auto result = VFS::the().open(path.value(), options, mode & ~umask(), *base);
+    auto result = VFS::the().open(path.value()->view(), options, mode & ~umask(), *base);
     if (result.is_error())
         return result.error();
     auto description = result.value();

Kernel/Syscalls/readlink.cpp

@@ -23,7 +23,7 @@ KResultOr<int> Process::sys$readlink(Userspace<const Syscall::SC_readlink_params
     if (path.is_error())
         return path.error();
 
-    auto result = VFS::the().open(path.value(), O_RDONLY | O_NOFOLLOW_NOERROR, 0, current_directory());
+    auto result = VFS::the().open(path.value()->view(), O_RDONLY | O_NOFOLLOW_NOERROR, 0, current_directory());
     if (result.is_error())
         return result.error();
     auto description = result.value();

Kernel/Syscalls/realpath.cpp

@@ -23,7 +23,7 @@ KResultOr<int> Process::sys$realpath(Userspace<const Syscall::SC_realpath_params
     if (path.is_error())
         return path.error();
 
-    auto custody_or_error = VFS::the().resolve_path(path.value(), current_directory());
+    auto custody_or_error = VFS::the().resolve_path(path.value()->view(), current_directory());
     if (custody_or_error.is_error())
         return custody_or_error.error();
     auto& custody = custody_or_error.value();

Kernel/Syscalls/rename.cpp

@@ -22,7 +22,7 @@ KResultOr<int> Process::sys$rename(Userspace<const Syscall::SC_rename_params*> u
     auto new_path = get_syscall_path_argument(params.new_path);
     if (new_path.is_error())
         return new_path.error();
-    return VFS::the().rename(old_path.value(), new_path.value(), current_directory());
+    return VFS::the().rename(old_path.value()->view(), new_path.value()->view(), current_directory());
 }
 
 }

Kernel/Syscalls/rmdir.cpp

@@ -16,7 +16,7 @@ KResultOr<int> Process::sys$rmdir(Userspace<const char*> user_path, size_t path_
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    return VFS::the().rmdir(path.value(), current_directory());
+    return VFS::the().rmdir(path.value()->view(), current_directory());
 }
 
 }

Kernel/Syscalls/stat.cpp

@@ -47,7 +47,7 @@ KResultOr<int> Process::sys$stat(Userspace<const Syscall::SC_stat_params*> user_
             return EINVAL;
         base = base_description->custody();
     }
-    auto metadata_or_error = VFS::the().lookup_metadata(path.value(), *base, params.follow_symlinks ? 0 : O_NOFOLLOW_NOERROR);
+    auto metadata_or_error = VFS::the().lookup_metadata(path.value()->view(), *base, params.follow_symlinks ? 0 : O_NOFOLLOW_NOERROR);
     if (metadata_or_error.is_error())
         return metadata_or_error.error();
     stat statbuf;

Kernel/Syscalls/statvfs.cpp

@@ -80,7 +80,7 @@ KResultOr<int> Process::sys$statvfs(Userspace<const Syscall::SC_statvfs_params*>
     if (path.is_error())
         return path.error();
 
-    return do_statvfs(path.value(), params.buf);
+    return do_statvfs(path.value()->view(), params.buf);
 }
 
 KResultOr<int> Process::sys$fstatvfs(int fd, statvfs* buf)

Kernel/Syscalls/unlink.cpp

@@ -16,7 +16,7 @@ KResultOr<int> Process::sys$unlink(Userspace<const char*> user_path, size_t path
     auto path = get_syscall_path_argument(user_path, path_length);
     if (path.is_error())
         return path.error();
-    return VFS::the().unlink(path.value(), current_directory());
+    return VFS::the().unlink(path.value()->view(), current_directory());
 }
 
 }

Kernel/Syscalls/unveil.cpp

@@ -32,11 +32,12 @@ KResultOr<int> Process::sys$unveil(Userspace<const Syscall::SC_unveil_params*> u
     if (params.permissions.length > 5)
         return EINVAL;
 
-    auto path = get_syscall_path_argument(params.path);
-    if (path.is_error())
-        return path.error();
+    auto path_or_error = get_syscall_path_argument(params.path);
+    if (path_or_error.is_error())
+        return path_or_error.error();
+    auto& path = *path_or_error.value();
 
-    if (path.value().is_empty() || path.value().characters()[0] != '/')
+    if (path.is_empty() || !path.view().starts_with('/'))
         return EINVAL;
 
     auto permissions = copy_string_from_user(params.permissions);
@@ -74,11 +75,11 @@ KResultOr<int> Process::sys$unveil(Userspace<const Syscall::SC_unveil_params*> u
     // If this case is encountered, the parent node of the path is returned and the custody of that inode is used instead.
     RefPtr<Custody> parent_custody; // Parent inode in case of ENOENT
     String new_unveiled_path;
-    auto custody_or_error = VFS::the().resolve_path_without_veil(path.value(), root_directory(), &parent_custody);
+    auto custody_or_error = VFS::the().resolve_path_without_veil(path.view(), root_directory(), &parent_custody);
     if (!custody_or_error.is_error()) {
         new_unveiled_path = custody_or_error.value()->absolute_path();
     } else if (custody_or_error.error() == -ENOENT && parent_custody && (new_permissions & UnveilAccess::CreateOrRemove)) {
-        String basename = LexicalPath(path.value()).basename();
+        String basename = LexicalPath(path.view()).basename();
         new_unveiled_path = String::formatted("{}/{}", parent_custody->absolute_path(), basename);
     } else {
         // FIXME Should this be EINVAL?

Kernel/Syscalls/utime.cpp

@@ -25,7 +25,7 @@ KResultOr<int> Process::sys$utime(Userspace<const char*> user_path, size_t path_
         // Not a bug!
         buf = { now, now };
     }
-    return VFS::the().utime(path.value(), current_directory(), buf.actime, buf.modtime);
+    return VFS::the().utime(path.value()->view(), current_directory(), buf.actime, buf.modtime);
 }
 
 }