ladybird/Kernel/Syscalls/realpath.cpp
Brian Gianforcaro 9201a06027 Kernel: Annotate all syscalls with VERIFY_PROCESS_BIG_LOCK_ACQUIRED
Before we start disabling acquisition of the big process lock for
specific syscalls, make sure to document and assert that all the
lock is held during all syscalls.
2021-07-20 03:21:14 +02:00

43 lines
1.3 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/StringView.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Process.h>
namespace Kernel {
KResultOr<FlatPtr> Process::sys$realpath(Userspace<const Syscall::SC_realpath_params*> user_params)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(rpath);
Syscall::SC_realpath_params params;
if (!copy_from_user(&params, user_params))
return EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
auto custody_or_error = VirtualFileSystem::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();
auto absolute_path = custody->try_create_absolute_path();
if (!absolute_path)
return ENOMEM;
size_t ideal_size = absolute_path->length() + 1;
auto size_to_copy = min(ideal_size, params.buffer.size);
if (!copy_to_user(params.buffer.data, absolute_path->characters(), size_to_copy))
return EFAULT;
// Note: we return the whole size here, not the copied size.
return ideal_size;
};
}