ladybird/Kernel/Syscalls/inode_watcher.cpp
Andreas Kling c3351d4b9f Kernel: Make VirtualFileSystem functions take credentials as input
Instead of getting credentials from Process::current(), we now require
that they be provided as input to the various VFS functions.

This ensures that an atomic set of credentials is used throughout an
entire VFS operation.
2022-08-21 16:02:24 +02:00

68 lines
2.3 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/API/InodeWatcherFlags.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/InodeWatcher.h>
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Process.h>
namespace Kernel {
ErrorOr<FlatPtr> Process::sys$create_inode_watcher(u32 flags)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
TRY(require_promise(Pledge::rpath));
auto fd_allocation = TRY(allocate_fd());
auto watcher = TRY(InodeWatcher::try_create());
auto description = TRY(OpenFileDescription::try_create(move(watcher)));
description->set_readable(true);
if (flags & static_cast<unsigned>(InodeWatcherFlags::Nonblock))
description->set_blocking(false);
return m_fds.with_exclusive([&](auto& fds) -> ErrorOr<FlatPtr> {
fds[fd_allocation.fd].set(move(description));
if (flags & static_cast<unsigned>(InodeWatcherFlags::CloseOnExec))
fds[fd_allocation.fd].set_flags(fds[fd_allocation.fd].flags() | FD_CLOEXEC);
return fd_allocation.fd;
});
}
ErrorOr<FlatPtr> Process::sys$inode_watcher_add_watch(Userspace<Syscall::SC_inode_watcher_add_watch_params const*> user_params)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
TRY(require_promise(Pledge::rpath));
auto params = TRY(copy_typed_from_user(user_params));
auto description = TRY(open_file_description(params.fd));
if (!description->is_inode_watcher())
return EBADF;
auto* inode_watcher = description->inode_watcher();
auto path = TRY(get_syscall_path_argument(params.user_path));
auto custody = TRY(VirtualFileSystem::the().resolve_path(credentials(), path->view(), current_directory()));
if (!custody->inode().fs().supports_watchers())
return ENOTSUP;
return TRY(inode_watcher->register_inode(custody->inode(), params.event_mask));
}
ErrorOr<FlatPtr> Process::sys$inode_watcher_remove_watch(int fd, int wd)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
auto description = TRY(open_file_description(fd));
if (!description->is_inode_watcher())
return EBADF;
TRY(description->inode_watcher()->unregister_by_wd(wd));
return 0;
}
}