ladybird/Kernel/Syscalls/open.cpp
Idan Horowitz 9547a8e8a2 Kernel: Remove big lock from sys$close
This syscall doesn't access any unprotected shared data.
2022-04-09 23:46:02 +02:00

83 lines
2.4 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Debug.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Net/LocalSocket.h>
#include <Kernel/Process.h>
namespace Kernel {
ErrorOr<FlatPtr> Process::sys$open(Userspace<Syscall::SC_open_params const*> user_params)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
auto params = TRY(copy_typed_from_user(user_params));
int dirfd = params.dirfd;
int options = params.options;
u16 mode = params.mode;
if (options & O_NOFOLLOW_NOERROR)
return EINVAL;
if (options & O_UNLINK_INTERNAL)
return EINVAL;
if (options & O_WRONLY)
TRY(require_promise(Pledge::wpath));
else if (options & O_RDONLY)
TRY(require_promise(Pledge::rpath));
if (options & O_CREAT)
TRY(require_promise(Pledge::cpath));
// Ignore everything except permission bits.
mode &= 0777;
auto path = TRY(get_syscall_path_argument(params.path));
dbgln_if(IO_DEBUG, "sys$open(dirfd={}, path='{}', options={}, mode={})", dirfd, path->view(), options, mode);
auto fd_allocation = TRY(allocate_fd());
RefPtr<Custody> base;
if (dirfd == AT_FDCWD) {
base = current_directory();
} else {
auto base_description = TRY(open_file_description(dirfd));
if (!base_description->is_directory())
return ENOTDIR;
if (!base_description->custody())
return EINVAL;
base = base_description->custody();
}
auto description = TRY(VirtualFileSystem::the().open(path->view(), options, mode & ~umask(), *base));
if (description->inode() && description->inode()->bound_socket())
return ENXIO;
return m_fds.with_exclusive([&](auto& fds) -> ErrorOr<FlatPtr> {
u32 fd_flags = (options & O_CLOEXEC) ? FD_CLOEXEC : 0;
fds[fd_allocation.fd].set(move(description), fd_flags);
return fd_allocation.fd;
});
}
ErrorOr<FlatPtr> Process::sys$close(int fd)
{
VERIFY_NO_PROCESS_BIG_LOCK(this)
TRY(require_promise(Pledge::stdio));
auto description = TRY(open_file_description(fd));
auto result = description->close();
m_fds.with_exclusive([fd](auto& fds) { fds[fd] = {}; });
if (result.is_error())
return result.release_error();
return 0;
}
}