9a04f53a0f
It's easy to forget the responsibility of validating and safely copying kernel parameters in code that is far away from syscalls. ioctl's are one such example, and bugs there are just as dangerous as at the root syscall level. To avoid this case, utilize the AK::Userspace<T> template in the ioctl kernel interface so that implementors have no choice but to properly validate and copy ioctl pointer arguments.
139 lines
4.1 KiB
C++
139 lines
4.1 KiB
C++
/*
|
|
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <AK/StringView.h>
|
|
#include <Kernel/FileSystem/FileDescription.h>
|
|
#include <Kernel/FileSystem/Inode.h>
|
|
#include <Kernel/FileSystem/InodeFile.h>
|
|
#include <Kernel/FileSystem/VirtualFileSystem.h>
|
|
#include <Kernel/Process.h>
|
|
#include <Kernel/VM/PrivateInodeVMObject.h>
|
|
#include <Kernel/VM/SharedInodeVMObject.h>
|
|
#include <LibC/errno_numbers.h>
|
|
#include <LibC/sys/ioctl_numbers.h>
|
|
|
|
namespace Kernel {
|
|
|
|
InodeFile::InodeFile(NonnullRefPtr<Inode>&& inode)
|
|
: m_inode(move(inode))
|
|
{
|
|
}
|
|
|
|
InodeFile::~InodeFile()
|
|
{
|
|
}
|
|
|
|
KResultOr<size_t> InodeFile::read(FileDescription& description, u64 offset, UserOrKernelBuffer& buffer, size_t count)
|
|
{
|
|
if (Checked<off_t>::addition_would_overflow(offset, count))
|
|
return EOVERFLOW;
|
|
|
|
auto result = m_inode->read_bytes(offset, count, buffer, &description);
|
|
if (result.is_error())
|
|
return result.error();
|
|
auto nread = result.value();
|
|
if (nread > 0) {
|
|
Thread::current()->did_file_read(nread);
|
|
evaluate_block_conditions();
|
|
}
|
|
return nread;
|
|
}
|
|
|
|
KResultOr<size_t> InodeFile::write(FileDescription& description, u64 offset, const UserOrKernelBuffer& data, size_t count)
|
|
{
|
|
if (Checked<off_t>::addition_would_overflow(offset, count))
|
|
return EOVERFLOW;
|
|
|
|
auto result = m_inode->write_bytes(offset, count, data, &description);
|
|
if (result.is_error())
|
|
return result.error();
|
|
|
|
auto nwritten = result.value();
|
|
if (nwritten > 0) {
|
|
auto mtime_result = m_inode->set_mtime(kgettimeofday().to_truncated_seconds());
|
|
Thread::current()->did_file_write(nwritten);
|
|
evaluate_block_conditions();
|
|
if (mtime_result.is_error())
|
|
return mtime_result;
|
|
}
|
|
return nwritten;
|
|
}
|
|
|
|
int InodeFile::ioctl(FileDescription& description, unsigned request, Userspace<void*> arg)
|
|
{
|
|
(void)description;
|
|
|
|
switch (request) {
|
|
case FIBMAP: {
|
|
if (!Process::current()->is_superuser())
|
|
return -EPERM;
|
|
|
|
auto user_block_number = static_ptr_cast<int*>(arg);
|
|
int block_number = 0;
|
|
if (!copy_from_user(&block_number, user_block_number))
|
|
return -EFAULT;
|
|
|
|
if (block_number < 0)
|
|
return -EINVAL;
|
|
|
|
auto block_address = inode().get_block_address(block_number);
|
|
if (block_address.is_error())
|
|
return block_address.error();
|
|
|
|
if (!copy_to_user(user_block_number, &block_address.value()))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
KResultOr<Region*> InodeFile::mmap(Process& process, FileDescription& description, const Range& range, u64 offset, int prot, bool shared)
|
|
{
|
|
// FIXME: If PROT_EXEC, check that the underlying file system isn't mounted noexec.
|
|
RefPtr<InodeVMObject> vmobject;
|
|
if (shared)
|
|
vmobject = SharedInodeVMObject::try_create_with_inode(inode());
|
|
else
|
|
vmobject = PrivateInodeVMObject::try_create_with_inode(inode());
|
|
if (!vmobject)
|
|
return ENOMEM;
|
|
return process.space().allocate_region_with_vmobject(range, vmobject.release_nonnull(), offset, description.absolute_path(), prot, shared);
|
|
}
|
|
|
|
String InodeFile::absolute_path(const FileDescription& description) const
|
|
{
|
|
VERIFY_NOT_REACHED();
|
|
VERIFY(description.custody());
|
|
return description.absolute_path();
|
|
}
|
|
|
|
KResult InodeFile::truncate(u64 size)
|
|
{
|
|
if (auto result = m_inode->truncate(size); result.is_error())
|
|
return result;
|
|
if (auto result = m_inode->set_mtime(kgettimeofday().to_truncated_seconds()); result.is_error())
|
|
return result;
|
|
return KSuccess;
|
|
}
|
|
|
|
KResult InodeFile::chown(FileDescription& description, uid_t uid, gid_t gid)
|
|
{
|
|
VERIFY(description.inode() == m_inode);
|
|
VERIFY(description.custody());
|
|
return VirtualFileSystem::the().chown(*description.custody(), uid, gid);
|
|
}
|
|
|
|
KResult InodeFile::chmod(FileDescription& description, mode_t mode)
|
|
{
|
|
VERIFY(description.inode() == m_inode);
|
|
VERIFY(description.custody());
|
|
return VirtualFileSystem::the().chmod(*description.custody(), mode);
|
|
}
|
|
|
|
}
|