jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <Kernel/Memory/Region.h>
8#include <Kernel/Process.h>
9
10namespace Kernel {
11
12ErrorOr<FlatPtr> Process::sys$get_stack_bounds(Userspace<FlatPtr*> user_stack_base, Userspace<size_t*> user_stack_size)
13{
14 VERIFY_NO_PROCESS_BIG_LOCK(this);
15 auto& regs = Thread::current()->get_register_dump_from_stack();
16 FlatPtr stack_pointer = regs.userspace_sp();
17 return address_space().with([&](auto& space) -> ErrorOr<FlatPtr> {
18 auto* stack_region = space->find_region_containing(Memory::VirtualRange { VirtualAddress(stack_pointer), 1 });
19
20 // The syscall handler should have killed us if we had an invalid stack pointer.
21 VERIFY(stack_region);
22
23 FlatPtr stack_base = stack_region->range().base().get();
24 size_t stack_size = stack_region->size();
25 TRY(copy_to_user(user_stack_base, &stack_base));
26 TRY(copy_to_user(user_stack_size, &stack_size));
27 return 0;
28 });
29}
30
31}