/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Demangle.h>
#include <AK/FileSystemPath.h>
#include <AK/ScopeGuard.h>
#include <AK/StdLibExtras.h>
#include <AK/StringBuilder.h>
#include <AK/Time.h>
#include <AK/Types.h>
#include <Kernel/ACPI/ACPIParser.h>
#include <Kernel/Arch/i386/CPU.h>
#include <Kernel/Devices/BlockDevice.h>
#include <Kernel/Devices/KeyboardDevice.h>
#include <Kernel/Devices/NullDevice.h>
#include <Kernel/Devices/PCSpeaker.h>
#include <Kernel/Devices/RandomDevice.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/DevPtsFS.h>
#include <Kernel/FileSystem/Ext2FileSystem.h>
#include <Kernel/FileSystem/FIFO.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/FileSystem/InodeWatcher.h>
#include <Kernel/FileSystem/ProcFS.h>
#include <Kernel/FileSystem/TmpFS.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Heap/kmalloc.h>
#include <Kernel/KBufferBuilder.h>
#include <Kernel/KSyms.h>
#include <Kernel/KernelInfoPage.h>
#include <Kernel/Module.h>
#include <Kernel/Multiboot.h>
#include <Kernel/Net/Socket.h>
#include <Kernel/PerformanceEventBuffer.h>
#include <Kernel/Process.h>
#include <Kernel/ProcessTracer.h>
#include <Kernel/Profiling.h>
#include <Kernel/RTC.h>
#include <Kernel/Random.h>
#include <Kernel/Scheduler.h>
#include <Kernel/SharedBuffer.h>
#include <Kernel/Syscall.h>
#include <Kernel/TTY/MasterPTY.h>
#include <Kernel/TTY/TTY.h>
#include <Kernel/Thread.h>
#include <Kernel/Time/TimeManagement.h>
#include <Kernel/VM/PageDirectory.h>
#include <Kernel/VM/PrivateInodeVMObject.h>
#include <Kernel/VM/PurgeableVMObject.h>
#include <Kernel/VM/SharedInodeVMObject.h>
#include <LibBareMetal/IO.h>
#include <LibBareMetal/Output/Console.h>
#include <LibBareMetal/StdLib.h>
#include <LibC/errno_numbers.h>
#include <LibC/limits.h>
#include <LibC/signal_numbers.h>
#include <LibELF/ELFLoader.h>
//#define PROCESS_DEBUG
//#define DEBUG_POLL_SELECT
//#define DEBUG_IO
//#define TASK_DEBUG
//#define FORK_DEBUG
//#define EXEC_DEBUG
//#define SIGNAL_DEBUG
//#define SHARED_BUFFER_DEBUG
namespace Kernel {
static void create_signal_trampolines();
static void create_kernel_info_page();
Process* Process::current;
static pid_t next_pid;
InlineLinkedList<Process>* g_processes;
static String* s_hostname;
static Lock* s_hostname_lock;
static VirtualAddress s_info_page_address_for_userspace;
static VirtualAddress s_info_page_address_for_kernel;
VirtualAddress g_return_to_ring3_from_signal_trampoline;
HashMap<String, OwnPtr<Module>>* g_modules;
pid_t Process::allocate_pid()
{
InterruptDisabler disabler;
return next_pid++;
}
void Process::initialize()
{
g_modules = new HashMap<String, OwnPtr<Module>>;
next_pid = 0;
g_processes = new InlineLinkedList<Process>;
s_hostname = new String("courage");
s_hostname_lock = new Lock;
create_signal_trampolines();
create_kernel_info_page();
}
void Process::update_info_page_timestamp(const timeval& tv)
{
auto* info_page = (KernelInfoPage*)s_info_page_address_for_kernel.as_ptr();
info_page->serial++;
const_cast<timeval&>(info_page->now) = tv;
}
Vector<pid_t> Process::all_pids()
{
Vector<pid_t> pids;
InterruptDisabler disabler;
pids.ensure_capacity((int)g_processes->size_slow());
for (auto& process : *g_processes)
pids.append(process.pid());
return pids;
}
Vector<Process*> Process::all_processes()
{
Vector<Process*> processes;
InterruptDisabler disabler;
processes.ensure_capacity((int)g_processes->size_slow());
for (auto& process : *g_processes)
processes.append(&process);
return processes;
}
bool Process::in_group(gid_t gid) const
{
return m_gid == gid || m_extra_gids.contains(gid);
}
Range Process::allocate_range(VirtualAddress vaddr, size_t size, size_t alignment)
{
vaddr.mask(PAGE_MASK);
size = PAGE_ROUND_UP(size);
if (vaddr.is_null())
return page_directory().range_allocator().allocate_anywhere(size, alignment);
return page_directory().range_allocator().allocate_specific(vaddr, size);
}
static unsigned prot_to_region_access_flags(int prot)
{
unsigned access = 0;
if (prot & PROT_READ)
access |= Region::Access::Read;
if (prot & PROT_WRITE)
access |= Region::Access::Write;
if (prot & PROT_EXEC)
access |= Region::Access::Execute;
return access;
}
Region& Process::allocate_split_region(const Region& source_region, const Range& range, size_t offset_in_vmobject)
{
auto& region = add_region(Region::create_user_accessible(range, source_region.vmobject(), offset_in_vmobject, source_region.name(), source_region.access()));
region.set_mmap(source_region.is_mmap());
region.set_stack(source_region.is_stack());
size_t page_offset_in_source_region = (offset_in_vmobject - source_region.offset_in_vmobject()) / PAGE_SIZE;
for (size_t i = 0; i < region.page_count(); ++i) {
if (source_region.should_cow(page_offset_in_source_region + i))
region.set_should_cow(i, true);
}
return region;
}
Region* Process::allocate_region(const Range& range, const String& name, int prot, bool commit)
{
ASSERT(range.is_valid());
auto vmobject = AnonymousVMObject::create_with_size(range.size());
auto& region = add_region(Region::create_user_accessible(range, vmobject, 0, name, prot_to_region_access_flags(prot)));
region.map(page_directory());
if (commit)
region.commit();
return ®ion;
}
Region* Process::allocate_region(VirtualAddress vaddr, size_t size, const String& name, int prot, bool commit)
{
auto range = allocate_range(vaddr, size);
if (!range.is_valid())
return nullptr;
return allocate_region(range, name, prot, commit);
}
Region* Process::allocate_region_with_vmobject(const Range& range, NonnullRefPtr<VMObject> vmobject, size_t offset_in_vmobject, const String& name, int prot)
{
ASSERT(range.is_valid());
size_t end_in_vmobject = offset_in_vmobject + range.size();
if (end_in_vmobject <= offset_in_vmobject) {
dbg() << "allocate_region_with_vmobject: Overflow (offset + size)";
return nullptr;
}
if (offset_in_vmobject >= vmobject->size()) {
dbg() << "allocate_region_with_vmobject: Attempt to allocate a region with an offset past the end of its VMObject.";
return nullptr;
}
if (end_in_vmobject > vmobject->size()) {
dbg() << "allocate_region_with_vmobject: Attempt to allocate a region with an end past the end of its VMObject.";
return nullptr;
}
offset_in_vmobject &= PAGE_MASK;
auto& region = add_region(Region::create_user_accessible(range, move(vmobject), offset_in_vmobject, name, prot_to_region_access_flags(prot)));
region.map(page_directory());
return ®ion;
}
Region* Process::allocate_region_with_vmobject(VirtualAddress vaddr, size_t size, NonnullRefPtr<VMObject> vmobject, size_t offset_in_vmobject, const String& name, int prot)
{
auto range = allocate_range(vaddr, size);
if (!range.is_valid())
return nullptr;
return allocate_region_with_vmobject(range, move(vmobject), offset_in_vmobject, name, prot);
}
bool Process::deallocate_region(Region& region)
{
InterruptDisabler disabler;
if (m_region_lookup_cache.region == ®ion)
m_region_lookup_cache.region = nullptr;
for (size_t i = 0; i < m_regions.size(); ++i) {
if (&m_regions[i] == ®ion) {
m_regions.unstable_remove(i);
return true;
}
}
return false;
}
Region* Process::region_from_range(const Range& range)
{
if (m_region_lookup_cache.range == range && m_region_lookup_cache.region)
return m_region_lookup_cache.region;
size_t size = PAGE_ROUND_UP(range.size());
for (auto& region : m_regions) {
if (region.vaddr() == range.base() && region.size() == size) {
m_region_lookup_cache.range = range;
m_region_lookup_cache.region = region.make_weak_ptr();
return ®ion;
}
}
return nullptr;
}
Region* Process::region_containing(const Range& range)
{
for (auto& region : m_regions) {
if (region.contains(range))
return ®ion;
}
return nullptr;
}
int Process::sys$set_mmap_name(const Syscall::SC_set_mmap_name_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_set_mmap_name_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (params.name.length > PATH_MAX)
return -ENAMETOOLONG;
auto name = validate_and_copy_string_from_user(params.name);
if (name.is_null())
return -EFAULT;
auto* region = region_from_range({ VirtualAddress(params.addr), params.size });
if (!region)
return -EINVAL;
if (!region->is_mmap())
return -EPERM;
region->set_name(name);
return 0;
}
static bool validate_mmap_prot(int prot, bool map_stack)
{
bool readable = prot & PROT_READ;
bool writable = prot & PROT_WRITE;
bool executable = prot & PROT_EXEC;
if (writable && executable)
return false;
if (map_stack) {
if (executable)
return false;
if (!readable || !writable)
return false;
}
return true;
}
static bool validate_inode_mmap_prot(const Process& process, int prot, const Inode& inode, bool map_shared)
{
auto metadata = inode.metadata();
if ((prot & PROT_READ) && !metadata.may_read(process))
return false;
if (map_shared) {
if ((prot & PROT_WRITE) && !metadata.may_write(process))
return false;
InterruptDisabler disabler;
if (inode.shared_vmobject()) {
if ((prot & PROT_EXEC) && inode.shared_vmobject()->writable_mappings())
return false;
if ((prot & PROT_WRITE) && inode.shared_vmobject()->executable_mappings())
return false;
}
}
return true;
}
// Carve out a virtual address range from a region and return the two regions on either side
Vector<Region*, 2> Process::split_region_around_range(const Region& source_region, const Range& desired_range)
{
Range old_region_range = source_region.range();
auto remaining_ranges_after_unmap = old_region_range.carve(desired_range);
ASSERT(!remaining_ranges_after_unmap.is_empty());
auto make_replacement_region = [&](const Range& new_range) -> Region& {
ASSERT(old_region_range.contains(new_range));
size_t new_range_offset_in_vmobject = source_region.offset_in_vmobject() + (new_range.base().get() - old_region_range.base().get());
return allocate_split_region(source_region, new_range, new_range_offset_in_vmobject);
};
Vector<Region*, 2> new_regions;
for (auto& new_range : remaining_ranges_after_unmap) {
new_regions.unchecked_append(&make_replacement_region(new_range));
}
return new_regions;
}
void* Process::sys$mmap(const Syscall::SC_mmap_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_mmap_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return (void*)-EFAULT;
void* addr = (void*)params.addr;
size_t size = params.size;
size_t alignment = params.alignment;
int prot = params.prot;
int flags = params.flags;
int fd = params.fd;
int offset = params.offset;
if (alignment & ~PAGE_MASK)
return (void*)-EINVAL;
if (!is_user_range(VirtualAddress(addr), size))
return (void*)-EFAULT;
String name;
if (params.name.characters) {
if (params.name.length > PATH_MAX)
return (void*)-ENAMETOOLONG;
name = validate_and_copy_string_from_user(params.name);
if (name.is_null())
return (void*)-EFAULT;
}
if (size == 0)
return (void*)-EINVAL;
if ((FlatPtr)addr & ~PAGE_MASK)
return (void*)-EINVAL;
bool map_shared = flags & MAP_SHARED;
bool map_anonymous = flags & MAP_ANONYMOUS;
bool map_purgeable = flags & MAP_PURGEABLE;
bool map_private = flags & MAP_PRIVATE;
bool map_stack = flags & MAP_STACK;
bool map_fixed = flags & MAP_FIXED;
if (map_shared && map_private)
return (void*)-EINVAL;
if (!map_shared && !map_private)
return (void*)-EINVAL;
if (!validate_mmap_prot(prot, map_stack))
return (void*)-EINVAL;
if (map_stack && (!map_private || !map_anonymous))
return (void*)-EINVAL;
Region* region = nullptr;
auto range = allocate_range(VirtualAddress(addr), size, alignment);
if (!range.is_valid())
return (void*)-ENOMEM;
if (map_purgeable) {
auto vmobject = PurgeableVMObject::create_with_size(size);
region = allocate_region_with_vmobject(range, vmobject, 0, !name.is_null() ? name : "mmap (purgeable)", prot);
if (!region && (!map_fixed && addr != 0))
region = allocate_region_with_vmobject({}, size, vmobject, 0, !name.is_null() ? name : "mmap (purgeable)", prot);
} else if (map_anonymous) {
region = allocate_region(range, !name.is_null() ? name : "mmap", prot, false);
if (!region && (!map_fixed && addr != 0))
region = allocate_region(allocate_range({}, size), !name.is_null() ? name : "mmap", prot, false);
} else {
if (offset < 0)
return (void*)-EINVAL;
if (static_cast<size_t>(offset) & ~PAGE_MASK)
return (void*)-EINVAL;
auto description = file_description(fd);
if (!description)
return (void*)-EBADF;
if (description->is_directory())
return (void*)-ENODEV;
if ((prot & PROT_READ) && !description->is_readable())
return (void*)-EACCES;
if (map_shared) {
if ((prot & PROT_WRITE) && !description->is_writable())
return (void*)-EACCES;
}
if (description->inode()) {
if (!validate_inode_mmap_prot(*this, prot, *description->inode(), map_shared))
return (void*)-EACCES;
}
auto region_or_error = description->mmap(*this, VirtualAddress(addr), static_cast<size_t>(offset), size, prot, map_shared);
if (region_or_error.is_error()) {
// Fail if MAP_FIXED or address is 0, retry otherwise
if (map_fixed || addr == 0)
return (void*)(int)region_or_error.error();
region_or_error = description->mmap(*this, {}, static_cast<size_t>(offset), size, prot, map_shared);
}
if (region_or_error.is_error())
return (void*)(int)region_or_error.error();
region = region_or_error.value();
}
if (!region)
return (void*)-ENOMEM;
region->set_mmap(true);
if (map_shared)
region->set_shared(true);
if (map_stack)
region->set_stack(true);
if (!name.is_null())
region->set_name(name);
return region->vaddr().as_ptr();
}
int Process::sys$munmap(void* addr, size_t size)
{
REQUIRE_PROMISE(stdio);
if (!size)
return -EINVAL;
if (!is_user_range(VirtualAddress(addr), size))
return -EFAULT;
Range range_to_unmap { VirtualAddress(addr), size };
if (auto* whole_region = region_from_range(range_to_unmap)) {
if (!whole_region->is_mmap())
return -EPERM;
bool success = deallocate_region(*whole_region);
ASSERT(success);
return 0;
}
if (auto* old_region = region_containing(range_to_unmap)) {
if (!old_region->is_mmap())
return -EPERM;
auto new_regions = split_region_around_range(*old_region, range_to_unmap);
// We manually unmap the old region here, specifying that we *don't* want the VM deallocated.
old_region->unmap(Region::ShouldDeallocateVirtualMemoryRange::No);
deallocate_region(*old_region);
// Instead we give back the unwanted VM manually.
page_directory().range_allocator().deallocate(range_to_unmap);
// And finally we map the new region(s) using our page directory (they were just allocated and don't have one).
for (auto* new_region : new_regions) {
new_region->map(page_directory());
}
return 0;
}
// FIXME: We should also support munmap() across multiple regions. (#175)
return -EINVAL;
}
int Process::sys$mprotect(void* addr, size_t size, int prot)
{
REQUIRE_PROMISE(stdio);
if (!size)
return -EINVAL;
if (!is_user_range(VirtualAddress(addr), size))
return -EFAULT;
Range range_to_mprotect = { VirtualAddress(addr), size };
if (auto* whole_region = region_from_range(range_to_mprotect)) {
if (!whole_region->is_mmap())
return -EPERM;
if (!validate_mmap_prot(prot, whole_region->is_stack()))
return -EINVAL;
if (whole_region->access() == prot_to_region_access_flags(prot))
return 0;
if (whole_region->vmobject().is_inode()
&& !validate_inode_mmap_prot(*this, prot, static_cast<const InodeVMObject&>(whole_region->vmobject()).inode(), whole_region->is_shared())) {
return -EACCES;
}
whole_region->set_readable(prot & PROT_READ);
whole_region->set_writable(prot & PROT_WRITE);
whole_region->set_executable(prot & PROT_EXEC);
whole_region->remap();
return 0;
}
// Check if we can carve out the desired range from an existing region
if (auto* old_region = region_containing(range_to_mprotect)) {
if (!old_region->is_mmap())
return -EPERM;
if (!validate_mmap_prot(prot, old_region->is_stack()))
return -EINVAL;
if (old_region->access() == prot_to_region_access_flags(prot))
return 0;
if (old_region->vmobject().is_inode()
&& !validate_inode_mmap_prot(*this, prot, static_cast<const InodeVMObject&>(old_region->vmobject()).inode(), old_region->is_shared())) {
return -EACCES;
}
// This vector is the region(s) adjacent to our range.
// We need to allocate a new region for the range we wanted to change permission bits on.
auto adjacent_regions = split_region_around_range(*old_region, range_to_mprotect);
size_t new_range_offset_in_vmobject = old_region->offset_in_vmobject() + (range_to_mprotect.base().get() - old_region->range().base().get());
auto& new_region = allocate_split_region(*old_region, range_to_mprotect, new_range_offset_in_vmobject);
new_region.set_readable(prot & PROT_READ);
new_region.set_writable(prot & PROT_WRITE);
new_region.set_executable(prot & PROT_EXEC);
// Unmap the old region here, specifying that we *don't* want the VM deallocated.
old_region->unmap(Region::ShouldDeallocateVirtualMemoryRange::No);
deallocate_region(*old_region);
// Map the new regions using our page directory (they were just allocated and don't have one).
for (auto* adjacent_region : adjacent_regions) {
adjacent_region->map(page_directory());
}
new_region.map(page_directory());
return 0;
}
// FIXME: We should also support mprotect() across multiple regions. (#175) (#964)
return -EINVAL;
}
int Process::sys$madvise(void* address, size_t size, int advice)
{
REQUIRE_PROMISE(stdio);
if (!size)
return -EINVAL;
if (!is_user_range(VirtualAddress(address), size))
return -EFAULT;
auto* region = region_from_range({ VirtualAddress(address), size });
if (!region)
return -EINVAL;
if (!region->is_mmap())
return -EPERM;
if ((advice & MADV_SET_VOLATILE) && (advice & MADV_SET_NONVOLATILE))
return -EINVAL;
if (advice & MADV_SET_VOLATILE) {
if (!region->vmobject().is_purgeable())
return -EPERM;
auto& vmobject = static_cast<PurgeableVMObject&>(region->vmobject());
vmobject.set_volatile(true);
return 0;
}
if (advice & MADV_SET_NONVOLATILE) {
if (!region->vmobject().is_purgeable())
return -EPERM;
auto& vmobject = static_cast<PurgeableVMObject&>(region->vmobject());
if (!vmobject.is_volatile())
return 0;
vmobject.set_volatile(false);
bool was_purged = vmobject.was_purged();
vmobject.set_was_purged(false);
return was_purged ? 1 : 0;
}
if (advice & MADV_GET_VOLATILE) {
if (!region->vmobject().is_purgeable())
return -EPERM;
auto& vmobject = static_cast<PurgeableVMObject&>(region->vmobject());
return vmobject.is_volatile() ? 0 : 1;
}
return -EINVAL;
}
int Process::sys$purge(int mode)
{
REQUIRE_NO_PROMISES;
if (!is_superuser())
return -EPERM;
int purged_page_count = 0;
if (mode & PURGE_ALL_VOLATILE) {
NonnullRefPtrVector<PurgeableVMObject> vmobjects;
{
InterruptDisabler disabler;
MM.for_each_vmobject([&](auto& vmobject) {
if (vmobject.is_purgeable())
vmobjects.append(static_cast<PurgeableVMObject&>(vmobject));
return IterationDecision::Continue;
});
}
for (auto& vmobject : vmobjects) {
purged_page_count += vmobject.purge();
}
}
if (mode & PURGE_ALL_CLEAN_INODE) {
NonnullRefPtrVector<InodeVMObject> vmobjects;
{
InterruptDisabler disabler;
MM.for_each_vmobject([&](auto& vmobject) {
if (vmobject.is_inode())
vmobjects.append(static_cast<InodeVMObject&>(vmobject));
return IterationDecision::Continue;
});
}
for (auto& vmobject : vmobjects) {
purged_page_count += vmobject.release_all_clean_pages();
}
}
return purged_page_count;
}
int Process::sys$gethostname(char* buffer, ssize_t size)
{
REQUIRE_PROMISE(stdio);
if (size < 0)
return -EINVAL;
if (!validate_write(buffer, size))
return -EFAULT;
LOCKER(*s_hostname_lock);
if ((size_t)size < (s_hostname->length() + 1))
return -ENAMETOOLONG;
copy_to_user(buffer, s_hostname->characters(), s_hostname->length() + 1);
return 0;
}
pid_t Process::sys$fork(RegisterState& regs)
{
REQUIRE_PROMISE(proc);
Thread* child_first_thread = nullptr;
auto* child = new Process(child_first_thread, m_name, m_uid, m_gid, m_pid, m_ring, m_cwd, m_executable, m_tty, this);
child->m_root_directory = m_root_directory;
child->m_root_directory_relative_to_global_root = m_root_directory_relative_to_global_root;
child->m_promises = m_promises;
child->m_execpromises = m_execpromises;
child->m_veil_state = m_veil_state;
child->m_unveiled_paths = m_unveiled_paths;
child->m_fds = m_fds;
child->m_sid = m_sid;
child->m_pgid = m_pgid;
child->m_umask = m_umask;
#ifdef FORK_DEBUG
dbg() << "fork: child=" << child;
#endif
for (auto& region : m_regions) {
#ifdef FORK_DEBUG
dbg() << "fork: cloning Region{" << ®ion << "} '" << region.name() << "' @ " << region.vaddr();
#endif
auto& child_region = child->add_region(region.clone());
child_region.map(child->page_directory());
if (®ion == m_master_tls_region)
child->m_master_tls_region = child_region.make_weak_ptr();
}
child->m_extra_gids = m_extra_gids;
auto& child_tss = child_first_thread->m_tss;
child_tss.eax = 0; // fork() returns 0 in the child :^)
child_tss.ebx = regs.ebx;
child_tss.ecx = regs.ecx;
child_tss.edx = regs.edx;
child_tss.ebp = regs.ebp;
child_tss.esp = regs.userspace_esp;
child_tss.esi = regs.esi;
child_tss.edi = regs.edi;
child_tss.eflags = regs.eflags;
child_tss.eip = regs.eip;
child_tss.cs = regs.cs;
child_tss.ds = regs.ds;
child_tss.es = regs.es;
child_tss.fs = regs.fs;
child_tss.gs = regs.gs;
child_tss.ss = regs.userspace_ss;
#ifdef FORK_DEBUG
dbg() << "fork: child will begin executing at " << String::format("%w", child_tss.cs) << ":" << String::format("%x", child_tss.eip) << " with stack " << String::format("%w", child_tss.ss) << ":" << String::format("%x", child_tss.esp) << ", kstack " << String::format("%w", child_tss.ss0) << ":" << String::format("%x", child_tss.esp0);
#endif
{
InterruptDisabler disabler;
g_processes->prepend(child);
}
#ifdef TASK_DEBUG
klog() << "Process " << child->pid() << " (" << child->name().characters() << ") forked from " << m_pid << " @ " << String::format("%p", child_tss.eip);
#endif
child_first_thread->set_state(Thread::State::Skip1SchedulerPass);
return child->pid();
}
void Process::kill_threads_except_self()
{
InterruptDisabler disabler;
if (m_thread_count <= 1)
return;
for_each_thread([&](Thread& thread) {
if (&thread == Thread::current
|| thread.state() == Thread::State::Dead
|| thread.state() == Thread::State::Dying)
return IterationDecision::Continue;
// At this point, we have no joiner anymore
thread.m_joiner = nullptr;
thread.set_should_die();
if (thread.state() != Thread::State::Dead)
thread.set_state(Thread::State::Dying);
return IterationDecision::Continue;
});
big_lock().clear_waiters();
}
void Process::kill_all_threads()
{
for_each_thread([&](Thread& thread) {
thread.set_should_die();
return IterationDecision::Continue;
});
}
int Process::do_exec(NonnullRefPtr<FileDescription> main_program_description, Vector<String> arguments, Vector<String> environment, RefPtr<FileDescription> interpreter_description)
{
ASSERT(is_ring3());
auto path = main_program_description->absolute_path();
dbg() << "do_exec(" << path << ")";
size_t total_blob_size = 0;
for (auto& a : arguments)
total_blob_size += a.length() + 1;
for (auto& e : environment)
total_blob_size += e.length() + 1;
size_t total_meta_size = sizeof(char*) * (arguments.size() + 1) + sizeof(char*) * (environment.size() + 1);
// FIXME: How much stack space does process startup need?
if ((total_blob_size + total_meta_size) >= Thread::default_userspace_stack_size)
return -E2BIG;
auto parts = path.split('/');
if (parts.is_empty())
return -ENOENT;
auto& inode = interpreter_description ? *interpreter_description->inode() : *main_program_description->inode();
auto vmobject = SharedInodeVMObject::create_with_inode(inode);
if (static_cast<const SharedInodeVMObject&>(*vmobject).writable_mappings()) {
dbg() << "Refusing to execute a write-mapped program";
return -ETXTBSY;
}
// Disable profiling temporarily in case it's running on this process.
bool was_profiling = is_profiling();
TemporaryChange profiling_disabler(m_profiling, false);
// Mark this thread as the current thread that does exec
// No other thread from this process will be scheduled to run
m_exec_tid = Thread::current->tid();
auto old_page_directory = move(m_page_directory);
auto old_regions = move(m_regions);
m_page_directory = PageDirectory::create_for_userspace(*this);
#ifdef MM_DEBUG
dbg() << "Process " << pid() << " exec: PD=" << m_page_directory.ptr() << " created";
#endif
InodeMetadata loader_metadata;
// FIXME: Hoooo boy this is a hack if I ever saw one.
// This is the 'random' offset we're giving to our ET_DYN exectuables to start as.
// It also happens to be the static Virtual Addresss offset every static exectuable gets :)
// Without this, some assumptions by the ELF loading hooks below are severely broken.
// 0x08000000 is a verified random number chosen by random dice roll https://xkcd.com/221/
u32 totally_random_offset = interpreter_description ? 0x08000000 : 0;
// FIXME: We should be able to load both the PT_INTERP interpreter and the main program... once the RTLD is smart enough
if (interpreter_description) {
loader_metadata = interpreter_description->metadata();
// we don't need the interpreter file desciption after we've loaded (or not) it into memory
interpreter_description = nullptr;
} else {
loader_metadata = main_program_description->metadata();
}
auto region = MM.allocate_kernel_region_with_vmobject(*vmobject, PAGE_ROUND_UP(loader_metadata.size), "ELF loading", Region::Access::Read);
if (!region)
return -ENOMEM;
Region* master_tls_region { nullptr };
size_t master_tls_size = 0;
size_t master_tls_alignment = 0;
u32 entry_eip = 0;
MM.enter_process_paging_scope(*this);
OwnPtr<ELFLoader> loader;
{
ArmedScopeGuard rollback_regions_guard([&]() {
ASSERT(Process::current == this);
m_page_directory = move(old_page_directory);
m_regions = move(old_regions);
MM.enter_process_paging_scope(*this);
});
loader = make<ELFLoader>(region->vaddr().as_ptr(), loader_metadata.size);
// Load the correct executable -- either interp or main program.
// FIXME: Once we actually load both interp and main, we'll need to be more clever about this.
// In that case, both will be ET_DYN objects, so they'll both be completely relocatable.
// That means, we can put them literally anywhere in User VM space (ASLR anyone?).
// ALSO FIXME: Reminder to really really fix that 'totally random offset' business.
loader->map_section_hook = [&](VirtualAddress vaddr, size_t size, size_t alignment, size_t offset_in_image, bool is_readable, bool is_writable, bool is_executable, const String& name) -> u8* {
ASSERT(size);
ASSERT(alignment == PAGE_SIZE);
int prot = 0;
if (is_readable)
prot |= PROT_READ;
if (is_writable)
prot |= PROT_WRITE;
if (is_executable)
prot |= PROT_EXEC;
if (auto* region = allocate_region_with_vmobject(vaddr.offset(totally_random_offset), size, *vmobject, offset_in_image, String(name), prot)) {
region->set_shared(true);
return region->vaddr().as_ptr();
}
return nullptr;
};
loader->alloc_section_hook = [&](VirtualAddress vaddr, size_t size, size_t alignment, bool is_readable, bool is_writable, const String& name) -> u8* {
ASSERT(size);
ASSERT(alignment == PAGE_SIZE);
int prot = 0;
if (is_readable)
prot |= PROT_READ;
if (is_writable)
prot |= PROT_WRITE;
if (auto* region = allocate_region(vaddr.offset(totally_random_offset), size, String(name), prot))
return region->vaddr().as_ptr();
return nullptr;
};
// FIXME: Move TLS region allocation to userspace: LibC and the dynamic loader.
// LibC if we end up with a statically linked executable, and the
// dynamic loader so that it can create new TLS blocks for each shared libarary
// that gets loaded as part of DT_NEEDED processing, and via dlopen()
// If that doesn't happen quickly, at least pass the location of the TLS region
// some ELF Auxilliary Vector so the loader can use it/create new ones as necessary.
loader->tls_section_hook = [&](size_t size, size_t alignment) {
ASSERT(size);
master_tls_region = allocate_region({}, size, String(), PROT_READ | PROT_WRITE);
master_tls_size = size;
master_tls_alignment = alignment;
return master_tls_region->vaddr().as_ptr();
};
bool success = loader->load();
if (!success) {
klog() << "do_exec: Failure loading " << path.characters();
return -ENOEXEC;
}
// FIXME: Validate that this virtual address is within executable region,
// instead of just non-null. You could totally have a DSO with entry point of
// the beginning of the text segement.
if (!loader->entry().offset(totally_random_offset).get()) {
klog() << "do_exec: Failure loading " << path.characters() << ", entry pointer is invalid! (" << loader->entry().offset(totally_random_offset) << ")";
return -ENOEXEC;
}
rollback_regions_guard.disarm();
// NOTE: At this point, we've committed to the new executable.
entry_eip = loader->entry().offset(totally_random_offset).get();
kill_threads_except_self();
#ifdef EXEC_DEBUG
klog() << "Memory layout after ELF load:";
dump_regions();
#endif
}
m_executable = main_program_description->custody();
m_promises = m_execpromises;
m_veil_state = VeilState::None;
m_unveiled_paths.clear();
// Copy of the master TLS region that we will clone for new threads
m_master_tls_region = master_tls_region->make_weak_ptr();
auto main_program_metadata = main_program_description->metadata();
if (!(main_program_description->custody()->mount_flags() & MS_NOSUID)) {
if (main_program_metadata.is_setuid())
m_euid = main_program_metadata.uid;
if (main_program_metadata.is_setgid())
m_egid = main_program_metadata.gid;
}
Thread::current->set_default_signal_dispositions();
Thread::current->m_signal_mask = 0;
Thread::current->m_pending_signals = 0;
m_futex_queues.clear();
m_region_lookup_cache = {};
disown_all_shared_buffers();
for (size_t i = 0; i < m_fds.size(); ++i) {
auto& daf = m_fds[i];
if (daf.description && daf.flags & FD_CLOEXEC) {
daf.description->close();
daf = {};
}
}
Thread* new_main_thread = nullptr;
if (Process::current == this) {
new_main_thread = Thread::current;
} else {
for_each_thread([&](auto& thread) {
new_main_thread = &thread;
return IterationDecision::Break;
});
}
ASSERT(new_main_thread);
// NOTE: We create the new stack before disabling interrupts since it will zero-fault
// and we don't want to deal with faults after this point.
u32 new_userspace_esp = new_main_thread->make_userspace_stack_for_main_thread(move(arguments), move(environment));
// We cli() manually here because we don't want to get interrupted between do_exec() and Schedule::yield().
// The reason is that the task redirection we've set up above will be clobbered by the timer IRQ.
// If we used an InterruptDisabler that sti()'d on exit, we might timer tick'd too soon in exec().
if (Process::current == this)
cli();
// NOTE: Be careful to not trigger any page faults below!
Scheduler::prepare_to_modify_tss(*new_main_thread);
m_name = parts.take_last();
new_main_thread->set_name(m_name);
auto& tss = new_main_thread->m_tss;
u32 old_esp0 = tss.esp0;
m_master_tls_size = master_tls_size;
m_master_tls_alignment = master_tls_alignment;
m_pid = new_main_thread->tid();
new_main_thread->make_thread_specific_region({});
new_main_thread->reset_fpu_state();
memset(&tss, 0, sizeof(TSS32));
tss.iomapbase = sizeof(TSS32);
tss.eflags = 0x0202;
tss.eip = entry_eip;
tss.cs = 0x1b;
tss.ds = 0x23;
tss.es = 0x23;
tss.fs = 0x23;
tss.gs = thread_specific_selector() | 3;
tss.ss = 0x23;
tss.cr3 = page_directory().cr3();
tss.esp = new_userspace_esp;
tss.ss0 = 0x10;
tss.esp0 = old_esp0;
tss.ss2 = m_pid;
#ifdef TASK_DEBUG
klog() << "Process exec'd " << path.characters() << " @ " << String::format("%p", tss.eip);
#endif
if (was_profiling)
Profiling::did_exec(path);
new_main_thread->set_state(Thread::State::Skip1SchedulerPass);
big_lock().force_unlock_if_locked();
return 0;
}
static KResultOr<Vector<String>> find_shebang_interpreter_for_executable(const char first_page[], int nread)
{
int word_start = 2;
int word_length = 0;
if (nread > 2 && first_page[0] == '#' && first_page[1] == '!') {
Vector<String> interpreter_words;
for (int i = 2; i < nread; ++i) {
if (first_page[i] == '\n') {
break;
}
if (first_page[i] != ' ') {
++word_length;
}
if (first_page[i] == ' ') {
if (word_length > 0) {
interpreter_words.append(String(&first_page[word_start], word_length));
}
word_length = 0;
word_start = i + 1;
}
}
if (word_length > 0)
interpreter_words.append(String(&first_page[word_start], word_length));
if (!interpreter_words.is_empty())
return interpreter_words;
}
return KResult(-ENOEXEC);
}
KResultOr<NonnullRefPtr<FileDescription>> Process::find_elf_interpreter_for_executable(const String& path, char (&first_page)[PAGE_SIZE], int nread, size_t file_size)
{
if (nread < (int)sizeof(Elf32_Ehdr))
return KResult(-ENOEXEC);
auto elf_header = (Elf32_Ehdr*)first_page;
if (!ELFImage::validate_elf_header(*elf_header, file_size)) {
dbg() << "exec(" << path << "): File has invalid ELF header";
return KResult(-ENOEXEC);
}
// Not using KResultOr here because we'll want to do the same thing in userspace in the RTLD
String interpreter_path;
if (!ELFImage::validate_program_headers(*elf_header, file_size, (u8*)first_page, nread, interpreter_path)) {
dbg() << "exec(" << path << "): File has invalid ELF Program headers";
return KResult(-ENOEXEC);
}
if (!interpreter_path.is_empty()) {
// Programs with an interpreter better be relocatable executables or we don't know what to do...
if (elf_header->e_type != ET_DYN)
return KResult(-ENOEXEC);
dbg() << "exec(" << path << "): Using program interpreter " << interpreter_path;
auto interp_result = VFS::the().open(interpreter_path, O_EXEC, 0, current_directory());
if (interp_result.is_error()) {
dbg() << "exec(" << path << "): Unable to open program interpreter " << interpreter_path;
return interp_result.error();
}
auto interpreter_description = interp_result.value();
auto interp_metadata = interpreter_description->metadata();
ASSERT(interpreter_description->inode());
// Validate the program interpreter as a valid elf binary.
// If your program interpreter is a #! file or something, it's time to stop playing games :)
if (interp_metadata.size < (int)sizeof(Elf32_Ehdr))
return KResult(-ENOEXEC);
memset(first_page, 0, sizeof(first_page));
nread = interpreter_description->read((u8*)&first_page, sizeof(first_page));
if (nread < (int)sizeof(Elf32_Ehdr))
return KResult(-ENOEXEC);
elf_header = (Elf32_Ehdr*)first_page;
if (!ELFImage::validate_elf_header(*elf_header, interp_metadata.size)) {
dbg() << "exec(" << path << "): Interpreter (" << interpreter_description->absolute_path() << ") has invalid ELF header";
return KResult(-ENOEXEC);
}
// Not using KResultOr here because we'll want to do the same thing in userspace in the RTLD
String interpreter_interpreter_path;
if (!ELFImage::validate_program_headers(*elf_header, interp_metadata.size, (u8*)first_page, nread, interpreter_interpreter_path)) {
dbg() << "exec(" << path << "): Interpreter (" << interpreter_description->absolute_path() << ") has invalid ELF Program headers";
return KResult(-ENOEXEC);
}
if (!interpreter_interpreter_path.is_empty()) {
dbg() << "exec(" << path << "): Interpreter (" << interpreter_description->absolute_path() << ") has its own interpreter (" << interpreter_interpreter_path << ")! No thank you!";
return KResult(-ELOOP);
}
return interpreter_description;
}
if (elf_header->e_type != ET_EXEC) {
// We can't exec an ET_REL, that's just an object file from the compiler
// If it's ET_DYN with no PT_INTERP, then we can't load it properly either
return KResult(-ENOEXEC);
}
// No interpreter, but, path refers to a valid elf image
return KResult(KSuccess);
}
int Process::exec(String path, Vector<String> arguments, Vector<String> environment, int recursion_depth)
{
if (recursion_depth > 2) {
dbg() << "exec(" << path << "): SHENANIGANS! recursed too far trying to find #! interpreter";
return -ELOOP;
}
// Open the file to check what kind of binary format it is
// Currently supported formats:
// - #! interpreted file
// - ELF32
// * ET_EXEC binary that just gets loaded
// * ET_DYN binary that requires a program interpreter
//
auto result = VFS::the().open(path, O_EXEC, 0, current_directory());
if (result.is_error())
return result.error();
auto description = result.value();
auto metadata = description->metadata();
// Always gonna need at least 3 bytes. these are for #!X
if (metadata.size < 3)
return -ENOEXEC;
ASSERT(description->inode());
// Read the first page of the program into memory so we can validate the binfmt of it
char first_page[PAGE_SIZE];
int nread = description->read((u8*)&first_page, sizeof(first_page));
// 1) #! interpreted file
auto shebang_result = find_shebang_interpreter_for_executable(first_page, nread);
if (!shebang_result.is_error()) {
Vector<String> new_arguments(shebang_result.value());
new_arguments.append(path);
arguments.remove(0);
new_arguments.append(move(arguments));
return exec(shebang_result.value().first(), move(new_arguments), move(environment), ++recursion_depth);
}
// #2) ELF32 for i386
auto elf_result = find_elf_interpreter_for_executable(path, first_page, nread, metadata.size);
RefPtr<FileDescription> interpreter_description;
// We're getting either an interpreter, an error, or KSuccess (i.e. no interpreter but file checks out)
if (!elf_result.is_error())
interpreter_description = elf_result.value();
else if (elf_result.error().is_error())
return elf_result.error();
// The bulk of exec() is done by do_exec(), which ensures that all locals
// are cleaned up by the time we yield-teleport below.
int rc = do_exec(move(description), move(arguments), move(environment), move(interpreter_description));
m_exec_tid = 0;
if (rc < 0)
return rc;
if (Process::current == this) {
Scheduler::yield();
ASSERT_NOT_REACHED();
}
return 0;
}
int Process::sys$execve(const Syscall::SC_execve_params* user_params)
{
REQUIRE_PROMISE(exec);
// NOTE: Be extremely careful with allocating any kernel memory in exec().
// On success, the kernel stack will be lost.
Syscall::SC_execve_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (params.arguments.length > ARG_MAX || params.environment.length > ARG_MAX)
return -E2BIG;
String path;
{
auto path_arg = get_syscall_path_argument(params.path);
if (path_arg.is_error())
return path_arg.error();
path = path_arg.value();
}
auto copy_user_strings = [&](const auto& list, auto& output) {
if (!list.length)
return true;
if (!validate_read_typed(list.strings, list.length))
return false;
Vector<Syscall::StringArgument, 32> strings;
strings.resize(list.length);
copy_from_user(strings.data(), list.strings, list.length * sizeof(Syscall::StringArgument));
for (size_t i = 0; i < list.length; ++i) {
auto string = validate_and_copy_string_from_user(strings[i]);
if (string.is_null())
return false;
output.append(move(string));
}
return true;
};
Vector<String> arguments;
if (!copy_user_strings(params.arguments, arguments))
return -EFAULT;
Vector<String> environment;
if (!copy_user_strings(params.environment, environment))
return -EFAULT;
int rc = exec(move(path), move(arguments), move(environment));
ASSERT(rc < 0); // We should never continue after a successful exec!
return rc;
}
Process* Process::create_user_process(Thread*& first_thread, const String& path, uid_t uid, gid_t gid, pid_t parent_pid, int& error, Vector<String>&& arguments, Vector<String>&& environment, TTY* tty)
{
auto parts = path.split('/');
if (arguments.is_empty()) {
arguments.append(parts.last());
}
RefPtr<Custody> cwd;
RefPtr<Custody> root;
{
InterruptDisabler disabler;
if (auto* parent = Process::from_pid(parent_pid)) {
cwd = parent->m_cwd;
root = parent->m_root_directory;
}
}
if (!cwd)
cwd = VFS::the().root_custody();
if (!root)
root = VFS::the().root_custody();
auto* process = new Process(first_thread, parts.take_last(), uid, gid, parent_pid, Ring3, move(cwd), nullptr, tty);
process->m_fds.resize(m_max_open_file_descriptors);
auto& device_to_use_as_tty = tty ? (CharacterDevice&)*tty : NullDevice::the();
auto description = device_to_use_as_tty.open(O_RDWR).value();
process->m_fds[0].set(*description);
process->m_fds[1].set(*description);
process->m_fds[2].set(*description);
error = process->exec(path, move(arguments), move(environment));
if (error != 0) {
delete process;
return nullptr;
}
{
InterruptDisabler disabler;
g_processes->prepend(process);
}
#ifdef TASK_DEBUG
klog() << "Process " << process->pid() << " (" << process->name().characters() << ") spawned @ " << String::format("%p", first_thread->tss().eip);
#endif
error = 0;
return process;
}
Process* Process::create_kernel_process(Thread*& first_thread, String&& name, void (*e)())
{
auto* process = new Process(first_thread, move(name), (uid_t)0, (gid_t)0, (pid_t)0, Ring0);
first_thread->tss().eip = (FlatPtr)e;
if (process->pid() != 0) {
InterruptDisabler disabler;
g_processes->prepend(process);
#ifdef TASK_DEBUG
klog() << "Kernel process " << process->pid() << " (" << process->name().characters() << ") spawned @ " << String::format("%p", first_thread->tss().eip);
#endif
}
first_thread->set_state(Thread::State::Runnable);
return process;
}
Process::Process(Thread*& first_thread, const String& name, uid_t uid, gid_t gid, pid_t ppid, RingLevel ring, RefPtr<Custody> cwd, RefPtr<Custody> executable, TTY* tty, Process* fork_parent)
: m_name(move(name))
, m_pid(allocate_pid())
, m_uid(uid)
, m_gid(gid)
, m_euid(uid)
, m_egid(gid)
, m_ring(ring)
, m_executable(move(executable))
, m_cwd(move(cwd))
, m_tty(tty)
, m_ppid(ppid)
{
#ifdef PROCESS_DEBUG
dbg() << "Created new process " << m_name << "(" << m_pid << ")";
#endif
m_page_directory = PageDirectory::create_for_userspace(*this, fork_parent ? &fork_parent->page_directory().range_allocator() : nullptr);
#ifdef MM_DEBUG
dbg() << "Process " << pid() << " ctor: PD=" << m_page_directory.ptr() << " created";
#endif
if (fork_parent) {
// NOTE: fork() doesn't clone all threads; the thread that called fork() becomes the only thread in the new process.
first_thread = Thread::current->clone(*this);
} else {
// NOTE: This non-forked code path is only taken when the kernel creates a process "manually" (at boot.)
first_thread = new Thread(*this);
}
}
Process::~Process()
{
ASSERT(thread_count() == 0);
}
void Process::dump_regions()
{
klog() << "Process regions:";
klog() << "BEGIN END SIZE ACCESS NAME";
for (auto& region : m_regions) {
klog() << String::format("%08x", region.vaddr().get()) << " -- " << String::format("%08x", region.vaddr().offset(region.size() - 1).get()) << " " << String::format("%08x", region.size()) << " " << (region.is_readable() ? 'R' : ' ') << (region.is_writable() ? 'W' : ' ') << (region.is_executable() ? 'X' : ' ') << (region.is_shared() ? 'S' : ' ') << (region.is_stack() ? 'T' : ' ') << (region.vmobject().is_purgeable() ? 'P' : ' ') << " " << region.name().characters();
}
MM.dump_kernel_regions();
}
void Process::sys$exit(int status)
{
cli();
#ifdef TASK_DEBUG
klog() << "sys$exit: exit with status " << status;
#endif
if (status != 0)
dump_backtrace();
m_termination_status = status;
m_termination_signal = 0;
die();
Thread::current->die_if_needed();
ASSERT_NOT_REACHED();
}
void signal_trampoline_dummy(void)
{
// The trampoline preserves the current eax, pushes the signal code and
// then calls the signal handler. We do this because, when interrupting a
// blocking syscall, that syscall may return some special error code in eax;
// This error code would likely be overwritten by the signal handler, so it's
// neccessary to preserve it here.
asm(
".intel_syntax noprefix\n"
"asm_signal_trampoline:\n"
"push ebp\n"
"mov ebp, esp\n"
"push eax\n" // we have to store eax 'cause it might be the return value from a syscall
"sub esp, 4\n" // align the stack to 16 bytes
"mov eax, [ebp+12]\n" // push the signal code
"push eax\n"
"call [ebp+8]\n" // call the signal handler
"add esp, 8\n"
"mov eax, %P0\n"
"int 0x82\n" // sigreturn syscall
"asm_signal_trampoline_end:\n"
".att_syntax" ::"i"(Syscall::SC_sigreturn));
}
extern "C" void asm_signal_trampoline(void);
extern "C" void asm_signal_trampoline_end(void);
void create_signal_trampolines()
{
InterruptDisabler disabler;
// NOTE: We leak this region.
auto* trampoline_region = MM.allocate_user_accessible_kernel_region(PAGE_SIZE, "Signal trampolines", Region::Access::Read | Region::Access::Write | Region::Access::Execute, false).leak_ptr();
g_return_to_ring3_from_signal_trampoline = trampoline_region->vaddr();
u8* trampoline = (u8*)asm_signal_trampoline;
u8* trampoline_end = (u8*)asm_signal_trampoline_end;
size_t trampoline_size = trampoline_end - trampoline;
{
SmapDisabler disabler;
u8* code_ptr = (u8*)trampoline_region->vaddr().as_ptr();
memcpy(code_ptr, trampoline, trampoline_size);
}
trampoline_region->set_writable(false);
trampoline_region->remap();
}
void create_kernel_info_page()
{
auto* info_page_region_for_userspace = MM.allocate_user_accessible_kernel_region(PAGE_SIZE, "Kernel info page", Region::Access::Read).leak_ptr();
auto* info_page_region_for_kernel = MM.allocate_kernel_region_with_vmobject(info_page_region_for_userspace->vmobject(), PAGE_SIZE, "Kernel info page", Region::Access::Read | Region::Access::Write).leak_ptr();
s_info_page_address_for_userspace = info_page_region_for_userspace->vaddr();
s_info_page_address_for_kernel = info_page_region_for_kernel->vaddr();
memset(s_info_page_address_for_kernel.as_ptr(), 0, PAGE_SIZE);
}
int Process::sys$sigreturn(RegisterState& registers)
{
REQUIRE_PROMISE(stdio);
SmapDisabler disabler;
//Here, we restore the state pushed by dispatch signal and asm_signal_trampoline.
u32* stack_ptr = (u32*)registers.userspace_esp;
u32 smuggled_eax = *stack_ptr;
//pop the stored eax, ebp, return address, handler and signal code
stack_ptr += 5;
Thread::current->m_signal_mask = *stack_ptr;
stack_ptr++;
//pop edi, esi, ebp, esp, ebx, edx, ecx and eax
memcpy(®isters.edi, stack_ptr, 8 * sizeof(FlatPtr));
stack_ptr += 8;
registers.eip = *stack_ptr;
stack_ptr++;
registers.eflags = *stack_ptr;
stack_ptr++;
registers.userspace_esp = registers.esp;
return smuggled_eax;
}
void Process::crash(int signal, u32 eip)
{
ASSERT_INTERRUPTS_DISABLED();
ASSERT(!is_dead());
ASSERT(Process::current == this);
if (eip >= 0xc0000000 && ksyms_ready) {
auto* ksym = ksymbolicate(eip);
dbg() << "\033[31;1m" << String::format("%p", eip) << " " << (ksym ? demangle(ksym->name) : "(k?)") << " +" << (ksym ? eip - ksym->address : 0) << "\033[0m\n";
} else if (auto elf_bundle = this->elf_bundle()) {
dbg() << "\033[31;1m" << String::format("%p", eip) << " " << elf_bundle->elf_loader->symbolicate(eip) << "\033[0m\n";
} else {
dbg() << "\033[31;1m" << String::format("%p", eip) << " (?)\033[0m\n";
}
dump_backtrace();
m_termination_signal = signal;
dump_regions();
ASSERT(is_ring3());
die();
// We can not return from here, as there is nowhere
// to unwind to, so die right away.
Thread::current->die_if_needed();
ASSERT_NOT_REACHED();
}
Process* Process::from_pid(pid_t pid)
{
ASSERT_INTERRUPTS_DISABLED();
for (auto& process : *g_processes) {
if (process.pid() == pid)
return &process;
}
return nullptr;
}
RefPtr<FileDescription> Process::file_description(int fd) const
{
if (fd < 0)
return nullptr;
if (static_cast<size_t>(fd) < m_fds.size())
return m_fds[fd].description.ptr();
return nullptr;
}
int Process::fd_flags(int fd) const
{
if (fd < 0)
return -1;
if (static_cast<size_t>(fd) < m_fds.size())
return m_fds[fd].flags;
return -1;
}
ssize_t Process::sys$get_dir_entries(int fd, void* buffer, ssize_t size)
{
REQUIRE_PROMISE(stdio);
if (size < 0)
return -EINVAL;
if (!validate_write(buffer, size))
return -EFAULT;
auto description = file_description(fd);
if (!description)
return -EBADF;
return description->get_dir_entries((u8*)buffer, size);
}
int Process::sys$lseek(int fd, off_t offset, int whence)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(fd);
if (!description)
return -EBADF;
return description->seek(offset, whence);
}
int Process::sys$ttyname_r(int fd, char* buffer, ssize_t size)
{
REQUIRE_PROMISE(tty);
if (size < 0)
return -EINVAL;
if (!validate_write(buffer, size))
return -EFAULT;
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_tty())
return -ENOTTY;
String tty_name = description->tty()->tty_name();
if ((size_t)size < tty_name.length() + 1)
return -ERANGE;
copy_to_user(buffer, tty_name.characters(), tty_name.length() + 1);
return 0;
}
int Process::sys$ptsname_r(int fd, char* buffer, ssize_t size)
{
REQUIRE_PROMISE(tty);
if (size < 0)
return -EINVAL;
if (!validate_write(buffer, size))
return -EFAULT;
auto description = file_description(fd);
if (!description)
return -EBADF;
auto* master_pty = description->master_pty();
if (!master_pty)
return -ENOTTY;
auto pts_name = master_pty->pts_name();
if ((size_t)size < pts_name.length() + 1)
return -ERANGE;
copy_to_user(buffer, pts_name.characters(), pts_name.length() + 1);
return 0;
}
ssize_t Process::sys$writev(int fd, const struct iovec* iov, int iov_count)
{
REQUIRE_PROMISE(stdio);
if (iov_count < 0)
return -EINVAL;
if (!validate_read_typed(iov, iov_count))
return -EFAULT;
u64 total_length = 0;
Vector<iovec, 32> vecs;
vecs.resize(iov_count);
copy_from_user(vecs.data(), iov, iov_count * sizeof(iovec));
for (auto& vec : vecs) {
if (!validate_read(vec.iov_base, vec.iov_len))
return -EFAULT;
total_length += vec.iov_len;
if (total_length > INT32_MAX)
return -EINVAL;
}
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_writable())
return -EBADF;
int nwritten = 0;
for (auto& vec : vecs) {
int rc = do_write(*description, (const u8*)vec.iov_base, vec.iov_len);
if (rc < 0) {
if (nwritten == 0)
return rc;
return nwritten;
}
nwritten += rc;
}
return nwritten;
}
ssize_t Process::do_write(FileDescription& description, const u8* data, int data_size)
{
ssize_t nwritten = 0;
if (!description.is_blocking()) {
if (!description.can_write())
return -EAGAIN;
}
if (description.should_append()) {
#ifdef IO_DEBUG
dbg() << "seeking to end (O_APPEND)";
#endif
description.seek(0, SEEK_END);
}
while (nwritten < data_size) {
#ifdef IO_DEBUG
dbg() << "while " << nwritten << " < " << size;
#endif
if (!description.can_write()) {
#ifdef IO_DEBUG
dbg() << "block write on " << description.absolute_path();
#endif
if (Thread::current->block<Thread::WriteBlocker>(description) != Thread::BlockResult::WokeNormally) {
if (nwritten == 0)
return -EINTR;
}
}
ssize_t rc = description.write(data + nwritten, data_size - nwritten);
#ifdef IO_DEBUG
dbg() << " -> write returned " << rc;
#endif
if (rc < 0) {
if (nwritten)
return nwritten;
return rc;
}
if (rc == 0)
break;
nwritten += rc;
}
return nwritten;
}
ssize_t Process::sys$write(int fd, const u8* data, ssize_t size)
{
REQUIRE_PROMISE(stdio);
if (size < 0)
return -EINVAL;
if (size == 0)
return 0;
if (!validate_read(data, size))
return -EFAULT;
#ifdef DEBUG_IO
dbg() << "sys$write(" << fd << ", " << (const void*)(data) << ", " << size << ")";
#endif
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_writable())
return -EBADF;
return do_write(*description, data, size);
}
ssize_t Process::sys$read(int fd, u8* buffer, ssize_t size)
{
REQUIRE_PROMISE(stdio);
if (size < 0)
return -EINVAL;
if (size == 0)
return 0;
if (!validate_write(buffer, size))
return -EFAULT;
#ifdef DEBUG_IO
dbg() << "sys$read(" << fd << ", " << (const void*)buffer << ", " << size << ")";
#endif
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_readable())
return -EBADF;
if (description->is_directory())
return -EISDIR;
if (description->is_blocking()) {
if (!description->can_read()) {
if (Thread::current->block<Thread::ReadBlocker>(*description) != Thread::BlockResult::WokeNormally)
return -EINTR;
if (!description->can_read())
return -EAGAIN;
}
}
return description->read(buffer, size);
}
int Process::sys$close(int fd)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(fd);
#ifdef DEBUG_IO
dbg() << "sys$close(" << fd << ") " << description.ptr();
#endif
if (!description)
return -EBADF;
int rc = description->close();
m_fds[fd] = {};
return rc;
}
int Process::sys$utime(const char* user_path, size_t path_length, const utimbuf* user_buf)
{
REQUIRE_PROMISE(fattr);
if (user_buf && !validate_read_typed(user_buf))
return -EFAULT;
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
utimbuf buf;
if (user_buf) {
copy_from_user(&buf, user_buf);
} else {
auto now = kgettimeofday();
buf = { now.tv_sec, now.tv_sec };
}
return VFS::the().utime(path.value(), current_directory(), buf.actime, buf.modtime);
}
int Process::sys$access(const char* user_path, size_t path_length, int mode)
{
REQUIRE_PROMISE(rpath);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
return VFS::the().access(path.value(), mode, current_directory());
}
int Process::sys$fcntl(int fd, int cmd, u32 arg)
{
REQUIRE_PROMISE(stdio);
#ifdef DEBUG_IO
dbg() << "sys$fcntl: fd=" << fd << ", cmd=" << cmd << ", arg=" << arg;
#endif
auto description = file_description(fd);
if (!description)
return -EBADF;
// NOTE: The FD flags are not shared between FileDescription objects.
// This means that dup() doesn't copy the FD_CLOEXEC flag!
switch (cmd) {
case F_DUPFD: {
int arg_fd = (int)arg;
if (arg_fd < 0)
return -EINVAL;
int new_fd = alloc_fd(arg_fd);
if (new_fd < 0)
return new_fd;
m_fds[new_fd].set(*description);
return new_fd;
}
case F_GETFD:
return m_fds[fd].flags;
case F_SETFD:
m_fds[fd].flags = arg;
break;
case F_GETFL:
return description->file_flags();
case F_SETFL:
description->set_file_flags(arg);
break;
default:
ASSERT_NOT_REACHED();
}
return 0;
}
int Process::sys$fstat(int fd, stat* user_statbuf)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(user_statbuf))
return -EFAULT;
auto description = file_description(fd);
if (!description)
return -EBADF;
stat buffer;
memset(&buffer, 0, sizeof(buffer));
int rc = description->fstat(buffer);
copy_to_user(user_statbuf, &buffer);
return rc;
}
int Process::sys$stat(const Syscall::SC_stat_params* user_params)
{
REQUIRE_PROMISE(rpath);
Syscall::SC_stat_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!validate_write_typed(params.statbuf))
return -EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
auto metadata_or_error = VFS::the().lookup_metadata(path.value(), current_directory(), params.follow_symlinks ? 0 : O_NOFOLLOW_NOERROR);
if (metadata_or_error.is_error())
return metadata_or_error.error();
stat statbuf;
auto result = metadata_or_error.value().stat(statbuf);
if (result.is_error())
return result;
copy_to_user(params.statbuf, &statbuf);
return 0;
}
template<typename DataType, typename SizeType>
bool Process::validate(const Syscall::MutableBufferArgument<DataType, SizeType>& buffer)
{
return validate_write(buffer.data, buffer.size);
}
template<typename DataType, typename SizeType>
bool Process::validate(const Syscall::ImmutableBufferArgument<DataType, SizeType>& buffer)
{
return validate_read(buffer.data, buffer.size);
}
String Process::validate_and_copy_string_from_user(const char* user_characters, size_t user_length) const
{
if (user_length == 0)
return String::empty();
if (!user_characters)
return {};
if (!validate_read(user_characters, user_length))
return {};
SmapDisabler disabler;
size_t measured_length = strnlen(user_characters, user_length);
return String(user_characters, measured_length);
}
String Process::validate_and_copy_string_from_user(const Syscall::StringArgument& string) const
{
return validate_and_copy_string_from_user(string.characters, string.length);
}
int Process::sys$readlink(const Syscall::SC_readlink_params* user_params)
{
REQUIRE_PROMISE(rpath);
Syscall::SC_readlink_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!validate(params.buffer))
return -EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
auto result = VFS::the().open(path.value(), O_RDONLY | O_NOFOLLOW_NOERROR, 0, current_directory());
if (result.is_error())
return result.error();
auto description = result.value();
if (!description->metadata().is_symlink())
return -EINVAL;
auto contents = description->read_entire_file();
if (!contents)
return -EIO; // FIXME: Get a more detailed error from VFS.
auto link_target = String::copy(contents);
if (link_target.length() + 1 > params.buffer.size)
return -ENAMETOOLONG;
copy_to_user(params.buffer.data, link_target.characters(), link_target.length() + 1);
return link_target.length() + 1;
}
int Process::sys$chdir(const char* user_path, size_t path_length)
{
REQUIRE_PROMISE(rpath);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
auto directory_or_error = VFS::the().open_directory(path.value(), current_directory());
if (directory_or_error.is_error())
return directory_or_error.error();
m_cwd = *directory_or_error.value();
return 0;
}
int Process::sys$fchdir(int fd)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_directory())
return -ENOTDIR;
if (!description->metadata().may_execute(*this))
return -EACCES;
m_cwd = description->custody();
return 0;
}
int Process::sys$getcwd(char* buffer, ssize_t size)
{
REQUIRE_PROMISE(rpath);
if (size < 0)
return -EINVAL;
if (!validate_write(buffer, size))
return -EFAULT;
auto path = current_directory().absolute_path();
if ((size_t)size < path.length() + 1)
return -ERANGE;
copy_to_user(buffer, path.characters(), path.length() + 1);
return 0;
}
int Process::number_of_open_file_descriptors() const
{
int count = 0;
for (auto& description : m_fds) {
if (description)
++count;
}
return count;
}
int Process::sys$open(const Syscall::SC_open_params* user_params)
{
Syscall::SC_open_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
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)
REQUIRE_PROMISE(wpath);
else if (options & O_RDONLY)
REQUIRE_PROMISE(rpath);
if (options & O_CREAT)
REQUIRE_PROMISE(cpath);
// Ignore everything except permission bits.
mode &= 04777;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
#ifdef DEBUG_IO
dbg() << "sys$open(dirfd=" << dirfd << ", path=\"" << path.value() << "\", options=" << options << ", mode=" << mode << ")";
#endif
int fd = alloc_fd();
if (fd < 0)
return fd;
RefPtr<Custody> base;
if (dirfd == AT_FDCWD) {
base = current_directory();
} else {
auto base_description = file_description(dirfd);
if (!base_description)
return -EBADF;
if (!base_description->is_directory())
return -ENOTDIR;
if (!base_description->custody())
return -EINVAL;
base = base_description->custody();
}
auto result = VFS::the().open(path.value(), options, mode & ~umask(), *base);
if (result.is_error())
return result.error();
auto description = result.value();
u32 fd_flags = (options & O_CLOEXEC) ? FD_CLOEXEC : 0;
m_fds[fd].set(move(description), fd_flags);
return fd;
}
int Process::alloc_fd(int first_candidate_fd)
{
for (int i = first_candidate_fd; i < (int)m_max_open_file_descriptors; ++i) {
if (!m_fds[i])
return i;
}
return -EMFILE;
}
int Process::sys$pipe(int pipefd[2], int flags)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(pipefd))
return -EFAULT;
if (number_of_open_file_descriptors() + 2 > max_open_file_descriptors())
return -EMFILE;
// Reject flags other than O_CLOEXEC.
if ((flags & O_CLOEXEC) != flags)
return -EINVAL;
u32 fd_flags = (flags & O_CLOEXEC) ? FD_CLOEXEC : 0;
auto fifo = FIFO::create(m_uid);
int reader_fd = alloc_fd();
m_fds[reader_fd].set(fifo->open_direction(FIFO::Direction::Reader), fd_flags);
m_fds[reader_fd].description->set_readable(true);
copy_to_user(&pipefd[0], &reader_fd);
int writer_fd = alloc_fd();
m_fds[writer_fd].set(fifo->open_direction(FIFO::Direction::Writer), fd_flags);
m_fds[writer_fd].description->set_writable(true);
copy_to_user(&pipefd[1], &writer_fd);
return 0;
}
int Process::sys$killpg(int pgrp, int signum)
{
REQUIRE_PROMISE(proc);
if (signum < 1 || signum >= 32)
return -EINVAL;
if (pgrp < 0)
return -EINVAL;
return do_killpg(pgrp, signum);
}
int Process::sys$setuid(uid_t uid)
{
REQUIRE_PROMISE(id);
if (uid != m_uid && !is_superuser())
return -EPERM;
m_uid = uid;
m_euid = uid;
return 0;
}
int Process::sys$setgid(gid_t gid)
{
REQUIRE_PROMISE(id);
if (gid != m_gid && !is_superuser())
return -EPERM;
m_gid = gid;
m_egid = gid;
return 0;
}
unsigned Process::sys$alarm(unsigned seconds)
{
REQUIRE_PROMISE(stdio);
unsigned previous_alarm_remaining = 0;
if (m_alarm_deadline && m_alarm_deadline > g_uptime) {
previous_alarm_remaining = (m_alarm_deadline - g_uptime) / TimeManagement::the().ticks_per_second();
}
if (!seconds) {
m_alarm_deadline = 0;
return previous_alarm_remaining;
}
m_alarm_deadline = g_uptime + seconds * TimeManagement::the().ticks_per_second();
return previous_alarm_remaining;
}
int Process::sys$uname(utsname* buf)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(buf))
return -EFAULT;
LOCKER(*s_hostname_lock);
if (s_hostname->length() + 1 > sizeof(utsname::nodename))
return -ENAMETOOLONG;
copy_to_user(buf->sysname, "SerenityOS", 11);
copy_to_user(buf->release, "1.0-dev", 8);
copy_to_user(buf->version, "FIXME", 6);
copy_to_user(buf->machine, "i686", 5);
copy_to_user(buf->nodename, s_hostname->characters(), s_hostname->length() + 1);
return 0;
}
KResult Process::do_kill(Process& process, int signal)
{
// FIXME: Allow sending SIGCONT to everyone in the process group.
// FIXME: Should setuid processes have some special treatment here?
if (!is_superuser() && m_euid != process.m_uid && m_uid != process.m_uid)
return KResult(-EPERM);
if (process.is_ring0() && signal == SIGKILL) {
klog() << "attempted to send SIGKILL to ring 0 process " << process.name().characters() << "(" << process.pid() << ")";
return KResult(-EPERM);
}
if (signal != 0)
process.send_signal(signal, this);
return KSuccess;
}
KResult Process::do_killpg(pid_t pgrp, int signal)
{
InterruptDisabler disabler;
ASSERT(pgrp >= 0);
// Send the signal to all processes in the given group.
if (pgrp == 0) {
// Send the signal to our own pgrp.
pgrp = pgid();
}
bool group_was_empty = true;
bool any_succeeded = false;
KResult error = KSuccess;
Process::for_each_in_pgrp(pgrp, [&](auto& process) {
group_was_empty = false;
KResult res = do_kill(process, signal);
if (res.is_success())
any_succeeded = true;
else
error = res;
return IterationDecision::Continue;
});
if (group_was_empty)
return KResult(-ESRCH);
if (any_succeeded)
return KSuccess;
return error;
}
int Process::sys$kill(pid_t pid, int signal)
{
if (pid == m_pid)
REQUIRE_PROMISE(stdio);
else
REQUIRE_PROMISE(proc);
if (signal < 0 || signal >= 32)
return -EINVAL;
if (pid <= 0) {
if (pid == INT32_MIN)
return -EINVAL;
return do_killpg(-pid, signal);
}
if (pid == -1) {
// FIXME: Send to all processes.
return -ENOTIMPL;
}
if (pid == m_pid) {
if (signal == 0)
return 0;
if (!Thread::current->should_ignore_signal(signal)) {
Thread::current->send_signal(signal, this);
(void)Thread::current->block<Thread::SemiPermanentBlocker>(Thread::SemiPermanentBlocker::Reason::Signal);
}
return 0;
}
InterruptDisabler disabler;
auto* peer = Process::from_pid(pid);
if (!peer)
return -ESRCH;
return do_kill(*peer, signal);
}
int Process::sys$usleep(useconds_t usec)
{
REQUIRE_PROMISE(stdio);
if (!usec)
return 0;
u64 wakeup_time = Thread::current->sleep(usec / 1000);
if (wakeup_time > g_uptime)
return -EINTR;
return 0;
}
int Process::sys$sleep(unsigned seconds)
{
REQUIRE_PROMISE(stdio);
if (!seconds)
return 0;
u64 wakeup_time = Thread::current->sleep(seconds * TimeManagement::the().ticks_per_second());
if (wakeup_time > g_uptime) {
u32 ticks_left_until_original_wakeup_time = wakeup_time - g_uptime;
return ticks_left_until_original_wakeup_time / TimeManagement::the().ticks_per_second();
}
return 0;
}
timeval kgettimeofday()
{
return const_cast<const timeval&>(((KernelInfoPage*)s_info_page_address_for_kernel.as_ptr())->now);
}
void kgettimeofday(timeval& tv)
{
tv = kgettimeofday();
}
int Process::sys$gettimeofday(timeval* tv)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(tv))
return -EFAULT;
*tv = kgettimeofday();
return 0;
}
uid_t Process::sys$getuid()
{
REQUIRE_PROMISE(stdio);
return m_uid;
}
gid_t Process::sys$getgid()
{
REQUIRE_PROMISE(stdio);
return m_gid;
}
uid_t Process::sys$geteuid()
{
REQUIRE_PROMISE(stdio);
return m_euid;
}
gid_t Process::sys$getegid()
{
REQUIRE_PROMISE(stdio);
return m_egid;
}
pid_t Process::sys$getpid()
{
REQUIRE_PROMISE(stdio);
return m_pid;
}
pid_t Process::sys$getppid()
{
REQUIRE_PROMISE(stdio);
return m_ppid;
}
mode_t Process::sys$umask(mode_t mask)
{
REQUIRE_PROMISE(stdio);
auto old_mask = m_umask;
m_umask = mask & 0777;
return old_mask;
}
siginfo_t Process::reap(Process& process)
{
siginfo_t siginfo;
memset(&siginfo, 0, sizeof(siginfo));
siginfo.si_signo = SIGCHLD;
siginfo.si_pid = process.pid();
siginfo.si_uid = process.uid();
if (process.m_termination_signal) {
siginfo.si_status = process.m_termination_signal;
siginfo.si_code = CLD_KILLED;
} else {
siginfo.si_status = process.m_termination_status;
siginfo.si_code = CLD_EXITED;
}
{
InterruptDisabler disabler;
if (process.ppid()) {
auto* parent = Process::from_pid(process.ppid());
if (parent) {
parent->m_ticks_in_user_for_dead_children += process.m_ticks_in_user + process.m_ticks_in_user_for_dead_children;
parent->m_ticks_in_kernel_for_dead_children += process.m_ticks_in_kernel + process.m_ticks_in_kernel_for_dead_children;
}
}
#ifdef PROCESS_DEBUG
dbg() << "Reaping process " << process;
#endif
ASSERT(process.is_dead());
g_processes->remove(&process);
}
delete &process;
return siginfo;
}
KResultOr<siginfo_t> Process::do_waitid(idtype_t idtype, int id, int options)
{
if (idtype == P_PID) {
InterruptDisabler disabler;
if (idtype == P_PID && !Process::from_pid(id))
return KResult(-ECHILD);
}
if (options & WNOHANG) {
// FIXME: Figure out what WNOHANG should do with stopped children.
if (idtype == P_ALL) {
InterruptDisabler disabler;
siginfo_t siginfo;
memset(&siginfo, 0, sizeof(siginfo));
for_each_child([&siginfo](Process& process) {
if (process.is_dead())
siginfo = reap(process);
return IterationDecision::Continue;
});
return siginfo;
} else if (idtype == P_PID) {
InterruptDisabler disabler;
auto* waitee_process = Process::from_pid(id);
if (!waitee_process)
return KResult(-ECHILD);
if (waitee_process->is_dead())
return reap(*waitee_process);
} else {
// FIXME: Implement other PID specs.
return KResult(-EINVAL);
}
}
pid_t waitee_pid;
// FIXME: WaitBlocker should support idtype/id specs directly.
if (idtype == P_ALL) {
waitee_pid = -1;
} else if (idtype == P_PID) {
waitee_pid = id;
} else {
// FIXME: Implement other PID specs.
return KResult(-EINVAL);
}
if (Thread::current->block<Thread::WaitBlocker>(options, waitee_pid) != Thread::BlockResult::WokeNormally)
return KResult(-EINTR);
InterruptDisabler disabler;
// NOTE: If waitee was -1, m_waitee_pid will have been filled in by the scheduler.
Process* waitee_process = Process::from_pid(waitee_pid);
if (!waitee_process)
return KResult(-ECHILD);
ASSERT(waitee_process);
if (waitee_process->is_dead()) {
return reap(*waitee_process);
} else {
auto* waitee_thread = Thread::from_tid(waitee_pid);
if (!waitee_thread)
return KResult(-ECHILD);
ASSERT(waitee_thread->state() == Thread::State::Stopped);
siginfo_t siginfo;
memset(&siginfo, 0, sizeof(siginfo));
siginfo.si_signo = SIGCHLD;
siginfo.si_pid = waitee_process->pid();
siginfo.si_uid = waitee_process->uid();
siginfo.si_status = CLD_STOPPED;
siginfo.si_code = waitee_thread->m_stop_signal;
return siginfo;
}
}
pid_t Process::sys$waitid(const Syscall::SC_waitid_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_waitid_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!validate_write_typed(params.infop))
return -EFAULT;
#ifdef PROCESS_DEBUG
dbg() << "sys$waitid(" << params.idtype << ", " << params.id << ", " << params.infop << ", " << params.options << ")";
#endif
auto siginfo_or_error = do_waitid(static_cast<idtype_t>(params.idtype), params.id, params.options);
if (siginfo_or_error.is_error())
return siginfo_or_error.error();
// While we waited, the process lock was dropped. This gave other threads
// the opportunity to mess with the memory. For example, it could free the
// region, and map it to a region to which it has no write permissions.
// Therefore, we need to re-validate the pointer.
if (!validate_write_typed(params.infop))
return -EFAULT;
copy_to_user(params.infop, &siginfo_or_error.value());
return 0;
}
bool Process::validate_read_from_kernel(VirtualAddress vaddr, size_t size) const
{
if (vaddr.is_null())
return false;
return MM.validate_kernel_read(*this, vaddr, size);
}
bool Process::validate_read(const void* address, size_t size) const
{
if (!size)
return false;
return MM.validate_user_read(*this, VirtualAddress(address), size);
}
bool Process::validate_write(void* address, size_t size) const
{
if (!size)
return false;
return MM.validate_user_write(*this, VirtualAddress(address), size);
}
pid_t Process::sys$getsid(pid_t pid)
{
REQUIRE_PROMISE(stdio);
if (pid == 0)
return m_sid;
InterruptDisabler disabler;
auto* process = Process::from_pid(pid);
if (!process)
return -ESRCH;
if (m_sid != process->m_sid)
return -EPERM;
return process->m_sid;
}
pid_t Process::sys$setsid()
{
REQUIRE_PROMISE(proc);
InterruptDisabler disabler;
bool found_process_with_same_pgid_as_my_pid = false;
Process::for_each_in_pgrp(pid(), [&](auto&) {
found_process_with_same_pgid_as_my_pid = true;
return IterationDecision::Break;
});
if (found_process_with_same_pgid_as_my_pid)
return -EPERM;
m_sid = m_pid;
m_pgid = m_pid;
m_tty = nullptr;
return m_sid;
}
pid_t Process::sys$getpgid(pid_t pid)
{
REQUIRE_PROMISE(stdio);
if (pid == 0)
return m_pgid;
InterruptDisabler disabler; // FIXME: Use a ProcessHandle
auto* process = Process::from_pid(pid);
if (!process)
return -ESRCH;
return process->m_pgid;
}
pid_t Process::sys$getpgrp()
{
REQUIRE_PROMISE(stdio);
return m_pgid;
}
static pid_t get_sid_from_pgid(pid_t pgid)
{
InterruptDisabler disabler;
auto* group_leader = Process::from_pid(pgid);
if (!group_leader)
return -1;
return group_leader->sid();
}
int Process::sys$setpgid(pid_t specified_pid, pid_t specified_pgid)
{
REQUIRE_PROMISE(proc);
InterruptDisabler disabler; // FIXME: Use a ProcessHandle
pid_t pid = specified_pid ? specified_pid : m_pid;
if (specified_pgid < 0) {
// The value of the pgid argument is less than 0, or is not a value supported by the implementation.
return -EINVAL;
}
auto* process = Process::from_pid(pid);
if (!process)
return -ESRCH;
if (process != this && process->ppid() != m_pid) {
// The value of the pid argument does not match the process ID
// of the calling process or of a child process of the calling process.
return -ESRCH;
}
if (process->pid() == process->sid()) {
// The process indicated by the pid argument is a session leader.
return -EPERM;
}
if (process->ppid() == m_pid && process->sid() != sid()) {
// The value of the pid argument matches the process ID of a child
// process of the calling process and the child process is not in
// the same session as the calling process.
return -EPERM;
}
pid_t new_pgid = specified_pgid ? specified_pgid : process->m_pid;
pid_t current_sid = get_sid_from_pgid(process->m_pgid);
pid_t new_sid = get_sid_from_pgid(new_pgid);
if (current_sid != new_sid) {
// Can't move a process between sessions.
return -EPERM;
}
// FIXME: There are more EPERM conditions to check for here..
process->m_pgid = new_pgid;
return 0;
}
int Process::sys$ioctl(int fd, unsigned request, unsigned arg)
{
auto description = file_description(fd);
if (!description)
return -EBADF;
SmapDisabler disabler;
return description->file().ioctl(*description, request, arg);
}
int Process::sys$getdtablesize()
{
REQUIRE_PROMISE(stdio);
return m_max_open_file_descriptors;
}
int Process::sys$dup(int old_fd)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(old_fd);
if (!description)
return -EBADF;
int new_fd = alloc_fd();
if (new_fd < 0)
return new_fd;
m_fds[new_fd].set(*description);
return new_fd;
}
int Process::sys$dup2(int old_fd, int new_fd)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(old_fd);
if (!description)
return -EBADF;
if (new_fd < 0 || new_fd >= m_max_open_file_descriptors)
return -EINVAL;
m_fds[new_fd].set(*description);
return new_fd;
}
int Process::sys$sigprocmask(int how, const sigset_t* set, sigset_t* old_set)
{
REQUIRE_PROMISE(stdio);
if (old_set) {
if (!validate_write_typed(old_set))
return -EFAULT;
copy_to_user(old_set, &Thread::current->m_signal_mask);
}
if (set) {
if (!validate_read_typed(set))
return -EFAULT;
sigset_t set_value;
copy_from_user(&set_value, set);
switch (how) {
case SIG_BLOCK:
Thread::current->m_signal_mask &= ~set_value;
break;
case SIG_UNBLOCK:
Thread::current->m_signal_mask |= set_value;
break;
case SIG_SETMASK:
Thread::current->m_signal_mask = set_value;
break;
default:
return -EINVAL;
}
}
return 0;
}
int Process::sys$sigpending(sigset_t* set)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(set))
return -EFAULT;
copy_to_user(set, &Thread::current->m_pending_signals);
return 0;
}
int Process::sys$sigaction(int signum, const sigaction* act, sigaction* old_act)
{
REQUIRE_PROMISE(stdio);
if (signum < 1 || signum >= 32 || signum == SIGKILL || signum == SIGSTOP)
return -EINVAL;
if (!validate_read_typed(act))
return -EFAULT;
InterruptDisabler disabler; // FIXME: This should use a narrower lock. Maybe a way to ignore signals temporarily?
auto& action = Thread::current->m_signal_action_data[signum];
if (old_act) {
if (!validate_write_typed(old_act))
return -EFAULT;
copy_to_user(&old_act->sa_flags, &action.flags);
copy_to_user(&old_act->sa_sigaction, &action.handler_or_sigaction, sizeof(action.handler_or_sigaction));
}
copy_from_user(&action.flags, &act->sa_flags);
copy_from_user(&action.handler_or_sigaction, &act->sa_sigaction, sizeof(action.handler_or_sigaction));
return 0;
}
int Process::sys$getgroups(ssize_t count, gid_t* user_gids)
{
REQUIRE_PROMISE(stdio);
if (count < 0)
return -EINVAL;
if (!count)
return m_extra_gids.size();
if (count != (int)m_extra_gids.size())
return -EINVAL;
if (!validate_write_typed(user_gids, m_extra_gids.size()))
return -EFAULT;
Vector<gid_t> gids;
for (auto gid : m_extra_gids)
gids.append(gid);
copy_to_user(user_gids, gids.data(), sizeof(gid_t) * count);
return 0;
}
int Process::sys$setgroups(ssize_t count, const gid_t* user_gids)
{
REQUIRE_PROMISE(id);
if (count < 0)
return -EINVAL;
if (!is_superuser())
return -EPERM;
if (count && !validate_read(user_gids, count))
return -EFAULT;
Vector<gid_t> gids;
gids.resize(count);
copy_from_user(gids.data(), user_gids, sizeof(gid_t) * count);
HashTable<gid_t> unique_extra_gids;
for (auto& gid : gids) {
if (gid != m_gid)
unique_extra_gids.set(gid);
}
m_extra_gids.resize(unique_extra_gids.size());
size_t i = 0;
for (auto& gid : unique_extra_gids) {
if (gid == m_gid)
continue;
m_extra_gids[i++] = gid;
}
return 0;
}
int Process::sys$mkdir(const char* user_path, size_t path_length, mode_t mode)
{
REQUIRE_PROMISE(cpath);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
return VFS::the().mkdir(path.value(), mode & ~umask(), current_directory());
}
int Process::sys$realpath(const Syscall::SC_realpath_params* user_params)
{
REQUIRE_PROMISE(rpath);
Syscall::SC_realpath_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!validate_write(params.buffer.data, params.buffer.size))
return -EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
auto custody_or_error = VFS::the().resolve_path(path.value(), current_directory());
if (custody_or_error.is_error())
return custody_or_error.error();
auto& custody = custody_or_error.value();
auto absolute_path = custody->absolute_path();
if (absolute_path.length() + 1 > params.buffer.size)
return -ENAMETOOLONG;
copy_to_user(params.buffer.data, absolute_path.characters(), absolute_path.length() + 1);
return 0;
};
clock_t Process::sys$times(tms* times)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(times))
return -EFAULT;
copy_to_user(×->tms_utime, &m_ticks_in_user);
copy_to_user(×->tms_stime, &m_ticks_in_kernel);
copy_to_user(×->tms_cutime, &m_ticks_in_user_for_dead_children);
copy_to_user(×->tms_cstime, &m_ticks_in_kernel_for_dead_children);
return g_uptime & 0x7fffffff;
}
int Process::sys$select(const Syscall::SC_select_params* params)
{
REQUIRE_PROMISE(stdio);
// FIXME: Return -EINVAL if timeout is invalid.
if (!validate_read_typed(params))
return -EFAULT;
SmapDisabler disabler;
int nfds = params->nfds;
fd_set* readfds = params->readfds;
fd_set* writefds = params->writefds;
fd_set* exceptfds = params->exceptfds;
timeval* timeout = params->timeout;
if (writefds && !validate_write_typed(writefds))
return -EFAULT;
if (readfds && !validate_write_typed(readfds))
return -EFAULT;
if (exceptfds && !validate_write_typed(exceptfds))
return -EFAULT;
if (timeout && !validate_read_typed(timeout))
return -EFAULT;
if (nfds < 0)
return -EINVAL;
timeval computed_timeout;
bool select_has_timeout = false;
if (timeout && (timeout->tv_sec || timeout->tv_usec)) {
timeval_add(Scheduler::time_since_boot(), *timeout, computed_timeout);
select_has_timeout = true;
}
Thread::SelectBlocker::FDVector rfds;
Thread::SelectBlocker::FDVector wfds;
Thread::SelectBlocker::FDVector efds;
auto transfer_fds = [&](auto* fds, auto& vector) -> int {
vector.clear_with_capacity();
if (!fds)
return 0;
for (int fd = 0; fd < nfds; ++fd) {
if (FD_ISSET(fd, fds)) {
if (!file_description(fd)) {
dbg() << "sys$select: Bad fd number " << fd;
return -EBADF;
}
vector.append(fd);
}
}
return 0;
};
if (int error = transfer_fds(writefds, wfds))
return error;
if (int error = transfer_fds(readfds, rfds))
return error;
if (int error = transfer_fds(exceptfds, efds))
return error;
#if defined(DEBUG_IO) || defined(DEBUG_POLL_SELECT)
dbg() << "selecting on (read:" << rfds.size() << ", write:" << wfds.size() << "), timeout=" << timeout;
#endif
if (!timeout || select_has_timeout) {
if (Thread::current->block<Thread::SelectBlocker>(computed_timeout, select_has_timeout, rfds, wfds, efds) != Thread::BlockResult::WokeNormally)
return -EINTR;
// While we blocked, the process lock was dropped. This gave other threads
// the opportunity to mess with the memory. For example, it could free the
// region, and map it to a region to which it has no write permissions.
// Therefore, we need to re-validate all pointers.
if (writefds && !validate_write_typed(writefds))
return -EFAULT;
if (readfds && !validate_write_typed(readfds))
return -EFAULT;
// See the fixme below.
if (exceptfds && !validate_write_typed(exceptfds))
return -EFAULT;
}
int marked_fd_count = 0;
auto mark_fds = [&](auto* fds, auto& vector, auto should_mark) {
if (!fds)
return;
FD_ZERO(fds);
for (int fd : vector) {
if (auto description = file_description(fd); description && should_mark(*description)) {
FD_SET(fd, fds);
++marked_fd_count;
}
}
};
mark_fds(readfds, rfds, [](auto& description) { return description.can_read(); });
mark_fds(writefds, wfds, [](auto& description) { return description.can_write(); });
// FIXME: We should also mark exceptfds as appropriate.
return marked_fd_count;
}
int Process::sys$poll(pollfd* fds, int nfds, int timeout)
{
REQUIRE_PROMISE(stdio);
if (!validate_read_typed(fds))
return -EFAULT;
SmapDisabler disabler;
Thread::SelectBlocker::FDVector rfds;
Thread::SelectBlocker::FDVector wfds;
for (int i = 0; i < nfds; ++i) {
if (fds[i].events & POLLIN)
rfds.append(fds[i].fd);
if (fds[i].events & POLLOUT)
wfds.append(fds[i].fd);
}
timeval actual_timeout;
bool has_timeout = false;
if (timeout >= 0) {
// poll is in ms, we want s/us.
struct timeval tvtimeout;
tvtimeout.tv_sec = 0;
while (timeout >= 1000) {
tvtimeout.tv_sec += 1;
timeout -= 1000;
}
tvtimeout.tv_usec = timeout * 1000;
timeval_add(Scheduler::time_since_boot(), tvtimeout, actual_timeout);
has_timeout = true;
}
#if defined(DEBUG_IO) || defined(DEBUG_POLL_SELECT)
dbg() << "polling on (read:" << rfds.size() << ", write:" << wfds.size() << "), timeout=" << timeout;
#endif
if (has_timeout || timeout < 0) {
if (Thread::current->block<Thread::SelectBlocker>(actual_timeout, has_timeout, rfds, wfds, Thread::SelectBlocker::FDVector()) != Thread::BlockResult::WokeNormally)
return -EINTR;
}
int fds_with_revents = 0;
for (int i = 0; i < nfds; ++i) {
auto description = file_description(fds[i].fd);
if (!description) {
fds[i].revents = POLLNVAL;
continue;
}
fds[i].revents = 0;
if (fds[i].events & POLLIN && description->can_read())
fds[i].revents |= POLLIN;
if (fds[i].events & POLLOUT && description->can_write())
fds[i].revents |= POLLOUT;
if (fds[i].revents)
++fds_with_revents;
}
return fds_with_revents;
}
Custody& Process::current_directory()
{
if (!m_cwd)
m_cwd = VFS::the().root_custody();
return *m_cwd;
}
int Process::sys$link(const Syscall::SC_link_params* user_params)
{
REQUIRE_PROMISE(cpath);
Syscall::SC_link_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
auto old_path = validate_and_copy_string_from_user(params.old_path);
auto new_path = validate_and_copy_string_from_user(params.new_path);
if (old_path.is_null() || new_path.is_null())
return -EFAULT;
return VFS::the().link(old_path, new_path, current_directory());
}
int Process::sys$unlink(const char* user_path, size_t path_length)
{
REQUIRE_PROMISE(cpath);
if (!validate_read(user_path, path_length))
return -EFAULT;
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
return VFS::the().unlink(path.value(), current_directory());
}
int Process::sys$symlink(const Syscall::SC_symlink_params* user_params)
{
REQUIRE_PROMISE(cpath);
Syscall::SC_symlink_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
auto target = get_syscall_path_argument(params.target);
if (target.is_error())
return target.error();
auto linkpath = get_syscall_path_argument(params.linkpath);
if (linkpath.is_error())
return linkpath.error();
return VFS::the().symlink(target.value(), linkpath.value(), current_directory());
}
KResultOr<String> Process::get_syscall_path_argument(const char* user_path, size_t path_length) const
{
if (path_length == 0)
return KResult(-EINVAL);
if (path_length > PATH_MAX)
return KResult(-ENAMETOOLONG);
if (!validate_read(user_path, path_length))
return KResult(-EFAULT);
return copy_string_from_user(user_path, path_length);
}
KResultOr<String> Process::get_syscall_path_argument(const Syscall::StringArgument& path) const
{
return get_syscall_path_argument(path.characters, path.length);
}
int Process::sys$rmdir(const char* user_path, size_t path_length)
{
REQUIRE_PROMISE(cpath);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
return VFS::the().rmdir(path.value(), current_directory());
}
int Process::sys$chmod(const char* user_path, size_t path_length, mode_t mode)
{
REQUIRE_PROMISE(fattr);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
return VFS::the().chmod(path.value(), mode, current_directory());
}
int Process::sys$fchmod(int fd, mode_t mode)
{
REQUIRE_PROMISE(fattr);
auto description = file_description(fd);
if (!description)
return -EBADF;
return description->chmod(mode);
}
int Process::sys$fchown(int fd, uid_t uid, gid_t gid)
{
REQUIRE_PROMISE(chown);
auto description = file_description(fd);
if (!description)
return -EBADF;
return description->chown(uid, gid);
}
int Process::sys$chown(const Syscall::SC_chown_params* user_params)
{
REQUIRE_PROMISE(chown);
Syscall::SC_chown_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
return VFS::the().chown(path.value(), params.uid, params.gid, current_directory());
}
void Process::finalize()
{
ASSERT(Thread::current == g_finalizer);
#ifdef PROCESS_DEBUG
dbg() << "Finalizing process " << *this;
#endif
if (m_perf_event_buffer) {
auto description_or_error = VFS::the().open(String::format("perfcore.%d", m_pid), O_CREAT | O_EXCL, 0400, current_directory(), UidAndGid { m_uid, m_gid });
if (!description_or_error.is_error()) {
auto& description = description_or_error.value();
auto json = m_perf_event_buffer->to_json(m_pid, m_executable ? m_executable->absolute_path() : "");
description->write(json.data(), json.size());
}
}
m_fds.clear();
m_tty = nullptr;
m_executable = nullptr;
m_cwd = nullptr;
m_root_directory = nullptr;
m_root_directory_relative_to_global_root = nullptr;
disown_all_shared_buffers();
{
InterruptDisabler disabler;
if (auto* parent_thread = Thread::from_tid(m_ppid)) {
if (parent_thread->m_signal_action_data[SIGCHLD].flags & SA_NOCLDWAIT) {
// NOTE: If the parent doesn't care about this process, let it go.
m_ppid = 0;
} else {
parent_thread->send_signal(SIGCHLD, this);
}
}
}
m_regions.clear();
m_dead = true;
}
void Process::die()
{
// Let go of the TTY, otherwise a slave PTY may keep the master PTY from
// getting an EOF when the last process using the slave PTY dies.
// If the master PTY owner relies on an EOF to know when to wait() on a
// slave owner, we have to allow the PTY pair to be torn down.
m_tty = nullptr;
if (m_tracer)
m_tracer->set_dead();
kill_all_threads();
}
size_t Process::amount_dirty_private() const
{
// FIXME: This gets a bit more complicated for Regions sharing the same underlying VMObject.
// The main issue I'm thinking of is when the VMObject has physical pages that none of the Regions are mapping.
// That's probably a situation that needs to be looked at in general.
size_t amount = 0;
for (auto& region : m_regions) {
if (!region.is_shared())
amount += region.amount_dirty();
}
return amount;
}
size_t Process::amount_clean_inode() const
{
HashTable<const InodeVMObject*> vmobjects;
for (auto& region : m_regions) {
if (region.vmobject().is_inode())
vmobjects.set(&static_cast<const InodeVMObject&>(region.vmobject()));
}
size_t amount = 0;
for (auto& vmobject : vmobjects)
amount += vmobject->amount_clean();
return amount;
}
size_t Process::amount_virtual() const
{
size_t amount = 0;
for (auto& region : m_regions) {
amount += region.size();
}
return amount;
}
size_t Process::amount_resident() const
{
// FIXME: This will double count if multiple regions use the same physical page.
size_t amount = 0;
for (auto& region : m_regions) {
amount += region.amount_resident();
}
return amount;
}
size_t Process::amount_shared() const
{
// FIXME: This will double count if multiple regions use the same physical page.
// FIXME: It doesn't work at the moment, since it relies on PhysicalPage ref counts,
// and each PhysicalPage is only reffed by its VMObject. This needs to be refactored
// so that every Region contributes +1 ref to each of its PhysicalPages.
size_t amount = 0;
for (auto& region : m_regions) {
amount += region.amount_shared();
}
return amount;
}
size_t Process::amount_purgeable_volatile() const
{
size_t amount = 0;
for (auto& region : m_regions) {
if (region.vmobject().is_purgeable() && static_cast<const PurgeableVMObject&>(region.vmobject()).is_volatile())
amount += region.amount_resident();
}
return amount;
}
size_t Process::amount_purgeable_nonvolatile() const
{
size_t amount = 0;
for (auto& region : m_regions) {
if (region.vmobject().is_purgeable() && !static_cast<const PurgeableVMObject&>(region.vmobject()).is_volatile())
amount += region.amount_resident();
}
return amount;
}
#define REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(domain) \
do { \
if (domain == AF_INET) \
REQUIRE_PROMISE(inet); \
else if (domain == AF_LOCAL) \
REQUIRE_PROMISE(unix); \
} while (0)
int Process::sys$socket(int domain, int type, int protocol)
{
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(domain);
if ((type & SOCK_TYPE_MASK) == SOCK_RAW && !is_superuser())
return -EACCES;
int fd = alloc_fd();
if (fd < 0)
return fd;
auto result = Socket::create(domain, type, protocol);
if (result.is_error())
return result.error();
auto description = FileDescription::create(*result.value());
description->set_readable(true);
description->set_writable(true);
unsigned flags = 0;
if (type & SOCK_CLOEXEC)
flags |= FD_CLOEXEC;
if (type & SOCK_NONBLOCK)
description->set_blocking(false);
m_fds[fd].set(move(description), flags);
return fd;
}
int Process::sys$bind(int sockfd, const sockaddr* address, socklen_t address_length)
{
if (!validate_read(address, address_length))
return -EFAULT;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
return socket.bind(address, address_length);
}
int Process::sys$listen(int sockfd, int backlog)
{
if (backlog < 0)
return -EINVAL;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
if (socket.is_connected())
return -EINVAL;
return socket.listen(backlog);
}
int Process::sys$accept(int accepting_socket_fd, sockaddr* user_address, socklen_t* user_address_size)
{
REQUIRE_PROMISE(accept);
if (!validate_write_typed(user_address_size))
return -EFAULT;
socklen_t address_size = 0;
copy_from_user(&address_size, user_address_size);
if (!validate_write(user_address, address_size))
return -EFAULT;
int accepted_socket_fd = alloc_fd();
if (accepted_socket_fd < 0)
return accepted_socket_fd;
auto accepting_socket_description = file_description(accepting_socket_fd);
if (!accepting_socket_description)
return -EBADF;
if (!accepting_socket_description->is_socket())
return -ENOTSOCK;
auto& socket = *accepting_socket_description->socket();
if (!socket.can_accept()) {
if (accepting_socket_description->is_blocking()) {
if (Thread::current->block<Thread::AcceptBlocker>(*accepting_socket_description) != Thread::BlockResult::WokeNormally)
return -EINTR;
} else {
return -EAGAIN;
}
}
auto accepted_socket = socket.accept();
ASSERT(accepted_socket);
u8 address_buffer[sizeof(sockaddr_un)];
address_size = min(sizeof(sockaddr_un), static_cast<size_t>(address_size));
accepted_socket->get_peer_address((sockaddr*)address_buffer, &address_size);
copy_to_user(user_address, address_buffer, address_size);
copy_to_user(user_address_size, &address_size);
auto accepted_socket_description = FileDescription::create(*accepted_socket);
accepted_socket_description->set_readable(true);
accepted_socket_description->set_writable(true);
// NOTE: The accepted socket inherits fd flags from the accepting socket.
// I'm not sure if this matches other systems but it makes sense to me.
accepted_socket_description->set_blocking(accepting_socket_description->is_blocking());
m_fds[accepted_socket_fd].set(move(accepted_socket_description), m_fds[accepting_socket_fd].flags);
// NOTE: Moving this state to Completed is what causes connect() to unblock on the client side.
accepted_socket->set_setup_state(Socket::SetupState::Completed);
return accepted_socket_fd;
}
int Process::sys$connect(int sockfd, const sockaddr* user_address, socklen_t user_address_size)
{
if (!validate_read(user_address, user_address_size))
return -EFAULT;
int fd = alloc_fd();
if (fd < 0)
return fd;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
u8 address[sizeof(sockaddr_un)];
size_t address_size = min(sizeof(address), static_cast<size_t>(user_address_size));
copy_from_user(address, user_address, address_size);
return socket.connect(*description, (const sockaddr*)address, address_size, description->is_blocking() ? ShouldBlock::Yes : ShouldBlock::No);
}
int Process::sys$shutdown(int sockfd, int how)
{
REQUIRE_PROMISE(stdio);
if (how & ~SHUT_RDWR)
return -EINVAL;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
return socket.shutdown(how);
}
ssize_t Process::sys$sendto(const Syscall::SC_sendto_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_sendto_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
int flags = params.flags;
const sockaddr* addr = params.addr;
socklen_t addr_length = params.addr_length;
if (!validate(params.data))
return -EFAULT;
if (addr && !validate_read(addr, addr_length))
return -EFAULT;
auto description = file_description(params.sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
if (socket.is_shut_down_for_writing())
return -EPIPE;
SmapDisabler disabler;
return socket.sendto(*description, params.data.data, params.data.size, flags, addr, addr_length);
}
ssize_t Process::sys$recvfrom(const Syscall::SC_recvfrom_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_recvfrom_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
int flags = params.flags;
sockaddr* addr = params.addr;
socklen_t* addr_length = params.addr_length;
SmapDisabler disabler;
if (!validate(params.buffer))
return -EFAULT;
if (addr_length) {
if (!validate_write_typed(addr_length))
return -EFAULT;
if (!validate_write(addr, *addr_length))
return -EFAULT;
} else if (addr) {
return -EINVAL;
}
auto description = file_description(params.sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
if (socket.is_shut_down_for_reading())
return 0;
bool original_blocking = description->is_blocking();
if (flags & MSG_DONTWAIT)
description->set_blocking(false);
auto nrecv = socket.recvfrom(*description, params.buffer.data, params.buffer.size, flags, addr, addr_length);
if (flags & MSG_DONTWAIT)
description->set_blocking(original_blocking);
return nrecv;
}
template<bool sockname, typename Params>
int Process::get_sock_or_peer_name(const Params& params)
{
socklen_t addrlen_value;
if (!validate_read_and_copy_typed(&addrlen_value, params.addrlen))
return -EFAULT;
if (addrlen_value <= 0)
return -EINVAL;
if (!validate_write(params.addr, addrlen_value))
return -EFAULT;
if (!validate_write_typed(params.addrlen))
return -EFAULT;
auto description = file_description(params.sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
u8 address_buffer[sizeof(sockaddr_un)];
addrlen_value = min(sizeof(sockaddr_un), static_cast<size_t>(addrlen_value));
if constexpr (sockname)
socket.get_local_address((sockaddr*)address_buffer, &addrlen_value);
else
socket.get_peer_address((sockaddr*)address_buffer, &addrlen_value);
copy_to_user(params.addr, address_buffer, addrlen_value);
copy_to_user(params.addrlen, &addrlen_value);
return 0;
}
int Process::sys$getsockname(const Syscall::SC_getsockname_params* user_params)
{
Syscall::SC_getsockname_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
return get_sock_or_peer_name<true>(params);
}
int Process::sys$getpeername(const Syscall::SC_getpeername_params* user_params)
{
Syscall::SC_getpeername_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
return get_sock_or_peer_name<false>(params);
}
int Process::sys$sched_setparam(int tid, const struct sched_param* param)
{
REQUIRE_PROMISE(proc);
if (!validate_read_typed(param))
return -EFAULT;
int desired_priority;
copy_from_user(&desired_priority, ¶m->sched_priority);
InterruptDisabler disabler;
auto* peer = Thread::current;
if (tid != 0)
peer = Thread::from_tid(tid);
if (!peer)
return -ESRCH;
if (!is_superuser() && m_euid != peer->process().m_uid && m_uid != peer->process().m_uid)
return -EPERM;
if (desired_priority < THREAD_PRIORITY_MIN || desired_priority > THREAD_PRIORITY_MAX)
return -EINVAL;
peer->set_priority((u32)desired_priority);
return 0;
}
int Process::sys$sched_getparam(pid_t pid, struct sched_param* param)
{
REQUIRE_PROMISE(proc);
if (!validate_write_typed(param))
return -EFAULT;
InterruptDisabler disabler;
auto* peer = Thread::current;
if (pid != 0)
peer = Thread::from_tid(pid);
if (!peer)
return -ESRCH;
if (!is_superuser() && m_euid != peer->process().m_uid && m_uid != peer->process().m_uid)
return -EPERM;
int priority = peer->priority();
copy_to_user(¶m->sched_priority, &priority);
return 0;
}
int Process::sys$getsockopt(const Syscall::SC_getsockopt_params* params)
{
if (!validate_read_typed(params))
return -EFAULT;
SmapDisabler disabler;
int sockfd = params->sockfd;
int level = params->level;
int option = params->option;
void* value = params->value;
socklen_t* value_size = params->value_size;
if (!validate_write_typed(value_size))
return -EFAULT;
if (!validate_write(value, *value_size))
return -EFAULT;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
if (has_promised(Pledge::accept) && socket.is_local() && level == SOL_SOCKET && option == SO_PEERCRED) {
// We make an exception for SOL_SOCKET::SO_PEERCRED on local sockets if you've pledged "accept"
} else {
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
}
return socket.getsockopt(*description, level, option, value, value_size);
}
int Process::sys$setsockopt(const Syscall::SC_setsockopt_params* params)
{
if (!validate_read_typed(params))
return -EFAULT;
SmapDisabler disabler;
int sockfd = params->sockfd;
int level = params->level;
int option = params->option;
const void* value = params->value;
socklen_t value_size = params->value_size;
if (!validate_read(value, value_size))
return -EFAULT;
auto description = file_description(sockfd);
if (!description)
return -EBADF;
if (!description->is_socket())
return -ENOTSOCK;
auto& socket = *description->socket();
REQUIRE_PROMISE_FOR_SOCKET_DOMAIN(socket.domain());
return socket.setsockopt(level, option, value, value_size);
}
void Process::disown_all_shared_buffers()
{
LOCKER(shared_buffers().lock());
Vector<SharedBuffer*, 32> buffers_to_disown;
for (auto& it : shared_buffers().resource())
buffers_to_disown.append(it.value.ptr());
for (auto* shared_buffer : buffers_to_disown)
shared_buffer->disown(m_pid);
}
int Process::sys$shbuf_create(int size, void** buffer)
{
REQUIRE_PROMISE(shared_buffer);
if (!size || size < 0)
return -EINVAL;
size = PAGE_ROUND_UP(size);
if (!validate_write_typed(buffer))
return -EFAULT;
LOCKER(shared_buffers().lock());
static int s_next_shbuf_id;
int shbuf_id = ++s_next_shbuf_id;
auto shared_buffer = make<SharedBuffer>(shbuf_id, size);
shared_buffer->share_with(m_pid);
void* address = shared_buffer->ref_for_process_and_get_address(*this);
copy_to_user(buffer, &address);
ASSERT((int)shared_buffer->size() >= size);
#ifdef SHARED_BUFFER_DEBUG
klog() << "Created shared buffer " << shbuf_id << " @ " << buffer << " (" << size << " bytes, vmobject is " << shared_buffer->size() << ")";
#endif
shared_buffers().resource().set(shbuf_id, move(shared_buffer));
return shbuf_id;
}
int Process::sys$shbuf_allow_pid(int shbuf_id, pid_t peer_pid)
{
REQUIRE_PROMISE(shared_buffer);
if (!peer_pid || peer_pid < 0 || peer_pid == m_pid)
return -EINVAL;
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
{
InterruptDisabler disabler;
auto* peer = Process::from_pid(peer_pid);
if (!peer)
return -ESRCH;
}
shared_buffer.share_with(peer_pid);
return 0;
}
int Process::sys$shbuf_allow_all(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
shared_buffer.share_globally();
return 0;
}
int Process::sys$shbuf_release(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Releasing shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
shared_buffer.deref_for_process(*this);
return 0;
}
void* Process::sys$shbuf_get(int shbuf_id, size_t* user_size)
{
REQUIRE_PROMISE(shared_buffer);
if (user_size && !validate_write_typed(user_size))
return (void*)-EFAULT;
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return (void*)-EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return (void*)-EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Retaining shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
if (user_size) {
size_t size = shared_buffer.size();
copy_to_user(user_size, &size);
}
return shared_buffer.ref_for_process_and_get_address(*this);
}
int Process::sys$shbuf_seal(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Sealing shared buffer " << shbuf_id;
#endif
shared_buffer.seal();
return 0;
}
int Process::sys$shbuf_set_volatile(int shbuf_id, bool state)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Set shared buffer " << shbuf_id << " volatile: " << state;
#endif
if (!state) {
bool was_purged = shared_buffer.vmobject().was_purged();
shared_buffer.vmobject().set_volatile(state);
shared_buffer.vmobject().set_was_purged(false);
return was_purged ? 1 : 0;
}
shared_buffer.vmobject().set_volatile(true);
return 0;
}
void Process::terminate_due_to_signal(u8 signal)
{
ASSERT_INTERRUPTS_DISABLED();
ASSERT(signal < 32);
dbg() << "Terminating due to signal " << signal;
m_termination_status = 0;
m_termination_signal = signal;
die();
}
void Process::send_signal(u8 signal, Process* sender)
{
InterruptDisabler disabler;
if (!m_thread_count)
return;
auto* thread = Thread::from_tid(m_pid);
if (!thread)
thread = &any_thread();
thread->send_signal(signal, sender);
}
int Process::sys$create_thread(void* (*entry)(void*), void* argument, const Syscall::SC_create_thread_params* user_params)
{
REQUIRE_PROMISE(thread);
if (!validate_read((const void*)entry, sizeof(void*)))
return -EFAULT;
Syscall::SC_create_thread_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
unsigned detach_state = params.m_detach_state;
int schedule_priority = params.m_schedule_priority;
void* stack_location = params.m_stack_location;
unsigned stack_size = params.m_stack_size;
if (!validate_write(stack_location, stack_size))
return -EFAULT;
u32 user_stack_address = reinterpret_cast<u32>(stack_location) + stack_size;
if (!MM.validate_user_stack(*this, VirtualAddress(user_stack_address - 4)))
return -EFAULT;
// FIXME: return EAGAIN if Thread::all_threads().size() is greater than PTHREAD_THREADS_MAX
int requested_thread_priority = schedule_priority;
if (requested_thread_priority < THREAD_PRIORITY_MIN || requested_thread_priority > THREAD_PRIORITY_MAX)
return -EINVAL;
bool is_thread_joinable = (0 == detach_state);
// FIXME: Do something with guard pages?
auto* thread = new Thread(*this);
// We know this thread is not the main_thread,
// So give it a unique name until the user calls $set_thread_name on it
// length + 4 to give space for our extra junk at the end
StringBuilder builder(m_name.length() + 4);
builder.append(m_name);
builder.appendf("[%d]", thread->tid());
thread->set_name(builder.to_string());
thread->set_priority(requested_thread_priority);
thread->set_joinable(is_thread_joinable);
auto& tss = thread->tss();
tss.eip = (FlatPtr)entry;
tss.eflags = 0x0202;
tss.cr3 = page_directory().cr3();
tss.esp = user_stack_address;
// NOTE: The stack needs to be 16-byte aligned.
thread->push_value_on_stack((FlatPtr)argument);
thread->push_value_on_stack(0);
thread->make_thread_specific_region({});
thread->set_state(Thread::State::Runnable);
return thread->tid();
}
void Process::sys$exit_thread(void* exit_value)
{
REQUIRE_PROMISE(thread);
cli();
Thread::current->m_exit_value = exit_value;
Thread::current->set_should_die();
big_lock().force_unlock_if_locked();
Thread::current->die_if_needed();
ASSERT_NOT_REACHED();
}
int Process::sys$detach_thread(int tid)
{
REQUIRE_PROMISE(thread);
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread || thread->pid() != pid())
return -ESRCH;
if (!thread->is_joinable())
return -EINVAL;
thread->set_joinable(false);
return 0;
}
int Process::sys$join_thread(int tid, void** exit_value)
{
REQUIRE_PROMISE(thread);
if (exit_value && !validate_write_typed(exit_value))
return -EFAULT;
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread || thread->pid() != pid())
return -ESRCH;
if (thread == Thread::current)
return -EDEADLK;
if (thread->m_joinee == Thread::current)
return -EDEADLK;
ASSERT(thread->m_joiner != Thread::current);
if (thread->m_joiner)
return -EINVAL;
if (!thread->is_joinable())
return -EINVAL;
void* joinee_exit_value = nullptr;
// NOTE: pthread_join() cannot be interrupted by signals. Only by death.
for (;;) {
auto result = Thread::current->block<Thread::JoinBlocker>(*thread, joinee_exit_value);
if (result == Thread::BlockResult::InterruptedByDeath) {
// NOTE: This cleans things up so that Thread::finalize() won't
// get confused about a missing joiner when finalizing the joinee.
InterruptDisabler disabler_t;
if (Thread::current->m_joinee) {
Thread::current->m_joinee->m_joiner = nullptr;
Thread::current->m_joinee = nullptr;
}
break;
}
}
// NOTE: 'thread' is very possibly deleted at this point. Clear it just to be safe.
thread = nullptr;
if (exit_value)
copy_to_user(exit_value, &joinee_exit_value);
return 0;
}
int Process::sys$set_thread_name(int tid, const char* user_name, size_t user_name_length)
{
REQUIRE_PROMISE(thread);
auto name = validate_and_copy_string_from_user(user_name, user_name_length);
if (name.is_null())
return -EFAULT;
const size_t max_thread_name_size = 64;
if (name.length() > max_thread_name_size)
return -EINVAL;
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread || thread->pid() != pid())
return -ESRCH;
thread->set_name(name);
return 0;
}
int Process::sys$get_thread_name(int tid, char* buffer, size_t buffer_size)
{
REQUIRE_PROMISE(thread);
if (buffer_size == 0)
return -EINVAL;
if (!validate_write(buffer, buffer_size))
return -EFAULT;
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread || thread->pid() != pid())
return -ESRCH;
if (thread->name().length() + 1 > (size_t)buffer_size)
return -ENAMETOOLONG;
copy_to_user(buffer, thread->name().characters(), thread->name().length() + 1);
return 0;
}
int Process::sys$gettid()
{
REQUIRE_PROMISE(stdio);
return Thread::current->tid();
}
int Process::sys$donate(int tid)
{
REQUIRE_PROMISE(stdio);
if (tid < 0)
return -EINVAL;
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread || thread->pid() != pid())
return -ESRCH;
Scheduler::donate_to(thread, "sys$donate");
return 0;
}
int Process::sys$rename(const Syscall::SC_rename_params* user_params)
{
REQUIRE_PROMISE(cpath);
Syscall::SC_rename_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
auto old_path = get_syscall_path_argument(params.old_path);
if (old_path.is_error())
return old_path.error();
auto new_path = get_syscall_path_argument(params.new_path);
if (new_path.is_error())
return new_path.error();
return VFS::the().rename(old_path.value(), new_path.value(), current_directory());
}
int Process::sys$ftruncate(int fd, off_t length)
{
REQUIRE_PROMISE(stdio);
if (length < 0)
return -EINVAL;
auto description = file_description(fd);
if (!description)
return -EBADF;
if (!description->is_writable())
return -EBADF;
return description->truncate(static_cast<u64>(length));
}
int Process::sys$watch_file(const char* user_path, size_t path_length)
{
REQUIRE_PROMISE(rpath);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
auto custody_or_error = VFS::the().resolve_path(path.value(), current_directory());
if (custody_or_error.is_error())
return custody_or_error.error();
auto& custody = custody_or_error.value();
auto& inode = custody->inode();
if (!inode.fs().supports_watchers())
return -ENOTSUP;
int fd = alloc_fd();
if (fd < 0)
return fd;
m_fds[fd].set(FileDescription::create(*InodeWatcher::create(inode)));
m_fds[fd].description->set_readable(true);
return fd;
}
int Process::sys$systrace(pid_t pid)
{
REQUIRE_PROMISE(proc);
InterruptDisabler disabler;
auto* peer = Process::from_pid(pid);
if (!peer)
return -ESRCH;
if (peer->uid() != m_euid)
return -EACCES;
int fd = alloc_fd();
if (fd < 0)
return fd;
auto description = FileDescription::create(peer->ensure_tracer());
description->set_readable(true);
m_fds[fd].set(move(description), 0);
return fd;
}
int Process::sys$halt()
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
dbg() << "acquiring FS locks...";
FS::lock_all();
dbg() << "syncing mounted filesystems...";
FS::sync();
dbg() << "attempting system shutdown...";
IO::out16(0x604, 0x2000);
return ESUCCESS;
}
int Process::sys$reboot()
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
dbg() << "acquiring FS locks...";
FS::lock_all();
dbg() << "syncing mounted filesystems...";
FS::sync();
dbg() << "attempting reboot via ACPI";
ACPI::Parser::the().try_acpi_reboot();
dbg() << "attempting reboot via KB Controller...";
IO::out8(0x64, 0xFE);
return ESUCCESS;
}
int Process::sys$mount(const Syscall::SC_mount_params* user_params)
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
Syscall::SC_mount_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
auto source = validate_and_copy_string_from_user(params.source);
auto target = validate_and_copy_string_from_user(params.target);
auto fs_type = validate_and_copy_string_from_user(params.fs_type);
if (source.is_null() || target.is_null() || fs_type.is_null())
return -EFAULT;
dbg() << "mount " << fs_type << ": source " << source << " @ " << target;
auto custody_or_error = VFS::the().resolve_path(target, current_directory());
if (custody_or_error.is_error())
return custody_or_error.error();
auto& target_custody = custody_or_error.value();
RefPtr<FS> fs;
if (params.flags & MS_BIND) {
// We're doing a bind mount.
auto source_or_error = VFS::the().resolve_path(source, current_directory());
if (source_or_error.is_error())
return source_or_error.error();
auto& source_custody = source_or_error.value();
return VFS::the().bind_mount(source_custody, target_custody, params.flags);
}
if (fs_type == "ext2" || fs_type == "Ext2FS") {
auto source_or_error = VFS::the().open(source, O_RDWR, 0, current_directory());
if (source_or_error.is_error())
return source_or_error.error();
auto* device = source_or_error.value()->device();
if (!device || !device->is_block_device()) {
dbg() << "mount: this is not a BlockDevice";
return -ENODEV;
}
auto& block_device = static_cast<BlockDevice&>(*device);
dbg() << "mount: attempting to mount " << block_device.absolute_path() << " on " << target;
fs = Ext2FS::create(block_device);
} else if (fs_type == "proc" || fs_type == "ProcFS") {
fs = ProcFS::create();
} else if (fs_type == "devpts" || fs_type == "DevPtsFS") {
fs = DevPtsFS::create();
} else if (fs_type == "tmp" || fs_type == "TmpFS") {
fs = TmpFS::create();
} else {
return -ENODEV;
}
if (!fs->initialize()) {
dbg() << "mount: failed to initialize " << fs_type << " filesystem on " << source;
return -ENODEV;
}
auto result = VFS::the().mount(fs.release_nonnull(), target_custody, params.flags);
dbg() << "mount: successfully mounted " << source << " on " << target;
return result;
}
int Process::sys$umount(const char* user_mountpoint, size_t mountpoint_length)
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
if (!validate_read(user_mountpoint, mountpoint_length))
return -EFAULT;
auto mountpoint = get_syscall_path_argument(user_mountpoint, mountpoint_length);
if (mountpoint.is_error())
return mountpoint.error();
auto metadata_or_error = VFS::the().lookup_metadata(mountpoint.value(), current_directory());
if (metadata_or_error.is_error())
return metadata_or_error.error();
auto guest_inode_id = metadata_or_error.value().inode;
return VFS::the().unmount(guest_inode_id);
}
ProcessTracer& Process::ensure_tracer()
{
if (!m_tracer)
m_tracer = ProcessTracer::create(m_pid);
return *m_tracer;
}
void Process::FileDescriptionAndFlags::clear()
{
description = nullptr;
flags = 0;
}
void Process::FileDescriptionAndFlags::set(NonnullRefPtr<FileDescription>&& d, u32 f)
{
description = move(d);
flags = f;
}
int Process::sys$mknod(const Syscall::SC_mknod_params* user_params)
{
REQUIRE_PROMISE(dpath);
Syscall::SC_mknod_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!is_superuser() && !is_regular_file(params.mode) && !is_fifo(params.mode) && !is_socket(params.mode))
return -EPERM;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
return VFS::the().mknod(path.value(), params.mode & ~umask(), params.dev, current_directory());
}
int Process::sys$dump_backtrace()
{
dump_backtrace();
return 0;
}
int Process::sys$dbgputch(u8 ch)
{
IO::out8(0xe9, ch);
return 0;
}
int Process::sys$dbgputstr(const u8* characters, int length)
{
if (!length)
return 0;
if (!validate_read(characters, length))
return -EFAULT;
SmapDisabler disabler;
for (int i = 0; i < length; ++i)
IO::out8(0xe9, characters[i]);
return 0;
}
KBuffer Process::backtrace(ProcessInspectionHandle& handle) const
{
KBufferBuilder builder;
for_each_thread([&](Thread& thread) {
builder.appendf("Thread %d (%s):\n", thread.tid(), thread.name().characters());
builder.append(thread.backtrace(handle));
return IterationDecision::Continue;
});
return builder.build();
}
int Process::sys$set_process_icon(int icon_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(icon_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
m_icon_id = icon_id;
return 0;
}
int Process::sys$get_process_name(char* buffer, int buffer_size)
{
REQUIRE_PROMISE(stdio);
if (buffer_size <= 0)
return -EINVAL;
if (!validate_write(buffer, buffer_size))
return -EFAULT;
if (m_name.length() + 1 > (size_t)buffer_size)
return -ENAMETOOLONG;
copy_to_user(buffer, m_name.characters(), m_name.length() + 1);
return 0;
}
// We don't use the flag yet, but we could use it for distinguishing
// random source like Linux, unlike the OpenBSD equivalent. However, if we
// do, we should be able of the caveats that Linux has dealt with.
int Process::sys$getrandom(void* buffer, size_t buffer_size, unsigned int flags __attribute__((unused)))
{
REQUIRE_PROMISE(stdio);
if (buffer_size <= 0)
return -EINVAL;
if (!validate_write(buffer, buffer_size))
return -EFAULT;
SmapDisabler disabler;
get_good_random_bytes((u8*)buffer, buffer_size);
return 0;
}
int Process::sys$setkeymap(const Syscall::SC_setkeymap_params* user_params)
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
Syscall::SC_setkeymap_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
const char* map = params.map;
const char* shift_map = params.shift_map;
const char* alt_map = params.alt_map;
const char* altgr_map = params.altgr_map;
if (!validate_read(map, 0x80))
return -EFAULT;
if (!validate_read(shift_map, 0x80))
return -EFAULT;
if (!validate_read(alt_map, 0x80))
return -EFAULT;
if (!validate_read(altgr_map, 0x80))
return -EFAULT;
SmapDisabler disabler;
KeyboardDevice::the().set_maps(map, shift_map, alt_map, altgr_map);
return 0;
}
int Process::sys$clock_gettime(clockid_t clock_id, timespec* user_ts)
{
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(user_ts))
return -EFAULT;
timespec ts;
memset(&ts, 0, sizeof(ts));
switch (clock_id) {
case CLOCK_MONOTONIC:
ts.tv_sec = TimeManagement::the().seconds_since_boot();
ts.tv_nsec = TimeManagement::the().ticks_this_second() * 1000000;
break;
case CLOCK_REALTIME:
ts.tv_sec = TimeManagement::the().epoch_time();
ts.tv_nsec = TimeManagement::the().ticks_this_second() * 1000000;
break;
default:
return -EINVAL;
}
copy_to_user(user_ts, &ts);
return 0;
}
int Process::sys$clock_settime(clockid_t clock_id, timespec* user_ts)
{
SmapDisabler disabler;
REQUIRE_PROMISE(stdio);
if (!validate_write_typed(user_ts))
return -EFAULT;
switch (clock_id) {
case CLOCK_REALTIME:
TimeManagement::the().set_epoch_time(user_ts->tv_sec);
break;
default:
return -EINVAL;
}
return 0;
}
int Process::sys$clock_nanosleep(const Syscall::SC_clock_nanosleep_params* user_params)
{
REQUIRE_PROMISE(stdio);
Syscall::SC_clock_nanosleep_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (params.requested_sleep && !validate_read_typed(params.requested_sleep))
return -EFAULT;
timespec requested_sleep;
copy_from_user(&requested_sleep, params.requested_sleep);
if (params.remaining_sleep && !validate_write_typed(params.remaining_sleep))
return -EFAULT;
bool is_absolute = params.flags & TIMER_ABSTIME;
switch (params.clock_id) {
case CLOCK_MONOTONIC: {
u64 wakeup_time;
if (is_absolute) {
u64 time_to_wake = (requested_sleep.tv_sec * 1000 + requested_sleep.tv_nsec / 1000000);
wakeup_time = Thread::current->sleep_until(time_to_wake);
} else {
u32 ticks_to_sleep = (requested_sleep.tv_sec * 1000 + requested_sleep.tv_nsec / 1000000);
if (!ticks_to_sleep)
return 0;
wakeup_time = Thread::current->sleep(ticks_to_sleep);
}
if (wakeup_time > g_uptime) {
u32 ticks_left = wakeup_time - g_uptime;
if (!is_absolute && params.remaining_sleep) {
if (!validate_write_typed(params.remaining_sleep)) {
// This can happen because the lock is dropped while
// sleeping, thus giving other threads the opportunity
// to make the region unwritable.
return -EFAULT;
}
timespec remaining_sleep;
memset(&remaining_sleep, 0, sizeof(timespec));
remaining_sleep.tv_sec = ticks_left / TimeManagement::the().ticks_per_second();
ticks_left -= remaining_sleep.tv_sec * TimeManagement::the().ticks_per_second();
remaining_sleep.tv_nsec = ticks_left * 1000000;
copy_to_user(params.remaining_sleep, &remaining_sleep);
}
return -EINTR;
}
return 0;
}
default:
return -EINVAL;
}
}
int Process::sys$sync()
{
REQUIRE_PROMISE(stdio);
VFS::the().sync();
return 0;
}
int Process::sys$yield()
{
REQUIRE_PROMISE(stdio);
Thread::current->yield_without_holding_big_lock();
return 0;
}
int Process::sys$beep()
{
PCSpeaker::tone_on(440);
u64 wakeup_time = Thread::current->sleep(100);
PCSpeaker::tone_off();
if (wakeup_time > g_uptime)
return -EINTR;
return 0;
}
int Process::sys$module_load(const char* user_path, size_t path_length)
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
auto description_or_error = VFS::the().open(path.value(), O_RDONLY, 0, current_directory());
if (description_or_error.is_error())
return description_or_error.error();
auto& description = description_or_error.value();
auto payload = description->read_entire_file();
auto storage = KBuffer::create_with_size(payload.size());
memcpy(storage.data(), payload.data(), payload.size());
payload.clear();
auto elf_image = make<ELFImage>(storage.data(), storage.size());
if (!elf_image->parse())
return -ENOEXEC;
HashMap<String, u8*> section_storage_by_name;
auto module = make<Module>();
elf_image->for_each_section_of_type(SHT_PROGBITS, [&](const ELFImage::Section& section) {
auto section_storage = KBuffer::copy(section.raw_data(), section.size(), Region::Access::Read | Region::Access::Write | Region::Access::Execute);
section_storage_by_name.set(section.name(), section_storage.data());
module->sections.append(move(section_storage));
return IterationDecision::Continue;
});
bool missing_symbols = false;
elf_image->for_each_section_of_type(SHT_PROGBITS, [&](const ELFImage::Section& section) {
auto* section_storage = section_storage_by_name.get(section.name()).value_or(nullptr);
ASSERT(section_storage);
section.relocations().for_each_relocation([&](const ELFImage::Relocation& relocation) {
auto& patch_ptr = *reinterpret_cast<ptrdiff_t*>(section_storage + relocation.offset());
switch (relocation.type()) {
case R_386_PC32: {
// PC-relative relocation
dbg() << "PC-relative relocation: " << relocation.symbol().name();
u32 symbol_address = address_for_kernel_symbol(relocation.symbol().name());
if (symbol_address == 0)
missing_symbols = true;
dbg() << " Symbol address: " << (void*)symbol_address;
ptrdiff_t relative_offset = (char*)symbol_address - ((char*)&patch_ptr + 4);
patch_ptr = relative_offset;
break;
}
case R_386_32: // Absolute relocation
dbg() << "Absolute relocation: '" << relocation.symbol().name() << "' value:" << relocation.symbol().value() << ", index:" << relocation.symbol_index();
if (relocation.symbol().bind() == STB_LOCAL) {
auto* section_storage_containing_symbol = section_storage_by_name.get(relocation.symbol().section().name()).value_or(nullptr);
ASSERT(section_storage_containing_symbol);
u32 symbol_address = (ptrdiff_t)(section_storage_containing_symbol + relocation.symbol().value());
if (symbol_address == 0)
missing_symbols = true;
dbg() << " Symbol address: " << (void*)symbol_address;
patch_ptr += symbol_address;
} else if (relocation.symbol().bind() == STB_GLOBAL) {
u32 symbol_address = address_for_kernel_symbol(relocation.symbol().name());
if (symbol_address == 0)
missing_symbols = true;
dbg() << " Symbol address: " << (void*)symbol_address;
patch_ptr += symbol_address;
} else {
ASSERT_NOT_REACHED();
}
break;
}
return IterationDecision::Continue;
});
return IterationDecision::Continue;
});
if (missing_symbols)
return -EINVAL;
auto* text_base = section_storage_by_name.get(".text").value_or(nullptr);
if (!text_base) {
dbg() << "No .text section found in module!";
return -EINVAL;
}
elf_image->for_each_symbol([&](const ELFImage::Symbol& symbol) {
dbg() << " - " << symbol.type() << " '" << symbol.name() << "' @ " << (void*)symbol.value() << ", size=" << symbol.size();
if (symbol.name() == "module_init") {
module->module_init = (ModuleInitPtr)(text_base + symbol.value());
} else if (symbol.name() == "module_fini") {
module->module_fini = (ModuleFiniPtr)(text_base + symbol.value());
} else if (symbol.name() == "module_name") {
const u8* storage = section_storage_by_name.get(symbol.section().name()).value_or(nullptr);
if (storage)
module->name = String((const char*)(storage + symbol.value()));
}
return IterationDecision::Continue;
});
if (!module->module_init)
return -EINVAL;
if (g_modules->contains(module->name)) {
dbg() << "a module with the name " << module->name << " is already loaded; please unload it first";
return -EEXIST;
}
module->module_init();
auto name = module->name;
g_modules->set(name, move(module));
return 0;
}
int Process::sys$module_unload(const char* user_name, size_t name_length)
{
if (!is_superuser())
return -EPERM;
REQUIRE_NO_PROMISES;
auto module_name = validate_and_copy_string_from_user(user_name, name_length);
if (module_name.is_null())
return -EFAULT;
auto it = g_modules->find(module_name);
if (it == g_modules->end())
return -ENOENT;
if (it->value->module_fini)
it->value->module_fini();
g_modules->remove(it);
return 0;
}
int Process::sys$profiling_enable(pid_t pid)
{
REQUIRE_NO_PROMISES;
InterruptDisabler disabler;
auto* process = Process::from_pid(pid);
if (!process)
return -ESRCH;
if (process->is_dead())
return -ESRCH;
if (!is_superuser() && process->uid() != m_uid)
return -EPERM;
Profiling::start(*process);
process->set_profiling(true);
return 0;
}
int Process::sys$profiling_disable(pid_t pid)
{
InterruptDisabler disabler;
auto* process = Process::from_pid(pid);
if (!process)
return -ESRCH;
if (!is_superuser() && process->uid() != m_uid)
return -EPERM;
process->set_profiling(false);
Profiling::stop();
return 0;
}
void* Process::sys$get_kernel_info_page()
{
REQUIRE_PROMISE(stdio);
return s_info_page_address_for_userspace.as_ptr();
}
Thread& Process::any_thread()
{
Thread* found_thread = nullptr;
for_each_thread([&](auto& thread) {
found_thread = &thread;
return IterationDecision::Break;
});
ASSERT(found_thread);
return *found_thread;
}
WaitQueue& Process::futex_queue(i32* userspace_address)
{
auto& queue = m_futex_queues.ensure((FlatPtr)userspace_address);
if (!queue)
queue = make<WaitQueue>();
return *queue;
}
int Process::sys$futex(const Syscall::SC_futex_params* user_params)
{
REQUIRE_PROMISE(thread);
Syscall::SC_futex_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
i32* userspace_address = params.userspace_address;
int futex_op = params.futex_op;
i32 value = params.val;
const timespec* user_timeout = params.timeout;
if (!validate_read_typed(userspace_address))
return -EFAULT;
if (user_timeout && !validate_read_typed(user_timeout))
return -EFAULT;
timespec timeout { 0, 0 };
if (user_timeout)
copy_from_user(&timeout, user_timeout);
i32 user_value;
switch (futex_op) {
case FUTEX_WAIT:
copy_from_user(&user_value, userspace_address);
if (user_value != value)
return -EAGAIN;
// FIXME: This is supposed to be interruptible by a signal, but right now WaitQueue cannot be interrupted.
// FIXME: Support timeout!
Thread::current->wait_on(futex_queue(userspace_address));
break;
case FUTEX_WAKE:
if (value == 0)
return 0;
if (value == 1) {
futex_queue(userspace_address).wake_one();
} else {
// FIXME: Wake exactly (value) waiters.
futex_queue(userspace_address).wake_all();
}
break;
}
return 0;
}
int Process::sys$set_thread_boost(int tid, int amount)
{
REQUIRE_PROMISE(proc);
if (amount < 0 || amount > 20)
return -EINVAL;
InterruptDisabler disabler;
auto* thread = Thread::from_tid(tid);
if (!thread)
return -ESRCH;
if (thread->state() == Thread::State::Dead || thread->state() == Thread::State::Dying)
return -ESRCH;
if (!is_superuser() && thread->process().uid() != euid())
return -EPERM;
thread->set_priority_boost(amount);
return 0;
}
int Process::sys$set_process_boost(pid_t pid, int amount)
{
REQUIRE_PROMISE(proc);
if (amount < 0 || amount > 20)
return -EINVAL;
InterruptDisabler disabler;
auto* process = Process::from_pid(pid);
if (!process || process->is_dead())
return -ESRCH;
if (!is_superuser() && process->uid() != euid())
return -EPERM;
process->m_priority_boost = amount;
return 0;
}
int Process::sys$chroot(const char* user_path, size_t path_length, int mount_flags)
{
if (!is_superuser())
return -EPERM;
REQUIRE_PROMISE(chroot);
auto path = get_syscall_path_argument(user_path, path_length);
if (path.is_error())
return path.error();
auto directory_or_error = VFS::the().open_directory(path.value(), current_directory());
if (directory_or_error.is_error())
return directory_or_error.error();
auto directory = directory_or_error.value();
m_root_directory_relative_to_global_root = directory;
int chroot_mount_flags = mount_flags == -1 ? directory->mount_flags() : mount_flags;
set_root_directory(Custody::create(nullptr, "", directory->inode(), chroot_mount_flags));
return 0;
}
Custody& Process::root_directory()
{
if (!m_root_directory)
m_root_directory = VFS::the().root_custody();
return *m_root_directory;
}
Custody& Process::root_directory_relative_to_global_root()
{
if (!m_root_directory_relative_to_global_root)
m_root_directory_relative_to_global_root = root_directory();
return *m_root_directory_relative_to_global_root;
}
void Process::set_root_directory(const Custody& root)
{
m_root_directory = root;
}
int Process::sys$pledge(const Syscall::SC_pledge_params* user_params)
{
Syscall::SC_pledge_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (params.promises.length > 1024 || params.execpromises.length > 1024)
return -E2BIG;
String promises;
if (params.promises.characters) {
promises = validate_and_copy_string_from_user(params.promises);
if (promises.is_null())
return -EFAULT;
}
String execpromises;
if (params.execpromises.characters) {
execpromises = validate_and_copy_string_from_user(params.execpromises);
if (execpromises.is_null())
return -EFAULT;
}
auto parse_pledge = [&](auto& pledge_spec, u32& mask) {
auto parts = pledge_spec.split_view(' ');
for (auto& part : parts) {
#define __ENUMERATE_PLEDGE_PROMISE(x) \
if (part == #x) { \
mask |= (1u << (u32)Pledge::x); \
continue; \
}
ENUMERATE_PLEDGE_PROMISES
#undef __ENUMERATE_PLEDGE_PROMISE
if (part == "dns") {
// "dns" is an alias for "unix" since DNS queries go via LookupServer
mask |= (1u << (u32)Pledge::unix);
continue;
}
return false;
}
return true;
};
if (!promises.is_null()) {
u32 new_promises = 0;
if (!parse_pledge(promises, new_promises))
return -EINVAL;
if (m_promises && (!new_promises || new_promises & ~m_promises))
return -EPERM;
m_promises = new_promises;
}
if (!execpromises.is_null()) {
u32 new_execpromises = 0;
if (!parse_pledge(execpromises, new_execpromises))
return -EINVAL;
if (m_execpromises && (!new_execpromises || new_execpromises & ~m_execpromises))
return -EPERM;
m_execpromises = new_execpromises;
}
return 0;
}
Region& Process::add_region(NonnullOwnPtr<Region> region)
{
auto* ptr = region.ptr();
m_regions.append(move(region));
return *ptr;
}
int Process::sys$unveil(const Syscall::SC_unveil_params* user_params)
{
Syscall::SC_unveil_params params;
if (!validate_read_and_copy_typed(¶ms, user_params))
return -EFAULT;
if (!params.path.characters && !params.permissions.characters) {
m_veil_state = VeilState::Locked;
return 0;
}
if (m_veil_state == VeilState::Locked)
return -EPERM;
if (!params.path.characters || !params.permissions.characters)
return -EINVAL;
if (params.permissions.length > 4)
return -EINVAL;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
if (path.value().is_empty() || path.value().characters()[0] != '/')
return -EINVAL;
auto custody_or_error = VFS::the().resolve_path_without_veil(path.value(), root_directory());
if (custody_or_error.is_error())
// FIXME Should this be EINVAL?
return custody_or_error.error();
auto& custody = custody_or_error.value();
auto new_unveiled_path = custody->absolute_path();
auto permissions = validate_and_copy_string_from_user(params.permissions);
if (permissions.is_null())
return -EFAULT;
unsigned new_permissions = 0;
for (size_t i = 0; i < permissions.length(); ++i) {
switch (permissions[i]) {
case 'r':
new_permissions |= UnveiledPath::Access::Read;
break;
case 'w':
new_permissions |= UnveiledPath::Access::Write;
break;
case 'x':
new_permissions |= UnveiledPath::Access::Execute;
break;
case 'c':
new_permissions |= UnveiledPath::Access::CreateOrRemove;
break;
default:
return -EINVAL;
}
}
for (size_t i = 0; i < m_unveiled_paths.size(); ++i) {
auto& unveiled_path = m_unveiled_paths[i];
if (unveiled_path.path == new_unveiled_path) {
if (new_permissions & ~unveiled_path.permissions)
return -EPERM;
unveiled_path.permissions = new_permissions;
return 0;
}
}
m_unveiled_paths.append({ new_unveiled_path, new_permissions });
ASSERT(m_veil_state != VeilState::Locked);
m_veil_state = VeilState::Dropped;
return 0;
}
int Process::sys$perf_event(int type, FlatPtr arg1, FlatPtr arg2)
{
if (!m_perf_event_buffer)
m_perf_event_buffer = make<PerformanceEventBuffer>();
return m_perf_event_buffer->append(type, arg1, arg2);
}
void Process::set_tty(TTY* tty)
{
m_tty = tty;
}
OwnPtr<Process::ELFBundle> Process::elf_bundle() const
{
if (!m_executable)
return nullptr;
auto bundle = make<ELFBundle>();
ASSERT(m_executable->inode().shared_vmobject());
auto& vmobject = *m_executable->inode().shared_vmobject();
bundle->region = MM.allocate_kernel_region_with_vmobject(const_cast<SharedInodeVMObject&>(vmobject), vmobject.size(), "ELF bundle", Region::Access::Read);
if (!bundle->region)
return nullptr;
bundle->elf_loader = make<ELFLoader>(bundle->region->vaddr().as_ptr(), bundle->region->size());
return bundle;
}
int Process::sys$get_stack_bounds(FlatPtr* user_stack_base, size_t* user_stack_size)
{
if (!validate_write_typed(user_stack_base))
return -EFAULT;
if (!validate_write_typed(user_stack_size))
return -EFAULT;
FlatPtr stack_pointer = Thread::current->get_register_dump_from_stack().userspace_esp;
auto* stack_region = MM.region_from_vaddr(*this, VirtualAddress(stack_pointer));
if (!stack_region) {
ASSERT_NOT_REACHED();
return -EINVAL;
}
FlatPtr stack_base = stack_region->range().base().get();
size_t stack_size = stack_region->size();
copy_to_user(user_stack_base, &stack_base);
copy_to_user(user_stack_size, &stack_size);
return 0;
}
}