//===-- MachVMRegion.cpp ----------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Created by Greg Clayton on 6/26/07.
//
//===----------------------------------------------------------------------===//
#include "MachVMRegion.h"
#include "DNBLog.h"
#include <cassert>
#include <mach/mach_vm.h>
MachVMRegion::MachVMRegion(task_t task)
: m_task(task), m_addr(INVALID_NUB_ADDRESS), m_err(),
m_start(INVALID_NUB_ADDRESS), m_size(0), m_depth(-1),
m_curr_protection(0), m_protection_addr(INVALID_NUB_ADDRESS),
m_protection_size(0) {
memset(&m_data, 0, sizeof(m_data));
}
MachVMRegion::~MachVMRegion() {
// Restore any original protections and clear our vars
Clear();
}
void MachVMRegion::Clear() {
RestoreProtections();
m_addr = INVALID_NUB_ADDRESS;
m_err.Clear();
m_start = INVALID_NUB_ADDRESS;
m_size = 0;
m_depth = -1;
memset(&m_data, 0, sizeof(m_data));
m_curr_protection = 0;
m_protection_addr = INVALID_NUB_ADDRESS;
m_protection_size = 0;
}
bool MachVMRegion::SetProtections(mach_vm_address_t addr, mach_vm_size_t size,
vm_prot_t prot) {
if (ContainsAddress(addr)) {
mach_vm_size_t prot_size = size;
mach_vm_address_t end_addr = EndAddress();
if (prot_size > (end_addr - addr))
prot_size = end_addr - addr;
if (prot_size > 0) {
if (prot == (m_curr_protection & VM_PROT_ALL)) {
DNBLogThreadedIf(LOG_MEMORY_PROTECTIONS | LOG_VERBOSE,
"MachVMRegion::%s: protections (%u) already "
"sufficient for task 0x%4.4x at address 0x%8.8llx) ",
__FUNCTION__, prot, m_task, (uint64_t)addr);
// Protections are already set as requested...
return true;
} else {
m_err = ::mach_vm_protect(m_task, addr, prot_size, 0, prot);
if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS))
m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = "
"0x%8.8llx, size = %llu, set_max = %i, prot = %u )",
m_task, (uint64_t)addr, (uint64_t)prot_size, 0,
prot);
if (m_err.Fail()) {
// Try again with the ability to create a copy on write region
m_err = ::mach_vm_protect(m_task, addr, prot_size, 0,
prot | VM_PROT_COPY);
if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS) || m_err.Fail())
m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = "
"0x%8.8llx, size = %llu, set_max = %i, prot = %u "
")",
m_task, (uint64_t)addr, (uint64_t)prot_size, 0,
prot | VM_PROT_COPY);
}
if (m_err.Success()) {
m_curr_protection = prot;
m_protection_addr = addr;
m_protection_size = prot_size;
return true;
}
}
} else {
DNBLogThreadedIf(LOG_MEMORY_PROTECTIONS | LOG_VERBOSE,
"%s: Zero size for task 0x%4.4x at address 0x%8.8llx) ",
__FUNCTION__, m_task, (uint64_t)addr);
}
}
return false;
}
bool MachVMRegion::RestoreProtections() {
if (m_curr_protection != m_data.protection && m_protection_size > 0) {
m_err = ::mach_vm_protect(m_task, m_protection_addr, m_protection_size, 0,
m_data.protection);
if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS) || m_err.Fail())
m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = 0x%8.8llx, "
"size = %llu, set_max = %i, prot = %u )",
m_task, (uint64_t)m_protection_addr,
(uint64_t)m_protection_size, 0, m_data.protection);
if (m_err.Success()) {
m_protection_size = 0;
m_protection_addr = INVALID_NUB_ADDRESS;
m_curr_protection = m_data.protection;
return true;
}
} else {
m_err.Clear();
return true;
}
return false;
}
bool MachVMRegion::GetRegionForAddress(nub_addr_t addr) {
// Restore any original protections and clear our vars
Clear();
m_err.Clear();
m_addr = addr;
m_start = addr;
m_depth = 1024;
mach_msg_type_number_t info_size = kRegionInfoSize;
static_assert(sizeof(info_size) == 4);
m_err =
::mach_vm_region_recurse(m_task, &m_start, &m_size, &m_depth,
(vm_region_recurse_info_t)&m_data, &info_size);
const bool failed = m_err.Fail();
const bool log_protections = DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS);
if (log_protections || failed)
m_err.LogThreaded("::mach_vm_region_recurse ( task = 0x%4.4x, address => "
"0x%8.8llx, size => %llu, nesting_depth => %d, info => "
"%p, infoCnt => %d) addr = 0x%8.8llx ",
m_task, (uint64_t)m_start, (uint64_t)m_size, m_depth,
&m_data, info_size, (uint64_t)addr);
if (failed)
return false;
if (log_protections) {
DNBLogThreaded("info = { prot = %u, "
"max_prot = %u, "
"inheritance = 0x%8.8x, "
"offset = 0x%8.8llx, "
"user_tag = 0x%8.8x, "
"ref_count = %u, "
"shadow_depth = %u, "
"ext_pager = %u, "
"share_mode = %u, "
"is_submap = %d, "
"behavior = %d, "
"object_id = 0x%8.8x, "
"user_wired_count = 0x%4.4x }",
m_data.protection, m_data.max_protection, m_data.inheritance,
(uint64_t)m_data.offset, m_data.user_tag, m_data.ref_count,
m_data.shadow_depth, m_data.external_pager,
m_data.share_mode, m_data.is_submap, m_data.behavior,
m_data.object_id, m_data.user_wired_count);
}
m_curr_protection = m_data.protection;
// We make a request for an address and got no error back, but this
// doesn't mean that "addr" is in the range. The data in this object will
// be valid though, so you could see where the next region begins. So we
// return false, yet leave "m_err" with a successfull return code.
return !((addr < m_start) || (addr >= (m_start + m_size)));
}
uint32_t MachVMRegion::GetDNBPermissions() const {
if (m_addr == INVALID_NUB_ADDRESS || m_start == INVALID_NUB_ADDRESS ||
m_size == 0)
return 0;
uint32_t dnb_permissions = 0;
if ((m_data.protection & VM_PROT_READ) == VM_PROT_READ)
dnb_permissions |= eMemoryPermissionsReadable;
if ((m_data.protection & VM_PROT_WRITE) == VM_PROT_WRITE)
dnb_permissions |= eMemoryPermissionsWritable;
if ((m_data.protection & VM_PROT_EXECUTE) == VM_PROT_EXECUTE)
dnb_permissions |= eMemoryPermissionsExecutable;
return dnb_permissions;
}
std::vector<std::string> MachVMRegion::GetMemoryTypes() const {
std::vector<std::string> types;
if (m_data.user_tag == VM_MEMORY_STACK) {
if (m_data.protection == VM_PROT_NONE) {
types.push_back("stack-guard");
} else {
types.push_back("stack");
}
}
if (m_data.user_tag == VM_MEMORY_MALLOC) {
if (m_data.protection == VM_PROT_NONE)
types.push_back("malloc-guard");
else if (m_data.share_mode == SM_EMPTY)
types.push_back("malloc-reserved");
else
types.push_back("malloc-metadata");
}
if (m_data.user_tag == VM_MEMORY_MALLOC_NANO ||
m_data.user_tag == VM_MEMORY_MALLOC_TINY ||
m_data.user_tag == VM_MEMORY_MALLOC_SMALL ||
m_data.user_tag == VM_MEMORY_MALLOC_LARGE ||
m_data.user_tag == VM_MEMORY_MALLOC_LARGE_REUSED ||
m_data.user_tag == VM_MEMORY_MALLOC_LARGE_REUSABLE ||
m_data.user_tag == VM_MEMORY_MALLOC_HUGE ||
m_data.user_tag == VM_MEMORY_REALLOC ||
m_data.user_tag == VM_MEMORY_SBRK) {
types.push_back("heap");
if (m_data.user_tag == VM_MEMORY_MALLOC_TINY) {
types.push_back("malloc-tiny");
}
if (m_data.user_tag == VM_MEMORY_MALLOC_LARGE) {
types.push_back("malloc-large");
}
if (m_data.user_tag == VM_MEMORY_MALLOC_SMALL) {
types.push_back("malloc-small");
}
}
return types;
}