| // Copyright 2017 The Crashpad Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "snapshot/linux/debug_rendezvous.h" |
| |
| #include <stdint.h> |
| |
| #include <set> |
| |
| #include "base/logging.h" |
| #include "build/build_config.h" |
| |
| #if BUILDFLAG(IS_ANDROID) |
| #include <android/api-level.h> |
| #endif |
| |
| namespace crashpad { |
| |
| namespace { |
| |
| struct Traits32 { |
| using Integer = int32_t; |
| using Address = uint32_t; |
| }; |
| |
| struct Traits64 { |
| using Integer = int64_t; |
| using Address = uint64_t; |
| }; |
| |
| template <typename Traits> |
| struct DebugRendezvousSpecific { |
| typename Traits::Integer r_version; |
| typename Traits::Address r_map; |
| typename Traits::Address r_brk; |
| typename Traits::Integer r_state; |
| typename Traits::Address r_ldbase; |
| }; |
| |
| template <typename Traits> |
| struct LinkEntrySpecific { |
| typename Traits::Address l_addr; |
| typename Traits::Address l_name; |
| typename Traits::Address l_ld; |
| typename Traits::Address l_next; |
| typename Traits::Address l_prev; |
| }; |
| |
| template <typename Traits> |
| bool ReadLinkEntry(const ProcessMemoryRange& memory, |
| LinuxVMAddress* address, |
| DebugRendezvous::LinkEntry* entry_out) { |
| LinkEntrySpecific<Traits> entry; |
| if (!memory.Read(*address, sizeof(entry), &entry)) { |
| return false; |
| } |
| |
| std::string name; |
| if (!memory.ReadCStringSizeLimited(entry.l_name, 4096, &name)) { |
| name.clear(); |
| } |
| |
| entry_out->load_bias = entry.l_addr; |
| entry_out->dynamic_array = entry.l_ld; |
| entry_out->name.swap(name); |
| |
| *address = entry.l_next; |
| return true; |
| } |
| |
| } // namespace |
| |
| DebugRendezvous::LinkEntry::LinkEntry() |
| : name(), load_bias(0), dynamic_array(0) {} |
| |
| DebugRendezvous::DebugRendezvous() |
| : modules_(), executable_(), initialized_() {} |
| |
| DebugRendezvous::~DebugRendezvous() {} |
| |
| bool DebugRendezvous::Initialize(const ProcessMemoryRange& memory, |
| LinuxVMAddress address) { |
| INITIALIZATION_STATE_SET_INITIALIZING(initialized_); |
| if (!(memory.Is64Bit() ? InitializeSpecific<Traits64>(memory, address) |
| : InitializeSpecific<Traits32>(memory, address))) { |
| return false; |
| } |
| INITIALIZATION_STATE_SET_VALID(initialized_); |
| return true; |
| } |
| |
| const DebugRendezvous::LinkEntry* DebugRendezvous::Executable() const { |
| INITIALIZATION_STATE_DCHECK_VALID(initialized_); |
| return &executable_; |
| } |
| |
| const std::vector<DebugRendezvous::LinkEntry>& DebugRendezvous::Modules() |
| const { |
| INITIALIZATION_STATE_DCHECK_VALID(initialized_); |
| return modules_; |
| } |
| |
| template <typename Traits> |
| bool DebugRendezvous::InitializeSpecific(const ProcessMemoryRange& memory, |
| LinuxVMAddress address) { |
| DebugRendezvousSpecific<Traits> debug; |
| if (!memory.Read(address, sizeof(debug), &debug)) { |
| return false; |
| } |
| if (debug.r_version != 1) { |
| LOG(ERROR) << "unexpected version " << debug.r_version; |
| return false; |
| } |
| |
| LinuxVMAddress link_entry_address = debug.r_map; |
| if (!ReadLinkEntry<Traits>(memory, &link_entry_address, &executable_)) { |
| return false; |
| } |
| |
| std::set<LinuxVMAddress> visited; |
| while (link_entry_address) { |
| if (!visited.insert(link_entry_address).second) { |
| LOG(ERROR) << "cycle at address 0x" << std::hex << link_entry_address; |
| return false; |
| } |
| |
| LinkEntry entry; |
| if (!ReadLinkEntry<Traits>(memory, &link_entry_address, &entry)) { |
| return false; |
| } |
| modules_.push_back(entry); |
| } |
| |
| #if BUILDFLAG(IS_ANDROID) |
| // Android P (API 28) mistakenly places the vdso in the first entry in the |
| // link map. |
| const int android_runtime_api = android_get_device_api_level(); |
| if (android_runtime_api == 28 && executable_.name == "[vdso]") { |
| LinkEntry executable = modules_[0]; |
| modules_[0] = executable_; |
| executable_ = executable; |
| } |
| #endif // BUILDFLAG(IS_ANDROID) |
| |
| return true; |
| } |
| |
| } // namespace crashpad |