| //===-- asan_debugging.cpp ------------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is a part of AddressSanitizer, an address sanity checker. |
| // |
| // This file contains various functions that are generally useful to call when |
| // using a debugger (LLDB, GDB). |
| //===----------------------------------------------------------------------===// |
| |
| #include "asan_allocator.h" |
| #include "asan_descriptions.h" |
| #include "asan_flags.h" |
| #include "asan_internal.h" |
| #include "asan_mapping.h" |
| #include "asan_report.h" |
| #include "asan_thread.h" |
| |
| namespace { |
| using namespace __asan; |
| |
| static void FindInfoForStackVar(uptr addr, const char *frame_descr, uptr offset, |
| char *name, uptr name_size, |
| uptr *region_address, uptr *region_size) { |
| InternalMmapVector<StackVarDescr> vars; |
| vars.reserve(16); |
| if (!ParseFrameDescription(frame_descr, &vars)) { |
| return; |
| } |
| |
| for (uptr i = 0; i < vars.size(); i++) { |
| if (offset <= vars[i].beg + vars[i].size) { |
| // We use name_len + 1 because strlcpy will guarantee a \0 at the end, so |
| // if we're limiting the copy due to name_len, we add 1 to ensure we copy |
| // the whole name and then terminate with '\0'. |
| internal_strlcpy(name, vars[i].name_pos, |
| Min(name_size, vars[i].name_len + 1)); |
| *region_address = addr - (offset - vars[i].beg); |
| *region_size = vars[i].size; |
| return; |
| } |
| } |
| } |
| |
| uptr AsanGetStack(uptr addr, uptr *trace, u32 size, u32 *thread_id, |
| bool alloc_stack) { |
| AsanChunkView chunk = FindHeapChunkByAddress(addr); |
| if (!chunk.IsValid()) return 0; |
| |
| StackTrace stack(nullptr, 0); |
| if (alloc_stack) { |
| if (chunk.AllocTid() == kInvalidTid) return 0; |
| stack = chunk.GetAllocStack(); |
| if (thread_id) *thread_id = chunk.AllocTid(); |
| } else { |
| if (chunk.FreeTid() == kInvalidTid) return 0; |
| stack = chunk.GetFreeStack(); |
| if (thread_id) *thread_id = chunk.FreeTid(); |
| } |
| |
| if (trace && size) { |
| size = Min(size, Min(stack.size, kStackTraceMax)); |
| for (uptr i = 0; i < size; i++) |
| trace[i] = StackTrace::GetPreviousInstructionPc(stack.trace[i]); |
| |
| return size; |
| } |
| |
| return 0; |
| } |
| |
| } // namespace |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| const char *__asan_locate_address(uptr addr, char *name, uptr name_size, |
| uptr *region_address_ptr, |
| uptr *region_size_ptr) { |
| AddressDescription descr(addr); |
| uptr region_address = 0; |
| uptr region_size = 0; |
| const char *region_kind = nullptr; |
| if (name && name_size > 0) name[0] = 0; |
| |
| if (auto shadow = descr.AsShadow()) { |
| // region_{address,size} are already 0 |
| switch (shadow->kind) { |
| case kShadowKindLow: |
| region_kind = "low shadow"; |
| break; |
| case kShadowKindGap: |
| region_kind = "shadow gap"; |
| break; |
| case kShadowKindHigh: |
| region_kind = "high shadow"; |
| break; |
| } |
| } else if (auto heap = descr.AsHeap()) { |
| region_kind = "heap"; |
| region_address = heap->chunk_access.chunk_begin; |
| region_size = heap->chunk_access.chunk_size; |
| } else if (auto stack = descr.AsStack()) { |
| region_kind = "stack"; |
| if (!stack->frame_descr) { |
| // region_{address,size} are already 0 |
| } else { |
| FindInfoForStackVar(addr, stack->frame_descr, stack->offset, name, |
| name_size, ®ion_address, ®ion_size); |
| } |
| } else if (auto global = descr.AsGlobal()) { |
| region_kind = "global"; |
| auto &g = global->globals[0]; |
| internal_strlcpy(name, g.name, name_size); |
| region_address = g.beg; |
| region_size = g.size; |
| } else { |
| // region_{address,size} are already 0 |
| region_kind = "heap-invalid"; |
| } |
| |
| CHECK(region_kind); |
| if (region_address_ptr) *region_address_ptr = region_address; |
| if (region_size_ptr) *region_size_ptr = region_size; |
| return region_kind; |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| uptr __asan_get_alloc_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) { |
| return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ true); |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| uptr __asan_get_free_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) { |
| return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ false); |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __asan_get_shadow_mapping(uptr *shadow_scale, uptr *shadow_offset) { |
| if (shadow_scale) |
| *shadow_scale = SHADOW_SCALE; |
| if (shadow_offset) |
| *shadow_offset = SHADOW_OFFSET; |
| } |