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-rw-r--r--lib/asan/asan_debugging.cpp146
1 files changed, 146 insertions, 0 deletions
diff --git a/lib/asan/asan_debugging.cpp b/lib/asan/asan_debugging.cpp
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+++ b/lib/asan/asan_debugging.cpp
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+//===-- 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, &region_address, &region_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;
+}