AddressSanitizer run-time library. Not yet integrated with the compiler-rt build system, but can be built using the old makefile. See details in README.txt
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@145463 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/asan/asan_stack.cc b/lib/asan/asan_stack.cc
new file mode 100644
index 0000000..08a70aa
--- /dev/null
+++ b/lib/asan/asan_stack.cc
@@ -0,0 +1,280 @@
+//===-- asan_stack.cc -------------------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Code for ASan stack trace.
+//===----------------------------------------------------------------------===//
+#include "asan_interceptors.h"
+#include "asan_lock.h"
+#include "asan_stack.h"
+#include "asan_thread.h"
+#include "asan_thread_registry.h"
+
+#include <string.h>
+
+#ifdef ASAN_USE_SYSINFO
+#include "sysinfo/sysinfo.h"
+#endif
+
+#ifdef ASAN_USE_EXTERNAL_SYMBOLIZER
+extern bool
+ASAN_USE_EXTERNAL_SYMBOLIZER(const void *pc, char *out, int out_size);
+#endif
+
+namespace __asan {
+
+// ----------------------- ProcSelfMaps ----------------------------- {{{1
+#ifdef ASAN_USE_SYSINFO
+class ProcSelfMaps {
+ public:
+ void Init() {
+ ScopedLock lock(&mu_);
+ if (map_size_ != 0) return; // already inited
+ if (FLAG_v >= 2) {
+ Printf("ProcSelfMaps::Init()\n");
+ }
+ ProcMapsIterator it(0, &proc_self_maps_); // 0 means "current pid"
+
+ uint64 start, end, offset;
+ int64 inode;
+ char *flags, *filename;
+ CHECK(map_size_ == 0);
+ while (it.Next(&start, &end, &flags, &offset, &inode, &filename)) {
+ CHECK(map_size_ < kMaxProcSelfMapsSize);
+ Mapping &mapping = memory_map[map_size_];
+ mapping.beg = start;
+ mapping.end = end;
+ mapping.offset = offset;
+ real_strncpy(mapping.name,
+ filename, ASAN_ARRAY_SIZE(mapping.name));
+ mapping.name[ASAN_ARRAY_SIZE(mapping.name) - 1] = 0;
+ if (FLAG_v >= 2) {
+ Printf("[%ld] [%p,%p] off %p %s\n", map_size_,
+ mapping.beg, mapping.end, mapping.offset, mapping.name);
+ }
+ map_size_++;
+ }
+ }
+
+ void Print() {
+ Printf("%s\n", proc_self_maps_);
+ }
+
+ void PrintPc(uintptr_t pc, int idx) {
+ for (size_t i = 0; i < map_size_; i++) {
+ Mapping &m = memory_map[i];
+ if (pc >= m.beg && pc < m.end) {
+ uintptr_t offset = pc - m.beg;
+ if (i == 0) offset = pc;
+ Printf(" #%d 0x%lx (%s+0x%lx)\n", idx, pc, m.name, offset);
+ return;
+ }
+ }
+ Printf(" #%d 0x%lx\n", idx, pc);
+ }
+
+ private:
+ void copy_until_new_line(const char *str, char *dest, size_t max_size) {
+ size_t i = 0;
+ for (; str[i] && str[i] != '\n' && i < max_size - 1; i++) {
+ dest[i] = str[i];
+ }
+ dest[i] = 0;
+ }
+
+
+ struct Mapping {
+ uintptr_t beg, end, offset;
+ char name[1000];
+ };
+ static const size_t kMaxNumMapEntries = 4096;
+ static const size_t kMaxProcSelfMapsSize = 1 << 20;
+ ProcMapsIterator::Buffer proc_self_maps_;
+ size_t map_size_;
+ Mapping memory_map[kMaxNumMapEntries];
+
+ static AsanLock mu_;
+};
+
+static ProcSelfMaps proc_self_maps;
+AsanLock ProcSelfMaps::mu_(LINKER_INITIALIZED);
+
+
+void AsanStackTrace::PrintStack(uintptr_t *addr, size_t size) {
+ proc_self_maps.Init();
+ for (size_t i = 0; i < size && addr[i]; i++) {
+ uintptr_t pc = addr[i];
+ // int line;
+ proc_self_maps.PrintPc(pc, i);
+ // Printf(" #%ld 0x%lx %s\n", i, pc, rtn.c_str());
+ }
+}
+#elif defined(ASAN_USE_EXTERNAL_SYMBOLIZER)
+void AsanStackTrace::PrintStack(uintptr_t *addr, size_t size) {
+ for (size_t i = 0; i < size && addr[i]; i++) {
+ uintptr_t pc = addr[i];
+ char buff[4096];
+ ASAN_USE_EXTERNAL_SYMBOLIZER((void*)pc, buff, sizeof(buff));
+ Printf(" #%ld 0x%lx %s\n", i, pc, buff);
+ }
+}
+
+#else // ASAN_USE_SYSINFO
+void AsanStackTrace::PrintStack(uintptr_t *addr, size_t size) {
+ for (size_t i = 0; i < size && addr[i]; i++) {
+ uintptr_t pc = addr[i];
+ Printf(" #%ld 0x%lx\n", i, pc);
+ }
+}
+#endif // ASAN_USE_SYSINFO
+
+#ifdef __arm__
+#define UNWIND_STOP _URC_END_OF_STACK
+#define UNWIND_CONTINUE _URC_OK
+#else
+#define UNWIND_STOP _URC_NORMAL_STOP
+#define UNWIND_CONTINUE _URC_NO_REASON
+#endif
+
+// ----------------------- AsanStackTrace ----------------------------- {{{1
+uintptr_t AsanStackTrace::GetCurrentPc() {
+ return GET_CALLER_PC();
+}
+
+void AsanStackTrace::FastUnwindStack(uintptr_t pc, uintptr_t bp) {
+ CHECK(size == 0 && trace[0] == pc);
+ size = 1;
+ if (!asan_inited) return;
+ AsanThread *t = asanThreadRegistry().GetCurrent();
+ if (!t) return;
+ uintptr_t *frame = (uintptr_t*)bp;
+ uintptr_t *prev_frame = frame;
+ uintptr_t *top = (uintptr_t*)t->stack_top();
+ uintptr_t *bottom = (uintptr_t*)t->stack_bottom();
+ while (frame >= prev_frame &&
+ frame < top &&
+ frame > bottom &&
+ size < max_size) {
+ uintptr_t pc1 = frame[1];
+ if (pc1 != pc) {
+ trace[size++] = pc1;
+ }
+ prev_frame = frame;
+ frame = (uintptr_t*)frame[0];
+ }
+}
+
+// On 32-bits we don't compress stack traces.
+// On 64-bits we compress stack traces: if a given pc differes slightly from
+// the previous one, we record a 31-bit offset instead of the full pc.
+size_t AsanStackTrace::CompressStack(AsanStackTrace *stack,
+ uint32_t *compressed, size_t size) {
+#if __WORDSIZE == 32
+ // Don't compress, just copy.
+ size_t res = 0;
+ for (size_t i = 0; i < stack->size && i < size; i++) {
+ compressed[i] = stack->trace[i];
+ res++;
+ }
+ for (size_t i = stack->size; i < size; i++) {
+ compressed[i] = 0;
+ }
+#else // 64 bits, compress.
+ uintptr_t prev_pc = 0;
+ const uintptr_t kMaxOffset = (1ULL << 30) - 1;
+ uintptr_t c_index = 0;
+ size_t res = 0;
+ for (size_t i = 0, n = stack->size; i < n; i++) {
+ uintptr_t pc = stack->trace[i];
+ if (!pc) break;
+ if ((int64_t)pc < 0) break;
+ // Printf("C pc[%ld] %lx\n", i, pc);
+ if (prev_pc - pc < kMaxOffset || pc - prev_pc < kMaxOffset) {
+ uintptr_t offset = (int64_t)(pc - prev_pc);
+ offset |= (1U << 31);
+ if (c_index >= size) break;
+ // Printf("C co[%ld] offset %lx\n", i, offset);
+ compressed[c_index++] = offset;
+ } else {
+ uintptr_t hi = pc >> 32;
+ uintptr_t lo = (pc << 32) >> 32;
+ CHECK((hi & (1 << 31)) == 0);
+ if (c_index + 1 >= size) break;
+ // Printf("C co[%ld] hi/lo: %lx %lx\n", c_index, hi, lo);
+ compressed[c_index++] = hi;
+ compressed[c_index++] = lo;
+ }
+ res++;
+ prev_pc = pc;
+ }
+ for (size_t i = c_index; i < size; i++) {
+ compressed[i] = 0;
+ }
+#endif // __WORDSIZE
+
+ // debug-only code
+#if 0
+ AsanStackTrace check_stack;
+ UncompressStack(&check_stack, compressed, size);
+ if (res < check_stack.size) {
+ Printf("res %ld check_stack.size %ld; c_size %ld\n", res,
+ check_stack.size, size);
+ }
+ // |res| may be greater than check_stack.size, because
+ // UncompressStack(CompressStack(stack)) eliminates the 0x0 frames.
+ CHECK(res >= check_stack.size);
+ CHECK(0 == memcmp(check_stack.trace, stack->trace,
+ check_stack.size * sizeof(uintptr_t)));
+#endif
+
+ return res;
+}
+
+void AsanStackTrace::UncompressStack(AsanStackTrace *stack,
+ uint32_t *compressed, size_t size) {
+#if __WORDSIZE == 32
+ // Don't uncompress, just copy.
+ stack->size = 0;
+ for (size_t i = 0; i < size && i < kStackTraceMax; i++) {
+ if (!compressed[i]) break;
+ stack->size++;
+ stack->trace[i] = compressed[i];
+ }
+#else // 64 bits, uncompress
+ uintptr_t prev_pc = 0;
+ stack->size = 0;
+ for (size_t i = 0; i < size && stack->size < kStackTraceMax; i++) {
+ uint32_t x = compressed[i];
+ uintptr_t pc = 0;
+ if (x & (1U << 31)) {
+ // Printf("U co[%ld] offset: %x\n", i, x);
+ // this is an offset
+ int32_t offset = x;
+ offset = (offset << 1) >> 1; // remove the 31-byte and sign-extend.
+ pc = prev_pc + offset;
+ CHECK(pc);
+ } else {
+ // CHECK(i + 1 < size);
+ if (i + 1 >= size) break;
+ uintptr_t hi = x;
+ uintptr_t lo = compressed[i+1];
+ // Printf("U co[%ld] hi/lo: %lx %lx\n", i, hi, lo);
+ i++;
+ pc = (hi << 32) | lo;
+ if (!pc) break;
+ }
+ // Printf("U pc[%ld] %lx\n", stack->size, pc);
+ stack->trace[stack->size++] = pc;
+ prev_pc = pc;
+ }
+#endif // __WORDSIZE
+}
+
+} // namespace __asan