1//===-- backtrace_sanitizer_common.cpp --------------------------*- C++ -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8 9#include <assert.h> 10#include <stddef.h> 11#include <stdint.h> 12#include <string.h> 13 14#include "gwp_asan/optional/backtrace.h" 15#include "gwp_asan/options.h" 16#include "sanitizer_common/sanitizer_common.h" 17#include "sanitizer_common/sanitizer_flag_parser.h" 18#include "sanitizer_common/sanitizer_flags.h" 19#include "sanitizer_common/sanitizer_stacktrace.h" 20 21void __sanitizer::BufferedStackTrace::UnwindImpl(uptr pc, uptr bp, 22 void *context, 23 bool request_fast, 24 u32 max_depth) { 25 if (!StackTrace::WillUseFastUnwind(request_fast)) { 26 return Unwind(max_depth, pc, bp, context, 0, 0, request_fast); 27 } 28 Unwind(max_depth, pc, 0, context, 0, 0, false); 29} 30 31namespace { 32size_t Backtrace(uintptr_t *TraceBuffer, size_t Size) { 33 __sanitizer::BufferedStackTrace Trace; 34 Trace.Reset(); 35 if (Size > __sanitizer::kStackTraceMax) 36 Size = __sanitizer::kStackTraceMax; 37 38 Trace.Unwind((__sanitizer::uptr)__builtin_return_address(0), 39 (__sanitizer::uptr)__builtin_frame_address(0), 40 /* ucontext */ nullptr, 41 /* fast unwind */ true, Size - 1); 42 43 memcpy(TraceBuffer, Trace.trace, Trace.size * sizeof(uintptr_t)); 44 return Trace.size; 45} 46 47static void PrintBacktrace(uintptr_t *Trace, size_t TraceLength, 48 gwp_asan::options::Printf_t Printf) { 49 __sanitizer::StackTrace StackTrace; 50 StackTrace.trace = reinterpret_cast<__sanitizer::uptr *>(Trace); 51 StackTrace.size = TraceLength; 52 53 if (StackTrace.size == 0) { 54 Printf(" <unknown (does your allocator support backtracing?)>\n\n"); 55 return; 56 } 57 58 StackTrace.Print(); 59} 60} // anonymous namespace 61 62namespace gwp_asan { 63namespace options { 64// This function is thread-compatible. It must be synchronised in respect to any 65// other calls to getBacktraceFunction(), calls to getPrintBacktraceFunction(), 66// and calls to either of the functions that they return. Furthermore, this may 67// require synchronisation with any calls to sanitizer_common that use flags. 68// Generally, this function will be called during the initialisation of the 69// allocator, which is done in a thread-compatible manner. 70Backtrace_t getBacktraceFunction() { 71 // The unwinder requires the default flags to be set. 72 __sanitizer::SetCommonFlagsDefaults(); 73 __sanitizer::InitializeCommonFlags(); 74 return Backtrace; 75} 76PrintBacktrace_t getPrintBacktraceFunction() { return PrintBacktrace; } 77} // namespace options 78} // namespace gwp_asan 79