1//===-- asan_activation.cc --------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is a part of AddressSanitizer, an address sanity checker.
11//
12// ASan activation/deactivation logic.
13//===----------------------------------------------------------------------===//
14
15#include "asan_activation.h"
16#include "asan_allocator.h"
17#include "asan_flags.h"
18#include "asan_internal.h"
19#include "asan_poisoning.h"
20#include "asan_stack.h"
21#include "sanitizer_common/sanitizer_flags.h"
22
23namespace __asan {
24
25static struct AsanDeactivatedFlags {
26  AllocatorOptions allocator_options;
27  int malloc_context_size;
28  bool poison_heap;
29  bool coverage;
30  const char *coverage_dir;
31
32  void RegisterActivationFlags(FlagParser *parser, Flags *f, CommonFlags *cf) {
33#define ASAN_ACTIVATION_FLAG(Type, Name) \
34  RegisterFlag(parser, #Name, "", &f->Name);
35#define COMMON_ACTIVATION_FLAG(Type, Name) \
36  RegisterFlag(parser, #Name, "", &cf->Name);
37#include "asan_activation_flags.inc"
38#undef ASAN_ACTIVATION_FLAG
39#undef COMMON_ACTIVATION_FLAG
40
41    RegisterIncludeFlag(parser, cf);
42  }
43
44  void OverrideFromActivationFlags() {
45    Flags f;
46    CommonFlags cf;
47    FlagParser parser;
48    RegisterActivationFlags(&parser, &f, &cf);
49
50    // Copy the current activation flags.
51    allocator_options.CopyTo(&f, &cf);
52    cf.malloc_context_size = malloc_context_size;
53    f.poison_heap = poison_heap;
54    cf.coverage = coverage;
55    cf.coverage_dir = coverage_dir;
56    cf.verbosity = Verbosity();
57    cf.help = false; // this is activation-specific help
58
59    // Check if activation flags need to be overriden.
60    if (const char *env = GetEnv("ASAN_ACTIVATION_OPTIONS")) {
61      parser.ParseString(env);
62    }
63
64    // Override from getprop asan.options.
65    char buf[100];
66    GetExtraActivationFlags(buf, sizeof(buf));
67    parser.ParseString(buf);
68
69    SetVerbosity(cf.verbosity);
70
71    if (Verbosity()) ReportUnrecognizedFlags();
72
73    if (cf.help) parser.PrintFlagDescriptions();
74
75    allocator_options.SetFrom(&f, &cf);
76    malloc_context_size = cf.malloc_context_size;
77    poison_heap = f.poison_heap;
78    coverage = cf.coverage;
79    coverage_dir = cf.coverage_dir;
80  }
81
82  void Print() {
83    Report(
84        "quarantine_size_mb %d, max_redzone %d, poison_heap %d, "
85        "malloc_context_size %d, alloc_dealloc_mismatch %d, "
86        "allocator_may_return_null %d, coverage %d, coverage_dir %s\n",
87        allocator_options.quarantine_size_mb, allocator_options.max_redzone,
88        poison_heap, malloc_context_size,
89        allocator_options.alloc_dealloc_mismatch,
90        allocator_options.may_return_null, coverage, coverage_dir);
91  }
92} asan_deactivated_flags;
93
94static bool asan_is_deactivated;
95
96void AsanDeactivate() {
97  CHECK(!asan_is_deactivated);
98  VReport(1, "Deactivating ASan\n");
99
100  // Stash runtime state.
101  GetAllocatorOptions(&asan_deactivated_flags.allocator_options);
102  asan_deactivated_flags.malloc_context_size = GetMallocContextSize();
103  asan_deactivated_flags.poison_heap = CanPoisonMemory();
104  asan_deactivated_flags.coverage = common_flags()->coverage;
105  asan_deactivated_flags.coverage_dir = common_flags()->coverage_dir;
106
107  // Deactivate the runtime.
108  SetCanPoisonMemory(false);
109  SetMallocContextSize(1);
110  ReInitializeCoverage(false, nullptr);
111
112  AllocatorOptions disabled = asan_deactivated_flags.allocator_options;
113  disabled.quarantine_size_mb = 0;
114  disabled.min_redzone = 16;  // Redzone must be at least 16 bytes long.
115  disabled.max_redzone = 16;
116  disabled.alloc_dealloc_mismatch = false;
117  disabled.may_return_null = true;
118  ReInitializeAllocator(disabled);
119
120  asan_is_deactivated = true;
121}
122
123void AsanActivate() {
124  if (!asan_is_deactivated) return;
125  VReport(1, "Activating ASan\n");
126
127  asan_deactivated_flags.OverrideFromActivationFlags();
128
129  SetCanPoisonMemory(asan_deactivated_flags.poison_heap);
130  SetMallocContextSize(asan_deactivated_flags.malloc_context_size);
131  ReInitializeCoverage(asan_deactivated_flags.coverage,
132                       asan_deactivated_flags.coverage_dir);
133  ReInitializeAllocator(asan_deactivated_flags.allocator_options);
134
135  asan_is_deactivated = false;
136  if (Verbosity()) {
137    Report("Activated with flags:\n");
138    asan_deactivated_flags.Print();
139  }
140}
141
142}  // namespace __asan
143