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
23 namespace __asan {
24
25 static struct AsanDeactivatedFlags {
26 AllocatorOptions allocator_options;
27 int malloc_context_size;
28 bool poison_heap;
29 bool coverage;
30 const char *coverage_dir;
31
RegisterActivationFlags__asan::AsanDeactivatedFlags32 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 RegisterIncludeFlags(parser, cf);
42 }
43
OverrideFromActivationFlags__asan::AsanDeactivatedFlags44 void OverrideFromActivationFlags() {
45 Flags f;
46 CommonFlags cf;
47 FlagParser parser;
48 RegisterActivationFlags(&parser, &f, &cf);
49
50 cf.SetDefaults();
51 // Copy the current activation flags.
52 allocator_options.CopyTo(&f, &cf);
53 cf.malloc_context_size = malloc_context_size;
54 f.poison_heap = poison_heap;
55 cf.coverage = coverage;
56 cf.coverage_dir = coverage_dir;
57 cf.verbosity = Verbosity();
58 cf.help = false; // this is activation-specific help
59
60 // Check if activation flags need to be overriden.
61 if (const char *env = GetEnv("ASAN_ACTIVATION_OPTIONS")) {
62 parser.ParseString(env);
63 }
64
65 InitializeCommonFlags(&cf);
66
67 if (Verbosity()) ReportUnrecognizedFlags();
68
69 if (cf.help) parser.PrintFlagDescriptions();
70
71 allocator_options.SetFrom(&f, &cf);
72 malloc_context_size = cf.malloc_context_size;
73 poison_heap = f.poison_heap;
74 coverage = cf.coverage;
75 coverage_dir = cf.coverage_dir;
76 }
77
Print__asan::AsanDeactivatedFlags78 void Print() {
79 Report(
80 "quarantine_size_mb %d, max_redzone %d, poison_heap %d, "
81 "malloc_context_size %d, alloc_dealloc_mismatch %d, "
82 "allocator_may_return_null %d, coverage %d, coverage_dir %s\n",
83 allocator_options.quarantine_size_mb, allocator_options.max_redzone,
84 poison_heap, malloc_context_size,
85 allocator_options.alloc_dealloc_mismatch,
86 allocator_options.may_return_null, coverage, coverage_dir);
87 }
88 } asan_deactivated_flags;
89
90 static bool asan_is_deactivated;
91
AsanDeactivate()92 void AsanDeactivate() {
93 CHECK(!asan_is_deactivated);
94 VReport(1, "Deactivating ASan\n");
95
96 // Stash runtime state.
97 GetAllocatorOptions(&asan_deactivated_flags.allocator_options);
98 asan_deactivated_flags.malloc_context_size = GetMallocContextSize();
99 asan_deactivated_flags.poison_heap = CanPoisonMemory();
100 asan_deactivated_flags.coverage = common_flags()->coverage;
101 asan_deactivated_flags.coverage_dir = common_flags()->coverage_dir;
102
103 // Deactivate the runtime.
104 SetCanPoisonMemory(false);
105 SetMallocContextSize(1);
106 ReInitializeCoverage(false, nullptr);
107
108 AllocatorOptions disabled = asan_deactivated_flags.allocator_options;
109 disabled.quarantine_size_mb = 0;
110 disabled.min_redzone = 16; // Redzone must be at least 16 bytes long.
111 disabled.max_redzone = 16;
112 disabled.alloc_dealloc_mismatch = false;
113 disabled.may_return_null = true;
114 ReInitializeAllocator(disabled);
115
116 asan_is_deactivated = true;
117 }
118
AsanActivate()119 void AsanActivate() {
120 if (!asan_is_deactivated) return;
121 VReport(1, "Activating ASan\n");
122
123 UpdateProcessName();
124
125 asan_deactivated_flags.OverrideFromActivationFlags();
126
127 SetCanPoisonMemory(asan_deactivated_flags.poison_heap);
128 SetMallocContextSize(asan_deactivated_flags.malloc_context_size);
129 ReInitializeCoverage(asan_deactivated_flags.coverage,
130 asan_deactivated_flags.coverage_dir);
131 ReInitializeAllocator(asan_deactivated_flags.allocator_options);
132
133 asan_is_deactivated = false;
134 if (Verbosity()) {
135 Report("Activated with flags:\n");
136 asan_deactivated_flags.Print();
137 }
138 }
139
140 } // namespace __asan
141