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 // 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 SetVerbosity(cf.verbosity);
65
66 if (Verbosity()) ReportUnrecognizedFlags();
67
68 if (cf.help) parser.PrintFlagDescriptions();
69
70 allocator_options.SetFrom(&f, &cf);
71 malloc_context_size = cf.malloc_context_size;
72 poison_heap = f.poison_heap;
73 coverage = cf.coverage;
74 coverage_dir = cf.coverage_dir;
75 }
76
Print__asan::AsanDeactivatedFlags77 void Print() {
78 Report(
79 "quarantine_size_mb %d, max_redzone %d, poison_heap %d, "
80 "malloc_context_size %d, alloc_dealloc_mismatch %d, "
81 "allocator_may_return_null %d, coverage %d, coverage_dir %s\n",
82 allocator_options.quarantine_size_mb, allocator_options.max_redzone,
83 poison_heap, malloc_context_size,
84 allocator_options.alloc_dealloc_mismatch,
85 allocator_options.may_return_null, coverage, coverage_dir);
86 }
87 } asan_deactivated_flags;
88
89 static bool asan_is_deactivated;
90
AsanDeactivate()91 void AsanDeactivate() {
92 CHECK(!asan_is_deactivated);
93 VReport(1, "Deactivating ASan\n");
94
95 // Stash runtime state.
96 GetAllocatorOptions(&asan_deactivated_flags.allocator_options);
97 asan_deactivated_flags.malloc_context_size = GetMallocContextSize();
98 asan_deactivated_flags.poison_heap = CanPoisonMemory();
99 asan_deactivated_flags.coverage = common_flags()->coverage;
100 asan_deactivated_flags.coverage_dir = common_flags()->coverage_dir;
101
102 // Deactivate the runtime.
103 SetCanPoisonMemory(false);
104 SetMallocContextSize(1);
105 ReInitializeCoverage(false, nullptr);
106
107 AllocatorOptions disabled = asan_deactivated_flags.allocator_options;
108 disabled.quarantine_size_mb = 0;
109 disabled.min_redzone = 16; // Redzone must be at least 16 bytes long.
110 disabled.max_redzone = 16;
111 disabled.alloc_dealloc_mismatch = false;
112 disabled.may_return_null = true;
113 ReInitializeAllocator(disabled);
114
115 asan_is_deactivated = true;
116 }
117
AsanActivate()118 void AsanActivate() {
119 if (!asan_is_deactivated) return;
120 VReport(1, "Activating ASan\n");
121
122 UpdateProcessName();
123
124 asan_deactivated_flags.OverrideFromActivationFlags();
125
126 SetCanPoisonMemory(asan_deactivated_flags.poison_heap);
127 SetMallocContextSize(asan_deactivated_flags.malloc_context_size);
128 ReInitializeCoverage(asan_deactivated_flags.coverage,
129 asan_deactivated_flags.coverage_dir);
130 ReInitializeAllocator(asan_deactivated_flags.allocator_options);
131
132 asan_is_deactivated = false;
133 if (Verbosity()) {
134 Report("Activated with flags:\n");
135 asan_deactivated_flags.Print();
136 }
137 }
138
139 } // namespace __asan
140