xref: /freebsd/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp (revision a0ca4af9455b844c5e094fc1b09b1390ffa979fc)
1 //===-- sanitizer_suppressions.cpp ----------------------------------------===//
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 // Suppression parsing/matching code.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "sanitizer_suppressions.h"
14 
15 #include "sanitizer_allocator_internal.h"
16 #include "sanitizer_common.h"
17 #include "sanitizer_flags.h"
18 #include "sanitizer_file.h"
19 #include "sanitizer_libc.h"
20 #include "sanitizer_placement_new.h"
21 
22 namespace __sanitizer {
23 
24 SuppressionContext::SuppressionContext(const char *suppression_types[],
25                                        int suppression_types_num)
26     : suppression_types_(suppression_types),
27       suppression_types_num_(suppression_types_num),
28       can_parse_(true) {
29   CHECK_LE(suppression_types_num_, kMaxSuppressionTypes);
30   internal_memset(has_suppression_type_, 0, suppression_types_num_);
31 }
32 
33 #if !SANITIZER_FUCHSIA
34 static bool GetPathAssumingFileIsRelativeToExec(const char *file_path,
35                                                 /*out*/char *new_file_path,
36                                                 uptr new_file_path_size) {
37   InternalMmapVector<char> exec(kMaxPathLength);
38   if (ReadBinaryNameCached(exec.data(), exec.size())) {
39     const char *file_name_pos = StripModuleName(exec.data());
40     uptr path_to_exec_len = file_name_pos - exec.data();
41     internal_strncat(new_file_path, exec.data(),
42                      Min(path_to_exec_len, new_file_path_size - 1));
43     internal_strncat(new_file_path, file_path,
44                      new_file_path_size - internal_strlen(new_file_path) - 1);
45     return true;
46   }
47   return false;
48 }
49 
50 static const char *FindFile(const char *file_path,
51                             /*out*/char *new_file_path,
52                             uptr new_file_path_size) {
53   // If we cannot find the file, check if its location is relative to
54   // the location of the executable.
55   if (!FileExists(file_path) && !IsAbsolutePath(file_path) &&
56       GetPathAssumingFileIsRelativeToExec(file_path, new_file_path,
57                                           new_file_path_size)) {
58     return new_file_path;
59   }
60   return file_path;
61 }
62 #else
63 static const char *FindFile(const char *file_path, char *, uptr) {
64   return file_path;
65 }
66 #endif
67 
68 void SuppressionContext::ParseFromFile(const char *filename) {
69   if (filename[0] == '\0')
70     return;
71 
72   InternalMmapVector<char> new_file_path(kMaxPathLength);
73   filename = FindFile(filename, new_file_path.data(), new_file_path.size());
74 
75   // Read the file.
76   VPrintf(1, "%s: reading suppressions file at %s\n",
77           SanitizerToolName, filename);
78   char *file_contents;
79   uptr buffer_size;
80   uptr contents_size;
81   if (!ReadFileToBuffer(filename, &file_contents, &buffer_size,
82                         &contents_size)) {
83     Printf("%s: failed to read suppressions file '%s'\n", SanitizerToolName,
84            filename);
85     Die();
86   }
87 
88   Parse(file_contents);
89   UnmapOrDie(file_contents, contents_size);
90 }
91 
92 bool SuppressionContext::Match(const char *str, const char *type,
93                                Suppression **s) {
94   can_parse_ = false;
95   if (!HasSuppressionType(type))
96     return false;
97   for (uptr i = 0; i < suppressions_.size(); i++) {
98     Suppression &cur = suppressions_[i];
99     if (0 == internal_strcmp(cur.type, type) && TemplateMatch(cur.templ, str)) {
100       *s = &cur;
101       return true;
102     }
103   }
104   return false;
105 }
106 
107 static const char *StripPrefix(const char *str, const char *prefix) {
108   while (*str && *str == *prefix) {
109     str++;
110     prefix++;
111   }
112   if (!*prefix)
113     return str;
114   return 0;
115 }
116 
117 void SuppressionContext::Parse(const char *str) {
118   // Context must not mutate once Match has been called.
119   CHECK(can_parse_);
120   const char *line = str;
121   while (line) {
122     while (line[0] == ' ' || line[0] == '\t')
123       line++;
124     const char *end = internal_strchr(line, '\n');
125     if (end == 0)
126       end = line + internal_strlen(line);
127     if (line != end && line[0] != '#') {
128       const char *end2 = end;
129       while (line != end2 &&
130              (end2[-1] == ' ' || end2[-1] == '\t' || end2[-1] == '\r'))
131         end2--;
132       int type;
133       for (type = 0; type < suppression_types_num_; type++) {
134         const char *next_char = StripPrefix(line, suppression_types_[type]);
135         if (next_char && *next_char == ':') {
136           line = ++next_char;
137           break;
138         }
139       }
140       if (type == suppression_types_num_) {
141         Printf("%s: failed to parse suppressions.\n", SanitizerToolName);
142         Printf("Supported suppression types are:\n");
143         for (type = 0; type < suppression_types_num_; type++)
144           Printf("- %s\n", suppression_types_[type]);
145         Die();
146       }
147       Suppression s;
148       s.type = suppression_types_[type];
149       s.templ = (char*)InternalAlloc(end2 - line + 1);
150       internal_memcpy(s.templ, line, end2 - line);
151       s.templ[end2 - line] = 0;
152       suppressions_.push_back(s);
153       has_suppression_type_[type] = true;
154     }
155     if (end[0] == 0)
156       break;
157     line = end + 1;
158   }
159 }
160 
161 uptr SuppressionContext::SuppressionCount() const {
162   return suppressions_.size();
163 }
164 
165 bool SuppressionContext::HasSuppressionType(const char *type) const {
166   for (int i = 0; i < suppression_types_num_; i++) {
167     if (0 == internal_strcmp(type, suppression_types_[i]))
168       return has_suppression_type_[i];
169   }
170   return false;
171 }
172 
173 const Suppression *SuppressionContext::SuppressionAt(uptr i) const {
174   CHECK_LT(i, suppressions_.size());
175   return &suppressions_[i];
176 }
177 
178 void SuppressionContext::GetMatched(
179     InternalMmapVector<Suppression *> *matched) {
180   for (uptr i = 0; i < suppressions_.size(); i++)
181     if (atomic_load_relaxed(&suppressions_[i].hit_count))
182       matched->push_back(&suppressions_[i]);
183 }
184 
185 }  // namespace __sanitizer
186