1 //===-- sanitizer_common.cc -----------------------------------------------===//
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 shared between AddressSanitizer and ThreadSanitizer
11 // run-time libraries.
12 //===----------------------------------------------------------------------===//
13 
14 #include "sanitizer_common.h"
15 #include "sanitizer_allocator_internal.h"
16 #include "sanitizer_flags.h"
17 #include "sanitizer_libc.h"
18 #include "sanitizer_placement_new.h"
19 #include "sanitizer_stacktrace_printer.h"
20 #include "sanitizer_symbolizer.h"
21 
22 namespace __sanitizer {
23 
24 const char *SanitizerToolName = "SanitizerTool";
25 
26 atomic_uint32_t current_verbosity;
27 
GetPageSizeCached()28 uptr GetPageSizeCached() {
29   static uptr PageSize;
30   if (!PageSize)
31     PageSize = GetPageSize();
32   return PageSize;
33 }
34 
35 StaticSpinMutex report_file_mu;
36 ReportFile report_file = {&report_file_mu, kStderrFd, "", "", 0};
37 
RawWrite(const char * buffer)38 void RawWrite(const char *buffer) {
39   report_file.Write(buffer, internal_strlen(buffer));
40 }
41 
ReopenIfNecessary()42 void ReportFile::ReopenIfNecessary() {
43   mu->CheckLocked();
44   if (fd == kStdoutFd || fd == kStderrFd) return;
45 
46   uptr pid = internal_getpid();
47   // If in tracer, use the parent's file.
48   if (pid == stoptheworld_tracer_pid)
49     pid = stoptheworld_tracer_ppid;
50   if (fd != kInvalidFd) {
51     // If the report file is already opened by the current process,
52     // do nothing. Otherwise the report file was opened by the parent
53     // process, close it now.
54     if (fd_pid == pid)
55       return;
56     else
57       CloseFile(fd);
58   }
59 
60   const char *exe_name = GetProcessName();
61   if (common_flags()->log_exe_name && exe_name) {
62     internal_snprintf(full_path, kMaxPathLength, "%s.%s.%zu", path_prefix,
63                       exe_name, pid);
64   } else {
65     internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
66   }
67   fd = OpenFile(full_path, WrOnly);
68   if (fd == kInvalidFd) {
69     const char *ErrorMsgPrefix = "ERROR: Can't open file: ";
70     WriteToFile(kStderrFd, ErrorMsgPrefix, internal_strlen(ErrorMsgPrefix));
71     WriteToFile(kStderrFd, full_path, internal_strlen(full_path));
72     Die();
73   }
74   fd_pid = pid;
75 }
76 
SetReportPath(const char * path)77 void ReportFile::SetReportPath(const char *path) {
78   if (!path)
79     return;
80   uptr len = internal_strlen(path);
81   if (len > sizeof(path_prefix) - 100) {
82     Report("ERROR: Path is too long: %c%c%c%c%c%c%c%c...\n",
83            path[0], path[1], path[2], path[3],
84            path[4], path[5], path[6], path[7]);
85     Die();
86   }
87 
88   SpinMutexLock l(mu);
89   if (fd != kStdoutFd && fd != kStderrFd && fd != kInvalidFd)
90     CloseFile(fd);
91   fd = kInvalidFd;
92   if (internal_strcmp(path, "stdout") == 0) {
93     fd = kStdoutFd;
94   } else if (internal_strcmp(path, "stderr") == 0) {
95     fd = kStderrFd;
96   } else {
97     internal_snprintf(path_prefix, kMaxPathLength, "%s", path);
98   }
99 }
100 
101 // PID of the tracer task in StopTheWorld. It shares the address space with the
102 // main process, but has a different PID and thus requires special handling.
103 uptr stoptheworld_tracer_pid = 0;
104 // Cached pid of parent process - if the parent process dies, we want to keep
105 // writing to the same log file.
106 uptr stoptheworld_tracer_ppid = 0;
107 
108 static const int kMaxNumOfInternalDieCallbacks = 5;
109 static DieCallbackType InternalDieCallbacks[kMaxNumOfInternalDieCallbacks];
110 
AddDieCallback(DieCallbackType callback)111 bool AddDieCallback(DieCallbackType callback) {
112   for (int i = 0; i < kMaxNumOfInternalDieCallbacks; i++) {
113     if (InternalDieCallbacks[i] == nullptr) {
114       InternalDieCallbacks[i] = callback;
115       return true;
116     }
117   }
118   return false;
119 }
120 
RemoveDieCallback(DieCallbackType callback)121 bool RemoveDieCallback(DieCallbackType callback) {
122   for (int i = 0; i < kMaxNumOfInternalDieCallbacks; i++) {
123     if (InternalDieCallbacks[i] == callback) {
124       internal_memmove(&InternalDieCallbacks[i], &InternalDieCallbacks[i + 1],
125                        sizeof(InternalDieCallbacks[0]) *
126                            (kMaxNumOfInternalDieCallbacks - i - 1));
127       InternalDieCallbacks[kMaxNumOfInternalDieCallbacks - 1] = nullptr;
128       return true;
129     }
130   }
131   return false;
132 }
133 
134 static DieCallbackType UserDieCallback;
SetUserDieCallback(DieCallbackType callback)135 void SetUserDieCallback(DieCallbackType callback) {
136   UserDieCallback = callback;
137 }
138 
Die()139 void NORETURN Die() {
140   if (UserDieCallback)
141     UserDieCallback();
142   for (int i = kMaxNumOfInternalDieCallbacks - 1; i >= 0; i--) {
143     if (InternalDieCallbacks[i])
144       InternalDieCallbacks[i]();
145   }
146   if (common_flags()->abort_on_error)
147     Abort();
148   internal__exit(common_flags()->exitcode);
149 }
150 
151 static CheckFailedCallbackType CheckFailedCallback;
SetCheckFailedCallback(CheckFailedCallbackType callback)152 void SetCheckFailedCallback(CheckFailedCallbackType callback) {
153   CheckFailedCallback = callback;
154 }
155 
CheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)156 void NORETURN CheckFailed(const char *file, int line, const char *cond,
157                           u64 v1, u64 v2) {
158   if (CheckFailedCallback) {
159     CheckFailedCallback(file, line, cond, v1, v2);
160   }
161   Report("Sanitizer CHECK failed: %s:%d %s (%lld, %lld)\n", file, line, cond,
162                                                             v1, v2);
163   Die();
164 }
165 
ReportMmapFailureAndDie(uptr size,const char * mem_type,const char * mmap_type,error_t err,bool raw_report)166 void NORETURN ReportMmapFailureAndDie(uptr size, const char *mem_type,
167                                       const char *mmap_type, error_t err,
168                                       bool raw_report) {
169   static int recursion_count;
170   if (raw_report || recursion_count) {
171     // If raw report is requested or we went into recursion, just die.
172     // The Report() and CHECK calls below may call mmap recursively and fail.
173     RawWrite("ERROR: Failed to mmap\n");
174     Die();
175   }
176   recursion_count++;
177   Report("ERROR: %s failed to "
178          "%s 0x%zx (%zd) bytes of %s (error code: %d)\n",
179          SanitizerToolName, mmap_type, size, size, mem_type, err);
180 #ifndef SANITIZER_GO
181   DumpProcessMap();
182 #endif
183   UNREACHABLE("unable to mmap");
184 }
185 
ReadFileToBuffer(const char * file_name,char ** buff,uptr * buff_size,uptr * read_len,uptr max_len,error_t * errno_p)186 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
187                       uptr *read_len, uptr max_len, error_t *errno_p) {
188   uptr PageSize = GetPageSizeCached();
189   uptr kMinFileLen = PageSize;
190   *buff = nullptr;
191   *buff_size = 0;
192   *read_len = 0;
193   // The files we usually open are not seekable, so try different buffer sizes.
194   for (uptr size = kMinFileLen; size <= max_len; size *= 2) {
195     fd_t fd = OpenFile(file_name, RdOnly, errno_p);
196     if (fd == kInvalidFd) return false;
197     UnmapOrDie(*buff, *buff_size);
198     *buff = (char*)MmapOrDie(size, __func__);
199     *buff_size = size;
200     *read_len = 0;
201     // Read up to one page at a time.
202     bool reached_eof = false;
203     while (*read_len + PageSize <= size) {
204       uptr just_read;
205       if (!ReadFromFile(fd, *buff + *read_len, PageSize, &just_read, errno_p)) {
206         UnmapOrDie(*buff, *buff_size);
207         return false;
208       }
209       if (just_read == 0) {
210         reached_eof = true;
211         break;
212       }
213       *read_len += just_read;
214     }
215     CloseFile(fd);
216     if (reached_eof)  // We've read the whole file.
217       break;
218   }
219   return true;
220 }
221 
222 typedef bool UptrComparisonFunction(const uptr &a, const uptr &b);
223 
224 template<class T>
CompareLess(const T & a,const T & b)225 static inline bool CompareLess(const T &a, const T &b) {
226   return a < b;
227 }
228 
SortArray(uptr * array,uptr size)229 void SortArray(uptr *array, uptr size) {
230   InternalSort<uptr*, UptrComparisonFunction>(&array, size, CompareLess);
231 }
232 
233 // We want to map a chunk of address space aligned to 'alignment'.
234 // We do it by maping a bit more and then unmaping redundant pieces.
235 // We probably can do it with fewer syscalls in some OS-dependent way.
MmapAlignedOrDie(uptr size,uptr alignment,const char * mem_type)236 void *MmapAlignedOrDie(uptr size, uptr alignment, const char *mem_type) {
237 // uptr PageSize = GetPageSizeCached();
238   CHECK(IsPowerOfTwo(size));
239   CHECK(IsPowerOfTwo(alignment));
240   uptr map_size = size + alignment;
241   uptr map_res = (uptr)MmapOrDie(map_size, mem_type);
242   uptr map_end = map_res + map_size;
243   uptr res = map_res;
244   if (res & (alignment - 1))  // Not aligned.
245     res = (map_res + alignment) & ~(alignment - 1);
246   uptr end = res + size;
247   if (res != map_res)
248     UnmapOrDie((void*)map_res, res - map_res);
249   if (end != map_end)
250     UnmapOrDie((void*)end, map_end - end);
251   return (void*)res;
252 }
253 
StripPathPrefix(const char * filepath,const char * strip_path_prefix)254 const char *StripPathPrefix(const char *filepath,
255                             const char *strip_path_prefix) {
256   if (!filepath) return nullptr;
257   if (!strip_path_prefix) return filepath;
258   const char *res = filepath;
259   if (const char *pos = internal_strstr(filepath, strip_path_prefix))
260     res = pos + internal_strlen(strip_path_prefix);
261   if (res[0] == '.' && res[1] == '/')
262     res += 2;
263   return res;
264 }
265 
StripModuleName(const char * module)266 const char *StripModuleName(const char *module) {
267   if (!module)
268     return nullptr;
269   if (SANITIZER_WINDOWS) {
270     // On Windows, both slash and backslash are possible.
271     // Pick the one that goes last.
272     if (const char *bslash_pos = internal_strrchr(module, '\\'))
273       return StripModuleName(bslash_pos + 1);
274   }
275   if (const char *slash_pos = internal_strrchr(module, '/')) {
276     return slash_pos + 1;
277   }
278   return module;
279 }
280 
ReportErrorSummary(const char * error_message)281 void ReportErrorSummary(const char *error_message) {
282   if (!common_flags()->print_summary)
283     return;
284   InternalScopedString buff(kMaxSummaryLength);
285   buff.append("SUMMARY: %s: %s", SanitizerToolName, error_message);
286   __sanitizer_report_error_summary(buff.data());
287 }
288 
289 #ifndef SANITIZER_GO
ReportErrorSummary(const char * error_type,const AddressInfo & info)290 void ReportErrorSummary(const char *error_type, const AddressInfo &info) {
291   if (!common_flags()->print_summary)
292     return;
293   InternalScopedString buff(kMaxSummaryLength);
294   buff.append("%s ", error_type);
295   RenderFrame(&buff, "%L %F", 0, info, common_flags()->symbolize_vs_style,
296               common_flags()->strip_path_prefix);
297   ReportErrorSummary(buff.data());
298 }
299 #endif
300 
301 // Removes the ANSI escape sequences from the input string (in-place).
RemoveANSIEscapeSequencesFromString(char * str)302 void RemoveANSIEscapeSequencesFromString(char *str) {
303   if (!str)
304     return;
305 
306   // We are going to remove the escape sequences in place.
307   char *s = str;
308   char *z = str;
309   while (*s != '\0') {
310     CHECK_GE(s, z);
311     // Skip over ANSI escape sequences with pointer 's'.
312     if (*s == '\033' && *(s + 1) == '[') {
313       s = internal_strchrnul(s, 'm');
314       if (*s == '\0') {
315         break;
316       }
317       s++;
318       continue;
319     }
320     // 's' now points at a character we want to keep. Copy over the buffer
321     // content if the escape sequence has been perviously skipped andadvance
322     // both pointers.
323     if (s != z)
324       *z = *s;
325 
326     // If we have not seen an escape sequence, just advance both pointers.
327     z++;
328     s++;
329   }
330 
331   // Null terminate the string.
332   *z = '\0';
333 }
334 
set(const char * module_name,uptr base_address)335 void LoadedModule::set(const char *module_name, uptr base_address) {
336   clear();
337   full_name_ = internal_strdup(module_name);
338   base_address_ = base_address;
339 }
340 
clear()341 void LoadedModule::clear() {
342   InternalFree(full_name_);
343   full_name_ = nullptr;
344   while (!ranges_.empty()) {
345     AddressRange *r = ranges_.front();
346     ranges_.pop_front();
347     InternalFree(r);
348   }
349 }
350 
addAddressRange(uptr beg,uptr end,bool executable)351 void LoadedModule::addAddressRange(uptr beg, uptr end, bool executable) {
352   void *mem = InternalAlloc(sizeof(AddressRange));
353   AddressRange *r = new(mem) AddressRange(beg, end, executable);
354   ranges_.push_back(r);
355 }
356 
containsAddress(uptr address) const357 bool LoadedModule::containsAddress(uptr address) const {
358   for (Iterator iter = ranges(); iter.hasNext();) {
359     const AddressRange *r = iter.next();
360     if (r->beg <= address && address < r->end)
361       return true;
362   }
363   return false;
364 }
365 
366 static atomic_uintptr_t g_total_mmaped;
367 
IncreaseTotalMmap(uptr size)368 void IncreaseTotalMmap(uptr size) {
369   if (!common_flags()->mmap_limit_mb) return;
370   uptr total_mmaped =
371       atomic_fetch_add(&g_total_mmaped, size, memory_order_relaxed) + size;
372   // Since for now mmap_limit_mb is not a user-facing flag, just kill
373   // a program. Use RAW_CHECK to avoid extra mmaps in reporting.
374   RAW_CHECK((total_mmaped >> 20) < common_flags()->mmap_limit_mb);
375 }
376 
DecreaseTotalMmap(uptr size)377 void DecreaseTotalMmap(uptr size) {
378   if (!common_flags()->mmap_limit_mb) return;
379   atomic_fetch_sub(&g_total_mmaped, size, memory_order_relaxed);
380 }
381 
TemplateMatch(const char * templ,const char * str)382 bool TemplateMatch(const char *templ, const char *str) {
383   if ((!str) || str[0] == 0)
384     return false;
385   bool start = false;
386   if (templ && templ[0] == '^') {
387     start = true;
388     templ++;
389   }
390   bool asterisk = false;
391   while (templ && templ[0]) {
392     if (templ[0] == '*') {
393       templ++;
394       start = false;
395       asterisk = true;
396       continue;
397     }
398     if (templ[0] == '$')
399       return str[0] == 0 || asterisk;
400     if (str[0] == 0)
401       return false;
402     char *tpos = (char*)internal_strchr(templ, '*');
403     char *tpos1 = (char*)internal_strchr(templ, '$');
404     if ((!tpos) || (tpos1 && tpos1 < tpos))
405       tpos = tpos1;
406     if (tpos)
407       tpos[0] = 0;
408     const char *str0 = str;
409     const char *spos = internal_strstr(str, templ);
410     str = spos + internal_strlen(templ);
411     templ = tpos;
412     if (tpos)
413       tpos[0] = tpos == tpos1 ? '$' : '*';
414     if (!spos)
415       return false;
416     if (start && spos != str0)
417       return false;
418     start = false;
419     asterisk = false;
420   }
421   return true;
422 }
423 
424 static const char kPathSeparator = SANITIZER_WINDOWS ? ';' : ':';
425 
FindPathToBinary(const char * name)426 char *FindPathToBinary(const char *name) {
427   const char *path = GetEnv("PATH");
428   if (!path)
429     return nullptr;
430   uptr name_len = internal_strlen(name);
431   InternalScopedBuffer<char> buffer(kMaxPathLength);
432   const char *beg = path;
433   while (true) {
434     const char *end = internal_strchrnul(beg, kPathSeparator);
435     uptr prefix_len = end - beg;
436     if (prefix_len + name_len + 2 <= kMaxPathLength) {
437       internal_memcpy(buffer.data(), beg, prefix_len);
438       buffer[prefix_len] = '/';
439       internal_memcpy(&buffer[prefix_len + 1], name, name_len);
440       buffer[prefix_len + 1 + name_len] = '\0';
441       if (FileExists(buffer.data()))
442         return internal_strdup(buffer.data());
443     }
444     if (*end == '\0') break;
445     beg = end + 1;
446   }
447   return nullptr;
448 }
449 
450 static char binary_name_cache_str[kMaxPathLength];
451 static char process_name_cache_str[kMaxPathLength];
452 
GetProcessName()453 const char *GetProcessName() {
454   return process_name_cache_str;
455 }
456 
ReadProcessName(char * buf,uptr buf_len)457 static uptr ReadProcessName(/*out*/ char *buf, uptr buf_len) {
458   ReadLongProcessName(buf, buf_len);
459   char *s = const_cast<char *>(StripModuleName(buf));
460   uptr len = internal_strlen(s);
461   if (s != buf) {
462     internal_memmove(buf, s, len);
463     buf[len] = '\0';
464   }
465   return len;
466 }
467 
UpdateProcessName()468 void UpdateProcessName() {
469   ReadProcessName(process_name_cache_str, sizeof(process_name_cache_str));
470 }
471 
472 // Call once to make sure that binary_name_cache_str is initialized
CacheBinaryName()473 void CacheBinaryName() {
474   if (binary_name_cache_str[0] != '\0')
475     return;
476   ReadBinaryName(binary_name_cache_str, sizeof(binary_name_cache_str));
477   ReadProcessName(process_name_cache_str, sizeof(process_name_cache_str));
478 }
479 
ReadBinaryNameCached(char * buf,uptr buf_len)480 uptr ReadBinaryNameCached(/*out*/char *buf, uptr buf_len) {
481   CacheBinaryName();
482   uptr name_len = internal_strlen(binary_name_cache_str);
483   name_len = (name_len < buf_len - 1) ? name_len : buf_len - 1;
484   if (buf_len == 0)
485     return 0;
486   internal_memcpy(buf, binary_name_cache_str, name_len);
487   buf[name_len] = '\0';
488   return name_len;
489 }
490 
491 } // namespace __sanitizer
492 
493 using namespace __sanitizer;  // NOLINT
494 
495 extern "C" {
__sanitizer_set_report_path(const char * path)496 void __sanitizer_set_report_path(const char *path) {
497   report_file.SetReportPath(path);
498 }
499 
__sanitizer_report_error_summary(const char * error_summary)500 void __sanitizer_report_error_summary(const char *error_summary) {
501   Printf("%s\n", error_summary);
502 }
503 
504 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_set_death_callback(void (* callback)(void))505 void __sanitizer_set_death_callback(void (*callback)(void)) {
506   SetUserDieCallback(callback);
507 }
508 } // extern "C"
509