1 //===-- sanitizer_posix.cc ------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is shared between AddressSanitizer and ThreadSanitizer
11 // run-time libraries and implements POSIX-specific functions from
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_platform.h"
19 #include "sanitizer_common.h"
20 #include "sanitizer_file.h"
21 #include "sanitizer_flags.h"
22 #include "sanitizer_libc.h"
23 #include "sanitizer_posix.h"
24 #include "sanitizer_procmaps.h"
32 // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
33 // that, it was never implemented. So just define it to zero.
35 #define MAP_NORESERVE 0
38 namespace __sanitizer {
40 // ------------- sanitizer_common.h
41 uptr GetMmapGranularity() {
45 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
46 size = RoundUpTo(size, GetPageSizeCached());
47 uptr res = internal_mmap(nullptr, size,
48 PROT_READ | PROT_WRITE,
49 MAP_PRIVATE | MAP_ANON, -1, 0);
51 if (UNLIKELY(internal_iserror(res, &reserrno)))
52 ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno, raw_report);
53 IncreaseTotalMmap(size);
57 void UnmapOrDie(void *addr, uptr size) {
58 if (!addr || !size) return;
59 uptr res = internal_munmap(addr, size);
60 if (UNLIKELY(internal_iserror(res))) {
61 Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
62 SanitizerToolName, size, size, addr);
63 CHECK("unable to unmap" && 0);
65 DecreaseTotalMmap(size);
68 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
69 size = RoundUpTo(size, GetPageSizeCached());
70 uptr res = internal_mmap(nullptr, size,
71 PROT_READ | PROT_WRITE,
72 MAP_PRIVATE | MAP_ANON, -1, 0);
74 if (UNLIKELY(internal_iserror(res, &reserrno))) {
75 if (reserrno == ENOMEM)
77 ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
79 IncreaseTotalMmap(size);
83 // We want to map a chunk of address space aligned to 'alignment'.
84 // We do it by mapping a bit more and then unmapping redundant pieces.
85 // We probably can do it with fewer syscalls in some OS-dependent way.
86 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
87 const char *mem_type) {
88 CHECK(IsPowerOfTwo(size));
89 CHECK(IsPowerOfTwo(alignment));
90 uptr map_size = size + alignment;
91 uptr map_res = (uptr)MmapOrDieOnFatalError(map_size, mem_type);
92 if (UNLIKELY(!map_res))
94 uptr map_end = map_res + map_size;
96 if (!IsAligned(res, alignment)) {
97 res = (map_res + alignment - 1) & ~(alignment - 1);
98 UnmapOrDie((void*)map_res, res - map_res);
100 uptr end = res + size;
102 UnmapOrDie((void*)end, map_end - end);
106 void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
107 uptr PageSize = GetPageSizeCached();
108 uptr p = internal_mmap(nullptr,
109 RoundUpTo(size, PageSize),
110 PROT_READ | PROT_WRITE,
111 MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
114 if (UNLIKELY(internal_iserror(p, &reserrno)))
115 ReportMmapFailureAndDie(size, mem_type, "allocate noreserve", reserrno);
116 IncreaseTotalMmap(size);
120 void *MmapFixedImpl(uptr fixed_addr, uptr size, bool tolerate_enomem) {
121 uptr PageSize = GetPageSizeCached();
122 uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
123 RoundUpTo(size, PageSize),
124 PROT_READ | PROT_WRITE,
125 MAP_PRIVATE | MAP_ANON | MAP_FIXED,
128 if (UNLIKELY(internal_iserror(p, &reserrno))) {
129 if (tolerate_enomem && reserrno == ENOMEM)
132 internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
134 ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
136 IncreaseTotalMmap(size);
140 void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
141 return MmapFixedImpl(fixed_addr, size, false /*tolerate_enomem*/);
144 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size) {
145 return MmapFixedImpl(fixed_addr, size, true /*tolerate_enomem*/);
148 bool MprotectNoAccess(uptr addr, uptr size) {
149 return 0 == internal_mprotect((void*)addr, size, PROT_NONE);
152 bool MprotectReadOnly(uptr addr, uptr size) {
153 return 0 == internal_mprotect((void *)addr, size, PROT_READ);
157 void MprotectMallocZones(void *addr, int prot) {}
160 fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
161 if (ShouldMockFailureToOpen(filename))
165 case RdOnly: flags = O_RDONLY; break;
166 case WrOnly: flags = O_WRONLY | O_CREAT | O_TRUNC; break;
167 case RdWr: flags = O_RDWR | O_CREAT; break;
169 fd_t res = internal_open(filename, flags, 0660);
170 if (internal_iserror(res, errno_p))
172 return ReserveStandardFds(res);
175 void CloseFile(fd_t fd) {
179 bool ReadFromFile(fd_t fd, void *buff, uptr buff_size, uptr *bytes_read,
181 uptr res = internal_read(fd, buff, buff_size);
182 if (internal_iserror(res, error_p))
189 bool WriteToFile(fd_t fd, const void *buff, uptr buff_size, uptr *bytes_written,
191 uptr res = internal_write(fd, buff, buff_size);
192 if (internal_iserror(res, error_p))
195 *bytes_written = res;
199 void *MapFileToMemory(const char *file_name, uptr *buff_size) {
200 fd_t fd = OpenFile(file_name, RdOnly);
201 CHECK(fd != kInvalidFd);
202 uptr fsize = internal_filesize(fd);
203 CHECK_NE(fsize, (uptr)-1);
205 *buff_size = RoundUpTo(fsize, GetPageSizeCached());
206 uptr map = internal_mmap(nullptr, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
207 return internal_iserror(map) ? nullptr : (void *)map;
210 void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset) {
211 uptr flags = MAP_SHARED;
212 if (addr) flags |= MAP_FIXED;
213 uptr p = internal_mmap(addr, size, PROT_READ | PROT_WRITE, flags, fd, offset);
215 if (internal_iserror(p, &mmap_errno)) {
216 Printf("could not map writable file (%d, %lld, %zu): %zd, errno: %d\n",
217 fd, (long long)offset, size, p, mmap_errno);
223 static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
224 uptr start2, uptr end2) {
225 CHECK(start1 <= end1);
226 CHECK(start2 <= end2);
227 return (end1 < start2) || (end2 < start1);
230 // FIXME: this is thread-unsafe, but should not cause problems most of the time.
231 // When the shadow is mapped only a single thread usually exists (plus maybe
232 // several worker threads on Mac, which aren't expected to map big chunks of
234 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
235 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
236 if (proc_maps.Error())
237 return true; // and hope for the best
238 MemoryMappedSegment segment;
239 while (proc_maps.Next(&segment)) {
240 if (segment.start == segment.end) continue; // Empty range.
241 CHECK_NE(0, segment.end);
242 if (!IntervalsAreSeparate(segment.start, segment.end - 1, range_start,
249 void DumpProcessMap() {
250 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
251 const sptr kBufSize = 4095;
252 char *filename = (char*)MmapOrDie(kBufSize, __func__);
253 MemoryMappedSegment segment(filename, kBufSize);
254 Report("Process memory map follows:\n");
255 while (proc_maps.Next(&segment)) {
256 Printf("\t%p-%p\t%s\n", (void *)segment.start, (void *)segment.end,
259 Report("End of process memory map.\n");
260 UnmapOrDie(filename, kBufSize);
263 const char *GetPwd() {
264 return GetEnv("PWD");
267 bool IsPathSeparator(const char c) {
271 bool IsAbsolutePath(const char *path) {
272 return path != nullptr && IsPathSeparator(path[0]);
275 void ReportFile::Write(const char *buffer, uptr length) {
278 internal_write(fd, buffer, length);
281 bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
282 MemoryMappingLayout proc_maps(/*cache_enabled*/false);
283 InternalScopedString buff(kMaxPathLength);
284 MemoryMappedSegment segment(buff.data(), kMaxPathLength);
285 while (proc_maps.Next(&segment)) {
286 if (segment.IsExecutable() &&
287 internal_strcmp(module, segment.filename) == 0) {
288 *start = segment.start;
296 uptr SignalContext::GetAddress() const {
297 auto si = static_cast<const siginfo_t *>(siginfo);
298 return (uptr)si->si_addr;
301 bool SignalContext::IsMemoryAccess() const {
302 auto si = static_cast<const siginfo_t *>(siginfo);
303 return si->si_signo == SIGSEGV;
306 int SignalContext::GetType() const {
307 return static_cast<const siginfo_t *>(siginfo)->si_signo;
310 const char *SignalContext::Describe() const {
323 return "UNKNOWN SIGNAL";
326 fd_t ReserveStandardFds(fd_t fd) {
331 internal_memset(used, 0, sizeof(used));
334 fd = internal_dup(fd);
336 for (int i = 0; i <= 2; ++i)
342 bool ShouldMockFailureToOpen(const char *path) {
343 return common_flags()->test_only_emulate_no_memorymap &&
344 internal_strncmp(path, "/proc/", 6) == 0;
347 } // namespace __sanitizer
349 #endif // SANITIZER_POSIX