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-rw-r--r--lib/sanitizer_common/sanitizer_posix.cpp390
1 files changed, 390 insertions, 0 deletions
diff --git a/lib/sanitizer_common/sanitizer_posix.cpp b/lib/sanitizer_common/sanitizer_posix.cpp
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index 000000000000..d890a3a31773
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+++ b/lib/sanitizer_common/sanitizer_posix.cpp
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+//===-- sanitizer_posix.cpp -----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries and implements POSIX-specific functions from
+// sanitizer_posix.h.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+
+#if SANITIZER_POSIX
+
+#include "sanitizer_common.h"
+#include "sanitizer_file.h"
+#include "sanitizer_flags.h"
+#include "sanitizer_libc.h"
+#include "sanitizer_posix.h"
+#include "sanitizer_procmaps.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/mman.h>
+
+#if SANITIZER_FREEBSD
+// The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
+// that, it was never implemented. So just define it to zero.
+#undef MAP_NORESERVE
+#define MAP_NORESERVE 0
+#endif
+
+namespace __sanitizer {
+
+// ------------- sanitizer_common.h
+uptr GetMmapGranularity() {
+ return GetPageSize();
+}
+
+void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
+ size = RoundUpTo(size, GetPageSizeCached());
+ uptr res = MmapNamed(nullptr, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, mem_type);
+ int reserrno;
+ if (UNLIKELY(internal_iserror(res, &reserrno)))
+ ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno, raw_report);
+ IncreaseTotalMmap(size);
+ return (void *)res;
+}
+
+void UnmapOrDie(void *addr, uptr size) {
+ if (!addr || !size) return;
+ uptr res = internal_munmap(addr, size);
+ if (UNLIKELY(internal_iserror(res))) {
+ Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
+ SanitizerToolName, size, size, addr);
+ CHECK("unable to unmap" && 0);
+ }
+ DecreaseTotalMmap(size);
+}
+
+void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
+ size = RoundUpTo(size, GetPageSizeCached());
+ uptr res = MmapNamed(nullptr, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, mem_type);
+ int reserrno;
+ if (UNLIKELY(internal_iserror(res, &reserrno))) {
+ if (reserrno == ENOMEM)
+ return nullptr;
+ ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
+ }
+ IncreaseTotalMmap(size);
+ return (void *)res;
+}
+
+// We want to map a chunk of address space aligned to 'alignment'.
+// We do it by mapping a bit more and then unmapping redundant pieces.
+// We probably can do it with fewer syscalls in some OS-dependent way.
+void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
+ const char *mem_type) {
+ CHECK(IsPowerOfTwo(size));
+ CHECK(IsPowerOfTwo(alignment));
+ uptr map_size = size + alignment;
+ uptr map_res = (uptr)MmapOrDieOnFatalError(map_size, mem_type);
+ if (UNLIKELY(!map_res))
+ return nullptr;
+ uptr map_end = map_res + map_size;
+ uptr res = map_res;
+ if (!IsAligned(res, alignment)) {
+ res = (map_res + alignment - 1) & ~(alignment - 1);
+ UnmapOrDie((void*)map_res, res - map_res);
+ }
+ uptr end = res + size;
+ if (end != map_end)
+ UnmapOrDie((void*)end, map_end - end);
+ return (void*)res;
+}
+
+void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
+ size = RoundUpTo(size, GetPageSizeCached());
+ uptr p = MmapNamed(nullptr, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON | MAP_NORESERVE, mem_type);
+ int reserrno;
+ if (UNLIKELY(internal_iserror(p, &reserrno)))
+ ReportMmapFailureAndDie(size, mem_type, "allocate noreserve", reserrno);
+ IncreaseTotalMmap(size);
+ return (void *)p;
+}
+
+static void *MmapFixedImpl(uptr fixed_addr, uptr size, bool tolerate_enomem,
+ const char *name) {
+ size = RoundUpTo(size, GetPageSizeCached());
+ fixed_addr = RoundDownTo(fixed_addr, GetPageSizeCached());
+ uptr p = MmapNamed((void *)fixed_addr, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON | MAP_FIXED, name);
+ int reserrno;
+ if (UNLIKELY(internal_iserror(p, &reserrno))) {
+ if (tolerate_enomem && reserrno == ENOMEM)
+ return nullptr;
+ char mem_type[40];
+ internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
+ fixed_addr);
+ ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
+ }
+ IncreaseTotalMmap(size);
+ return (void *)p;
+}
+
+void *MmapFixedOrDie(uptr fixed_addr, uptr size, const char *name) {
+ return MmapFixedImpl(fixed_addr, size, false /*tolerate_enomem*/, name);
+}
+
+void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size, const char *name) {
+ return MmapFixedImpl(fixed_addr, size, true /*tolerate_enomem*/, name);
+}
+
+bool MprotectNoAccess(uptr addr, uptr size) {
+ return 0 == internal_mprotect((void*)addr, size, PROT_NONE);
+}
+
+bool MprotectReadOnly(uptr addr, uptr size) {
+ return 0 == internal_mprotect((void *)addr, size, PROT_READ);
+}
+
+#if !SANITIZER_MAC
+void MprotectMallocZones(void *addr, int prot) {}
+#endif
+
+fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
+ if (ShouldMockFailureToOpen(filename))
+ return kInvalidFd;
+ int flags;
+ switch (mode) {
+ case RdOnly: flags = O_RDONLY; break;
+ case WrOnly: flags = O_WRONLY | O_CREAT | O_TRUNC; break;
+ case RdWr: flags = O_RDWR | O_CREAT; break;
+ }
+ fd_t res = internal_open(filename, flags, 0660);
+ if (internal_iserror(res, errno_p))
+ return kInvalidFd;
+ return ReserveStandardFds(res);
+}
+
+void CloseFile(fd_t fd) {
+ internal_close(fd);
+}
+
+bool ReadFromFile(fd_t fd, void *buff, uptr buff_size, uptr *bytes_read,
+ error_t *error_p) {
+ uptr res = internal_read(fd, buff, buff_size);
+ if (internal_iserror(res, error_p))
+ return false;
+ if (bytes_read)
+ *bytes_read = res;
+ return true;
+}
+
+bool WriteToFile(fd_t fd, const void *buff, uptr buff_size, uptr *bytes_written,
+ error_t *error_p) {
+ uptr res = internal_write(fd, buff, buff_size);
+ if (internal_iserror(res, error_p))
+ return false;
+ if (bytes_written)
+ *bytes_written = res;
+ return true;
+}
+
+void *MapFileToMemory(const char *file_name, uptr *buff_size) {
+ fd_t fd = OpenFile(file_name, RdOnly);
+ CHECK(fd != kInvalidFd);
+ uptr fsize = internal_filesize(fd);
+ CHECK_NE(fsize, (uptr)-1);
+ CHECK_GT(fsize, 0);
+ *buff_size = RoundUpTo(fsize, GetPageSizeCached());
+ uptr map = internal_mmap(nullptr, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ return internal_iserror(map) ? nullptr : (void *)map;
+}
+
+void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset) {
+ uptr flags = MAP_SHARED;
+ if (addr) flags |= MAP_FIXED;
+ uptr p = internal_mmap(addr, size, PROT_READ | PROT_WRITE, flags, fd, offset);
+ int mmap_errno = 0;
+ if (internal_iserror(p, &mmap_errno)) {
+ Printf("could not map writable file (%d, %lld, %zu): %zd, errno: %d\n",
+ fd, (long long)offset, size, p, mmap_errno);
+ return nullptr;
+ }
+ return (void *)p;
+}
+
+static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
+ uptr start2, uptr end2) {
+ CHECK(start1 <= end1);
+ CHECK(start2 <= end2);
+ return (end1 < start2) || (end2 < start1);
+}
+
+// FIXME: this is thread-unsafe, but should not cause problems most of the time.
+// When the shadow is mapped only a single thread usually exists (plus maybe
+// several worker threads on Mac, which aren't expected to map big chunks of
+// memory).
+bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
+ MemoryMappingLayout proc_maps(/*cache_enabled*/true);
+ if (proc_maps.Error())
+ return true; // and hope for the best
+ MemoryMappedSegment segment;
+ while (proc_maps.Next(&segment)) {
+ if (segment.start == segment.end) continue; // Empty range.
+ CHECK_NE(0, segment.end);
+ if (!IntervalsAreSeparate(segment.start, segment.end - 1, range_start,
+ range_end))
+ return false;
+ }
+ return true;
+}
+
+void DumpProcessMap() {
+ MemoryMappingLayout proc_maps(/*cache_enabled*/true);
+ const sptr kBufSize = 4095;
+ char *filename = (char*)MmapOrDie(kBufSize, __func__);
+ MemoryMappedSegment segment(filename, kBufSize);
+ Report("Process memory map follows:\n");
+ while (proc_maps.Next(&segment)) {
+ Printf("\t%p-%p\t%s\n", (void *)segment.start, (void *)segment.end,
+ segment.filename);
+ }
+ Report("End of process memory map.\n");
+ UnmapOrDie(filename, kBufSize);
+}
+
+const char *GetPwd() {
+ return GetEnv("PWD");
+}
+
+bool IsPathSeparator(const char c) {
+ return c == '/';
+}
+
+bool IsAbsolutePath(const char *path) {
+ return path != nullptr && IsPathSeparator(path[0]);
+}
+
+void ReportFile::Write(const char *buffer, uptr length) {
+ SpinMutexLock l(mu);
+ ReopenIfNecessary();
+ internal_write(fd, buffer, length);
+}
+
+bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
+ MemoryMappingLayout proc_maps(/*cache_enabled*/false);
+ InternalScopedString buff(kMaxPathLength);
+ MemoryMappedSegment segment(buff.data(), kMaxPathLength);
+ while (proc_maps.Next(&segment)) {
+ if (segment.IsExecutable() &&
+ internal_strcmp(module, segment.filename) == 0) {
+ *start = segment.start;
+ *end = segment.end;
+ return true;
+ }
+ }
+ return false;
+}
+
+uptr SignalContext::GetAddress() const {
+ auto si = static_cast<const siginfo_t *>(siginfo);
+ return (uptr)si->si_addr;
+}
+
+bool SignalContext::IsMemoryAccess() const {
+ auto si = static_cast<const siginfo_t *>(siginfo);
+ return si->si_signo == SIGSEGV;
+}
+
+int SignalContext::GetType() const {
+ return static_cast<const siginfo_t *>(siginfo)->si_signo;
+}
+
+const char *SignalContext::Describe() const {
+ switch (GetType()) {
+ case SIGFPE:
+ return "FPE";
+ case SIGILL:
+ return "ILL";
+ case SIGABRT:
+ return "ABRT";
+ case SIGSEGV:
+ return "SEGV";
+ case SIGBUS:
+ return "BUS";
+ case SIGTRAP:
+ return "TRAP";
+ }
+ return "UNKNOWN SIGNAL";
+}
+
+fd_t ReserveStandardFds(fd_t fd) {
+ CHECK_GE(fd, 0);
+ if (fd > 2)
+ return fd;
+ bool used[3];
+ internal_memset(used, 0, sizeof(used));
+ while (fd <= 2) {
+ used[fd] = true;
+ fd = internal_dup(fd);
+ }
+ for (int i = 0; i <= 2; ++i)
+ if (used[i])
+ internal_close(i);
+ return fd;
+}
+
+bool ShouldMockFailureToOpen(const char *path) {
+ return common_flags()->test_only_emulate_no_memorymap &&
+ internal_strncmp(path, "/proc/", 6) == 0;
+}
+
+#if SANITIZER_LINUX && !SANITIZER_ANDROID && !SANITIZER_GO
+int GetNamedMappingFd(const char *name, uptr size, int *flags) {
+ if (!common_flags()->decorate_proc_maps || !name)
+ return -1;
+ char shmname[200];
+ CHECK(internal_strlen(name) < sizeof(shmname) - 10);
+ internal_snprintf(shmname, sizeof(shmname), "/dev/shm/%zu [%s]",
+ internal_getpid(), name);
+ int fd = ReserveStandardFds(
+ internal_open(shmname, O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, S_IRWXU));
+ CHECK_GE(fd, 0);
+ int res = internal_ftruncate(fd, size);
+ CHECK_EQ(0, res);
+ res = internal_unlink(shmname);
+ CHECK_EQ(0, res);
+ *flags &= ~(MAP_ANON | MAP_ANONYMOUS);
+ return fd;
+}
+#else
+int GetNamedMappingFd(const char *name, uptr size, int *flags) {
+ return -1;
+}
+#endif
+
+#if SANITIZER_ANDROID
+#define PR_SET_VMA 0x53564d41
+#define PR_SET_VMA_ANON_NAME 0
+void DecorateMapping(uptr addr, uptr size, const char *name) {
+ if (!common_flags()->decorate_proc_maps || !name)
+ return;
+ internal_prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, addr, size, (uptr)name);
+}
+#else
+void DecorateMapping(uptr addr, uptr size, const char *name) {
+}
+#endif
+
+uptr MmapNamed(void *addr, uptr length, int prot, int flags, const char *name) {
+ int fd = GetNamedMappingFd(name, length, &flags);
+ uptr res = internal_mmap(addr, length, prot, flags, fd, 0);
+ if (!internal_iserror(res))
+ DecorateMapping(res, length, name);
+ return res;
+}
+
+
+} // namespace __sanitizer
+
+#endif // SANITIZER_POSIX