Retro68/gcc/libsanitizer/sanitizer_common/sanitizer_posix.cc
2015-08-28 17:33:40 +02:00

340 lines
11 KiB
C++

//===-- sanitizer_posix.cc ------------------------------------------------===//
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is shared between AddressSanitizer and ThreadSanitizer
// run-time libraries and implements POSIX-specific functions from
// sanitizer_libc.h.
//===----------------------------------------------------------------------===//
#include "sanitizer_platform.h"
#if SANITIZER_POSIX
#include "sanitizer_common.h"
#include "sanitizer_libc.h"
#include "sanitizer_procmaps.h"
#include "sanitizer_stacktrace.h"
#include <sys/mman.h>
#if SANITIZER_LINUX
#include <sys/utsname.h>
#endif
#if SANITIZER_LINUX && !SANITIZER_ANDROID
#include <sys/personality.h>
#endif
namespace __sanitizer {
// ------------- sanitizer_common.h
uptr GetMmapGranularity() {
return GetPageSize();
}
#if SANITIZER_WORDSIZE == 32
// Take care of unusable kernel area in top gigabyte.
static uptr GetKernelAreaSize() {
#if SANITIZER_LINUX
const uptr gbyte = 1UL << 30;
// Firstly check if there are writable segments
// mapped to top gigabyte (e.g. stack).
MemoryMappingLayout proc_maps(/*cache_enabled*/true);
uptr end, prot;
while (proc_maps.Next(/*start*/0, &end,
/*offset*/0, /*filename*/0,
/*filename_size*/0, &prot)) {
if ((end >= 3 * gbyte)
&& (prot & MemoryMappingLayout::kProtectionWrite) != 0)
return 0;
}
#if !SANITIZER_ANDROID
// Even if nothing is mapped, top Gb may still be accessible
// if we are running on 64-bit kernel.
// Uname may report misleading results if personality type
// is modified (e.g. under schroot) so check this as well.
struct utsname uname_info;
int pers = personality(0xffffffffUL);
if (!(pers & PER_MASK)
&& uname(&uname_info) == 0
&& internal_strstr(uname_info.machine, "64"))
return 0;
#endif // SANITIZER_ANDROID
// Top gigabyte is reserved for kernel.
return gbyte;
#else
return 0;
#endif // SANITIZER_LINUX
}
#endif // SANITIZER_WORDSIZE == 32
uptr GetMaxVirtualAddress() {
#if SANITIZER_WORDSIZE == 64
# if defined(__powerpc64__) || defined(__aarch64__)
// On PowerPC64 we have two different address space layouts: 44- and 46-bit.
// We somehow need to figure out which one we are using now and choose
// one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
// Note that with 'ulimit -s unlimited' the stack is moved away from the top
// of the address space, so simply checking the stack address is not enough.
// This should (does) work for both PowerPC64 Endian modes.
// Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit.
return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1;
# elif defined(__mips64)
return (1ULL << 40) - 1;
# else
return (1ULL << 47) - 1; // 0x00007fffffffffffUL;
# endif
#else // SANITIZER_WORDSIZE == 32
uptr res = (1ULL << 32) - 1; // 0xffffffff;
if (!common_flags()->full_address_space)
res -= GetKernelAreaSize();
CHECK_LT(reinterpret_cast<uptr>(&res), res);
return res;
#endif // SANITIZER_WORDSIZE
}
void *MmapOrDie(uptr size, const char *mem_type) {
size = RoundUpTo(size, GetPageSizeCached());
uptr res = internal_mmap(0, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON, -1, 0);
int reserrno;
if (internal_iserror(res, &reserrno)) {
static int recursion_count;
if (recursion_count) {
// The Report() and CHECK calls below may call mmap recursively and fail.
// If we went into recursion, just die.
RawWrite("ERROR: Failed to mmap\n");
Die();
}
recursion_count++;
Report("ERROR: %s failed to "
"allocate 0x%zx (%zd) bytes of %s (errno: %d)\n",
SanitizerToolName, size, size, mem_type, reserrno);
DumpProcessMap();
CHECK("unable to mmap" && 0);
}
IncreaseTotalMmap(size);
return (void *)res;
}
void UnmapOrDie(void *addr, uptr size) {
if (!addr || !size) return;
uptr res = internal_munmap(addr, size);
if (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 *MmapNoReserveOrDie(uptr size, const char *mem_type) {
uptr PageSize = GetPageSizeCached();
uptr p = internal_mmap(0,
RoundUpTo(size, PageSize),
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
-1, 0);
int reserrno;
if (internal_iserror(p, &reserrno)) {
Report("ERROR: %s failed to "
"allocate noreserve 0x%zx (%zd) bytes for '%s' (errno: %d)\n",
SanitizerToolName, size, size, mem_type, reserrno);
CHECK("unable to mmap" && 0);
}
IncreaseTotalMmap(size);
return (void *)p;
}
void *MmapFixedNoReserve(uptr fixed_addr, uptr size) {
uptr PageSize = GetPageSizeCached();
uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
RoundUpTo(size, PageSize),
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE,
-1, 0);
int reserrno;
if (internal_iserror(p, &reserrno))
Report("ERROR: %s failed to "
"allocate 0x%zx (%zd) bytes at address %zx (errno: %d)\n",
SanitizerToolName, size, size, fixed_addr, reserrno);
IncreaseTotalMmap(size);
return (void *)p;
}
void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
uptr PageSize = GetPageSizeCached();
uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
RoundUpTo(size, PageSize),
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON | MAP_FIXED,
-1, 0);
int reserrno;
if (internal_iserror(p, &reserrno)) {
Report("ERROR: %s failed to "
"allocate 0x%zx (%zd) bytes at address %zx (errno: %d)\n",
SanitizerToolName, size, size, fixed_addr, reserrno);
CHECK("unable to mmap" && 0);
}
IncreaseTotalMmap(size);
return (void *)p;
}
void *Mprotect(uptr fixed_addr, uptr size) {
return (void *)internal_mmap((void*)fixed_addr, size,
PROT_NONE,
MAP_PRIVATE | MAP_ANON | MAP_FIXED |
MAP_NORESERVE, -1, 0);
}
void *MapFileToMemory(const char *file_name, uptr *buff_size) {
uptr openrv = OpenFile(file_name, false);
CHECK(!internal_iserror(openrv));
fd_t fd = openrv;
uptr fsize = internal_filesize(fd);
CHECK_NE(fsize, (uptr)-1);
CHECK_GT(fsize, 0);
*buff_size = RoundUpTo(fsize, GetPageSizeCached());
uptr map = internal_mmap(0, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
return internal_iserror(map) ? 0 : (void *)map;
}
void *MapWritableFileToMemory(void *addr, uptr size, uptr fd, uptr offset) {
uptr flags = MAP_SHARED;
if (addr) flags |= MAP_FIXED;
uptr p = internal_mmap(addr, size, PROT_READ | PROT_WRITE, flags, fd, offset);
if (internal_iserror(p)) {
Printf("could not map writable file (%zd, %zu, %zu): %zd\n", fd, offset,
size, p);
return 0;
}
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);
uptr start, end;
while (proc_maps.Next(&start, &end,
/*offset*/0, /*filename*/0, /*filename_size*/0,
/*protection*/0)) {
if (!IntervalsAreSeparate(start, end, range_start, range_end))
return false;
}
return true;
}
void DumpProcessMap() {
MemoryMappingLayout proc_maps(/*cache_enabled*/true);
uptr start, end;
const sptr kBufSize = 4095;
char *filename = (char*)MmapOrDie(kBufSize, __func__);
Report("Process memory map follows:\n");
while (proc_maps.Next(&start, &end, /* file_offset */0,
filename, kBufSize, /* protection */0)) {
Printf("\t%p-%p\t%s\n", (void*)start, (void*)end, filename);
}
Report("End of process memory map.\n");
UnmapOrDie(filename, kBufSize);
}
const char *GetPwd() {
return GetEnv("PWD");
}
char *FindPathToBinary(const char *name) {
const char *path = GetEnv("PATH");
if (!path)
return 0;
uptr name_len = internal_strlen(name);
InternalScopedBuffer<char> buffer(kMaxPathLength);
const char *beg = path;
while (true) {
const char *end = internal_strchrnul(beg, ':');
uptr prefix_len = end - beg;
if (prefix_len + name_len + 2 <= kMaxPathLength) {
internal_memcpy(buffer.data(), beg, prefix_len);
buffer[prefix_len] = '/';
internal_memcpy(&buffer[prefix_len + 1], name, name_len);
buffer[prefix_len + 1 + name_len] = '\0';
if (FileExists(buffer.data()))
return internal_strdup(buffer.data());
}
if (*end == '\0') break;
beg = end + 1;
}
return 0;
}
void MaybeOpenReportFile() {
if (!log_to_file) return;
uptr pid = internal_getpid();
// If in tracer, use the parent's file.
if (pid == stoptheworld_tracer_pid)
pid = stoptheworld_tracer_ppid;
if (report_fd_pid == pid) return;
InternalScopedBuffer<char> report_path_full(4096);
internal_snprintf(report_path_full.data(), report_path_full.size(),
"%s.%zu", report_path_prefix, pid);
uptr openrv = OpenFile(report_path_full.data(), true);
if (internal_iserror(openrv)) {
report_fd = kStderrFd;
log_to_file = false;
Report("ERROR: Can't open file: %s\n", report_path_full.data());
Die();
}
if (report_fd != kInvalidFd) {
// We're in the child. Close the parent's log.
internal_close(report_fd);
}
report_fd = openrv;
report_fd_pid = pid;
}
void RawWrite(const char *buffer) {
static const char *kRawWriteError =
"RawWrite can't output requested buffer!\n";
uptr length = (uptr)internal_strlen(buffer);
MaybeOpenReportFile();
if (length != internal_write(report_fd, buffer, length)) {
internal_write(report_fd, kRawWriteError, internal_strlen(kRawWriteError));
Die();
}
}
bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
uptr s, e, off, prot;
InternalScopedString buff(4096);
MemoryMappingLayout proc_maps(/*cache_enabled*/false);
while (proc_maps.Next(&s, &e, &off, buff.data(), buff.size(), &prot)) {
if ((prot & MemoryMappingLayout::kProtectionExecute) != 0
&& internal_strcmp(module, buff.data()) == 0) {
*start = s;
*end = e;
return true;
}
}
return false;
}
} // namespace __sanitizer
#endif // SANITIZER_POSIX