llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_procmaps.h

124 lines
4.1 KiB
C++

//===-- sanitizer_procmaps.h ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// 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.
//
// Information about the process mappings.
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_PROCMAPS_H
#define SANITIZER_PROCMAPS_H
#include "sanitizer_internal_defs.h"
#include "sanitizer_mutex.h"
namespace __sanitizer {
#ifdef _WIN32
class MemoryMappingLayout {
public:
MemoryMappingLayout() {}
bool GetObjectNameAndOffset(uptr addr, uptr *offset,
char filename[], uptr filename_size,
uptr *protection) {
UNIMPLEMENTED();
}
};
#else // _WIN32
#if defined(__linux__)
struct ProcSelfMapsBuff {
char *data;
uptr mmaped_size;
uptr len;
};
#endif // defined(__linux__)
class MemoryMappingLayout {
public:
MemoryMappingLayout();
bool Next(uptr *start, uptr *end, uptr *offset,
char filename[], uptr filename_size, uptr *protection);
void Reset();
// Gets the object file name and the offset in that object for a given
// address 'addr'. Returns true on success.
bool GetObjectNameAndOffset(uptr addr, uptr *offset,
char filename[], uptr filename_size,
uptr *protection);
// In some cases, e.g. when running under a sandbox on Linux, ASan is unable
// to obtain the memory mappings. It should fall back to pre-cached data
// instead of aborting.
static void CacheMemoryMappings();
~MemoryMappingLayout();
// Memory protection masks.
static const uptr kProtectionRead = 1;
static const uptr kProtectionWrite = 2;
static const uptr kProtectionExecute = 4;
static const uptr kProtectionShared = 8;
private:
void LoadFromCache();
// Default implementation of GetObjectNameAndOffset.
// Quite slow, because it iterates through the whole process map for each
// lookup.
bool IterateForObjectNameAndOffset(uptr addr, uptr *offset,
char filename[], uptr filename_size,
uptr *protection) {
Reset();
uptr start, end, file_offset;
for (int i = 0; Next(&start, &end, &file_offset, filename, filename_size,
protection);
i++) {
if (addr >= start && addr < end) {
// Don't subtract 'start' for the first entry:
// * If a binary is compiled w/o -pie, then the first entry in
// process maps is likely the binary itself (all dynamic libs
// are mapped higher in address space). For such a binary,
// instruction offset in binary coincides with the actual
// instruction address in virtual memory (as code section
// is mapped to a fixed memory range).
// * If a binary is compiled with -pie, all the modules are
// mapped high at address space (in particular, higher than
// shadow memory of the tool), so the module can't be the
// first entry.
*offset = (addr - (i ? start : 0)) + file_offset;
return true;
}
}
if (filename_size)
filename[0] = '\0';
return false;
}
# if defined __linux__
ProcSelfMapsBuff proc_self_maps_;
char *current_;
// Static mappings cache.
static ProcSelfMapsBuff cached_proc_self_maps_;
static StaticSpinMutex cache_lock_; // protects cached_proc_self_maps_.
# elif defined __APPLE__
template<u32 kLCSegment, typename SegmentCommand>
bool NextSegmentLoad(uptr *start, uptr *end, uptr *offset,
char filename[], uptr filename_size,
uptr *protection);
int current_image_;
u32 current_magic_;
u32 current_filetype_;
int current_load_cmd_count_;
char *current_load_cmd_addr_;
# endif
};
#endif // _WIN32
} // namespace __sanitizer
#endif // SANITIZER_PROCMAPS_H