//===-- msan_allocator.cc --------------------------- ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of MemorySanitizer.
//
// MemorySanitizer allocator.
//===----------------------------------------------------------------------===//
#include "sanitizer_common/sanitizer_allocator.h"
#include "sanitizer_common/sanitizer_allocator_interface.h"
#include "msan.h"
#include "msan_allocator.h"
#include "msan_origin.h"
#include "msan_thread.h"
#include "msan_poisoning.h"
namespace __msan {
struct Metadata {
uptr requested_size;
};
struct MsanMapUnmapCallback {
void OnMap(uptr p, uptr size) const {}
void OnUnmap(uptr p, uptr size) const {
__msan_unpoison((void *)p, size);
// We are about to unmap a chunk of user memory.
// Mark the corresponding shadow memory as not needed.
FlushUnneededShadowMemory(MEM_TO_SHADOW(p), size);
if (__msan_get_track_origins())
FlushUnneededShadowMemory(MEM_TO_ORIGIN(p), size);
}
};
#if defined(__mips64)
static const uptr kMaxAllowedMallocSize = 2UL << 30;
static const uptr kRegionSizeLog = 20;
static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
typedef CompactSizeClassMap SizeClassMap;
typedef SizeClassAllocator32<0, SANITIZER_MMAP_RANGE_SIZE, sizeof(Metadata),
SizeClassMap, kRegionSizeLog, ByteMap,
MsanMapUnmapCallback> PrimaryAllocator;
#elif defined(__x86_64__)
#if SANITIZER_LINUX && !defined(MSAN_LINUX_X86_64_OLD_MAPPING)
static const uptr kAllocatorSpace = 0x700000000000ULL;
#else
static const uptr kAllocatorSpace = 0x600000000000ULL;
#endif
static const uptr kAllocatorSize = 0x80000000000; // 8T.
static const uptr kMetadataSize = sizeof(Metadata);
static const uptr kMaxAllowedMallocSize = 8UL << 30;
typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, kMetadataSize,
DefaultSizeClassMap,
MsanMapUnmapCallback> PrimaryAllocator;
#elif defined(__powerpc64__)
static const uptr kAllocatorSpace = 0x300000000000;
static const uptr kAllocatorSize = 0x020000000000; // 2T
static const uptr kMetadataSize = sizeof(Metadata);
static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, kMetadataSize,
DefaultSizeClassMap,
MsanMapUnmapCallback> PrimaryAllocator;
#elif defined(__aarch64__)
static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
static const uptr kRegionSizeLog = 20;
static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
typedef CompactSizeClassMap SizeClassMap;
typedef SizeClassAllocator32<0, SANITIZER_MMAP_RANGE_SIZE, sizeof(Metadata),
SizeClassMap, kRegionSizeLog, ByteMap,
MsanMapUnmapCallback> PrimaryAllocator;
#endif
typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
typedef LargeMmapAllocator<MsanMapUnmapCallback> SecondaryAllocator;
typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
SecondaryAllocator> Allocator;
static Allocator allocator;
static AllocatorCache fallback_allocator_cache;
static SpinMutex fallback_mutex;
void MsanAllocatorInit() {
allocator.Init(common_flags()->allocator_may_return_null);
}
AllocatorCache *GetAllocatorCache(MsanThreadLocalMallocStorage *ms) {
CHECK(ms);
CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator_cache));
return reinterpret_cast<AllocatorCache *>(ms->allocator_cache);
}
void MsanThreadLocalMallocStorage::CommitBack() {
allocator.SwallowCache(GetAllocatorCache(this));
}
static void *MsanAllocate(StackTrace *stack, uptr size, uptr alignment,
bool zeroise) {
if (size > kMaxAllowedMallocSize) {
Report("WARNING: MemorySanitizer failed to allocate %p bytes\n",
(void *)size);
return allocator.ReturnNullOrDie();
}
MsanThread *t = GetCurrentThread();
void *allocated;
if (t) {
AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
allocated = allocator.Allocate(cache, size, alignment, false);
} else {
SpinMutexLock l(&fallback_mutex);
AllocatorCache *cache = &fallback_allocator_cache;
allocated = allocator.Allocate(cache, size, alignment, false);
}
Metadata *meta =
reinterpret_cast<Metadata *>(allocator.GetMetaData(allocated));
meta->requested_size = size;
if (zeroise) {
__msan_clear_and_unpoison(allocated, size);
} else if (flags()->poison_in_malloc) {
__msan_poison(allocated, size);
if (__msan_get_track_origins()) {
stack->tag = StackTrace::TAG_ALLOC;
Origin o = Origin::CreateHeapOrigin(stack);
__msan_set_origin(allocated, size, o.raw_id());
}
}
MSAN_MALLOC_HOOK(allocated, size);
return allocated;
}
void MsanDeallocate(StackTrace *stack, void *p) {
CHECK(p);
MSAN_FREE_HOOK(p);
Metadata *meta = reinterpret_cast<Metadata *>(allocator.GetMetaData(p));
uptr size = meta->requested_size;
meta->requested_size = 0;
// This memory will not be reused by anyone else, so we are free to keep it
// poisoned.
if (flags()->poison_in_free) {
__msan_poison(p, size);
if (__msan_get_track_origins()) {
stack->tag = StackTrace::TAG_DEALLOC;
Origin o = Origin::CreateHeapOrigin(stack);
__msan_set_origin(p, size, o.raw_id());
}
}
MsanThread *t = GetCurrentThread();
if (t) {
AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
allocator.Deallocate(cache, p);
} else {
SpinMutexLock l(&fallback_mutex);
AllocatorCache *cache = &fallback_allocator_cache;
allocator.Deallocate(cache, p);
}
}
void *MsanCalloc(StackTrace *stack, uptr nmemb, uptr size) {
if (CallocShouldReturnNullDueToOverflow(size, nmemb))
return allocator.ReturnNullOrDie();
return MsanReallocate(stack, nullptr, nmemb * size, sizeof(u64), true);
}
void *MsanReallocate(StackTrace *stack, void *old_p, uptr new_size,
uptr alignment, bool zeroise) {
if (!old_p)
return MsanAllocate(stack, new_size, alignment, zeroise);
if (!new_size) {
MsanDeallocate(stack, old_p);
return nullptr;
}
Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(old_p));
uptr old_size = meta->requested_size;
uptr actually_allocated_size = allocator.GetActuallyAllocatedSize(old_p);
if (new_size <= actually_allocated_size) {
// We are not reallocating here.
meta->requested_size = new_size;
if (new_size > old_size) {
if (zeroise) {
__msan_clear_and_unpoison((char *)old_p + old_size,
new_size - old_size);
} else if (flags()->poison_in_malloc) {
stack->tag = StackTrace::TAG_ALLOC;
PoisonMemory((char *)old_p + old_size, new_size - old_size, stack);
}
}
return old_p;
}
uptr memcpy_size = Min(new_size, old_size);
void *new_p = MsanAllocate(stack, new_size, alignment, zeroise);
// Printf("realloc: old_size %zd new_size %zd\n", old_size, new_size);
if (new_p) {
CopyMemory(new_p, old_p, memcpy_size, stack);
MsanDeallocate(stack, old_p);
}
return new_p;
}
static uptr AllocationSize(const void *p) {
if (!p) return 0;
const void *beg = allocator.GetBlockBegin(p);
if (beg != p) return 0;
Metadata *b = (Metadata *)allocator.GetMetaData(p);
return b->requested_size;
}
} // namespace __msan
using namespace __msan;
uptr __sanitizer_get_current_allocated_bytes() {
uptr stats[AllocatorStatCount];
allocator.GetStats(stats);
return stats[AllocatorStatAllocated];
}
uptr __sanitizer_get_heap_size() {
uptr stats[AllocatorStatCount];
allocator.GetStats(stats);
return stats[AllocatorStatMapped];
}
uptr __sanitizer_get_free_bytes() { return 1; }
uptr __sanitizer_get_unmapped_bytes() { return 1; }
uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
int __sanitizer_get_ownership(const void *p) { return AllocationSize(p) != 0; }
uptr __sanitizer_get_allocated_size(const void *p) { return AllocationSize(p); }