/*++
Copyright (c) 2000 Microsoft Corporation
Module Name:
heapleak.c
Abstract:
Garbage collection leak detection
Author:
Adrian Marinescu (adrmarin) 04-24-2000
Revision History:
--*/
#include "ntrtlp.h"
#include "heap.h"
#include "heappriv.h"
//
// heap walking contexts.
//
#define CONTEXT_START_GLOBALS 11
#define CONTEXT_START_HEAP 1
#define CONTEXT_END_HEAP 2
#define CONTEXT_START_SEGMENT 3
#define CONTEXT_END_SEGMENT 4
#define CONTEXT_FREE_BLOCK 5
#define CONTEXT_BUSY_BLOCK 6
#define CONTEXT_LOOKASIDE_BLOCK 7
#define CONTEXT_VIRTUAL_BLOCK 8
#define CONTEXT_END_BLOCKS 9
#define CONTEXT_ERROR 10
typedef BOOLEAN (*HEAP_ITERATOR_CALLBACK)(
IN ULONG Context,
IN PHEAP HeapAddress,
IN PHEAP_SEGMENT SegmentAddress,
IN PHEAP_ENTRY EntryAddress,
IN ULONG_PTR Data
);
//
// Garbage collector structures
//
typedef enum _USAGE_TYPE {
UsageUnknown,
UsageModule,
UsageHeap,
UsageOther
} USAGE_TYPE;
typedef struct _HEAP_BLOCK {
LIST_ENTRY Entry;
ULONG_PTR BlockAddress;
ULONG_PTR Size;
LONG Count;
} HEAP_BLOCK, *PHEAP_BLOCK;
typedef struct _BLOCK_DESCR {
USAGE_TYPE Type;
ULONG_PTR Heap;
LONG Count;
HEAP_BLOCK Blocks[1];
}BLOCK_DESCR, *PBLOCK_DESCR;
typedef struct _MEMORY_MAP {
ULONG_PTR Granularity;
ULONG_PTR Offset;
ULONG_PTR MaxAddress;
CHAR FlagsBitmap[256 / 8];
union{
struct _MEMORY_MAP * Details[ 256 ];
PBLOCK_DESCR Usage[ 256 ];
};
struct _MEMORY_MAP * Parent;
} MEMORY_MAP, *PMEMORY_MAP;
//
// Process leak detection flags
//
#define INSPECT_LEAKS 1
#define BREAK_ON_LEAKS 2
ULONG RtlpShutdownProcessFlags = 0;
//
// Allocation routines. It creates a temporary heap for the temporary
// leak detection structures
//
HANDLE RtlpLeakHeap;
#define RtlpLeakAllocateBlock(Size) RtlAllocateHeap(RtlpLeakHeap, 0, Size)
//
// Local data declarations
//
MEMORY_MAP RtlpProcessMemoryMap;
LIST_ENTRY RtlpBusyList;
LIST_ENTRY RtlpLeakList;
ULONG RtlpLeaksCount = 0;
ULONG_PTR RtlpLDPreviousPage = 0;
ULONG_PTR RtlpLDCrtPage = 0;
LONG RtlpLDNumBlocks = 0;
PHEAP_BLOCK RtlpTempBlocks = NULL;
ULONG_PTR RtlpCrtHeapAddress = 0;
ULONG_PTR RtlpLeakHeapAddress = 0;
ULONG_PTR RtlpPreviousStartAddress = 0;
//
// Debugging facility
//
ULONG_PTR RtlpBreakAtAddress = MAXULONG_PTR;
//
// Walking heap routines. These are general purposes routines that
// receive a callback function to handle a specific operation
//
BOOLEAN
RtlpReadHeapSegment(
IN PHEAP Heap,
IN ULONG SegmentIndex,
IN PHEAP_SEGMENT Segment,
IN HEAP_ITERATOR_CALLBACK HeapCallback
)
/*++
Routine Description:
This routine is called to walk a heap segment. For each block
from the segment is invoked the HeapCallback function.
Arguments:
Heap - The heap being walked
SegmentIndex - The index of this segment
Segment - The segment to be walked
HeapCallback - a HEAP_ITERATOR_CALLBACK function passed down from the heap walk
Return Value:
TRUE if succeeds.
--*/
{
PHEAP_ENTRY PrevEntry, Entry, NextEntry;
PHEAP_UNCOMMMTTED_RANGE UnCommittedRange;
ULONG_PTR UnCommittedRangeAddress = 0;
SIZE_T UnCommittedRangeSize = 0;
//
// Ask the callback if we're required to walk this segment. Return otherwise.
//
if (!(*HeapCallback)( CONTEXT_START_SEGMENT,
Heap,
Segment,
0,
0
)) {
return FALSE;
}
//
// Prepare to read the uncommitted ranges. we need to jump
// to the next uncommitted range for each last block
//
UnCommittedRange = Segment->UnCommittedRanges;
if (UnCommittedRange) {
UnCommittedRangeAddress = (ULONG_PTR)UnCommittedRange->Address;
UnCommittedRangeSize = UnCommittedRange->Size;
}
//
// Walk the segment, block by block
//
Entry = (PHEAP_ENTRY)Segment->BaseAddress;
PrevEntry = 0;
while (Entry < Segment->LastValidEntry) {
ULONG EntryFlags = Entry->Flags;
//
// Determine the next block entry. Size is in heap granularity and
// sizeof(HEAP_ENTRY) == HEAP_GRANULARITY.
//
NextEntry = Entry + Entry->Size;
(*HeapCallback)( (Entry->Flags & HEAP_ENTRY_BUSY ?
CONTEXT_BUSY_BLOCK :
CONTEXT_FREE_BLOCK),
Heap,
Segment,
Entry,
Entry->Size
);
PrevEntry = Entry;
Entry = NextEntry;
//
// Check whether this is the last entry
//
if (EntryFlags & HEAP_ENTRY_LAST_ENTRY) {
if ((ULONG_PTR)Entry == UnCommittedRangeAddress) {
//
// Here we need to skip the uncommited range and jump
// to the next valid block
//
PrevEntry = 0;
Entry = (PHEAP_ENTRY)(UnCommittedRangeAddress + UnCommittedRangeSize);
UnCommittedRange = UnCommittedRange->Next;
if (UnCommittedRange) {
UnCommittedRangeAddress = UnCommittedRange->Address;
UnCommittedRangeSize = UnCommittedRange->Size;
}
} else {
//
// We finished the search because we exausted the uncommitted
// ranges
//
break;
}
}
}
//
// Return to our caller.
//
return TRUE;
}
BOOLEAN
RtlpReadHeapData(
IN PHEAP Heap,
IN HEAP_ITERATOR_CALLBACK HeapCallback
)
/*++
Routine Description:
This routine is called to walk a heap. This means:
- walking all segments
- walking the virtual blocks
- walking the lookaside
Arguments:
Heap - The heap being walked
HeapCallback - a HEAP_ITERATOR_CALLBACK function passed down from the heap walk
Return Value:
TRUE if succeeds.
--*/
{
ULONG SegmentCount;
PLIST_ENTRY Head, Next;
PHEAP_LOOKASIDE Lookaside = (PHEAP_LOOKASIDE)RtlpGetLookasideHeap(Heap);
//
// Flush the lookaside first
//
if (Lookaside != NULL) {
ULONG i;
PVOID Block;
Heap->FrontEndHeap = NULL;
Heap->FrontEndHeapType = 0;
for (i = 0; i < HEAP_MAXIMUM_FREELISTS; i += 1) {
while ((Block = RtlpAllocateFromHeapLookaside(&(Lookaside[i]))) != NULL) {
RtlFreeHeap( Heap, 0, Block );
}
}
}
//
// Check whether we're required to walk this heap
//
if (!(*HeapCallback)( CONTEXT_START_HEAP,
Heap,
0,
0,
0
)) {
return FALSE;
}
//
// Start walking through the segments
//
for (SegmentCount = 0; SegmentCount < HEAP_MAXIMUM_SEGMENTS; SegmentCount++) {
PHEAP_SEGMENT Segment = Heap->Segments[SegmentCount];
if (Segment) {
//
// Call the appropriate routine to walk a valid segment
//
RtlpReadHeapSegment( Heap,
SegmentCount,
Segment,
HeapCallback
);
}
}
//
// Start walking the virtual block list
//
Head = &Heap->VirtualAllocdBlocks;
Next = Head->Flink;
while (Next != Head) {
PHEAP_VIRTUAL_ALLOC_ENTRY VirtualAllocBlock;
VirtualAllocBlock = CONTAINING_RECORD(Next, HEAP_VIRTUAL_ALLOC_ENTRY, Entry);
(*HeapCallback)( CONTEXT_VIRTUAL_BLOCK,
Heap,
0,
NULL,
(ULONG_PTR)VirtualAllocBlock
);
Next = Next->Flink;
}
if (!(*HeapCallback)( CONTEXT_END_BLOCKS,
Heap,
0,
0,
0
)) {
return FALSE;
}
return TRUE;
}
VOID
RtlpReadProcessHeaps(
IN HEAP_ITERATOR_CALLBACK HeapCallback
)
/*++
Routine Description:
This routine is called to walk the existing heaps in the current process
Arguments:
HeapCallback - a HEAP_ITERATOR_CALLBACK function passed down from the heap walk
Return Value:
TRUE if succeeds.
--*/
{
ULONG i;
PPEB ProcessPeb = NtCurrentPeb();
if (!(*HeapCallback)( CONTEXT_START_GLOBALS,
0,
0,
0,
(ULONG_PTR)ProcessPeb
)) {
return;
}
//
// Walk the heaps from the process PEB
//
for (i = 0; i < ProcessPeb->NumberOfHeaps; i++) {
RtlpReadHeapData ( (PHEAP)(ProcessPeb->ProcessHeaps[ i ]),
HeapCallback
);
}
}
VOID
RtlpInitializeMap (
IN PMEMORY_MAP MemMap,
IN PMEMORY_MAP Parent
)
/*++
Routine Description:
This routine initialize a memory map structure
Arguments:
MemMap - Map being initializated
Parent - The upper level map
Return Value:
None
--*/
{
//
// Clear the memory map data
//
RtlZeroMemory(MemMap, sizeof(*MemMap));
//
// Save the upper level map
//
MemMap->Parent = Parent;
//
// Determine the granularity from the parent's granularity
//
if (Parent) {
MemMap->Granularity = Parent->Granularity / 256;
}
}
VOID
RtlpSetBlockInfo (
IN PMEMORY_MAP MemMap,
IN ULONG_PTR Base,
IN ULONG_PTR Size,
IN PBLOCK_DESCR BlockDescr
)
/*++
Routine Description:
The routine will set a given block descriptor for a range
in the memory map.
Arguments:
MemMap - The memory map
Base - base address for the range to be set.
Size - size in bytes of the zone
BlockDescr - The pointer to the BLOCK_DESCR structure to be set
Return Value:
None
--*/
{
ULONG_PTR Start, End;
ULONG_PTR i;
//
// Check wheter we got a valid range
//
if (((Base + Size - 1) < MemMap->Offset) ||
(Base > MemMap->MaxAddress)
) {
return;
}
//
// Determine the starting index to be set
//
if (Base > MemMap->Offset) {
Start = (Base - MemMap->Offset) / MemMap->Granularity;
} else {
Start = 0;
}
//
// Determine the ending index to be set
//
End = (Base - MemMap->Offset + Size - 1) / MemMap->Granularity;
if (End > 255) {
End = 255;
}
for (i = Start; i <= End; i++) {
//
// Check whether this is the lowes memory map level
//
if (MemMap->Granularity == PAGE_SIZE) {
//
// This is the last level in the memory map, so we can apply
// the block descriptor here
//
if (BlockDescr) {
//
// Check if we already have a block descriptor here
//
if (MemMap->Usage[i] != NULL) {
if (MemMap->Usage[i] != BlockDescr) {
DbgPrint("Error\n");
}
}
//
// Assign the given descriptor
//
MemMap->Usage[i] = BlockDescr;
} else {
//
// We didn't recedive a block descriptor. We set
// then the given flag
//
MemMap->FlagsBitmap[i / 8] |= 1 << (i % 8);
}
} else {
//
// This isn't the lowest map level. We recursively call
// this function for the next detail range
//
if (!MemMap->Details[i]) {
//
// Allocate a new map
//
MemMap->Details[i] = RtlpLeakAllocateBlock( sizeof(*MemMap) );
if (!MemMap->Details[i]) {
DbgPrint("Error allocate\n");
}
//
// Initialize the map and link it with the current one
//
RtlpInitializeMap(MemMap->Details[i], MemMap);
MemMap->Details[i]->Offset = MemMap->Offset + MemMap->Granularity * i;
MemMap->Details[i]->MaxAddress = MemMap->Offset + MemMap->Granularity * (i+1) - 1;
}
RtlpSetBlockInfo(MemMap->Details[i], Base, Size, BlockDescr);
}
}
}
PBLOCK_DESCR
RtlpGetBlockInfo (
IN PMEMORY_MAP MemMap,
IN ULONG_PTR Base
)
/*++
Routine Description:
This function will return the appropriate Block descriptor
for a given base address
Arguments:
MemMap - The memory map
Base - The base address for the descriptor we are looking for
Return Value:
None
--*/
{
ULONG_PTR Start;
PBLOCK_DESCR BlockDescr = NULL;
//
// Validate the range
//
if ((Base < MemMap->Offset) ||
(Base > MemMap->MaxAddress)
) {
return NULL;
}
//
// Determine the appropriate index for lookup
//
if (Base > MemMap->Offset) {
Start = (Base - MemMap->Offset) / MemMap->Granularity;
} else {
Start = 0;
}
//
// If this is the lowest map level we'll return that entry
//
if (MemMap->Granularity == PAGE_SIZE) {
return MemMap->Usage[ Start ];
} else {
//
// We need a lower detail level call
//
if (MemMap->Details[ Start ]) {
return RtlpGetBlockInfo( MemMap->Details[Start], Base );
}
}
//
// We didn't find something for this address, we'll return NULL then
//
return NULL;
}
BOOLEAN
RtlpGetMemoryFlag (
IN PMEMORY_MAP MemMap,
IN ULONG_PTR Base
)
/*++
Routine Description:
This function returns the flag for a given base address
Arguments:
MemMap - The memory map
Base - The base address we want to know the flag
Return Value:
None
--*/
{
ULONG_PTR Start;
PBLOCK_DESCR BlockDescr = NULL;
//
// Validate the base address
//
if ((Base < MemMap->Offset) ||
(Base > MemMap->MaxAddress)
) {
return FALSE;
}
//
// Determine the appropriate index for the given base address
//
if (Base > MemMap->Offset) {
Start = (Base - MemMap->Offset) / MemMap->Granularity;
} else {
Start = 0;
}
if (MemMap->Granularity == PAGE_SIZE) {
//
// Return the bit value if are in the case of
// the lowest detail level
//
return (MemMap->FlagsBitmap[Start / 8] & (1 << (Start % 8))) != 0;
} else {
//
// Lookup in the detailed map
//
if (MemMap->Details[Start]) {
return RtlpGetMemoryFlag(MemMap->Details[Start], Base);
}
}
return FALSE;
}
VOID
RtlpInitializeLeakDetection ()
/*++
Routine Description:
This function initialize the leak detection structures
Arguments:
Return Value:
None
--*/
{
ULONG_PTR AddressRange = PAGE_SIZE;
ULONG_PTR PreviousAddressRange = PAGE_SIZE;
//
// Initialize the global memory map
//
RtlpInitializeMap(&RtlpProcessMemoryMap, NULL);
//
// Initialize the lists
//
InitializeListHead( &RtlpBusyList );
InitializeListHead( &RtlpLeakList );
//
// Determine the granularity for the highest memory map level
//
while (TRUE) {
AddressRange = AddressRange * 256;
if (AddressRange < PreviousAddressRange) {
RtlpProcessMemoryMap.MaxAddress = MAXULONG_PTR;
RtlpProcessMemoryMap.Granularity = PreviousAddressRange;
break;
}
PreviousAddressRange = AddressRange;
}
RtlpTempBlocks = RtlpLeakAllocateBlock(PAGE_SIZE);
}
BOOLEAN
RtlpPushPageDescriptor(
IN ULONG_PTR Page,
IN ULONG_PTR NumPages
)
/*++
Routine Description:
This routine binds the temporary block data into a block descriptor
structure and push it to the memory map
Arguments:
Page - The start page that wil contain this data
NumPages - The number of pages to be set
Return Value:
TRUE if succeeds.
--*/
{
PBLOCK_DESCR PBlockDescr;
PBLOCK_DESCR PreviousDescr;
//
// Check whether we already have a block descriptor there
//
PreviousDescr = RtlpGetBlockInfo( &RtlpProcessMemoryMap, Page * PAGE_SIZE );
if (PreviousDescr) {
DbgPrint("Conflicting descriptors %08lx\n", PreviousDescr);
return FALSE;
}
//
// We need to allocate a block descriptor structure and initializate it
// with the acquired data.
//
PBlockDescr = (PBLOCK_DESCR)RtlpLeakAllocateBlock(sizeof(BLOCK_DESCR) + (RtlpLDNumBlocks - 1) * sizeof(HEAP_BLOCK));
if (!PBlockDescr) {
DbgPrint("Unable to allocate page descriptor\n");
return FALSE;
}
PBlockDescr->Type = UsageHeap;
PBlockDescr->Count = RtlpLDNumBlocks;
PBlockDescr->Heap = RtlpCrtHeapAddress;
//
// Copy the temporary block buffer
//
RtlCopyMemory(PBlockDescr->Blocks, RtlpTempBlocks, RtlpLDNumBlocks * sizeof(HEAP_BLOCK));
//
// If this page doesn't bnelong to the temporary heap, we insert all these blocks
// in the busy list
//
if (RtlpCrtHeapAddress != RtlpLeakHeapAddress) {
LONG i;
for (i = 0; i < RtlpLDNumBlocks; i++) {
InitializeListHead( &PBlockDescr->Blocks[i].Entry );
//
// We might have a blockin more different pages. but We'll
// insert only ones in the list
//
if (PBlockDescr->Blocks[i].BlockAddress != RtlpPreviousStartAddress) {
InsertTailList(&RtlpLeakList, &PBlockDescr->Blocks[i].Entry);
PBlockDescr->Blocks[i].Count = 0;
//
// Save the last block address
//
RtlpPreviousStartAddress = PBlockDescr->Blocks[i].BlockAddress;
}
}
}
//
// Set the memory map with this block descriptor
//
RtlpSetBlockInfo(&RtlpProcessMemoryMap, Page * PAGE_SIZE, NumPages * PAGE_SIZE, PBlockDescr);
return TRUE;
}
BOOLEAN
RtlpRegisterHeapBlocks (
IN ULONG Context,
IN PHEAP Heap OPTIONAL,
IN PHEAP_SEGMENT Segment OPTIONAL,
IN PHEAP_ENTRY Entry OPTIONAL,
IN ULONG_PTR Data OPTIONAL
)
/*++
Routine Description:
This is the callback routine invoked while parsing the
process heaps. Depending on the context it is invoked
it performs different tasks.
Arguments:
Context - The context this callback is being invoked
Heap - The Heap structure
Segment - The current Segment (if any)
Entry - The current block entry (if any)
Data - Additional data
Return Value:
TRUE if succeeds.
--*/
{
//
// Check whether we need to break at this address
//
if ((ULONG_PTR)Entry == RtlpBreakAtAddress) {
DbgBreakPoint();
}
if (Context == CONTEXT_START_HEAP) {
//
// The only thing we need to do in this case
// is to set the global current heap address
//
RtlpCrtHeapAddress = (ULONG_PTR)Heap;
return TRUE;
}
//
// For a new segment, we mark the flag for the whole
// reserved space for the segment the flag to TRUE
//
if (Context == CONTEXT_START_SEGMENT) {
RtlpSetBlockInfo(&RtlpProcessMemoryMap, (ULONG_PTR)Segment->BaseAddress, Segment->NumberOfPages * PAGE_SIZE, NULL);
return TRUE;
}
if (Context == CONTEXT_ERROR) {
DbgPrint("HEAP %p (Seg %p) At %p Error: %s\n",
Heap,
Segment,
Entry,
Data
);
return TRUE;
}
if (Context == CONTEXT_END_BLOCKS) {
if (RtlpLDPreviousPage) {
RtlpPushPageDescriptor(RtlpLDPreviousPage, 1);
}
RtlpLDPreviousPage = 0;
RtlpLDNumBlocks = 0;
} else if (Context == CONTEXT_BUSY_BLOCK) {
ULONG_PTR EndPage;
//
// EnrtySize is assuming is the same as heap granularity
//
EndPage = (((ULONG_PTR)(Entry + Entry->Size)) - 1)/ PAGE_SIZE;
//
// Check whether we received a valid block
//
if ((Context == CONTEXT_BUSY_BLOCK) &&
!RtlpGetMemoryFlag(&RtlpProcessMemoryMap, (ULONG_PTR)Entry)) {
DbgPrint("%p address isn't from the heap\n", Entry);
}
//
// Determine the starting page that contains the block
//
RtlpLDCrtPage = ((ULONG_PTR)Entry) / PAGE_SIZE;
if (RtlpLDCrtPage != RtlpLDPreviousPage) {
//
// We moved to an other page, so we need to save the previous
// information before going further
//
if (RtlpLDPreviousPage) {
RtlpPushPageDescriptor(RtlpLDPreviousPage, 1);
}
//
// Reset the temporary data. We're starting a new page now
//
RtlpLDPreviousPage = RtlpLDCrtPage;
RtlpLDNumBlocks = 0;
}
//
// Add this block to the current list
//
RtlpTempBlocks[RtlpLDNumBlocks].BlockAddress = (ULONG_PTR)Entry;
RtlpTempBlocks[RtlpLDNumBlocks].Count = 0;
RtlpTempBlocks[RtlpLDNumBlocks].Size = Entry->Size * sizeof(HEAP_ENTRY);
RtlpLDNumBlocks++;
if (EndPage != RtlpLDCrtPage) {
//
// The block ends on a different page. We can then save the
// starting page and all others but the last one
//
RtlpPushPageDescriptor(RtlpLDCrtPage, 1);
RtlpLDNumBlocks = 0;
RtlpTempBlocks[RtlpLDNumBlocks].BlockAddress = (ULONG_PTR)Entry;
RtlpTempBlocks[RtlpLDNumBlocks].Count = 0;
RtlpTempBlocks[RtlpLDNumBlocks].Size = Entry->Size * sizeof(HEAP_ENTRY);
RtlpLDNumBlocks += 1;
if (EndPage - RtlpLDCrtPage > 1) {
RtlpPushPageDescriptor(RtlpLDCrtPage + 1, EndPage - RtlpLDCrtPage - 1);
}
RtlpLDPreviousPage = EndPage;
}
} else if (Context == CONTEXT_VIRTUAL_BLOCK) {
PHEAP_VIRTUAL_ALLOC_ENTRY VirtualAllocBlock = (PHEAP_VIRTUAL_ALLOC_ENTRY)Data;
ULONG_PTR EndPage;
//
// EnrtySize is assuming is the same as heap granularity
//
EndPage = ((ULONG_PTR)Data + VirtualAllocBlock->CommitSize - 1)/ PAGE_SIZE;
RtlpLDCrtPage = (Data) / PAGE_SIZE;
if (RtlpLDCrtPage != RtlpLDPreviousPage) {
//
// Save the previous data if we're moving to a new page
//
if (RtlpLDPreviousPage) {
RtlpPushPageDescriptor(RtlpLDPreviousPage, 1);
}
RtlpLDPreviousPage = RtlpLDCrtPage;
RtlpLDNumBlocks = 0;
}
//
// Initialize the block descriptor structure as we are
// starting a new page
//
RtlpLDNumBlocks = 0;
RtlpTempBlocks[RtlpLDNumBlocks].BlockAddress = (ULONG_PTR)Entry;
RtlpTempBlocks[RtlpLDNumBlocks].Count = 0;
RtlpTempBlocks[RtlpLDNumBlocks].Size = VirtualAllocBlock->CommitSize;
RtlpLDNumBlocks += 1;
RtlpPushPageDescriptor(RtlpLDCrtPage, EndPage - RtlpLDCrtPage + 1);
RtlpLDPreviousPage = 0;
} else if ( Context == CONTEXT_LOOKASIDE_BLOCK ) {
PBLOCK_DESCR PBlockDescr;
LONG i;
//
// Check whether we received a valid block
//
if (!RtlpGetMemoryFlag(&RtlpProcessMemoryMap, (ULONG_PTR)Entry)) {
DbgPrint("%p address isn't from the heap\n", Entry);
}
PBlockDescr = RtlpGetBlockInfo( &RtlpProcessMemoryMap, (ULONG_PTR)Entry );
if (!PBlockDescr) {
DbgPrint("Error finding block from lookaside %p\n", Entry);
return FALSE;
}
//
// Find the block in the block descriptor
//
for (i = 0; i < PBlockDescr->Count; i++) {
if ((PBlockDescr->Blocks[i].BlockAddress <= (ULONG_PTR)Entry) &&
(PBlockDescr->Blocks[i].BlockAddress + PBlockDescr->Blocks[i].Size > (ULONG_PTR)Entry)) {
PBlockDescr->Blocks[i].Count = -10000;
//
// Remove the block from the busy list
//
RemoveEntryList(&PBlockDescr->Blocks[i].Entry);
return TRUE;
}
}
//
// A block from lookaside should be busy for the heap structures.
// If we didn't find the block in the block list, something went
// wrong. We make some noise here.
//
DbgPrint("Error, block %p from lookaside not found in allocated block list\n", Entry);
}
return TRUE;
}
PHEAP_BLOCK
RtlpGetHeapBlock (
IN ULONG_PTR Address
)
/*++
Routine Description:
The function performs a lookup for the block descriptor
for a given address. The address can point somewhere inside the
block.
Arguments:
Address - The lookup address.
Return Value:
Returns a pointer to the heap descriptor structure if found.
This is not NULL if the given address belongs to any busy heap block.
--*/
{
PBLOCK_DESCR PBlockDescr;
LONG i;
//
// Find the block descriptor for the given address
//
PBlockDescr = RtlpGetBlockInfo( &RtlpProcessMemoryMap, Address );
if ( (PBlockDescr != NULL)
&&
(PBlockDescr->Heap != RtlpLeakHeapAddress)) {
//
// Search through the blocks
//
for (i = 0; i < PBlockDescr->Count; i++) {
if ((PBlockDescr->Blocks[i].BlockAddress <= Address) &&
(PBlockDescr->Blocks[i].BlockAddress + PBlockDescr->Blocks[i].Size > Address)) {
//
// Search again if the caller didn't pass a start address
//
if (PBlockDescr->Blocks[i].BlockAddress != Address) {
return RtlpGetHeapBlock(PBlockDescr->Blocks[i].BlockAddress);
}
//
// we found a block here.
//
return &(PBlockDescr->Blocks[i]);
}
}
}
return NULL;
}
VOID
RtlpDumpEntryHeader ( )
/*++
Routine Description:
Writes the table header
Arguments:
Return Value:
--*/
{
DbgPrint("Entry User Heap Size PrevSize Flags\n");
DbgPrint("------------------------------------------------------------\n");
}
VOID
RtlpDumpEntryFlagDescription(
IN ULONG Flags
)
/*++
Routine Description:
The function writes a description string for the given block flag
Arguments:
Flags - Block flags
Return Value:
--*/
{
if (Flags & HEAP_ENTRY_BUSY) DbgPrint("busy "); else DbgPrint("free ");
if (Flags & HEAP_ENTRY_EXTRA_PRESENT) DbgPrint("extra ");
if (Flags & HEAP_ENTRY_FILL_PATTERN) DbgPrint("fill ");
if (Flags & HEAP_ENTRY_VIRTUAL_ALLOC) DbgPrint("virtual ");
if (Flags & HEAP_ENTRY_LAST_ENTRY) DbgPrint("last ");
if (Flags & HEAP_ENTRY_SETTABLE_FLAGS) DbgPrint("user_flag ");
}
VOID
RtlpDumpEntryInfo(
IN ULONG_PTR HeapAddress,
IN PHEAP_ENTRY Entry
)
/*++
Routine Description:
The function logs a heap block information
Arguments:
HeapAddress - The heap that contains the entry to be displayied
Entry - The block entry
Return Value:
None.
--*/
{
DbgPrint("%p %p %p %8lx %8lx ",
Entry,
(Entry + 1),
HeapAddress,
Entry->Size << HEAP_GRANULARITY_SHIFT,
Entry->PreviousSize << HEAP_GRANULARITY_SHIFT
);
RtlpDumpEntryFlagDescription(Entry->Flags);
DbgPrint("\n");
}
BOOLEAN
RtlpScanHeapAllocBlocks ( )
/*++
Routine Description:
The function does:
- Scan all busy blocks and update the references to all other blocks
- Build the list with leaked blocks
- Reports the leaks
Arguments:
Return Value:
Return TRUE if succeeds.
--*/
{
PLIST_ENTRY Next;
//
// walk the busy list
//
Next = RtlpBusyList.Flink;
while (Next != &RtlpBusyList) {
PHEAP_BLOCK Block = CONTAINING_RECORD(Next, HEAP_BLOCK, Entry);
PULONG_PTR CrtAddress = (PULONG_PTR)(Block->BlockAddress + sizeof(HEAP_ENTRY));
//
// Move to the next block in the list
//
Next = Next->Flink;
//
// Iterate through block space and update
// the references for every block found here
//
while ((ULONG_PTR)CrtAddress < Block->BlockAddress + Block->Size) {
PHEAP_BLOCK pBlock = RtlpGetHeapBlock( *CrtAddress );
if (pBlock) {
//
// We found a block. we increment then the reference count
//
if (pBlock->Count == 0) {
RemoveEntryList(&pBlock->Entry);
InsertTailList(&RtlpBusyList, &pBlock->Entry);
}
pBlock->Count += 1;
if (pBlock->BlockAddress == RtlpBreakAtAddress) {
DbgBreakPoint();
}
}
//
// Go to the next possible pointer
//
CrtAddress++;
}
}
//
// Now walk the leak list, and report leaks.
// Also any pointer found here will be dereferenced and added to
// the end of list.
//
Next = RtlpLeakList.Flink;
while (Next != &RtlpLeakList) {
PHEAP_BLOCK Block = CONTAINING_RECORD(Next, HEAP_BLOCK, Entry);
PBLOCK_DESCR PBlockDescr = RtlpGetBlockInfo( &RtlpProcessMemoryMap, Block->BlockAddress );
PULONG_PTR CrtAddress = (PULONG_PTR)(Block->BlockAddress + sizeof(HEAP_ENTRY));
if (PBlockDescr) {
//
// First time we need to display the header
//
if (RtlpLeaksCount == 0) {
RtlpDumpEntryHeader();
}
//
// Display the information for this block
//
RtlpDumpEntryInfo( PBlockDescr->Heap, (PHEAP_ENTRY)Block->BlockAddress);
RtlpLeaksCount += 1;
}
//
// Go to the next item from the leak list
//
Next = Next->Flink;
}
return TRUE;
}
BOOLEAN
RtlpScanProcessVirtualMemory()
/*++
Routine Description:
This function scan the whole process virtual address space and lookup
for possible references to busy blocks
Arguments:
Return Value:
Return TRUE if succeeds.
--*/
{
ULONG_PTR lpAddress = 0;
MEMORY_BASIC_INFORMATION Buffer;
NTSTATUS Status = STATUS_SUCCESS;
//
// Loop through virtual memory zones, we'll skip the heap space here
//
while ( NT_SUCCESS( Status ) ) {
Status = ZwQueryVirtualMemory( NtCurrentProcess(),
(PVOID)lpAddress,
MemoryBasicInformation,
&Buffer,
sizeof(Buffer),
NULL );
if (NT_SUCCESS( Status )) {
//
// If the page can be written, it might contain pointers to heap blocks
// We'll exclude at this point the heap address space. We scan the heaps
// later.
//
if ((Buffer.AllocationProtect & (PAGE_READWRITE | PAGE_EXECUTE_READWRITE | PAGE_WRITECOPY | PAGE_EXECUTE_WRITECOPY))
&&
(Buffer.State & MEM_COMMIT)
&&
!RtlpGetMemoryFlag(&RtlpProcessMemoryMap, (ULONG_PTR)lpAddress)) {
PULONG_PTR Pointers = (PULONG_PTR)lpAddress;
ULONG_PTR i, Count;
//
// compute the number of possible pointers
//
Count = Buffer.RegionSize / sizeof(ULONG_PTR);
try {
//
// Loop through pages and check any possible pointer reference
//
for (i = 0; i < Count; i++) {
//
// Check whether we have a pointer to a busy heap block
//
PHEAP_BLOCK pBlock = RtlpGetHeapBlock(*Pointers);
if (pBlock) {
if (pBlock->BlockAddress == RtlpBreakAtAddress) {
DbgBreakPoint();
}
if (pBlock->Count == 0) {
RemoveEntryList(&pBlock->Entry);
InsertTailList(&RtlpBusyList, &pBlock->Entry);
}
pBlock->Count += 1;
}
//
// Move to the next pointer
//
Pointers++;
}
} except( EXCEPTION_EXECUTE_HANDLER ) {
//
// Nothing more to do
//
}
}
//
// Move to the next VM range to query
//
lpAddress += Buffer.RegionSize;
}
}
//
// Now update the references provided by the busy blocks
//
RtlpScanHeapAllocBlocks( );
return TRUE;
}
VOID
RtlDetectHeapLeaks ()
/*++
Routine Description:
This routine detects and display the leaks found in the current process
NOTE: The caller must make sure no other thread can change some heap data
while a tread is executing this one. In general this function is supposed
to be called from LdrShutdownProcess.
Arguments:
Return Value:
--*/
{
//
// Check if the global flag has the leak detection enabled
//
if (RtlpShutdownProcessFlags & (INSPECT_LEAKS | BREAK_ON_LEAKS)) {
RtlpLeaksCount = 0;
//
// Create a temporary heap that will be used for any alocation
// of these functions.
//
RtlpLeakHeap = RtlCreateHeap(HEAP_NO_SERIALIZE | HEAP_GROWABLE, NULL, 0, 0, NULL, NULL);
if (RtlpLeakHeap) {
PPEB ProcessPeb = NtCurrentPeb();
HeapDebugPrint( ("Inspecting leaks at process shutdown ...\n") );
RtlpInitializeLeakDetection();
//
// The last heap from the heap list is our temporary heap
//
RtlpLeakHeapAddress = (ULONG_PTR)ProcessPeb->ProcessHeaps[ ProcessPeb->NumberOfHeaps - 1 ];
//
// Scan all process heaps, build the memory map and
// the busy block list
//
RtlpReadProcessHeaps( RtlpRegisterHeapBlocks );
//
// Scan the process virtual memory and the busy blocks
// At the end build the list with leaked blocks and report them
//
RtlpScanProcessVirtualMemory();
//
// Destroy the temporary heap
//
RtlDestroyHeap(RtlpLeakHeap);
RtlpLeakHeap = NULL;
//
// Report the final statement about the process leaks
//
if (RtlpLeaksCount) {
HeapDebugPrint(("%ld leaks detected.\n", RtlpLeaksCount));
if (RtlpShutdownProcessFlags & BREAK_ON_LEAKS) {
DbgBreakPoint();
}
} else {
HeapDebugPrint( ("No leaks detected.\n"));
}
}
}
}