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[NTOS]: Add an extra layer of protection for freed nonpaged pool: write a 4-byte signature on freed blocks, and assert its valid on checked builds. Use a slightly less egocentric ASCII value than on Windows (name of the developer who wrote the first memory manager).

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svn path=/trunk/; revision=48651
This commit is contained in:
Sir Richard 2010-08-29 19:32:25 +00:00
parent b85ab20f13
commit c574f50663
1 changed files with 6 additions and 0 deletions
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6
reactos/ntoskrnl/mm/ARM3/pool.c
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@ -298,6 +298,7 @@ MiInitializeNonPagedPool(VOID)
FreeEntry = MmNonPagedPoolStart; FreeEntry = MmNonPagedPoolStart;
FirstEntry = FreeEntry; FirstEntry = FreeEntry;
FreeEntry->Size = PoolPages; FreeEntry->Size = PoolPages;
FreeEntry->Signature = MM_FREE_POOL_SIGNATURE;
FreeEntry->Owner = FirstEntry; FreeEntry->Owner = FirstEntry;
// //
@ -316,6 +317,7 @@ MiInitializeNonPagedPool(VOID)
// //
FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)FreeEntry + PAGE_SIZE); FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)FreeEntry + PAGE_SIZE);
FreeEntry->Owner = FirstEntry; FreeEntry->Owner = FirstEntry;
FreeEntry->Signature = MM_FREE_POOL_SIGNATURE;
} }
// //
@ -626,6 +628,7 @@ MiAllocatePoolPages(IN POOL_TYPE PoolType,
// Grab the entry and see if it can handle our allocation // Grab the entry and see if it can handle our allocation
// //
FreeEntry = CONTAINING_RECORD(NextEntry, MMFREE_POOL_ENTRY, List); FreeEntry = CONTAINING_RECORD(NextEntry, MMFREE_POOL_ENTRY, List);
ASSERT(FreeEntry->Signature == MM_FREE_POOL_SIGNATURE);
if (FreeEntry->Size >= SizeInPages) if (FreeEntry->Size >= SizeInPages)
{ {
// //
@ -964,6 +967,7 @@ MiFreePoolPages(IN PVOID StartingVa)
// //
FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)StartingVa + FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)StartingVa +
(NumberOfPages << PAGE_SHIFT)); (NumberOfPages << PAGE_SHIFT));
ASSERT(FreeEntry->Signature == MM_FREE_POOL_SIGNATURE);
ASSERT(FreeEntry->Owner == FreeEntry); ASSERT(FreeEntry->Owner == FreeEntry);
/* Consume this entry's pages */ /* Consume this entry's pages */
@ -1032,6 +1036,7 @@ MiFreePoolPages(IN PVOID StartingVa)
// Get the free entry descriptor for that given page range // Get the free entry descriptor for that given page range
// //
FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)StartingVa - PAGE_SIZE); FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)StartingVa - PAGE_SIZE);
ASSERT(FreeEntry->Signature == MM_FREE_POOL_SIGNATURE);
FreeEntry = FreeEntry->Owner; FreeEntry = FreeEntry->Owner;
/* Check if protected pool is enabled */ /* Check if protected pool is enabled */
@ -1118,6 +1123,7 @@ MiFreePoolPages(IN PVOID StartingVa)
// Link back to the parent free entry, and keep going // Link back to the parent free entry, and keep going
// //
NextEntry->Owner = FreeEntry; NextEntry->Owner = FreeEntry;
NextEntry->Signature = MM_FREE_POOL_SIGNATURE;
NextEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)NextEntry + PAGE_SIZE); NextEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)NextEntry + PAGE_SIZE);
} while (NextEntry != LastEntry); } while (NextEntry != LastEntry);