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Fix some serious handle table bugs which led to memory corruption and stale values (which led to more memory corruption). Patch by Alex Ionescu.

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svn path=/trunk/; revision=32770
This commit is contained in:
KJK::Hyperion 2008-03-27 01:13:24 +00:00
parent 51a2c9f737
commit b9e079bdfb
1 changed files with 6 additions and 6 deletions
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12
reactos/ntoskrnl/ex/handle.c
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@ -17,7 +17,7 @@
LIST_ENTRY HandleTableListHead;
EX_PUSH_LOCK HandleTableListLock;
#define SizeOfHandle(x) (sizeof(HANDLE) * x)
#define SizeOfHandle(x) (sizeof(HANDLE) * (x))
/* PRIVATE FUNCTIONS *********************************************************/
@ -43,11 +43,11 @@ ExpLookupHandleTableEntry(IN PHANDLE_TABLE HandleTable,
/* Clear the tag bits and check what the next handle is */
Handle.TagBits = 0;
NextHandle = HandleTable->NextHandleNeedingPool;
NextHandle = *(volatile ULONG*)&HandleTable->NextHandleNeedingPool;
if (Handle.Value >= NextHandle) return NULL;
/* Get the table code */
TableBase = (ULONG_PTR)HandleTable->TableCode;
TableBase = *(volatile ULONG_PTR*)&HandleTable->TableCode;
/* Extract the table level and actual table base */
TableLevel = (ULONG)(TableBase & 3);
@ -734,7 +734,7 @@ ExpAllocateHandleTableEntry(IN PHANDLE_TABLE HandleTable,
ExAcquirePushLockShared(&HandleTable->HandleTableLock[i]);
/* Check if the value changed after acquiring the lock */
if (OldValue != HandleTable->FirstFree)
if (OldValue != *(volatile ULONG*)&HandleTable->FirstFree)
{
/* It did, so try again */
ExReleasePushLockShared(&HandleTable->HandleTableLock[i]);
@ -743,7 +743,7 @@ ExpAllocateHandleTableEntry(IN PHANDLE_TABLE HandleTable,
}
/* Now get the next value and do the compare */
NewValue = Entry->NextFreeTableEntry;
NewValue = *(volatile ULONG*)&Entry->NextFreeTableEntry;
NewValue1 = InterlockedCompareExchange((PLONG) &HandleTable->FirstFree,
NewValue,
OldValue);
@ -874,7 +874,7 @@ ExpLockHandleTableEntry(IN PHANDLE_TABLE HandleTable,
for (;;)
{
/* Get the current value and check if it's locked */
OldValue = (LONG_PTR)HandleTableEntry->Object;
OldValue = *(volatile LONG_PTRits *)&HandleTableEntry->Object;
if (OldValue & EXHANDLE_TABLE_ENTRY_LOCK_BIT)
{
/* It's not locked, remove the lock bit to lock it */