The data has to be written into ObjectTypeInfo based on the return length,
not only what is provided by the input buffer length. Fix suggested by
Hermès.
On a x86 system aligning the return length pointer to a 4-byte boundary
works best since pointers in general are 4-byte aligned for x86 systems.
However, what happens on a AMD64 system is that we still align this pointer
to 4-byte, ObjectTypeInfo is a 8-byte pointer and we might write into
the return length past the 4-byte boundary.
If one were to allocate a pool of memory with that length and query all
the object types info and free the said pool of memory thereafter, the
system will crash with BAD_POOL_HEADER because ObQueryTypeInfo overwrote
the return length past the 4-byte boundary length therefore leading up with
corrupted memory blocks in the pool header.
This symptom of BAD_POOL_HEADER happens exactly the same in Windows Server
2003 x64 Edition. Newer versions of Windows like 10 aren't affected.
But, Windows has another bug where they are using MaximumLength for the
calculation of the needed length to be returned to caller. MaximumLength
does not guarantee you that it includes the NULL-terminator in the length
and that potentially leads to a buffer overrun.
Also annotate the ObQueryTypeInfo function with SAL2.
https://processhacker.sourceforge.io/doc/object_8c_source.html (read the
comment in KphObjectTypeInformation).
As it currently stands the Object Manager doesn't charge any quotas when objects are created, nor it returns quotas when objects are de-allocated and freed from the objects namespace database. This alone can bring inconsistencies in the kernel as we simply don't know what is the amount charged in an object and thus we aren't keeping track of quotas flow.
Now with both PsReturnSharedPoolQuota and PsChargeSharedPoolQuota implemented, the Object Manager can now track the said flow of quotas every time an object is created or de-allocated, thus enforcing consistency with the use of quota resources.
- NtQuerySymbolicLinkObject(): Use an intermediate variable for the object header.
- Simplify code in ObpLookupEntryDirectory() by calling ObpReleaseLookupContextObject() instead.
- Use TAG_OBJECT_TYPE instead of hardcoded tag values.
- Disentangle the usage of ObpAcquireDirectoryLockExclusive() when it's
used only for accessing a directory structure, or as part of a lookup
operation.
The Obp*DirectoryLock*() -- both shared and exclusive -- functions
are only for locking an OB directory, for reading or writing its
structure members.
When performing lookup operations (insertions/deletions of entries
within a directory), use a ObpAcquireLookupContextLock() function that
exclusively locks the directory and saves extra lock state, that can
be used by ObpReleaseLookupContextObject() for cleanup.
- Add documentation for these functions.
- Rename ObDirectoryType to ObpDirectoryObjectType and remove it from NDK (this is not exported!)
- Rename ObSymbolicLinkType to ObpSymbolicLinkObjectType
- Remove duplicated ObpTypeObjectType from ob.h
