PsIdleProcess and PsInitialSystemProcess share the same handle table. This
leads ObGetProcessHandleCount() to report the same number of handles
when called on those system processes, when being enumerated by
NtQuerySystemInformation(SystemProcessInformation).
Instead, just return 0 for the handle count of the Idle process in SystemProcessInformation.
This is not done in ObGetProcessHandleCount(), since a separate
NtQueryInformationProcess(ProcessHandleCount) for the idle process should return
a non-zero value.
CORE-16577
Not only primary group assignation was broken but new dynamic length calculation is also broken. The length of the captured SID is not taken into account so the new dynamic length gets only the size of the default ACL present in an access token.
Therefore, the condition is always FALSE and the code never jumps to the STATUS_ALLOTTED_SPACE_EXCEEDED branch because the length will always be small than the charged dynamic length.
Addendum to 86bde3c.
With current master, what happens is that when someone wants to assign a new primary group SID for an access token, it results in an instant page fault because the primary group variable doesn't get assigned the dynamic part's address.
So the primary group variable gets an address which is basically a representation of the ACL size, hence the said address is bogus and it's where the page fault kicks in.
CORE-18249
Since we were charging the pool quota after the VAD insertion,
if the quota charge failed, the VAD would still have been inserted.
This commit attempts to resolve this issue by charging quota
before inserting the VAD thus allowing the quota charge to fail early.
Addendum to 884356a0. CORE-18028
On current master, ReactOS faces these problems:
- ObCreateObject charges both paged and non paged pool a size of TOKEN structure, not the actual dynamic contents of WHAT IS inside a token. For paged pool charge the size is that of the dynamic area (primary group + default DACL if any). This is basically what DynamicCharged is for.
For the non paged pool charge, the actual charge is that of TOKEN structure upon creation. On duplication and filtering however, the paged pool charge size is that of the inherited dynamic charged space from an existing token whereas the non paged pool size is that of the calculated token body
length for the new duplicated/filtered token. On current master, we're literally cheating the kernel by charging the wrong amount of quota not taking into account the dynamic contents which they come from UM.
- Both DynamicCharged and DynamicAvailable are not fully handled (DynamicAvailable is pretty much poorly handled with some cases still to be taking into account). DynamicCharged is barely handled, like at all.
- As a result of these two points above, NtSetInformationToken doesn't check when the caller wants to set up a new default token DACL or primary group if the newly DACL or the said group exceeds the dynamic charged boundary. So what happens is that I'm going to act like a smug bastard fat politician and whack
the primary group and DACL of an token however I want to, because why in the hell not? In reality no, the kernel has to punish whoever attempts to do that, although we currently don't.
- The dynamic area (aka DynamicPart) only picks up the default DACL but not the primary group as well. Generally the dynamic part is composed of primary group and default DACL, if provided.
In addition to that, we aren't returning the dynamic charged and available area in token statistics. SepComputeAvailableDynamicSpace helper is here to accommodate that. Apparently Windows is calculating the dynamic available area rather than just querying the DynamicAvailable field directly from the token.
My theory regarding this is like the following: on Windows both TokenDefaultDacl and TokenPrimaryGroup classes are barely used by the system components during startup (LSASS provides both a DACL and primary group when calling NtCreateToken anyway). In fact DynamicAvailable is 0 during token creation, duplication and filtering when inspecting a token with WinDBG. So
if an application wants to query token statistics that application will face a dynamic available space of 0.
On ObpChargeQuotaForObject function, the kernel will either charge the default object type charges or the specified information charges obtained from ObCreateObject API call. What happens is that if a paged pool charge is specified on ObCreateObject call the kernel will charge that
but when an object is about to be de-allocated, the amount of quota to return back to the system is the amounting of the paged pool charge specified previously by the ObCreateObject call plus the amounting of the security descriptor charge (see oblife.c / line 98).
This will result in a fatal crash with a bugcheck of QUOTA_UNDERFLOW because we are returning quota with bits of it that was never charged and that's SecurityDescriptorCharge. A QUOTA_UNDERFLOW bugcheck occurs in two following scenarios:
-- When installing Virtualbox Guest Additions and prompting the installer to reboot the system for you
-- When logging off and on back to the system and then you restart the system normally
This bug has been discovered whilst working on #4555 PR.
TokenGroupsAndPrivileges is the younger sister of two TokenGroups and TokenPrivileges classes. In its purpose there's no huge substantial differences apart that this class comes with its own structure, TOKEN_GROUPS_AND_PRIVILEGES, and that this structure comes with extra information.
In NtQueryInformationToken function, remove the useless and redundant NULL check for two primary reasons. First, DefaultQueryInfoBufferCheck already does the necessary probing validation checks and second, ReturnLength must NEVER be NULL!
If the caller does not respect the calling rules of NtQueryInformationToken, the caller is expected to be miserably punished.
NtQueryInformationToken is by far the only system call in NT where ReturnLength simply cannot be optional. On Windows this parameter is always probed and an argument to NULL directly leads to an access violation exception.
This is due to the fact of how tokens work, as its information contents (token user, owner, primary group, et al) are dynamic and can vary throughout over time in memory.
What happens on current ReactOS master however is that ReturnLength is only probed if the parameter is not NULL. On a NULL case scenario the probing checks succeed and NtQueryInformationToken fails later. For this, just get rid of CompleteProbing
parameter and opt in for a bit mask flag based approach, with ICIF_FORCE_RETURN_LENGTH_PROBE being set on DefaultQueryInfoBufferCheck which NtQueryInformationToken calls it to do sanity checks.
In addition to that...
- Document the ICIF probe helpers
- Annotate the ICIF prope helpers with SAL
- With the riddance of CompleteProbing and adoption of flags based approach, add ICIF_PROBE_READ_WRITE and ICIF_PROBE_READ flags alongside with ICIF_FORCE_RETURN_LENGTH_PROBE
The current state of Security manager's code is kind of a mess. Mainly, there's code scattered around places where they shouldn't belong and token implementation (token.c) is already of a bloat in itself as it is. The file has over 6k lines and it's subject to grow exponentially with improvements, features, whatever that is.
With that being said, the token implementation code in the kernel will be split accordingly and rest of the code moved to appropriate places. The new layout will look as follows (excluding the already existing files):
- client.c (Client security implementation code)
- objtype.c (Object type list implementation code -- more code related to object types will be put here when I'm going to implement object type access checks in the future)
- subject.c (Subject security context support)
The token implementation in the kernel will be split in 4 distinct files as shown:
- token.c (Base token support routines)
- tokenlif.c (Life management of a token object -- that is Duplication, Creation and Filtering)
- tokencls.c (Token Query/Set Information Classes support)
- tokenadj.c (Token privileges/groups adjusting support)
In addition to that, tidy up the internal header and reorganize it as well.
Fix MiInsertSharedUserPageVad to not charge the system process pool quota.
Even though PsChargeProcessNonPagedPoolQuota itself checks if the process specified is the system process, this doesn't work here as we're too early into boot for the kernel to know what the system process is.
This commit fully implements the inner logic of KeSaveFloatingPointState and KeRestoreFloatingPointState routines. On ReactOS we're currently simply doing a FNSAVE operation whereas on Windows it is a lot more than that.
On Windows Server 2003 the logic more or less goes like this. In order to save the FPU state the NPX state of the current thread has to be checked first, that is, if NPX is loaded and currently charged for the current thread then the system will acquire the NPX registers actively present. From that point it performs either a FNSAVE or FXSAVE
if FX is actually supported. Otherwise the control word and MXCsr registers are obtained.
FXSAVE/FNSAVE operation is done solely if the FX save area is held up in a pool allocation. Pool allocation occurs if it's been found out that the NPX IRQL of the thread is not the same as the current thread which from where it determines if the interrupt level is APC then allocate some pool memory and hold the save area there, otherwise
the save area in question is grabbed from the current processor control region. If NPX is not loaded for the current thread then the FPU state is obtained from the NPX frame.
In our case we'll be doing something way simpler. Only do a FXSAVE/FNSAVE directly of the FPU state registers, in this way we are simplifying the code and the actual logic of Save/Restore mechanism.
This is needed to store FPU state information when saving or restoring the floating point state of a system due to a call to KeSaveFloatingPointState or KeRestoreFloatingPointState.
- Add a check for correct PDO before doing anything
- Process the request only for started devices
- Send the request synchronously during the start sequence
This makes Windows' i8042prt.sys work on ReactOS.
Addendum to cf0bc1c132
The problem is that EndMem is changed to point to the DynamicPart of
the token, but the code after that expects it to still point into the
VariablePart instead.
Problem fixed by moving the insertion of RestrictedSids much sooner
(where the original ones are also being copied).
Shared locking must be used on the source token as it is accessed for
reading only. This fixes in particular the kmtest SeTokenFiltering that
would hang otherwise on a (wrong) exclusive locking.
- SepPerformTokenFiltering(): Always shared-lock the source token.
Its callers (NtFilterToken and SeFilterToken) just need to sanitize and
put the parameters in correct form before calling this helper function.
- Sync comments in NtFilterToken() with SeFilterToken().
This function is either called inter-kernel (in which case, all
parameters must be valid, and if not, we have to bugcheck), or, it
is called with **captured** parameters (from NtFilterToken) and those
latter ones are now expected to be valid and reside in kernel-mode.
Finally, data copied between token structures reside in kernel-mode
only and again are expected to be valid (if not, we bugcheck).
- The ACL is however not validated when the function is called within
kernel mode and no capture is actually being done.
- Simplify aspects of the function (returning early when possible).
