Addendum to commit de81021ba.
Otherwise, we get the following build error:
\ntoskrnl\kd64\kddata.c(532,5): error: initializer element is not a compile-time constant
PtrToUL64(RtlpBreakWithStatusInstruction),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
\ntoskrnl\kd64\kddata.c(526,26): note: expanded from macro 'PtrToUL64'
#define PtrToUL64(x) ((ULPTR64)(x))
^~~~~~~~~~~~
If you ask why there are two sets of functions that do the same, it's
because this file (and the kdmain.c) will very soon some day be moved to
a transport dll, outside the kernel, and it will need these functions.
See this command's documentation:
https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/-dbgprint
and the section "DbgPrint buffer and the debugger"
https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/reading-and-filtering-debugging-messages#dbgprint-buffer-and-the-debugger
for more details.
- Loosely implement the function, based on our existing circular printout
buffers in kdio.c.
- Enable its usage in the KdpPrint() and KdpPrompt() functions.
Notice that this function will *only* capture the strings being sent **to**
the debugger, and not the strings the debugger itself produce. (This means
that we cannot use the KdPrintCircularBuffer as a replacement for our
KDBG dmesg one, for example...)
How to test:
Run ReactOS under WinDbg, and use the !dbgprint command to view the
buffer. You can also use the Memory Window, place yourself at the
address pointed by KdPrintCircularBuffer and KdPrintWritePointer, and
read its contents.
What you should observe:
Prior notice: The circular buffer in debug builds of ReactOS and Windows
is 0x8000 bytes large. In release builds, its size is down to 0x1000.
1- When you start e.g. the 2nd-stage GUI installation of ReactOS, going
past the initial "devices installation" and letting it stabilize on
the Welcome page, break into WinDbg and run the !dbgprint command. You
should notice that the end of its output is weirdly truncated, compared
to what has been actually emitted to the debug output. Comparing this
with the actual contents of the circular buffer (via Memory Window),
shows that the buffer contents is actually correct.
2- Copy all the text that has been output by the !dbgprint command and
paste it in an editor; count the number of all characters appearing +
newlines (only CR or LF), and observe that this number is "mysteriously"
equal to 16384 == 0x4000.
3- Continue running ReactOS installation for a little while, breaking back
back into WinDbg and looking at !dbgprint again. Its output seems to be
still stopping at the same place as before (but the actual buffer memory
contents shows otherwise). Continue running ROS installation, and break
into the debugger when ROS is about to restart. You should now observe
that the dbgprint buffer rolled over:
dd nt!KdPrintRolloverCount shows 1.
Carefully analysing the output of !dbgprint, however, you will notice
that it looks a bit garbage-y: the first part of the output is actually
truncated after 16384 characters, then you get a second part of the
buffer showing what ReactOS was printing while shutting down. Then
you get again what was shown at the top of the !dbgprint output.
(Of course, comparing with the actual contents of the circular buffer
in memory shows that its contents are fine...)
The reason of these strange observations, is because there is an intrinsic
bug in the !dbgprint command implementation (in kdexts.dll). Essentially,
it displays the contents of the circular buffer in two single dprintf()
calls: one for the "older" (bottom) part of the buffer:
[WritePointer, EndOfBuffer]
and one for the "newer" (upper) part of the buffer:
[CircularBuffer, WritePointer[ .
The first aspect of the bug (causing observation 3), is that those two
parts are not necessarily NULL-terminated strings (especially after
rollover), so for example, displaying the upper part of the buffer, will
potentially also display part of the buffer's bottom part.
The second aspect of the bug (explaining observations 1 and 2), is due
to the implementation of the dprintf() function (callback in dbgenv.dll).
There, it uses a fixed-sized buffer of size 0x4000 == 16384 characters.
Since the output of the circular buffer is not done by little chunks,
but by the two large parts, if any of those are larger than 0x4000 they
get truncated on display.
(This last observation is confirmed in a completely different context by
https://community.osr.com/discussion/112439/dprintf-s-max-string-length .)
But the underlying GCC stupidity is still there (15 years later).
However, enable it only in 32-bit GCC builds, not in 64-bits nor with MSVC.
See commit b9cd3f2d9 (r25845) for some details.
GCC is indeed still incapable of casting 32-bit pointers up to 64-bits,
when static-initializing arrays (**outside** a function) without emitting
the error:
"error: initializer element is not constant"
(which might somehow indicate it actually tries to generate executable
code for casting the pointers, instead of doing it at compile-time).
Going down the rabbit hole, other stupidities show up:
Our PVOID64 type and the related POINTER_64 (in 32-bit archs), or the
PVOID32 and POINTER_32 (in 64-bit archs), are all silently broken in
GCC builds, because the pointer size attributes __ptr64 and __ptr32,
which are originally MSVC-specific, are defined to nothing in _mingw.h.
(And similarly for the __uptr and __sptr sign-extension attributes.)
Clang and other sane ompilers has since then implemented those (enabled
with -fms-extensions), but not GCC. The closest thing that could exist
for GCC is to do:
#define __ptr64 __attribute__((mode(DI)))
in order to get a 64-bit-sized pointer type with
typedef void* __ptr64 PVOID64;
but even this does not work, with the error:
"error: invalid pointer mode 'DI'"
Choose the correct element of the KiUnexpectedRange array,
depending on the interrupt vector, the same way as here:
a2c6af0da4/ntoskrnl/ke/amd64/except.c (L77)
And guard KeConnectInterrupt() execution with dispatcher lock.
CORE-14922
- Line-wrapping is enabled with 'ESC[?7h' (the '?' was forgotten).
Notice that the following reference also shows it wrong:
https://www.cse.psu.edu/~kxc104/class/cse472/09s/hw/hw7/vt100ansi.htm
- Terminal type is actually queried with 'ESC Z' (VT52-compatible), or
with 'ESC[c' (VT100-compatible). The antediluvian CTRL-E ('\x05')
control code gives instead a user-configurable (usually empty) string,
so it's not reliable.
Also, we don't really care about the returned result, we just need to
know that one has been sent.
Cross-checked with online documentation:
* "Digital VT100 User Guide" (EK-VT100-UG-001) (1st edition, August 1978,
reviewed November 1978).
* https://www.real-world-systems.com/docs/ANSIcode.html
* https://geoffg.net/Downloads/Terminal/TerminalEscapeCodes.pdf
* https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
* https://en.wikipedia.org/wiki/Enquiry_character
- Retrieve the size of the *controlling terminal* with escape sequences
only when it's a serial one: serial output is enabled *and* KDSERIAL
is set (i.e. user input through serial). See code for the actual logic
(the corresponding truth table is left as an exercise for the reader).
- Fix also a "Buffer" vs. "InBuffer" mismatch, that caused the whole
code to fail.
- For fallback terminal size values, use meaningful ones when SCREEN
is instead the controlling "terminal" (based on full-size BOOTVID
values).
- When echoing read characters during line-cooking, do direct output by
using KdpDprintf() instead of going through the heavy KdbpPrint() function.
This fixes some input artifacts like: 1. extra slowdowns due to
querying terminal size at each keypress, and 2. getting obnoxious
"--- Press q to abort ..." prompts in the middle of typing a long
comamnd because you are at the very bottom of the screen.
- Remove KdbInit() macro and directly use KdbpCliInit() (since the place
where it was used was already within an #ifdef KDBG block).
- Declare KdpKdbgInit() only when KDBG is defined, move its definition
into kdio.c and remove the legacy wrappers/kdbg.c file.
And in KdbInitialize(), set KdpInitRoutine directly to the former,
instead of using the KdpKdbgInit indirection.
- Don't reset KdComPortInUse in KdpDebugLogInit().
- Minor refactorings: KdpSerialDebugPrint -> KdpSerialPrint and make it
static; argument name "Message" -> "String", "StringLength" -> "Length".
What we have:
- Maximum number of pagefiles: 16
- Minimum pagefile size: 256 pages (1 MB when page size = 4096 bytes)
- Maximum pagefile size:
* 32-bit platforms: (1024 * 1024 - 1) pages (~ 4095 MB)
* x86 with PAE support: same size as for AMD x64
* x64 platform: (4 * 1024 * 1024 * 1024 - 1) pages (~ 16 TB)
* IA64 platform: (8 * 1024 * 1024 * 1024 - 1) pages (~ 32 TB)
Those are the values as supported and verified by the NT kernel.
Now, user-mode programs (including SMSS.EXE) have different opinions
on these, namely, they consider estimates directly in MB, respectively:
4095 MB, (16 * 1024 * 1024) MB, and (32 * 1024 * 1024) MB
(verified on Win2k3 and Win7 32 and 64 bits).
Also here, the minimum pagefile size is set to 2 MB.
Starting Windows 8+ (and 10), those values change slightly, and are
still not fully synchronized between NTOS:MM and SMSS. Finally, while
(x86 PAE and) AMD64 and ARM64 seem to share the maximum pagefile
size limit, 32-bit ARMv7 appears to use different limits than regular
x86 (2 GB instead of 4).
Please keep those values as they are for NT compatibility!
See the following references:
https://www.geoffchappell.com/studies/windows/km/ntoskrnl/api/mm/modwrite/create.htmhttps://techcommunity.microsoft.com/t5/ask-the-performance-team/what-is-the-page-file-for-anyway/ba-p/372608
+ Manual extraction of the values from different NT 6.2,6.3,10 builds.
[SMSS] Fill out in particular the x86-specific case for PAE.
[NTOS:MM] Some cleanup in the NtCreatePagingFile() code, namely:
- Clarify some comments;
- Validate the lower and upper bounds of the Minimum and Maximum sizes
(based on Windows behaviour as explained by Geoff + manual tests).
- Open the pagefile in case-insensitive;
- Simplify the loop that finds an existing matching pagefile;
- Simplify some failure exit paths;
- Add a "Missing validation steps TODO" comment block explaining the
existing code-hole.
The "failed to grant access rights" message isn't enough to understand what kind of access rights haven't been granted and why. Dumping information of the captured security descriptor, the ACL and its ACEs with mask rights and token SIDs should be enough to understand the reason of the failure in question.
debug.c will serve as a centralized facility for security debugging routines and everything related to that. This file will be expanded with further debug functions for the Security subsystem if needed.
Return TRUE instead of NTSTATUS code which has a value of FALSE and may confuse caller.
Fixes sporadic 0x7B bugcheck when booting from corrupted NTFS volume using WinXP ntfs.sys.
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).
If inserting the allocated VAD fails, MiMapViewOfDataSection will make no attempt to free the allocated VAD. Nor will it call MiDereferenceControlArea(ControlArea); like other failure return paths. This commit fixes this behavior.
Co-authored-by: Hermès BÉLUSCA - MAÏTO <hermes.belusca-maito@reactos.org>
We are allocating blocks of pool memory for a security descriptor with its own specific tag, TAG_SEC_QUERY, so just use it when freeing when releasing the descriptor as well (aka freeing the said pool).
There are two fundamental problems when it comes to access checks in ReactOS. First, the internal function SepAccessCheck which is the heart and brain of the whole access checks logic of the kernel warrants access to the calling thread of a process to an object even though access could not be given.
This can potentially leave security issues as we literally leave objects to be touched indiscriminately by anyone regardless of their ACEs in the DACL of a security descriptor. Second, the current access check code doesn't take into account the fact that an access token can have restricted SIDs. In such scenario we must perform additional access checks by iterating over the restricted SIDs of the primary token by comparing the SID equality and see if the group can be granted certain rights based on the ACE policy that represents the same SID.
Part of SepAccessCheck's code logic will be split for a separate private kernel routine, SepAnalyzeAcesFromDacl. The reasons for this are primarily two -- such code is subject to grow eventually as we'll support different type ACEs and handle them accordingly -- and we avoid further code duplicates. On Windows Server 2003 there are 5 different type of ACEs that are supported for access checks:
- ACCESS_DENIED_ACE_TYPE (supported by ReactOS)
- ACCESS_ALLOWED_ACE_TYPE (supported by ReactOS)
- ACCESS_DENIED_OBJECT_ACE_TYPE
- ACCESS_ALLOWED_OBJECT_ACE_TYPE
- ACCESS_ALLOWED_COMPOUND_ACE_TYPE
This gives the opportunity for us to have a semi serious kernel where security of objects are are taken into account, rather than giving access to everyone.
CORE-9174
CORE-9175
CORE-9184
CORE-14520
SepSidInTokenEx function already provides the necessary mechanism to handle scenario where a token has restricted SIDs or a principal SID is given to the call. There's no reason to have these redundant ASSERTs anymore.
In addition to that make sure if the SID is not a restricted and if that SID is the first element on the array and it's enabled, this is the primary user.
This function will be used to retrieve a security identifier from a valid access control entry in the kernel. Mostly and exclusively used within access checks related code and such.
Implement the correct start-stop sequence for resource rebalancing
without the actual rebalancing. Also move IoInvalidateDeviceState
processing into the enumeration thread as it should be.
CORE-17519
Implement initial token debug code. For now debug information that is being tracked are: process image file name, process and thread client IDs and token creation method. More specific debug code can be added later only if needed.
As for the token creation method, this follows the same principle as on Windows where the creation method is defined by a value denoting the first letter of the said method of creation. That is, 0xC is for token creation, 0xD is for token duplication and 0xF is for token filtering. The debug field names are taken from Windows PDB symbols for WinDBG debug extension support purposes. The names must not be changed!
- Add a new cmboot.h header to isolate the boot-support definitions
shared with the NT/ReactOS bootloader.
- Move CmpFreeDriverList() to cmboot.c so that we can use it for
cleanup paths in the NT/ReactOS bootloader.
- CmpFindControlSet(): Directly build the control set name in UNICODE,
instead of doing an ANSI->UNICODE conversion.
- Directly assign the CurrentControlSet\Services constant string,
instead of going the route of init-empty-string + append-string.
This is possible since that string is not modified later.
- Remove ASSERT(FALSE), replacing them with correct failure handling.
- Add cleanup paths in CmpAddDriverToList().
- Simplify and fix CmpFreeDriverList(): it's the full DriverNode
that needs to be freed; not the LIST_ENTRY pointer.
- Add other validity checks:
* Registry value types and data sizes;
* For multi-strings, verify that they are NULL-terminated.
* For (multi-)strings, check whether they are NULL-terminated before
optionally removing their trailing NULL character from the count.
Check also whether they are of zero-length and take appropriate
action where necessary.
- Add CmpIsDriverInList() for future usage in CMBOOT compiled in
bootloader mode.
- Add SAL annotations and Doxygen documentation.
- Add debug traces.
- Formatting / code style fixes.
** TODO: Fix SafeBoot support **
Always create only non-volatile (sub)keys when registering a new device interface, so then they are saved after reboot.
On Windows, nearly all device interface keys are non-volatile, except the "Control" subkey, which is managed by IoSetDeviceInterfaceState instead.
In particular, it fixes MS sysaudio loading failure with MS audio drivers replacement (ks, portcls, swenum, sysaudio, wdmaud). My IoGetDeviceInterfaceAlias implementation is also required to be applied. MS sysaudio implementation(s) except that those keys are non-volatile (but we're creating them volatile instead), and trying to create a subkey(s) there (via other IoDeviceInterface* routines), to read/write some needed data. But then they fail to do that with STATUS_CHILD_MUST_BE_VOLATILE (0xc0000181), obviously because our keys are volatile.
The volatile keys can never have non-volatile subkeys.
CORE-17361
- inbv.c now only contains the Inbv-specific API and nothing else.
- It will make easier for people to write their own boot themes & animations,
by just copying/adapting the bootanim.c file (and the resources).
- Add SAL annotations.
- All INBV progress bar functions (except for InbvIndicateProgress())
should not be INIT-only functions, since they can be (not yet in ROS)
used at later times -- namely, for feedback during hibernation.
In particular, the progress percentage specified to InbvUpdateProgressBar(),
or the progress feedback made with InbvIndicateProgress() calls, is
**relative** to the progress sub-range specified with a previous call to
InbvSetProgressBarSubset() (by default, the range is 0...100%).
This functionality is used e.g. when the number of progress steps is
unknown prior, for example when loading drivers: in this case progress
is made within a given percentage range.
This bug has always been with us since 2010.
This reverts 8479509 commit which pretty much does nothing at all (the captured pointer is NULL within the stack of the function has no effect outside of the function). My mistake, sorry.
Whenever a captured security property such as privilege or SID is released, we must not have such captured property point at random address in memory but rather we must assign it as NULL after it's been freed from pool memory. This avoids potential double-after-free situations where we might release a buffer twice.
This is exactly the case with token filtering.
Before purging the data cache of a certain section of a file from system cache, we have to unintialize the private cache maps of that section if a filesystem or any other component prompts the kernel to do so.
Currently, these features are vital for the kernel:
- CPUID instruction
- CMPXCHG8B instruction
- TSC aka Time Stamp Counter
All of that have to be present on i586
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.
Ensure that when we're cleaning up the EPROCESS object, that we are dereferencing the quota block the process in question was using. The routine will automatically request a quota block cleanup if the process that dereferenced the quota block was the last.
-- Rewrite PspChargeProcessQuotaSpecifiedPool and PspReturnProcessQuotaSpecifiedPool private kernel routines, with the goal to implement the algorithms necessary to manage the fields of quota blocks (Usage, Return, Limit and Peak).
-- Invoke the Mm if quota limit raising or returning has to be done
-- When destroying a quota block, make sure that we're giving back all the rest of non-returned quotas to Memory Mm
-- Crash the system with QUOTA_UNDERFLOW if someone is returning way too much quota than it was previously charged
-- When a process exits, ensure that it doesn't hold up any charged quotas in QuotaUsage field of the process object, that way we're enforcing proper kernel consistency
-- Implement PsChargeSharedPoolQuota and PsChargeProcessPageFileQuota functions, used exclusively by the Object Manager. These routines are used to charge or return amount of quotas of a newly created object.
-- On PspInheritQuota, when assigning to process the default quota block if no parent process is given, we must increment the reference counts as we're using it
-- Handle the ProcessCount reference field, as it wasn't used
-- Annotate the functions with SAL
-- Document the code
=== REMARKS ===
Windows LogOn (Winlogon) is responsible for setting up a different quota block for all the processes within an interactive session, which is what we don't do. What we're currently doing instead is we're using the default block, PspDefaultQuotaBlock, for all the processes
across the system. The default block contains the default limits of -1 (which would imply no limits). By definition, the kernel won't ever return STATUS_QUOTA_EXCEEDED as we literally don't set up a definite limit for regular processes. This situation has to be tackled
in the future.
=== TODO FOR FUTURE ===
Most of the code in PspChargeProcessQuotaSpecifiedPool and PspReturnProcessQuotaSpecifiedPool private routines must be refactored in order to reduce the usage of the quota spin lock, possibly wrapping such code in a loop and whatnot.
CORE-17784
This implements both MmRaisePoolQuota and MmReturnPoolQuota functions, which serve exclusively for quota pool management. The process manager communicates with the memory manager in a call of need to charge or return pool quota limits.
OBP_SYSTEM_PROCESS_QUOTA is a macro that'll be used as a way to assign a dummy quota block to system processes, as we mustn't do anything to those in case the Object Manager is charging or returning pool quotas.
Declare PsReturnSharedPoolQuota and PsChargeSharedPoolQuota prototypes and annotate the functions. Furthermore, add two definitions related to quota pool limits threshold -- PSP_NON_PAGED_POOL_QUOTA_THRESHOLD and PSP_PAGED_POOL_QUOTA_THRESHOLD. For further details, see the commit description of "[NTOS:MM] Add the pool quota prototypes and some definitions".
Declare the MmRaisePoolQuota and MmReturnPoolQuota prototypes in the header and add some definitions related to pool quotas, namely MmTotalNonPagedPoolQuota and MmTotalPagedPoolQuota. These variables are used internally by the kernel as sort of "containers" (for the lack of a better term)
which uphold the amount of quotas that the Process Manager is requesting the Memory Manager to raise or return the pool quota limit. In addition to that, add some definitions needed for both of these functions.
The definitions, MI_CHARGE_PAGED_POOL_QUOTA and MI_CHARGE_NON_PAGED_POOL_QUOTA respectively, bear some interesting aspect. Seemingly the 0x80000 and 0x10000 values (that would denote to 524288 and 65536 specifically) are used as quota "limits" or in other words, thresholds that the kernel
uses. So for example if one would want to raise the quota limit charge, MmRaisePoolQuota will raise it so based on this formula -- NewMaxQuota = CurrentQuota + LIMIT_VALUE. LIMIT_VALUE can be either MI_CHARGE_PAGED_POOL_QUOTA or MI_CHARGE_NON_PAGED_POOL_QUOTA, depending a per quota pool basis.
What's more interesting is that these values are pervasive in Process Manager even. This is when quotas are to be returned back and trim the limit of the quota block if needed, the kernel would either take the amount provided by the caller of quotas to return or the threshold (paged or not paged)
if the amount to return exceeds the said threshold in question.
This fixes an issue where ReactOS would assert on QuotaUsage == 0 as the process was still taking up quotas during a quota block de-reference with root cause of ThisBufferLength member field being 0 which made process quota charging/returning flow unbalanced.
In addition to that, on FsRtlCancelNotify routine API all we must ensure that if PsChargePoolQuota or ExAllocatePoolWithTag function fails we have to handle the raised exceptions accordingly and return the charged quota back (if we actually charged quotas that is). With said, wrap that part of code with SEH.
=== DOCUMENTATION REMARKS ===
The cause of the assert is due to the fact ThisBufferLength was being handled wrongly ever since, until this commit. When FsRtl of the Executive has to filter reported changes (with logic algorithm implemented in FsRtlNotifyFilterReportChange function), the said function will charge the quota of a given process
with an amount that is represented as the buffer length whose size is expressed in bytes. This length buffer is preserved in a local variable called NumberOfBytes, which is initialized from BufferLength member field of notification structure or from the length from stack parameters pointed from an IRP.
As it currently stands, the code is implemented in such a way that FsRtlNotifyFilterReportChange will charge quotas to a process but it doesn't assign the buffer length to ThisBufferLength. On the first glimpse ThisBufferLength and BufferLength are very similar members that serve exact same purpose but in reality there's a subtle distinction between the two.
BufferLength is a member whose length size is given by FSDs (filesystem drivers) during a notification dispatching. Whenever FsRtl receives the notification structure packed with data from the filesystem, the length pointed by BufferLength gets passed to ThisBufferLength and from now on the kernel has to use this member for the whole time of its task to accomplish
whatever request it's been given by the filesystem. In other words, BufferLength is strictly used only to pass length size data to the kernel by initializing ThisBufferLength based on that length and unequivocally the kernel uses this member field. What we're doing is that ThisBufferLength never receives the length from BufferLength therefore whenever FsRtl component
has to return quotas back it'll return an amount of 0 (which means no amount to return) and that's a bug in the kernel.
Also generate processor identifier properly based on this value
on the Configuration Manager machine-dependent initialization.
Update processor driver INF file accordingly.
CORE-17970 CORE-14922
We have a special file, tag.h, which serves as a place to store whatever kernel pool allocation tag yet we still have some tags sparse over the kernel code... So just re-group them in one unique place.
SIDs are variadic by nature which means their lengths can vary in a given amount of time and certain factors that allow for this happen. This also especially can lead to issues when capturing SIDs and attributes because SeCaptureSidAndAttributesArray might end up overwriting the buffer during the time it's been called.
Therefore when we're copying the SIDs, validate their lengths. In addition to that, update the documentation header accordingly and add some debug prints in code.
NormalContext and NormalRoutine are just for good measure, but
SystemArgument2 is actually used by the function.
And yes, this appears to be a bug in Win 2003.
This implements the support of token filtering within the kernel, where the kernel can create restricted tokens of regular ones on demand by the caller. The implementation can be accessed thorough a NT syscall, NtFilterToken, and a kernel mode routine, SeFilterToken.
The continue statements do not server any useful purpose in these loops so they're basically pointless. These have been introduced by mistake so my bad.
A scenario where it happens that an access token belongs to an administrators group but it's disabled (that is, SeAliasAdminsSid has no attributes or it doesn't have SE_GROUP_ENABLED turn ON), the function removes this group from the token but still has TOKEN_HAS_ADMIN_GROUP flag which can lead to erratic behavior across the kernel and security modules -- implying that the token still belongs to administrators group.
This is an oversight from my part.
Only resources of HAL were checked against conflicts, not those of PnP Manager
Let IoReportResourceForDetection() make a silent conflict check.
Otherwise IopCheckResourceDescriptor() will always return 'no conflict'.
CORE-17789
Previous code did not detect equal resource ranges as conflicting.
Thanks Hervé Poussineau for pointing this out!
Meanwhile, simplify the code to make it more readable.
In SeCaptureLuidAndAttributesArray we must ensure that we don't go onto a potential integer overflow scenario by checking against the maximum limit threshold the kernel states. In addition, write an explicit name macro for the value.
Certainly due to copy-pasta error from the original code.
A consequence of this oversight, was that the IoGetDeviceObjectPointer()
calls on these device names, in fltmgr!DriverEntry() couldn't work.
(See drivers/filters/fltmgr/Interface.c, line 1880 and below.)
- 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.
The function might assign the flag yet it could possibly fail on creating a DACL and insert an "access allowed" right to the access entry within the DACL. In this case, make sure we actually succeeded on all the tasks and THEN assign the flag that the DACL is truly present.
Also, make sure that the Current buffer size variable gets its new size so that we avoid overidding the memory of the DACL if the security descriptor wants both a DACL and SACL and so that happens that the DACL memory gets overwritten by the SACL.
Implement the portion chunk of code that is responsible for setting the system access control list (SACL) to the World security descriptor, based from SeWorldSid (World security identifier).
Addendum to 608032bd and 835c3023.
The IRQL is actually raised by KeFreezeExecution() and lowered by
KeThawExecution(), always to HIGH_IRQL on MP systems, or if necessary
on UP. These functions are called respectively by KdEnterDebugger()
and KdExitDebugger().
When performing access security check, use the security descriptor that we've captured it to determine based on that descriptor if the client can be granted access or not.
As we now have the SEF_* flags declared within the SDK we can simply check for such flags directly wihout having to check for the hard-coded flag values.
This implements the EffectiveOnly option of SepDuplicateToken routine (used by NtDuplicateToken syscall and other functions alike) which makes the access token effective by removing the disabled parts like privileges and groups.
Fix a wrong returned datatype of the function, as SepSinglePrivilegeCheck calls the internal private SepPrivilegeCheck function which returns a BOOLEAN value.
When processing:
Make sure that the process is not terminating.
Make sure that the process WorkingSet is still valid
Protect accessing & writing to PTEs by acquiring the working set lock
CORE-17595 CORE-17642
When creating or duplicating an access token object, make sure that the logon session is getting referenced by the token must be inserted onto the logon reference member (a.k.a LogonSession) for proper logon session referencing tracking.
Also when a token object is about to be destroyed or that we are taking away a reference session from it, we must ensure that the referenced logon session data gets removed from the token in question.
CORE-17700
When duplicating an access token, the authentication ID is already copied from the existing token to the new one anyway so there's no point on having the commented call still left in the code.
Note to SELF and EVERYONE: the commit implements the initial logon session termination notification implementation, the SeMarkLogonSessionForTerminationNotification function, but as it currently stands there are several other tasks to be addressed in the future in order for the logon termination notification to be fully completed. The tasks as of which are.
1. Our SepRmDereferenceLogonSession is not fully implemented, as it doesn't inform the LSA and filesystems of logon deletion notification
2. Implement two worker routines that are actually in charge of such tasks of informing LSA and FSDs
3. Perform logon deletion
4. Do further investigations and check whatever that is left to address, if any
* Quality of service kernel stuff bears nothing with security descriptors in anyway, so just have a file specifically for it
* Annotate the function arguments parameters with SAL
* Document the functions
Use REG_OPTION_NON_VOLATILE instead of REG_OPTION_VOLATILE in all ZwCreateKey calls of OpenRegistryHandlesFromSymbolicLink, since the keys created/opened by this function, should be non-volatile (in other words, be saved after reboot).
Also Device Parameters subkey that is created in IoOpenDeviceInterfaceRegistryKey (which uses that routine as well), is non-volatile too, so the parent keys whose contain it, cannot be volatile.
It will fix an error with status 0xc0000181 (STATUS_CHILD_MUST_BE_VOLATILE) occuring during loading kernel mode audio drivers from Windows XP/2003, especially checked (debug) versions, with my IoGetDeviceInterfaceAlias implementation. Also it may fix other error cases.
CORE-17361
We allocate memory pool for a new security descriptor with specific info filled by the caller but we don't set the control flag bits for the newly allocated descriptor, which is wrong. Originally spotted by Vadim Galyant.
CORE-17650
KD64: Raise to HIGH_LEVEL when entering trap
KDBG: lower to DISPATCH_LEVEL when applying IRQL hack & use a worker thread to load symbols
KD&KDBG: Actually unload symbols when required
Raise IRQL before entering debugger, so that KeAcquireSpinLockAtDpcLevel works as expected.
- HIGH_LEVEL since we don't know where we are coming from.
Do not try to read debug symbol from files in KDBG.
- There is no reason that this works if Mm didn't map it in the first place.
GCC has some functions, variables & type attributes which can be used as aliases
for some of the SAL annotations. Although it's not as rich & precise, it's still useful
since we actually enable -Werror on GCC builds whereas we don't use such an option
on MSVC builds.
For now, _Must_inspect_result_ is aliased to warn_result_unused attribute.
