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Comments
Same question after 19 years...
And the same answer I've been giving to such questions for that time: Did you try Google? There are, literally, 197,000 results when I entered this query.
Peter
(OK... after rethinking my wise-guy answer: Have you tried IOCTL_STORAGE_QUERY_PROPERTY?)
Peter Viscarola
OSR
@OSRDrivers
......and, out of these 197,000 results, IFengHuang somehow managed to find the one that points to the question that, for some reason, was left unanswered on NTDEV, and decided to "revive" the thread that had been resting in peace for 19(!!!) fucking years. Sounds incredible, but that's the way it is.......
Anton Bassov
https://i.pinimg.com/originals/0d/c0/ad/0dc0adc947663e9bf31365edde44424c.gif
Peter Viscarola
OSR
@OSRDrivers
I'm so sorry for "Dig Grave".
After referring to this article, I got a solution.
The following is my code, leave it for those who need it in the future.
[MODS: Updated sample provided by author below]
Thank you for coming back to us and showing the solution. That's very nice of you! MUCH appreciated.
Peter
Peter Viscarola
OSR
@OSRDrivers
Where did you get this code? The "AllocRetry" thing here is an abomination that shows a fundamental misunderstanding. If your system is so short on non-paged pool that you can't allocate these small structures, then your system is going down. Retries won't help, and they are silly for a request as trivial as this one. Some people added these retry functions to try to work around the "low-memory simulation" in Driver Verifier, but the WHOLE POINT of that test is to make sure your driver handles a low-memory situation gracefully. By retrying like this, you never test your low-memory path.
You should eliminate AllocRetry and replace it with ExAllocatePoolXxx. It's not clear to me why you need non-paged pool here, either. ZwCreateFile requires PASSIVE_LEVEL, so you'll be able to handle paged pool.
Tim Roberts, [email protected]
Providenza & Boekelheide, Inc.
The code is referring to this article, then I modify it into kernel mode.
Thank you for pointing out the shortcomings. I'll modify the code later.
By the way, but I saw many alloc-retry-like macro inside WFPSampler codes, why do they write like that?
I find that I can't edit my comment anymore.
Yup! By design. You have one hour to edit something you post. After that, you've got to me a mod to edit anything.
If the screen cap you posted is what you're referring to, this isn't an alloc-retry... it's using a "safe multiplier" function to detect/avoid an overrun during the multiply.
Having said that, I'm not sure why -- after calling RtlSizeTMult and checking for success -- he needs to check that the allocated size is >= the plain multiplied (count * sizeof) size... but "whatever"...
Peter
Peter Viscarola
OSR
@OSRDrivers
OTOH, if you're referring to this:
That is some of the dumbest code I've seen in a very long time. Whoever wrote that tight loop calling ExAllocatePool over and over again should be .... I dunno. Something.
Peter
Peter Viscarola
OSR
@OSRDrivers
I want to fix my code above for removing
AllocRetry
.. How can I do that now ?Just call ExAllocatePool instead of AllocRetry. I think Mr. Roberts May have suggested this already.
Peter
Peter Viscarola
OSR
@OSRDrivers
That is very considerate. Why not post an updated version below?
Peter
Peter Viscarola
OSR
@OSRDrivers
Concise, neat and centralized code which showing in the forum is very important for me, especially for those who are eager to find an off-the-shelf solution (like me).
Here is the fixed version:
And I have removed the code sample from your earlier post and pointed people to this post.
Thank you for your concern for future people searching for this info. It is very good of you to do this... too few people are willing to share with others. They only care for their question to be answered. So.... thanks!
Peter
Peter Viscarola
OSR
@OSRDrivers
Well, the example of AllocRetry() in your code seems to be a pretty good demo of why copy-pasting "off-the-shelf solutions" may be not- so- good idea - after all, you did not come up with this "pearl" yourself, did you. Instead, you have modeled it upon some existing sample......
Anton Bassov
@Peter_Viscarola_(OSR) said:
It's practically right but slightly imperfect.
In some cases (i can said - in MANY cases) you will have not the exact serial number but its decoration in form of hexadecimal representation.
P.S. If we need this number just for some unique persistent value it's good idea to concatenate it with Vendor and Product...
Hello tried this code and works ok on windows 8 vmware but on windows 10 vmware had to modify it a bit to work because of bsod. But on real windows 10 got bsod - page fault in non paged area. Tested it on vmware is ok but on real host this bsod do you have an idea why it is very hard to debug on real pc.
!analyze -v
PAGE_FAULT_IN_NONPAGED_AREA (50)
Invalid system memory was referenced. This cannot be protected by try-except.
Typically the address is just plain bad or it is pointing at freed memory.
Arguments:
Arg1: ffffffff80002c70, memory referenced.
Arg2: 0000000000000000, value 0 = read operation, 1 = write operation.
Arg3: fffff8041c9d23d5, If non-zero, the instruction address which referenced the bad memory
address.
Arg4: 0000000000000002, (reserved)
Debugging Details:
*** WARNING: Unable to verify timestamp for gethwid.sys
Could not read faulting driver name
*** WARNING: Unable to verify timestamp for win32k.sys
KEY_VALUES_STRING: 1
BUGCHECK_CODE: 50
BUGCHECK_P1: ffffffff80002c70
BUGCHECK_P2: 0
BUGCHECK_P3: fffff8041c9d23d5
BUGCHECK_P4: 2
READ_ADDRESS: fffff8041d2fb390: Unable to get MiVisibleState
Unable to get NonPagedPoolStart
Unable to get NonPagedPoolEnd
Unable to get PagedPoolStart
Unable to get PagedPoolEnd
fffff8041d20f380: Unable to get Flags value from nt!KdVersionBlock
fffff8041d20f380: Unable to get Flags value from nt!KdVersionBlock
unable to get nt!MmSpecialPagesInUse
ffffffff80002c70
MM_INTERNAL_CODE: 2
BLACKBOXBSD: 1 (!blackboxbsd)
BLACKBOXNTFS: 1 (!blackboxntfs)
BLACKBOXPNP: 1 (!blackboxpnp)
BLACKBOXWINLOGON: 1
CUSTOMER_CRASH_COUNT: 2
PROCESS_NAME: System
TRAP_FRAME: ffff858082d8d8c0 -- (.trap 0xffff858082d8d8c0)
NOTE: The trap frame does not contain all registers.
Some register values may be zeroed or incorrect.
rax=ffff858082d8dac0 rbx=0000000000000000 rcx=ffff858082d8dcc0
rdx=0000000000000000 rsi=0000000000000000 rdi=0000000000000000
rip=fffff8041c9d23d5 rsp=ffff858082d8da50 rbp=ffff858082d8db50
r8=0000000000000000 r9=0000000000000000 r10=0000000000000000
r11=ffff858082d8df38 r12=0000000000000000 r13=0000000000000000
r14=0000000000000000 r15=0000000000000000
iopl=0 nv up ei ng nz na pe nc
nt!output_l+0x89:
fffff804
1c9d23d5 458a0c24 mov r9b,byte ptr [r12] ds:00000000
00000000=??Resetting default scope
STACK_TEXT:
ffff8580
82d8d618 fffff804
1ca4e27f : 0000000000000050 ffffffff
80002c70 0000000000000000 ffff8580
82d8d8c0 : nt!KeBugCheckExffff8580
82d8d620 fffff804
1c8a6960 : 0000000000000000 00000000
00000000 ffff858082d8d940 00000000
00000000 : nt!MiSystemFault+0x1898cfffff8580
82d8d720 fffff804
1ca05f5e : 0000000000000000 ffff8580
00000000 ffffb70917a9b1c0 ffff8807
0d1dcae0 : nt!MmAccessFault+0x400ffff8580
82d8d8c0 fffff804
1c9d23d5 : 0000000000000000 00000000
00000000 0000000000000000 00000000
00000000 : nt!KiPageFault+0x35effff8580
82d8da50 fffff804
1c9ce19a : 0000000000000020 00000000
00000000 ffff858082d8de10 fffff804
1ca097b8 : nt!output_l+0x89ffff8580
82d8dd10 fffff804
1c9ce121 : 000000000000007f ffff8580
82d8de10 ffff37403f844682 fffff804
1ca09620 : nt!vsnprintf_l+0x6affff8580
82d8dd80 fffff804
1c96f46b : ffff858082d8e470 ffff8807
00bd3500 ffff858082d8de40 fffff804
1c9ce08c : nt!vsnprintf+0x11ffff8580
82d8ddc0 fffff804
1c962c64 : 0000000000000000 00000000
00000080 0000000000000003 ffffb709
254925e0 : nt!RtlStringCbVPrintfA+0x3fffff8580
82d8ddf0 fffff804
1c962b3c : ffff8807002d0000 ffff8807
00bd3510 ffff858082d8e470 fffff804
1c9fbc30 : nt!vDbgPrintExWithPrefixInternal+0xe4ffff8580
82d8def0 fffff804
1d904c70 : ffffffff80002c70 00000000
00000000 ffff88070d1dcae0 ffffb709
0e652880 : nt!DbgPrint+0x3cffff8580
82d8df40 ffffffff
80002c70 : 0000000000000000 ffff8807
0d1dcae0 ffffb7090e652880 00000000
00000000 : gethwid+0x4c70ffff8580
82d8df48 00000000
00000000 : ffff88070d1dcae0 ffffb709
0e652880 0000000000000000 ffff8580
00000080 : 0xffffffff`80002c70SYMBOL_NAME: gethwid+4c70
MODULE_NAME: gethwid
IMAGE_NAME: gethwid.sys
STACK_COMMAND: .thread ; .cxr ; kb
BUCKET_ID_FUNC_OFFSET: 4c70
FAILURE_BUCKET_ID: AV_R_INVALID_gethwid!unknown_function
OS_VERSION: 10.0.19041.1
BUILDLAB_STR: vb_release
OSPLATFORM_TYPE: x64
OSNAME: Windows 10
FAILURE_ID_HASH: {5c1ae45c-6bee-516e-d466-f1bd94725f76}
Followup: MachineOwner
A bit difficult to see your screen from over here, but it appears to have blown up in a print. Looking at the code, this one seems most likely:
KdPrint(("SerialNumber: %s.\n", originSerialNumber));
Well, actually, the most likely detonation site is the part where you "had to modify it a bit".
In any case, you should load your driver symbols (.reload -f gethwid.sys) and then open the call stack window, double click on this function, open the locals and see what's what...
If you used the debug build, windbg would be happy to show you the line of code that failed.
Tim Roberts, [email protected]
Providenza & Boekelheide, Inc.
and the \n it was ok. But can you tell me why this happens with dbgprint?