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MdeModulePkg/PciBusDxe: Improve the flow of testing support attributes #1

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@niruiyu niruiyu commented Apr 4, 2023

https://bugzilla.tianocore.org/show_bug.cgi?id=3635

Currently, in order to test the supported attributes, the PciTestSupportedAttribute() will set the command register to 0x27 (EFI_PCI_COMMAND_IO_SPACE, EFI_PCI_COMMAND_MEMORY_SPACE, EFI_PCI_COMMAND_BUS_MASTER, EFI_PCI_COMMAND_VGA_PALETTE_SNOOP) firstly, and then read back to check whether these attributes are set successfully in the device.
This will cause the other enabled bits
(other than EFI_PCI_COMMAND_IO_SPACE,EFI_PCI_COMMAND_MEMORY_SPACE,
EFI_PCI_COMMAND_BUS_MASTER,EFI_PCI_COMMAND_VGA_PALETTE_SNOOP)
be cleared for a short of time
This patch fixes this issue by keeping the origina
enabled bits when setting 0x27.

Reviewed-by: Ray ray.ni@intel.com

https://bugzilla.tianocore.org/show_bug.cgi?id=3635

Currently, in order to test the supported attributes,
the PciTestSupportedAttribute() will set the command register
to 0x27 (EFI_PCI_COMMAND_IO_SPACE, EFI_PCI_COMMAND_MEMORY_SPACE,
EFI_PCI_COMMAND_BUS_MASTER, EFI_PCI_COMMAND_VGA_PALETTE_SNOOP) firstly,
and then read back to check whether these attributes are
set successfully in the device.
This will cause the other enabled bits
 (other than EFI_PCI_COMMAND_IO_SPACE,EFI_PCI_COMMAND_MEMORY_SPACE,
 EFI_PCI_COMMAND_BUS_MASTER,EFI_PCI_COMMAND_VGA_PALETTE_SNOOP)
 be cleared for a short of time
 This patch fixes this issue by keeping the origina
 enabled bits when setting 0x27.

Signed-off-by: xueshengfeng <xueshengfeng@byosoft.com.cn>
Reviewed-by: Ray <ray.ni@intel.com>
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niruiyu pushed a commit that referenced this pull request Nov 23, 2023
Root cause:
1. Before DisableReadonlyPageWriteProtect() is called, the return
address (#1) is pushed in shadow stack.
2. CET is disabled.
3. DisableReadonlyPageWriteProtect() returns to #1.
4. Page table is modified.
5. EnableReadonlyPageWriteProtect() is called, but the return
address (#2) is not pushed in shadow stack.
6. CET is enabled.
7. EnableReadonlyPageWriteProtect() returns to #2.
#CP exception happens because the actual return address (#2)
doesn't match the return address stored in shadow stack (#1).

Analysis:
Shadow stack will stop update after CET disable (DisableCet() in
DisableReadOnlyPageWriteProtect), but normal smi stack will be
continue updated with the function called and return
(DisableReadOnlyPageWriteProtect & EnableReadOnlyPageWriteProtect),
thus leading stack mismatch after CET re-enabled (EnableCet() in
EnableReadOnlyPageWriteProtect).

According SDM Vol 3, 6.15-Control Protection Exception:
Normal smi stack and shadow stack must be matched when CET enable,
otherwise CP Exception will happen, which is caused by a near RET
instruction.

CET is disabled in DisableCet(), while can be enabled in
EnableCet(). This way won't cause the problem because they are
implemented in a way that return address of DisableCet() is
poped out from shadow stack (Incsspq performs a pop to increases
the shadow stack) and EnableCet() doesn't use "RET" but "JMP" to
return to caller. So calling EnableCet() and DisableCet() doesn't
have the same issue as calling DisableReadonlyPageWriteProtect()
and EnableReadonlyPageWriteProtect().

With above root cause & analysis, define below 2 macros instead of
functions for WP & CET operation:
WRITE_UNPROTECT_RO_PAGES (Wp, Cet)
WRITE_PROTECT_RO_PAGES (Wp, Cet)
Because DisableCet() & EnableCet() must be in the same function
to avoid shadow stack and normal SMI stack mismatch.

Note: WRITE_UNPROTECT_RO_PAGES () must be called pair with
WRITE_PROTECT_RO_PAGES () in same function.

Change-Id: I4e126697efcd8dbfb4887da034d8691bfca969e3
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Zeng Star <star.zeng@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
niruiyu pushed a commit that referenced this pull request Apr 10, 2024
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4534

Bug Details:
PixieFail Bug #1
CVE-2023-45229
CVSS 6.5 : CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE-125 Out-of-bounds Read

Change Overview:

Introduce Dhcp6SeekInnerOptionSafe which performs checks before seeking
the Inner Option from a DHCP6 Option.

>
> EFI_STATUS
> Dhcp6SeekInnerOptionSafe (
>  IN  UINT16  IaType,
>  IN  UINT8   *Option,
>  IN  UINT32  OptionLen,
>  OUT UINT8   **IaInnerOpt,
>  OUT UINT16  *IaInnerLen
>  );
>

Lots of code cleanup to improve code readability.

Cc: Saloni Kasbekar <saloni.kasbekar@intel.com>
Cc: Zachary Clark-williams <zachary.clark-williams@intel.com>

Signed-off-by: Doug Flick [MSFT] <doug.edk2@gmail.com>
Reviewed-by: Saloni Kasbekar <saloni.kasbekar@intel.com>
@niruiyu niruiyu closed this May 10, 2024
@niruiyu niruiyu deleted the cpu/for_merge2 branch May 10, 2024 06:26
niruiyu pushed a commit that referenced this pull request Nov 14, 2024
This patch does not impact functionality. It aims to clarify the
synchronization flow between the BSP and APs to enhance code
readability and understanding:

Steps tianocore#6 and tianocore#11 are the basic synchronization requirements for all
cases.

Steps #1 is additional requirements if the MmCpuSyncModeTradition
mode is selected.

Steps #1, #2, #3, tianocore#4, tianocore#5, tianocore#7, tianocore#8, tianocore#9, and tianocore#10 are additional
requirements if the system needs to configure the MTRR.

Steps tianocore#9 and tianocore#10 are additional requirements if the system needs to
support the mSmmDebugAgentSupport.

Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
niruiyu pushed a commit that referenced this pull request Nov 14, 2024
… func

This patch is for PiSmmCpuDxeSmm driver to add one round wait/release sync
for BSP and AP to perform the SMM CPU Platform Hook before executing MMI
Handler: SmmCpuPlatformHookBeforeMmiHandler (). With the function, SMM CPU
driver can perform the platform specific items after one round BSP and AP
sync (to make sure all APs in SMI) and before the MMI handlers.

After the change, steps #1 and #2 are additional requirements if the
MmCpuSyncModeTradition mode is selected.

Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
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