Commit Graph

304 Commits

Author SHA1 Message Date
Star Zeng 4a7aa8d34a MdeModulePkg: Remove EmuVariableRuntimeDxe
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

The real variable driver has been updated to support emulated
variable NV mode.
This patch removes EmuVariableRuntimeDxe after platforms are
migrated to use the merged variable driver.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-02-19 17:36:11 +08:00
Dandan Bi 44289eeafd MdeModulePkg: Fix coding style issues
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1479

Fix issues that reported by Edk2 coding style check tool(ECC) that:
Comment description should end with period '.'

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2019-02-02 21:41:38 +08:00
Star Zeng 9084239f34 MdeModulePkg VariableStandaloneMm: Add PcdEmuVariableNvModeEnable in inf
It was missed in 7cd6995946 when rebasing
the patches after 688b2cad7b added
VariableStandaloneMm.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dandan Bi <dandan.bi@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
2019-01-25 11:41:14 +08:00
Star Zeng 3c007f3653 MdeModulePkg VariablePei: Don't check BOOT_IN_RECOVERY_MODE
Don't check BOOT_IN_RECOVERY_MODE, but check PcdEmuVariableNvModeEnable
which platform can configure flexibly.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:37 +08:00
Star Zeng 7cd6995946 MdeModulePkg Variable: Add emulated variable NV mode support
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Add emulated variable NV mode support in real variable driver.
Platform can configure PcdEmuVariableNvModeEnable statically
(build time) or dynamically (boot time) to support emulated
variable NV mode.

If PcdEmuVariableNvModeEnable is configured to dynamic, its
value should be set before Variable driver starts to work,
otherwise default value will take effect.

Then EmuVariableRuntimeDxe could be removed, the removal of
EmuVariableRuntimeDxe will be done after platforms are migrated
to use the merged variable driver.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:36 +08:00
Star Zeng 602cd0b6ba MdeModulePkg Variable: type case VolatileBase to UINTN directly
Simplify
((UINTN) ((UINT8 *) VolatileBase + VolatileBase->Size))
to
((UINTN) VolatileBase + VolatileBase->Size)

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:34 +08:00
Star Zeng ebe34c96f4 MdeModulePkg Variable: Remove CacheOffset in UpdateVariable()
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

CacheOffset could be removed in UpdateVariable() after
//
// update the memory copy of Flash region.
//
CopyMem (
  (UINT8 *)mNvVariableCache + CacheOffset,
  (UINT8 *)NextVariable, VarSize
   );

is moved to be before mVariableModuleGlobal->NonVolatileLastVariableOffset
value is updated, like right before
mVariableModuleGlobal->NonVolatileLastVariableOffset +=
  HEADER_ALIGN (VarSize);

Except for the movement above, the patch also capitalizes the first
character of "update the memory copy of Flash region".

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:33 +08:00
Star Zeng b59fd889ac MdeModulePkg Variable: Abstract VariableWriteServiceInitializeDxe/Smm
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Abstract VariableWriteServiceInitializeDxe/Smm from
FtwNotificationEvent/SmmFtwNotificationEvent, then
VariableWriteServiceInitializeDxe/Smm could be not aware
the NV storage is real or emulated.

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:32 +08:00
Star Zeng 904e0ca997 MdeModulePkg Variable: Not get NV PCD in VariableWriteServiceInitialize
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Add macro NV_STORAGE_VARIABLE_BASE.
Not get NV PCD in VariableWriteServiceInitialize, but in
FtwNotificationEvent/SmmFtwNotificationEvent, then
VariableWriteServiceInitialize could be not aware the NV
storage is real or emulated.

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:32 +08:00
Star Zeng 5f0871e3d8 MdeModulePkg Variable: Move "extern XXX" to Variable.h
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Move "extern XXX" to Variable.h from VariableDxe.c/VariableSmm.c.

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:31 +08:00
Star Zeng 701d603f32 MdeModulePkg Variable: Abstract InitRealNonVolatileVariableStore
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Abstract InitRealNonVolatileVariableStore from
InitNonVolatileVariableStore.

This patch prepares for adding emulated variable NV mode
support in VariableRuntimeDxe.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:30 +08:00
Star Zeng 874c8434d1 MdeModulePkg Variable: Add some missing changes for 9b18845
To improve performance 9b18845a4b
changed the code which read from physical MMIO address to read
from memory cache, but it missed some places that could be updated
the same away for performance optimization.

The patch updates these places as supplementary.

I found them when updating code for
https://bugzilla.tianocore.org/show_bug.cgi?id=1323
Merge EmuVariable and Real variable driver.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-01-24 10:52:29 +08:00
Ard Biesheuvel 688b2cad7b MdeModulePkg/VariableRuntimeDxe: implement standalone MM version
Reuse most of the existing code to implement a variable runtime
driver that will be able to execute in the context of standalone
MM.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2019-01-16 20:10:51 +01:00
Ard Biesheuvel a855f63e2f MdeModulePkg/VariableRuntimeDxe: factor out boot service accesses
In preparation of providing a standalone MM based variable runtime
driver, move the existing SMM driver to the new MM services table,
and factor out some pieces that are specific to the traditional
driver, mainly related to the use of UEFI boot services, which are
not accessible to standalone MM drivers.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2019-01-16 20:10:51 +01:00
Hao Wu 49395ea0bc MdeModulePkg/Variable: Update to consume SpeculationBarrier
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1417

Since BaseLib API AsmLfence() is a x86 arch specific API and should be
avoided using in generic codes, this commit replaces the usage of
AsmLfence() with arch-generic API SpeculationBarrier().

Please note that speculation execution barriers are intended to be
asserted for SMM codes, hence, this commit still preserve an empty
implementation of the speculation execution barrier for the DXE codes.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
2018-12-25 09:16:11 +08:00
Vijayenthiran Subramaniam a90c7df7ed MdeModulePkg/Variable: add debug logs in VariableServiceSetVariable
Print debug messages if size of the VariableName plus DataSize exceeds
Max(Auth|Voltaile)VariableSize bytes. The messages will be useful if any
platform specific value of Max(Auth|Voltaile)VariableSize PCDs have to
be changed.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-11-23 09:54:55 +08:00
Star Zeng b7dc8888f3 MdeModulePkg Variable: Fix Timestamp zeroing issue on APPEND_WRITE
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=415

When SetVariable() to a time based auth variable with APPEND_WRITE
attribute, and if the EFI_VARIABLE_AUTHENTICATION_2.TimeStamp in
the input Data is earlier than current value, it will cause timestamp
zeroing.

This issue may bring time based auth variable downgrade problem.
For example:
A vendor released three certs at 2014, 2015, and 2016, and system
integrated the 2016 cert. User can SetVariable() with 2015 cert and
APPEND_WRITE attribute to cause timestamp zeroing first, then
SetVariable() with 2014 cert to downgrade the cert.

This patch fixes this issue.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Chao Zhang <chao.b.zhang@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
2018-10-17 11:24:44 +08:00
Hao Wu e83d841fdc MdeModulePkg/Variable: [CVE-2017-5753] Fix bounds check bypass
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1194

Speculative execution is used by processor to avoid having to wait for
data to arrive from memory, or for previous operations to finish, the
processor may speculate as to what will be executed.

If the speculation is incorrect, the speculatively executed instructions
might leave hints such as which memory locations have been brought into
cache. Malicious actors can use the bounds check bypass method (code
gadgets with controlled external inputs) to infer data values that have
been used in speculative operations to reveal secrets which should not
otherwise be accessed.

This commit will focus on the SMI handler(s) registered within the
Variable\RuntimeDxe driver and insert AsmLfence API to mitigate the
bounds check bypass issue.

For SMI handler SmmVariableHandler():

Under "case SMM_VARIABLE_FUNCTION_GET_VARIABLE:",
'SmmVariableHeader->NameSize' can be a potential cross boundary access of
the 'CommBuffer' (controlled external input) during speculative execution.

This cross boundary access is later used as the index to access array
'SmmVariableHeader->Name' by code:
"SmmVariableHeader->Name[SmmVariableHeader->NameSize/sizeof (CHAR16) - 1]"
One can observe which part of the content within array was brought into
cache to possibly reveal the value of 'SmmVariableHeader->NameSize'.

Hence, this commit adds a AsmLfence() after the boundary/range checks of
'CommBuffer' to prevent the speculative execution.

And there are 2 similar cases under
"case SMM_VARIABLE_FUNCTION_SET_VARIABLE:" and
"case SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET:" as well.
This commits also handles them.

Also, under "case SMM_VARIABLE_FUNCTION_SET_VARIABLE:",
'(UINT8 *)SmmVariableHeader->Name + SmmVariableHeader->NameSize' points to
the 'CommBuffer' (with some offset) and then passed as parameter 'Data' to
function VariableServiceSetVariable().

Within function VariableServiceSetVariable(), there is a sanity check for
EFI_VARIABLE_AUTHENTICATION_2 descriptor for the data pointed by 'Data'.
If this check is speculatively bypassed, potential cross-boundary data
access for 'Data' is possible to be revealed via the below function calls
sequence during speculative execution:

AuthVariableLibProcessVariable()
ProcessVarWithPk() or ProcessVarWithKek()

Within function ProcessVarWithPk() or ProcessVarWithKek(), for the code
"PayloadSize = DataSize - AUTHINFO2_SIZE (Data);", 'AUTHINFO2_SIZE (Data)'
can be a cross boundary access during speculative execution.

Then, 'PayloadSize' is possible to be revealed by the function call
sequence:

AuthServiceInternalUpdateVariableWithTimeStamp()
mAuthVarLibContextIn->UpdateVariable()
VariableExLibUpdateVariable()
UpdateVariable()
CopyMem()

Hence, this commit adds a AsmLfence() after the sanity check for
EFI_VARIABLE_AUTHENTICATION_2 descriptor upon 'Data' within function
VariableServiceSetVariable() to prevent the speculative execution.

Also, please note that the change made within function
VariableServiceSetVariable() will affect DXE as well. However, since we
only focuses on the SMM codes, the commit will introduce a new module
internal function called VariableLoadFence() to handle this. This internal
function will have 2 implementations (1 for SMM, 1 for DXE). For the SMM
implementation, it is a wrapper to call the AsmLfence() API; for the DXE
implementation, it is empty.

A more detailed explanation of the purpose of commit is under the
'Bounds check bypass mitigation' section of the below link:
https://software.intel.com/security-software-guidance/insights/host-firmware-speculative-execution-side-channel-mitigation

And the document at:
https://software.intel.com/security-software-guidance/api-app/sites/default/files/337879-analyzing-potential-bounds-Check-bypass-vulnerabilities.pdf

Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2018-09-30 13:06:42 +08:00
Star Zeng 4063d37c6a MdeModulePkg Variable: Fix comment typo 'end' to 'start'
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1214
This patch only updates comment and function description, so has
no functionality impact.

This patch fixes comment typo 'end' to 'start' in GetStartPointer.

GetStartPointer for PEI and DXE has aligned function description,
but GetEndPointer does not.
This patch also aligns GetEndPointer's function description for
PEI and DXE.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-09-28 11:13:34 +08:00
Chen A Chen de005223b7 MdeModulePkg: Removing ipf which is no longer supported from edk2.
Removing rules for Ipf sources file:
* Remove the source file which path with "ipf" and also listed in
  [Sources.IPF] section of INF file.
* Remove the source file which listed in [Components.IPF] section
  of DSC file and not listed in any other [Components] section.
* Remove the embedded Ipf code for MDE_CPU_IPF.

Removing rules for Inf file:
* Remove IPF from VALID_ARCHITECTURES comments.
* Remove DXE_SAL_DRIVER from LIBRARY_CLASS in [Defines] section.
* Remove the INF which only listed in [Components.IPF] section in DSC.
* Remove statements from [BuildOptions] that provide IPF specific flags.
* Remove any IPF sepcific sections.

Removing rules for Dec file:
* Remove [Includes.IPF] section from Dec.

Removing rules for Dsc file:
* Remove IPF from SUPPORTED_ARCHITECTURES in [Defines] section of DSC.
* Remove any IPF specific sections.
* Remove statements from [BuildOptions] that provide IPF specific flags.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-09-06 15:25:16 +08:00
Zhang, Chao B 5da2c9b27a MdeModulePkg: Variable: Re-prioritize TCG/TCG2 protocol
TPM1.2 is obsoleted by TPM2.0. switch TCG/TCG2 protocol check to apply this
trend

Cc: Long, Qin <qin.long@intel.com>
Cc: Yao, Jiewen <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zhang, Chao B <chao.b.zhang@intel.com>
Reviewed-by: Yao, Jiewen <jiewen.yao@intel.com>
2018-07-23 08:36:03 +08:00
Brijesh Singh f88290964f MdeModulePkg/Variable: Check EFI_MEMORY_RUNTIME attribute before setting it
Set the EFI_MEMORY_RUNTIME attribute in FtwNotificationEvent() only if
the attribute is not already present. This will ensure that the attributes
set by the platform drivers (e.g Ovmf pflash) is not lost.

Cc: Dong Eric <eric.dong@intel.com>
Cc: Justen Jordan L <jordan.l.justen@intel.com>
Cc: Zeng Star <star.zeng@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Reviewed-by: Star Zeng <star.zeng@intel.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2018-07-04 22:21:00 +08:00
Star Zeng 5f46352300 MdeModulePkg Variable: Add/Correct GetHobVariableStore para description
It is caused by 09808bd39b.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
2018-07-03 14:44:08 +08:00
Star Zeng fdd3e77a42 MdeModulePkg Variable: Make sure no more than one Variable HOB
VariableHob may be built in PcdPeim (by PcdNvStoreDefaultValueBuffer)
or some platform module (by some tool).
The two solutions should not be co-exist.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2018-07-02 11:23:24 +08:00
Star Zeng 09808bd39b MdeModulePkg Variable: Abstract GetHobVariableStore function
Move getting HOB variable store code logic to a separated
GetHobVariableStore function.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2018-07-02 11:23:23 +08:00
Liming Gao d1102dba72 MdeModulePkg: Clean up source files
1. Do not use tab characters
2. No trailing white space in one line
3. All files must end with CRLF

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-06-28 11:19:45 +08:00
Liming Gao 051bf6e0af MdeModulePkg Variable: Use comparison logic to check UINTN parameter
Commit 180ac200da changes the input parameter
from BOOLEAN to UINTN. Its comparison logic should be updated.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-06-12 09:23:14 +08:00
Liming Gao 180ac200da MdeModulePkg Variable: Fix XCODE5 varargs warning
https://bugzilla.tianocore.org/show_bug.cgi?id=741
Change VariableGetBestLanguage() parameter type from BOOLEAN to UINTN

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Steven Shi <steven.shi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2018-05-23 10:37:49 +08:00
cinnamon shia 989f7a2cf0 MdeModulePkg Variable: Fix the returned status in UpdateVariableStore
If Fvb is a NULL, return EFI_UNSUPPORTED.
If the remaining size is not enough, return EFI_OUT_OF_RESOURCES.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: cinnamon shia <cinnamon.shia@hpe.com>
Signed-off-by: Ansen Huang <ansen.huang@hpe.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-05-14 10:04:55 +08:00
cinnamon shia d741d14193 MdeModulePkg Variable: Fix a corner case issue about setting a variable
Fix the issue that failed to update or add a UEFI variable if the remaining size is equal to the data size
of the variable.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: cinnamon shia <cinnamon.shia@hpe.com>
Signed-off-by: Ansen Huang <ansen.huang@hpe.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-05-14 10:04:50 +08:00
Laszlo Ersek 9b4a20321e MdeModulePkg/Variable/RuntimeDxe: introduce PcdMaxVolatileVariableSize
The variable driver doesn't distinguish "non-volatile non-authenticated"
variables from "volatile non-authenticated" variables, when checking
individual variable sizes against the permitted maximum.
PcdMaxVariableSize covers both kinds.

This prevents volatile non-authenticated variables from carrying large
data between UEFI drivers, despite having no flash impact. One example is
EFI_TLS_CA_CERTIFICATE_VARIABLE, which platforms might want to create as
volatile on every boot: the certificate list can be several hundred KB in
size.

Introduce PcdMaxVolatileVariableSize to represent the limit on individual
volatile non-authenticated variables. The default value is zero, which
makes Variable/RuntimeDxe fall back to PcdMaxVariableSize (i.e. the
current behavior). This is similar to the PcdMaxAuthVariableSize fallback.

Whenever the size limit is enforced, consult MaxVolatileVariableSize as
the last option, after checking
- MaxAuthVariableSize for VARIABLE_ATTRIBUTE_AT_AW,
- and MaxVariableSize for EFI_VARIABLE_NON_VOLATILE.

EFI_VARIABLE_HARDWARE_ERROR_RECORD is always handled separately; it always
takes priority over the three cases listed above.

Introduce the GetMaxVariableSize() helper to consider
PcdMaxVolatileVariableSize, in addition to
GetNonVolatileMaxVariableSize(). GetNonVolatileMaxVariableSize() is
currently called at three sites, and two of those need to start using
GetMaxVariableSize() instead:
- VariableServiceInitialize() [VariableSmm.c]: the SMM comms buffer must
  accommodate all kinds of variables,
- VariableCommonInitialize() [Variable.c]: the preallocated scratch space
  must also accommodate all kinds of variables,
- InitNonVolatileVariableStore() [Variable.c] can continue using
  GetNonVolatileMaxVariableSize().

Don't modify the ReclaimForOS() function as it is specific to non-volatile
variables and should ignore PcdMaxVolatileVariableSize.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Gary Lin <glin@suse.com>
Tested-by: Gary Lin <glin@suse.com>
[lersek@redhat.com: set MaxVolatileVariableSize where Star suggested]
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-03-30 21:17:07 +02:00
Star Zeng 3d7ebd6434 MdeModulePkg Variable: Align TPL level for (Smm)EndOfDxe callback
VariableRuntimeDxe will have OnEndOfDxe() callback function at
TPL_NOTIFY level on EndOfDxe event when DXE variable solution is
used.
  Status = gBS->CreateEventEx (
                  EVT_NOTIFY_SIGNAL,
                  TPL_NOTIFY,
                  OnEndOfDxe,
                  NULL,
                  &gEfiEndOfDxeEventGroupGuid,
                  &EndOfDxeEvent
                  );

VariableSmm will have SmmEndOfDxeCallback() callback function at
TPL_CALLBACK level on SmmEndOfDxe event when SMM variable solution
is used.
SmmIplGuidedEventNotify()  -  PiSmmIpl.c TPL_CALLBACK on EndOfDxe
->
SmmEndOfDxeHandler()  -  PiSmmCore.c install SmmEndOfDxe protocol
->
SmmEndOfDxeCallback() - VariableSmm.c

The TPL level for (Smm)EndOfDxe callback between VariableRuntimeDxe
and VariableSmm is inconsistent, it will make the unified platform
code could not make sure its TPL_NOTIFY EndOfDxe callback function
(to use variable lock/check) executed before (Smm)EndOfDxe callback
function in variable driver. The variable lock/check will start to
protect after (Smm)EndOfDxe callback function in variable driver is
executed.

This patch is to algin the TPL level to TPL_CALLBACK for (Smm)EndOfDxe
callback between VariableRuntimeDxe and VariableSmm.

Cc: Chasel Chiu <chasel.chiu@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Chasel Chiu <chasel.chiu@intel.com>
2018-03-30 14:14:25 +08:00
Liming Gao 56d0bd7eb8 MdeModulePkg Variable: Use boolean type value instead of expression
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2017-12-27 17:40:41 +08:00
Liming Gao 1b79547a91 MdeModulePkg Variable: Update Pointer Minus with UINTN type
In V2, reduce unnecessary () in the expression.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2017-12-26 17:46:30 +08:00
Liming Gao a37044efba MdeModulePkg VariableDxe: Update it supports normal format variable storage
PEI may report the normal format variable storage HOB for the default
EFI variable. VariableDxe needs to support it and set them into NV variable
region.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2017-12-25 11:05:55 +08:00
chenc2 67943427ad MdeModulePkg/Variable/RuntimeDxe: Modify function return status
Make VariableServiceSetVariable and VariableServiceQueryVariableInfo
functions return status following UEFI 2.7 spec.

Cc: Zhang Chao <chao.b.zhang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: chenc2 <chen.a.chen@intel.com>
Reviewed-by: Chao Zhang <chao.b.zhang@intel.com>
2017-12-15 21:56:33 +08:00
Zenith432 a0460be7e8 MdeModulePkg: loose VA_COPY with no matching VA_END on a return path
In CheckRemainingSpaceForConsistencyInternal, one of the return paths leaves a loose
VA_COPY with no matching VA_END.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zenith432 <zenith432@users.sourceforge.net>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2017-12-11 09:07:40 +08:00
Zhang, Chao B 4073f85d4a MdeModulePkg: Deprecate EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
Mark EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS as deprecated.
1. Make SetVariable/QueryVariableInfo return EFI_UNSUPPORTED with this
   attribute
2. No change to GetVariable/GetNextVariableName
Also update several function descriptors accordingly

Cc: Long Qin <qin.long@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Chao Zhang <chao.b.zhang@intel.com>
Reviewed-by: Long Qin <qin.long@intel.com>
2017-11-01 22:25:36 +08:00
Laszlo Ersek 704b71d7e1 MdeModulePkg/Variable/RuntimeDxe: delete & lock MOR in the absence of SMM
VariableRuntimeDxe deletes and locks the MorLock variable in
MorLockInit(), with the argument that any protection provided by MorLock
can be circumvented if MorLock can be overwritten by unprivileged code
(i.e., outside of SMM).

Extend the argument and the logic to the MOR variable, which is supposed
to be protected by MorLock. Pass Attributes=0 when deleting MorLock and
MOR both.

This change was suggested by Star; it is inspired by earlier VariableSmm
commit fda8f631ed ("MdeModulePkg/Variable/RuntimeDxe: delete and lock
OS-created MOR variable", 2017-10-03).

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Suggested-by: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2017-10-25 14:06:15 +02:00
Laszlo Ersek fda8f631ed MdeModulePkg/Variable/RuntimeDxe: delete and lock OS-created MOR variable
According to the TCG Platform Reset Attack Mitigation Specification (May
15, 2008):

> 5 Interface for UEFI
> 5.1 UEFI Variable
> 5.1.1 The MemoryOverwriteRequestControl
>
> Start of informative comment:
>
> [...] The OS loader should not create the variable. Rather, the firmware
> is required to create it and must support the semantics described here.
>
> End of informative comment.

However, some OS kernels create the MOR variable even if the platform
firmware does not support it (see one Bugzilla reference below). This OS
issue breaks the logic added in the last patch.

Strengthen the MOR check by searching for the TCG or TCG2 protocols, as
edk2's implementation of MOR depends on (one of) those protocols.

The protocols are defined under MdePkg, thus there's no inter-package
dependency issue. In addition, calling UEFI services in
MorLockInitAtEndOfDxe() is safe, due to the following order of events /
actions:

- platform BDS signals the EndOfDxe event group,
- the SMM core installs the SmmEndOfDxe protocol,
- MorLockInitAtEndOfDxe() is invoked, and it calls UEFI services,
- some time later, platform BDS installs the DxeSmmReadyToLock protocol,
- SMM / SMRAM is locked down and UEFI services become unavailable to SMM
  drivers.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1498159
Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:28 +02:00
Laszlo Ersek 7516532f9c MdeModulePkg/Variable/RuntimeDxe: delay MorLock creation until EndOfDxe
The "MemoryOverwriteRequestControl" (a.k.a. MOR) variable comes from the
"TCG Platform Reset Attack Mitigation Specification":

https://www.trustedcomputinggroup.org/wp-content/uploads/Platform-Reset-Attack-Mitigation-Specification.pdf

The "MemoryOverwriteRequestControlLock" variable (a.k.a. MORL) is a
Microsoft extension, called "Secure MOR implementation":

https://docs.microsoft.com/en-us/windows-hardware/drivers/bringup/device-guard-requirements

Currently the VariableSmm driver creates MORL without regard to MOR. This
can lead to a situation where a platform does not support MOR from the
prerequisite spec (because it does not include the
"SecurityPkg/Tcg/MemoryOverwriteControl/TcgMor.inf" driver), but appears
to support MORL from the dependent Microsoft spec.

"winload.efi" notices this inconsistency, and disables the Device Guard
Virtualization Based Security in Windows Server 2016 and Windows 10 64-bit
Enterprise.

If the platform includes
"SecurityPkg/Tcg/MemoryOverwriteControl/TcgMor.inf", then MOR will exist
by the time EndOfDxe is reached, and VariableSmm can safely create MORL.
Otherwise, do not create MORL (delete it if it exists), and also prevent
other modules from creating it.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=727
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1496170
Reported-by: Ladi Prosek <lprosek@redhat.com>
Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:26 +02:00
Laszlo Ersek e3531164cc MdeModulePkg/Variable/RuntimeDxe: permit MorLock deletion for passthru req
The SetMorLockVariable() function sets "mMorLockPassThru" to TRUE
temporarily, so that it can set the MOR Control Lock variable to
well-formed values without permission checks.

In the next patch, we'll need the same override for deleting the MOR
Control Lock variable; hence obey "mMorLockPassThru" in the deletion
branch of SetVariableCheckHandlerMorLock() as well.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:23 +02:00
Laszlo Ersek f130428043 MdeModulePkg/Variable/RuntimeDxe: introduce MorLockInitAtEndOfDxe() hook
Introduce the MorLockInitAtEndOfDxe() hook, in order to allow
MorLockInit() to delay / queue operations until EndOfDxe. (Or, if the
platform never signals EndOfDxe, until ReadyToBoot.)

Call MorLockInitAtEndOfDxe() whenever we set "mEndOfDxe" to TRUE:

- in VariableRuntimeDxe:
  - in the OnReadyToBoot() function,
  - in the OnEndOfDxe() function;

- in VariableSmm:
  - on the SMM_VARIABLE_FUNCTION_READY_TO_BOOT SMI request,
  - in the SmmEndOfDxeCallback() function.

For now, implement MorLockInitAtEndOfDxe() as a no-op in both
VariableRuntimeDxe and VariableSmm.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:21 +02:00
Laszlo Ersek 03877377e3 MdeModulePkg/Variable/RuntimeDxe: move MOR func. declarations to header
The MorLockInit() and SetVariableCheckHandlerMor() functions have separate
implementations for VariableRuntimeDxe (= unprivileged, unified
DXE_RUNTIME driver) and VariableSmm (= privileged, DXE_SMM back-end of the
split variable driver).

Move their declarations from "Variable.c" to "PrivilegePolymorphic.h", so
that the compiler enforce that the declarations and the definitions match.
(All C source files with the call sites and the function definitions
already include "PrivilegePolymorphic.h" via "Variable.h".)

At the same time:

- replace two typos in the MorLockInit() description:
  - replace "EFI_SUCEESS" with "EFI_SUCCESS",
  - replace "MOR Lock Control" with "MOR Control Lock";

- in the SetVariableCheckHandlerMor() description:
  - replace @param with @param[in],
  - correct the description of the Attributes parameter (suggested by Star
    Zeng <star.zeng@intel.com>),
  - rewrap the comment to 80 columns.

This change cleans up commit 2f6aa774fe ("MdeModulePkg: Add MorLock to
variable driver.", 2016-01-19).

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:19 +02:00
Laszlo Ersek 00663d047f MdeModulePkg/Variable/RuntimeDxe: move SecureBootHook() decl to new header
If the platform supports SMM, a gRT->SetVariable() call at boot time
results in the following call tree to SecureBootHook():

  RuntimeServiceSetVariable()      [VariableSmmRuntimeDxe.c, unprivileged]
    SmmVariableHandler()           [VariableSmm.c,             PRIVILEGED]
      VariableServiceSetVariable() [Variable.c,                PRIVILEGED]
        SecureBootHook()           [VariableSmm.c,             PRIVILEGED]
          //
          // do nothing
          //
    SecureBootHook()               [Measurement.c,           unprivileged]
      //
      // measure variable if it
      // is related to SB policy
      //

And if the platform does not support SMM:

  VariableServiceSetVariable()     [Variable.c,              unprivileged]
    SecureBootHook()               [Measurement.c,           unprivileged]
      //
      // measure variable if it
      // is related to SB policy
      //

In other words, the measurement always happens outside of SMM.

Because there are two implementations of the SecureBootHook() API, one
that is called from SMM and does nothing, and another that is called
outside of SMM and measures variables, the function declaration should be
in a header file. This way the compiler can enforce that the function
declaration and all function definitions match.

"Variable.h" is used for "including common header files, defining internal
structures and functions used by Variable modules". Technically, we could
declare SecureBootHook() in "Variable.h". However, "Measurement.c" and
"VariableSmmRuntimeDxe.c" themselves do not include "Variable.h", and that
is likely intentional -- "Variable.h" exposes so much of the privileged
variable implementation that it is likely excluded from these C source
files on purpose.

Therefore introduce a new header file called "PrivilegePolymorphic.h".
"Variable.h" includes this header (so that all C source files that have
been allowed to see the variable internals learn about the new
SecureBootHook() declaration immediately). In "Measurement.c" and
"VariableSmmRuntimeDxe.c", include *only* the new header.

This change cleans up commit fa0737a839 ("MdeModulePkg Variable: Merge
from Auth Variable driver in SecurityPkg", 2015-07-01).

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
2017-10-10 11:25:04 +02:00
Zhang, Chao B 7ef0dae092 MdeModulePkg: Variable: Fix typo in variable measure
Fix variable measure debug message typo.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Yao Jiewen <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Chao Zhang <chao.b.zhang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2017-08-09 22:42:29 +08:00
Star Zeng 6f817f9b8b MdeModulePkg Variable: Update GetNextVariableName to follow UEFI 2.7
"The size must be large enough to fit input string supplied in
VariableName buffer" is added in the description for VariableNameSize.
And two cases of EFI_INVALID_PARAMETER are added.
1. The input values of VariableName and VendorGuid are not a name and
   GUID of an existing variable.
2. Null-terminator is not found in the first VariableNameSize bytes of
   the input VariableName buffer.

This patch is to update code to follow them.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2017-06-27 13:57:39 +08:00
Star Zeng 746645bdef MdeModulePkg Variable: Add missing change in dd59d95e19
dd59d95e19 updated *.c file, but forgot to update *.h file.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2017-06-22 17:56:13 +08:00
Star Zeng 9977995e68 MdeModulePkg: Minor update to the Data parameter for PEI GetVariable()
PI 1.5 spec has minor update to the Data parameter for PEI
GetVariable(), and no real functional behavior change.

The modifier of Data parameter:
OUT VOID *Data
->
OUT VOID *Data OPTIONAL

The comments of Data parameter:
Data    Points to the buffer which will hold the returned variable value.
->
Data    Points to the buffer which will hold the returned variable value.
        May be NULL with a zero DataSize in order to determine the size of the buffer needed.

The patch is to follow the spec to update the implementation.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2017-06-22 17:56:12 +08:00
Hao Wu 16f6922709 MdeModulePkg: Refine casting expression result to bigger size
There are cases that the operands of an expression are all with rank less
than UINT64/INT64 and the result of the expression is explicitly cast to
UINT64/INT64 to fit the target size.

An example will be:
UINT32 a,b;
// a and b can be any unsigned int type with rank less than UINT64, like
// UINT8, UINT16, etc.
UINT64 c;
c = (UINT64) (a + b);

Some static code checkers may warn that the expression result might
overflow within the rank of "int" (integer promotions) and the result is
then cast to a bigger size.

The commit refines codes by the following rules:
1). When the expression is possible to overflow the range of unsigned int/
int:
c = (UINT64)a + b;

2). When the expression will not overflow within the rank of "int", remove
the explicit type casts:
c = a + b;

3). When the expression will be cast to pointer of possible greater size:
UINT32 a,b;
VOID *c;
c = (VOID *)(UINTN)(a + b); --> c = (VOID *)((UINTN)a + b);

4). When one side of a comparison expression contains only operands with
rank less than UINT32:
UINT8 a;
UINT16 b;
UINTN c;
if ((UINTN)(a + b) > c) {...} --> if (((UINT32)a + b) > c) {...}

For rule 4), if we remove the 'UINTN' type cast like:
if (a + b > c) {...}
The VS compiler will complain with warning C4018 (signed/unsigned
mismatch, level 3 warning) due to promoting 'a + b' to type 'int'.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
2017-03-06 14:33:20 +08:00