1. increment build not skip make file when not change any file
2. report file generate abundant blank line
3. Build encounter Database is locked on some platform, using database
auto commit
4. Fv BaseAddress must have if set
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
PEP 238 -- Changing the Division Operator
x/y to return a reasonable approximation of the mathematical result
of the division ("true division")
x//y to return the floor ("floor division")
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Because the long() function was not exist in Python3.
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Updated Redistributor base calculation to allow for the fact that
GICv4 has 2 additional 64KB frames (for VLPI and a reserved frame).
The code now tests the VLPIS bit in the GIC Redistributor Type
Register (GICR_TYPER) and calculates the Redistributor granularity
accordingly.
The code changes are:
GICR_TYPER register fields, etc, added to the header.
Loop updated to pay attention to GICR_TYPER.Last.
Derive frame "stride" size from GICR_TYPER.VLPIS.
Note: The assumption is that the redistributors are adjacent for
all CPUs. However this may not be the case for NUMA systems.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Clock control is similar in SDHCI versions greater then version 2. Add
support for more recent versions of the controller specification.
SD card support for 1.8V is also present in controller versions 3 and
greater.
https://bugzilla.tianocore.org/show_bug.cgi?id=1233
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Add SDHCI controller defines, this is useful as the version in the
register does not explictly map to a specification version. For example
vesion 4.10 of the specification is version 0x04.
https://bugzilla.tianocore.org/show_bug.cgi?id=1233
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1229
When converting DebugPort device path from text,
current code use VENDOR_DEFINED_MESSAGING_DEVICE_PATH structure
for Debug port device node.
typedef struct {
EFI_DEVICE_PATH_PROTOCOL Header;
EFI_GUID Guid;
UINT8 VendorDefinedData[1];
} VENDOR_DEFINED_MESSAGING_DEVICE_PATH;
And Debugport Device Path is a vendor-defined messaging
device path with no data, only a GUID. So it's better to
use VENDOR_DEVICE_PATH to create the Debug port device node.
typedef struct {
EFI_DEVICE_PATH_PROTOCOL Header;
EFI_GUID Guid;
} VENDOR_DEVICE_PATH;
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
ShellPkg-Cd: Ensure all valid cd targets are handled properly
Make sure that PathCleanUpDirectories() is called on all valid targets
of the cd command.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jim Dailey <jim_dailey@dell.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
MdePkg-BaseLib: Fix PathCleanUpDirectories() error involving "\..\.."
The loop that removes "xxxx\..\" errs when multiple "\.." sequences are
in the path. Before this change the code would modify a path like
"FS0:\efi\tools\..\.." to "FS0:\efi\\.." and then to "FS0:\efi\", but
the correct path is "FS0:\".
You can test the effect of this change in the shell by setting the
current directory to something like FS0:\efi\boot and then executing
the command "ls ..\..". Before the change you will see the files in
the FS0:\efi directory; after the change, you will see the files in
the root directory of FS0:.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jim Dailey <jim_dailey@dell.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
There are three warnings reported by GCC 4.8 and the later GCC release
are workaround with them.
And all the three warnings are invalid,so I just disable warnings rather
than fix them at now.
Following is the analysis from Laszlo Ersek.
(1)
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regcomp.c: In
> function 'compile_length_tree':
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regcomp.c:1516:7:
> warning: 'len' may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> int len;
> ^
I think this is an invalid warning; the type of the controlling expression
(node->type) is enum GimmickType, and the case labels cover all values of
the enum. An assert(0) could be added, I guess, but again, upstream
Oniguruma would be justified to reject the idea.
(2)
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regparse.c: In
> function 'parse_callout_args.isra.10.constprop.30':
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regparse.c:6753:25:
> warning: 'rl' may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> vals[n].l = rl;
> ^
This warning is invalid, given:
6749 if (cn > 0) {
6750 long rl;
6751 r = parse_long(enc, buf, bufend, 1, LONG_MAX, &rl);
6752 if (r == ONIG_NORMAL) {
6753 vals[n].l = rl;
Because parse_long() only returns ONIG_NORMAL after it sets (*rl).
(3)
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regparse.c: In
> function 'parse_callout_of_name.constprop.29':
> MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma/regparse.c:6861:38:
> warning: 'tag_end' may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> if (! is_allowed_callout_tag_name(enc, tag_start, tag_end))
This warning is also invalid, given:
6852 if (c == '[') {
6853 if (PEND) return ONIGERR_END_PATTERN_IN_GROUP;
6854 tag_start = p;
6855 while (! PEND) {
6856 if (PEND) return ONIGERR_END_PATTERN_IN_GROUP;
6857 tag_end = p;
6858 PFETCH_S(c);
6859 if (c == ']') break;
6860 }
6861 if (! is_allowed_callout_tag_name(enc, tag_start, tag_end))
6862 return ONIGERR_INVALID_CALLOUT_TAG_NAME;
6863
To see that, first we should note:
#define PEND (p < end ? 0 : 1)
therefore PEND doesn't change if neither "p" nor "end" change.
Second, when we reach line 6855 (the "while") for the very first time,
(!PEND) is certainly true (i.e., PEND is false), because otherwise we
would have bailed at line 6853. Therefore we reach line 6857, and assign
"tag_end". Regardless of whether we iterate zero or more *additional*
times around the loop, "tag_end" will have been set, whenever we reach
line 6861.
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Dongao Guo <dongao.guo@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1231
Build system already support override PCD value by command
line so add this support to GenCfgOpt.py
Also update revision to 0.53
Test: Verified UPD header files generated can reflect different
PCD values from --pcd build command input
Cc: Jiewen Yao <Jiewen.yao@intel.com>
Cc: Gao Liming <liming.gao@intel.com>
Cc: Zhu Yonghong <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chasel Chiu <chasel.chiu@intel.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
Reviewed-by: Zhu Yonghong <yonghong.zhu@intel.com>
Currently, the implementation of EFI_PCI_IO_PROTOCOL::GetLocation()
in NonDiscoverablePciDeviceDxe returns the same set of dummy values
for each instance of the NON_DISCOVERABLE_DEVICE protocol that it
attaches itself to. However, this turns out to be causing problems
in cases where software (such as the ARM Compliance Test Suite [ACS])
attempts to use these values to uniquely identify controllers, since
the collisions create ambiguity in this regard.
So let's modify GetLocation() to return an arbitrary bus/device tuple
on segment 0xff instead. This is guaranteed not to clash with other
non-discoverable PCI devices, and highly unlikely to clash with real
PCIe devices.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Marcin Wojtas <mw@semihalf.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1228
According to UEFI spec,for ACPI Expanded Device Path
when HID=PNP0A03 or CID=PNP0A03 and HID != PNP0A08,
the device path node can be displayed as: PciRoot(UID|UIDSTR)
When HID=PNP0A08 or CID=PNP0A08, the device path node can be
displayed as: PcieRoot(UID|UIDSTR). But current code miss the
code logic.
This commit is to do the enhancement.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1226
According to UEFI Spec, for ACPI Expanded Device Path,
when HIDSTR=empty, CIDSTR=empty, UID STR!=empty,
the ACPI Expanded Device Path node can be displayed as
AcpiExp(HID,CID,UIDSTR) format.
And if UID is 0 and UIDSTR is empty, then use AcpiEx format.
This patch is to correct the condition check to follow UEFI
Spec when convert the device path node to the AcpiExp text
format.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1227
According to UEFI Spec, ACPI Expanded Device Path can be display
AcpiEx(HID|HIDSTR,(CID|CIDSTR,UID|UIDSTR)), but current code display
UID|UIDSTR before CID|CIDSTR.
This patch is to fix this issue.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1225
According to UEFI spec, the string expression of UTF8 vendor
device node should be displayed as: VenUtf8(). Current code
display it as: VenUft8() by mistake when convert device
path node to text.
This commit is to fix this bug.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1224
When covert IFR binary to EFI_IFR_CHECKBOX structure,
Current code has following incorrect code logic:
IfrCheckBox = (EFI_IFR_CHECKBOX *) (IfrOpHdr + 1);
The correct one should be:
IfrCheckBox = (EFI_IFR_CHECKBOX *) IfrOpHdr;
1. The bug is in function "UpdateDefaultSettingInFormPackage()"
which is to update the default setting of some HII Questions
in the IFR binary data. So it only has impact when platform
overrides default setting in HII VarStore through DynamicHii
PCD setting in Platform DSC file. If platform doesn't
override default setting, it has no impact.
2. The implementation updates the "Flags" filed in the
EFI_IFR_CHECKBOX structure to update the default
setting of checkbox.
If using "IfrCheckBox = (EFI_IFR_CHECKBOX *) (IfrOpHdr + 1);"
when wants to update the " Flags" filed in checkbox,
but in fact it will update the opcode binary
data(opcode binary length) behind checkbox binary.
And then it will cause Browser can't parse the IFR
binary data correctly. And then the possible symptom
is that some HII Question and forms may be not parsed
and then cannot be shown.
This patch is to fix this bug.
Cc: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@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>
This is for conformance with the TCG "Platform Reset Attack Mitigation
Specification". Because clearing the CPU caches at boot doesn't impact
performance significantly, do it unconditionally, for simplicity's
sake.
Flush the cache on all logical processors, thanks to
EFI_PEI_MP_SERVICES_PPI and CacheMaintenanceLib.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Julien Grall <julien.grall@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
[lersek@redhat.com: remove bogus Message-Id line from commit msg]
Create a homefilesystem environment variable whose value is the file
system on which the executing shell is located. For example: "FS14:".
This eliminates the need for people to have to try and find the "boot"
file system in their startup script. After this change they can simply
execute %homefilesystem% to set the cwd to the root of the file system
where the shell is located.
A future enhancement could be to add "homefilesystem" to the list of
predefined, read-only variables listed in the EfiShellSetEnv function of
file ShellProtocol.c
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jim Dailey <jim_dailey@dell.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
refactor the error handling for the PCD value that is negative or it
exceed the max value.
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zhiju.Fan <zhijux.fan@intel.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>
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.
It is possible for SMI handler(s) to call EFI_SMM_CPU_PROTOCOL service
ReadSaveState() and use the content in the 'CommBuffer' (controlled
external inputs) as the 'CpuIndex'. So this commit will insert AsmLfence
API to mitigate the bounds check bypass issue within SmmReadSaveState().
For SmmReadSaveState():
The 'CpuIndex' will be passed into function ReadSaveStateRegister(). And
then in to ReadSaveStateRegisterByIndex().
With the call:
ReadSaveStateRegisterByIndex (
CpuIndex,
SMM_SAVE_STATE_REGISTER_IOMISC_INDEX,
sizeof(IoMisc.Uint32),
&IoMisc.Uint32
);
The 'IoMisc' can be a cross boundary access during speculative execution.
Later, 'IoMisc' is used as the index to access buffers 'mSmmCpuIoWidth'
and 'mSmmCpuIoType'. One can observe which part of the content within
those buffers was brought into cache to possibly reveal the value of
'IoMisc'.
Hence, this commit adds a AsmLfence() after the check of 'CpuIndex'
within function SmmReadSaveState() to prevent the speculative execution.
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: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
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>
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
SmmLockBox driver and insert AsmLfence API to mitigate the
bounds check bypass issue.
For SMI handler SmmLockBoxHandler():
Under "case EFI_SMM_LOCK_BOX_COMMAND_SAVE:", the 'CommBuffer' (controlled
external inputs) is passed to function SmmLockBoxSave().
'TempLockBoxParameterSave.Length' can be a potential cross boundary access
of the 'CommBuffer' during speculative execution. This cross boundary
access is later passed as parameter 'Length' into function SaveLockBox().
Within function SaveLockBox(), the value of 'Length' can be inferred by
code:
"CopyMem ((VOID *)(UINTN)SmramBuffer, (VOID *)(UINTN)Buffer, Length);".
One can observe which part of the content within 'Buffer' was brought into
cache to possibly reveal the value of 'Length'.
Hence, this commit adds a AsmLfence() after the boundary/range checks of
'CommBuffer' to prevent the speculative execution.
And there is a similar case under "case EFI_SMM_LOCK_BOX_COMMAND_UPDATE:"
function SmmLockBoxUpdate() as well. This commits also handles it.
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
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@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>
Yonghong Zhu
Yunhua Feng
Sami Mujawar
Jeff Brasen
Dandan Bi
Jim.Dailey@dell.com
Guo, Dongao
Chasel, Chiu
Ard Biesheuvel
Liming Gao
Jiaxin Wu
Marc-André Lureau
zhijufan
Hao Wu