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| author | Jian J Wang <jian.j.wang@intel.com> | 2018-10-17 12:49:57 +0800 |
|---|---|---|
| committer | Jian J Wang <jian.j.wang@intel.com> | 2018-10-18 13:19:14 +0800 |
| commit | eae7b476c2151141a43cc89d9629c47757f024f1 (patch) | |
| tree | d54bdadbfb298f8360ddf45e1fc5ff7f347fda22 /UefiCpuPkg | |
| parent | fea5e28658c672ce2cbe38d0927ab27beb792097 (diff) | |
| download | edk2-eae7b476c2151141a43cc89d9629c47757f024f1.zip edk2-eae7b476c2151141a43cc89d9629c47757f024f1.tar.gz edk2-eae7b476c2151141a43cc89d9629c47757f024f1.tar.bz2 | |
UefiCpuPkg/CpuExceptionHandlerLib: always clear descriptor data in advance
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1237
Sometimes the memory will be contaminated by random data left in last
boot (warm reset). The code should not assume the allocated memory is
always filled with zero. This patch add code to clear data structure
used for stack switch to prevent such problem from happening.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Diffstat (limited to 'UefiCpuPkg')
| -rw-r--r-- | UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c | 3 | ||||
| -rw-r--r-- | UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c | 3 |
2 files changed, 6 insertions, 0 deletions
diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c index 031d0d3..4a61b61 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c @@ -214,6 +214,7 @@ ArchSetupExcpetionStack ( //
TssBase = (UINTN)Tss;
+ TssDesc->Uint64 = 0;
TssDesc->Bits.LimitLow = sizeof(IA32_TASK_STATE_SEGMENT) - 1;
TssDesc->Bits.BaseLow = (UINT16)TssBase;
TssDesc->Bits.BaseMid = (UINT8)(TssBase >> 16);
@@ -238,6 +239,7 @@ ArchSetupExcpetionStack ( //
TssBase = (UINTN)Tss;
+ TssDesc->Uint64 = 0;
TssDesc->Bits.LimitLow = sizeof(IA32_TASK_STATE_SEGMENT) - 1;
TssDesc->Bits.BaseLow = (UINT16)TssBase;
TssDesc->Bits.BaseMid = (UINT8)(TssBase >> 16);
@@ -255,6 +257,7 @@ ArchSetupExcpetionStack ( continue;
}
+ ZeroMem (Tss, sizeof (*Tss));
Tss->EIP = (UINT32)(TemplateMap.ExceptionStart
+ Vector * TemplateMap.ExceptionStubHeaderSize);
Tss->EFLAGS = 0x2;
diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c index 93ecf5a..5dc6281 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c @@ -219,6 +219,8 @@ ArchSetupExcpetionStack ( //
TssBase = (UINTN)Tss;
+ TssDesc->Uint128.Uint64 = 0;
+ TssDesc->Uint128.Uint64_1= 0;
TssDesc->Bits.LimitLow = sizeof(IA32_TASK_STATE_SEGMENT) - 1;
TssDesc->Bits.BaseLow = (UINT16)TssBase;
TssDesc->Bits.BaseMidl = (UINT8)(TssBase >> 16);
@@ -231,6 +233,7 @@ ArchSetupExcpetionStack ( //
// Fixup exception task descriptor and task-state segment
//
+ ZeroMem (Tss, sizeof (*Tss));
StackTop = StackSwitchData->X64.KnownGoodStackTop - CPU_STACK_ALIGNMENT;
StackTop = (UINTN)ALIGN_POINTER (StackTop, CPU_STACK_ALIGNMENT);
IdtTable = StackSwitchData->X64.IdtTable;
|