From f4a25e813f7ffa624b4868eb19fe13a34c4778ce Mon Sep 17 00:00:00 2001 From: vanjeff Date: Thu, 16 Aug 2012 04:36:24 +0000 Subject: Add validation on ACPI_S3_CONTEXT.S3DebugBufferAddress, moreover only debug tip could override IDT entry for INT3. Signed-off-by: Jeff Fan Reviewed-by: Liming Gao git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13640 6f19259b-4bc3-4df7-8a09-765794883524 --- .../Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c | 29 +++++++++++----------- 1 file changed, 15 insertions(+), 14 deletions(-) (limited to 'MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c') diff --git a/MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c b/MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c index 8c34993587..40c27e4f67 100644 --- a/MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c +++ b/MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c @@ -126,23 +126,24 @@ SetIdtEntry ( // SetupCpuExceptionHandlers (); - // - // Update IDT entry INT3 - // - IdtEntry = (INTERRUPT_GATE_DESCRIPTOR *)(IdtDescriptor->Base + (3 * sizeof (INTERRUPT_GATE_DESCRIPTOR))); - S3DebugBuffer = (UINTN) (AcpiS3Context->S3DebugBufferAddress); - - IdtEntry->Offset15To0 = (UINT16)S3DebugBuffer; - IdtEntry->SegmentSelector = (UINT16)AsmReadCs (); - IdtEntry->Attributes = (UINT16)INTERRUPT_GATE_ATTRIBUTE; - IdtEntry->Offset31To16 = (UINT16)(S3DebugBuffer >> 16); - IdtEntry->Offset63To32 = (UINT32)(S3DebugBuffer >> 32); - IdtEntry->Reserved = 0; + DEBUG_CODE ( + // + // Update IDT entry INT3 if the instruction is valid in it + // + S3DebugBuffer = (UINTN) (AcpiS3Context->S3DebugBufferAddress); + if (*(UINTN *)S3DebugBuffer != (UINTN) -1) { + IdtEntry = (INTERRUPT_GATE_DESCRIPTOR *)(IdtDescriptor->Base + (3 * sizeof (INTERRUPT_GATE_DESCRIPTOR))); + IdtEntry->Offset15To0 = (UINT16)S3DebugBuffer; + IdtEntry->SegmentSelector = (UINT16)AsmReadCs (); + IdtEntry->Attributes = (UINT16)INTERRUPT_GATE_ATTRIBUTE; + IdtEntry->Offset31To16 = (UINT16)(S3DebugBuffer >> 16); + IdtEntry->Offset63To32 = (UINT32)(S3DebugBuffer >> 32); + IdtEntry->Reserved = 0; + } + ); IdtEntry = (INTERRUPT_GATE_DESCRIPTOR *)(IdtDescriptor->Base + (14 * sizeof (INTERRUPT_GATE_DESCRIPTOR))); HookPageFaultHandler (IdtEntry); - - AsmWriteIdtr (IdtDescriptor); } /** -- cgit v1.2.3