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MdePkg/SmmPeriodicSmiLib: Get Periodic SMI Context More Robustly 

The PeriodicSmiDispatchFunction() in SmmPeriodicSmiLib may assert
with "Bad CR signature".

Currently, the SetActivePeriodicSmiLibraryHandler() function
(invoked at the beginning of the PeriodicSmiDispatchFunction()
function) attempts to locate the PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT
structure pointer for the current periodic SMI from a given
EFI_SMM_PERIODIC_TIMER_REGISTER_CONTEXT (RegiserContext) structure
pointer (using the CR macro).

The RegisterContext structure pointer passed to the
PeriodicSmiDispatchFunction() is assumed to point to the same
RegisterContext structure address given to the
SmmPeriodicTimerDispatch2 protocol Register() API in
PeriodicSmiEnable().

However, certain SmmPeriodicTimerDispatch2 implementation may copy
the RegisterContext to a local buffer and pass that address as the
context to PeriodicSmiDispatchFunction() in which case usage of the
CR macro to find the parent structure base fails.

The patch uses the LookupPeriodicSmiLibraryHandler() function to
find the PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT structure pointer.
This works even in this scenario since the DispatchHandle returned
from the SmmPeriodicTimerDispatch2 Register() function uniquely
identifies that registration.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
This commit is contained in:
Ruiyu Ni 2018-05-09 17:36:06 +08:00
parent 7ebad830d6
commit 1e35fcc9ee
1 changed files with 15 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
MdePkg/Library/SmmPeriodicSmiLib/SmmPeriodicSmiLib.c
View File

@ -1,7 +1,7 @@
/** @file
SMM Periodic SMI Library.
Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@ -144,19 +144,6 @@ typedef struct {
UINT64 ElapsedTime;
} PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT;
/**
Macro that returns a pointer to a PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT
structure based on a pointer to a RegisterContext field.
**/
#define PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT_FROM_REGISTER_CONTEXT(a) \
CR ( \
a, \
PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT, \
RegisterContext, \
PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT_SIGNATURE \
)
/**
Macro that returns a pointer to a PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT
structure based on a pointer to a Link field.
@ -280,26 +267,31 @@ LookupPeriodicSmiLibraryHandler (
/**
Internal worker function that sets that active periodic SMI handler based on
the Context used when the periodic SMI handler was registered with the
SMM Periodic Timer Dispatch 2 Protocol. If Context is NULL, then the
the DispatchHandle that was returned when the periodic SMI handler was enabled
with PeriodicSmiEnable(). If DispatchHandle is NULL, then the
state is updated to show that there is not active periodic SMI handler.
A pointer to the active PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT structure
is returned.
@retval NULL Context is NULL.
@param [in] DispatchHandle DispatchHandle that was returned when the periodic
SMI handler was enabled with PeriodicSmiEnable().
This is an optional parameter that may be NULL.
If this parameter is NULL, then the state is updated
to show that there is not active periodic SMI handler.
@retval NULL DispatchHandle is NULL.
@retval other Pointer to the PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT
associated with Context.
associated with DispatchHandle.
**/
PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT *
SetActivePeriodicSmiLibraryHandler (
IN CONST VOID *Context OPTIONAL
IN EFI_HANDLE DispatchHandle OPTIONAL
)
{
if (Context == NULL) {
if (DispatchHandle == NULL) {
gActivePeriodicSmiLibraryHandler = NULL;
} else {
gActivePeriodicSmiLibraryHandler = PERIODIC_SMI_LIBRARY_HANDLER_CONTEXT_FROM_REGISTER_CONTEXT (Context);
gActivePeriodicSmiLibraryHandler = LookupPeriodicSmiLibraryHandler (DispatchHandle);
}
return gActivePeriodicSmiLibraryHandler;
}
@ -798,7 +790,7 @@ PeriodicSmiDispatchFunction (
//
// Set the active periodic SMI handler
//
PeriodicSmiLibraryHandler = SetActivePeriodicSmiLibraryHandler (Context);
PeriodicSmiLibraryHandler = SetActivePeriodicSmiLibraryHandler (DispatchHandle);
if (PeriodicSmiLibraryHandler == NULL) {
return EFI_NOT_FOUND;
}