StandaloneMmPkg/Core/InstallConfigurationTable.c

   1 /** @file
   2   System Management System Table Services MmInstallConfigurationTable service
   3
   4   Copyright (c) 2009 - 2017, Intel Corporation. All rights reserved.<BR>
   5   Copyright (c) 2016 - 2018, ARM Limited. All rights reserved.<BR>
   6   This program and the accompanying materials are licensed and made available
   7   under the terms and conditions of the BSD License which accompanies this
   8   distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #include "StandaloneMmCore.h"
  17
  18 #define CONFIG_TABLE_SIZE_INCREASED 0x10
  19
  20 UINTN  mMmSystemTableAllocateSize = 0;
  21
  22 /**
  23   The MmInstallConfigurationTable() function is used to maintain the list
  24   of configuration tables that are stored in the System Management System
  25   Table.  The list is stored as an array of (GUID, Pointer) pairs.  The list
  26   must be allocated from pool memory with PoolType set to EfiRuntimeServicesData.
  27
  28   @param  SystemTable      A pointer to the SMM System Table (SMST).
  29   @param  Guid             A pointer to the GUID for the entry to add, update, or remove.
  30   @param  Table            A pointer to the buffer of the table to add.
  31   @param  TableSize        The size of the table to install.
  32
  33   @retval EFI_SUCCESS           The (Guid, Table) pair was added, updated, or removed.
  34   @retval EFI_INVALID_PARAMETER Guid is not valid.
  35   @retval EFI_NOT_FOUND         An attempt was made to delete a non-existent entry.
  36   @retval EFI_OUT_OF_RESOURCES  There is not enough memory available to complete the operation.
  37
  38 **/
  39 EFI_STATUS
  40 EFIAPI
  41 MmInstallConfigurationTable (
  42   IN  CONST EFI_MM_SYSTEM_TABLE    *SystemTable,
  43   IN  CONST EFI_GUID               *Guid,
  44   IN  VOID                         *Table,
  45   IN  UINTN                        TableSize
  46   )
  47 {
  48   UINTN                    Index;
  49   EFI_CONFIGURATION_TABLE  *ConfigurationTable;
  50   EFI_CONFIGURATION_TABLE  *OldTable;
  51
  52   //
  53   // If Guid is NULL, then this operation cannot be performed
  54   //
  55   if (Guid == NULL) {
  56     return EFI_INVALID_PARAMETER;
  57   }
  58
  59   ConfigurationTable = gMmCoreMmst.MmConfigurationTable;
  60
  61   //
  62   // Search all the table for an entry that matches Guid
  63   //
  64   for (Index = 0; Index < gMmCoreMmst.NumberOfTableEntries; Index++) {
  65     if (CompareGuid (Guid, &(ConfigurationTable[Index].VendorGuid))) {
  66       break;
  67     }
  68   }
  69
  70   if (Index < gMmCoreMmst.NumberOfTableEntries) {
  71     //
  72     // A match was found, so this is either a modify or a delete operation
  73     //
  74     if (Table != NULL) {
  75       //
  76       // If Table is not NULL, then this is a modify operation.
  77       // Modify the table entry and return.
  78       //
  79       ConfigurationTable[Index].VendorTable = Table;
  80       return EFI_SUCCESS;
  81     }
  82
  83     //
  84     // A match was found and Table is NULL, so this is a delete operation.
  85     //
  86     gMmCoreMmst.NumberOfTableEntries--;
  87
  88     //
  89     // Copy over deleted entry
  90     //
  91     CopyMem (
  92       &(ConfigurationTable[Index]),
  93       &(ConfigurationTable[Index + 1]),
  94       (gMmCoreMmst.NumberOfTableEntries - Index) * sizeof (EFI_CONFIGURATION_TABLE)
  95       );
  96
  97   } else {
  98     //
  99     // No matching GUIDs were found, so this is an add operation.
 100     //
 101     if (Table == NULL) {
 102       //
 103       // If Table is NULL on an add operation, then return an error.
 104       //
 105       return EFI_NOT_FOUND;
 106     }
 107
 108     //
 109     // Assume that Index == gMmCoreMmst.NumberOfTableEntries
 110     //
 111     if ((Index * sizeof (EFI_CONFIGURATION_TABLE)) >= mMmSystemTableAllocateSize) {
 112       //
 113       // Allocate a table with one additional entry.
 114       //
 115       mMmSystemTableAllocateSize += (CONFIG_TABLE_SIZE_INCREASED * sizeof (EFI_CONFIGURATION_TABLE));
 116       ConfigurationTable = AllocatePool (mMmSystemTableAllocateSize);
 117       if (ConfigurationTable == NULL) {
 118         //
 119         // If a new table could not be allocated, then return an error.
 120         //
 121         return EFI_OUT_OF_RESOURCES;
 122       }
 123
 124       if (gMmCoreMmst.MmConfigurationTable != NULL) {
 125         //
 126         // Copy the old table to the new table.
 127         //
 128         CopyMem (
 129           ConfigurationTable,
 130           gMmCoreMmst.MmConfigurationTable,
 131           Index * sizeof (EFI_CONFIGURATION_TABLE)
 132           );
 133
 134         //
 135         // Record the old table pointer.
 136         //
 137         OldTable = gMmCoreMmst.MmConfigurationTable;
 138
 139         //
 140         // As the MmInstallConfigurationTable() may be re-entered by FreePool() in
 141         // its calling stack, updating System table to the new table pointer must
 142         // be done before calling FreePool() to free the old table.
 143         // It can make sure the gMmCoreMmst.MmConfigurationTable point to the new
 144         // table and avoid the errors of use-after-free to the old table by the
 145         // reenter of MmInstallConfigurationTable() in FreePool()'s calling stack.
 146         //
 147         gMmCoreMmst.MmConfigurationTable = ConfigurationTable;
 148
 149         //
 150         // Free the old table after updating System Table to the new table pointer.
 151         //
 152         FreePool (OldTable);
 153       } else {
 154         //
 155         // Update System Table
 156         //
 157         gMmCoreMmst.MmConfigurationTable = ConfigurationTable;
 158       }
 159     }
 160
 161     //
 162     // Fill in the new entry
 163     //
 164     CopyGuid ((VOID *)&ConfigurationTable[Index].VendorGuid, Guid);
 165     ConfigurationTable[Index].VendorTable = Table;
 166
 167     //
 168     // This is an add operation, so increment the number of table entries
 169     //
 170     gMmCoreMmst.NumberOfTableEntries++;
 171   }
 172
 173   //
 174   // CRC-32 field is ignorable for SMM System Table and should be set to zero
 175   //
 176
 177   return EFI_SUCCESS;
 178 }