MdeModulePkg/Core/PiSmmCore/InstallConfigurationTable.c

   1 /** @file
   2   System Management System Table Services SmmInstallConfigurationTable service
   3
   4   Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "PiSmmCore.h"
  10
  11 #define CONFIG_TABLE_SIZE_INCREASED 0x10
  12
  13 UINTN  mSmmSystemTableAllocateSize = 0;
  14
  15 /**
  16   The SmmInstallConfigurationTable() function is used to maintain the list
  17   of configuration tables that are stored in the System Management System
  18   Table.  The list is stored as an array of (GUID, Pointer) pairs.  The list
  19   must be allocated from pool memory with PoolType set to EfiRuntimeServicesData.
  20
  21   @param  SystemTable      A pointer to the SMM System Table (SMST).
  22   @param  Guid             A pointer to the GUID for the entry to add, update, or remove.
  23   @param  Table            A pointer to the buffer of the table to add.
  24   @param  TableSize        The size of the table to install.
  25
  26   @retval EFI_SUCCESS           The (Guid, Table) pair was added, updated, or removed.
  27   @retval EFI_INVALID_PARAMETER Guid is not valid.
  28   @retval EFI_NOT_FOUND         An attempt was made to delete a non-existent entry.
  29   @retval EFI_OUT_OF_RESOURCES  There is not enough memory available to complete the operation.
  30
  31 **/
  32 EFI_STATUS
  33 EFIAPI
  34 SmmInstallConfigurationTable (
  35   IN  CONST EFI_SMM_SYSTEM_TABLE2  *SystemTable,
  36   IN  CONST EFI_GUID               *Guid,
  37   IN  VOID                         *Table,
  38   IN  UINTN                        TableSize
  39   )
  40 {
  41   UINTN                    Index;
  42   EFI_CONFIGURATION_TABLE  *ConfigurationTable;
  43   EFI_CONFIGURATION_TABLE  *OldTable;
  44
  45   //
  46   // If Guid is NULL, then this operation cannot be performed
  47   //
  48   if (Guid == NULL) {
  49     return EFI_INVALID_PARAMETER;
  50   }
  51
  52   ConfigurationTable = gSmmCoreSmst.SmmConfigurationTable;
  53
  54   //
  55   // Search all the table for an entry that matches Guid
  56   //
  57   for (Index = 0; Index < gSmmCoreSmst.NumberOfTableEntries; Index++) {
  58     if (CompareGuid (Guid, &(ConfigurationTable[Index].VendorGuid))) {
  59       break;
  60     }
  61   }
  62
  63   if (Index < gSmmCoreSmst.NumberOfTableEntries) {
  64     //
  65     // A match was found, so this is either a modify or a delete operation
  66     //
  67     if (Table != NULL) {
  68       //
  69       // If Table is not NULL, then this is a modify operation.
  70       // Modify the table entry and return.
  71       //
  72       ConfigurationTable[Index].VendorTable = Table;
  73       return EFI_SUCCESS;
  74     }
  75
  76     //
  77     // A match was found and Table is NULL, so this is a delete operation.
  78     //
  79     gSmmCoreSmst.NumberOfTableEntries--;
  80
  81     //
  82     // Copy over deleted entry
  83     //
  84     CopyMem (
  85       &(ConfigurationTable[Index]),
  86       &(ConfigurationTable[Index + 1]),
  87       (gSmmCoreSmst.NumberOfTableEntries - Index) * sizeof (EFI_CONFIGURATION_TABLE)
  88       );
  89
  90   } else {
  91     //
  92     // No matching GUIDs were found, so this is an add operation.
  93     //
  94     if (Table == NULL) {
  95       //
  96       // If Table is NULL on an add operation, then return an error.
  97       //
  98       return EFI_NOT_FOUND;
  99     }
 100
 101     //
 102     // Assume that Index == gSmmCoreSmst.NumberOfTableEntries
 103     //
 104     if ((Index * sizeof (EFI_CONFIGURATION_TABLE)) >= mSmmSystemTableAllocateSize) {
 105       //
 106       // Allocate a table with one additional entry.
 107       //
 108       mSmmSystemTableAllocateSize += (CONFIG_TABLE_SIZE_INCREASED * sizeof (EFI_CONFIGURATION_TABLE));
 109       ConfigurationTable = AllocatePool (mSmmSystemTableAllocateSize);
 110       if (ConfigurationTable == NULL) {
 111         //
 112         // If a new table could not be allocated, then return an error.
 113         //
 114         return EFI_OUT_OF_RESOURCES;
 115       }
 116
 117       if (gSmmCoreSmst.SmmConfigurationTable != NULL) {
 118         //
 119         // Copy the old table to the new table.
 120         //
 121         CopyMem (
 122           ConfigurationTable,
 123           gSmmCoreSmst.SmmConfigurationTable,
 124           Index * sizeof (EFI_CONFIGURATION_TABLE)
 125           );
 126
 127         //
 128         // Record the old table pointer.
 129         //
 130         OldTable = gSmmCoreSmst.SmmConfigurationTable;
 131
 132         //
 133         // As the SmmInstallConfigurationTable() may be re-entered by FreePool() in
 134         // its calling stack, updating System table to the new table pointer must
 135         // be done before calling FreePool() to free the old table.
 136         // It can make sure the gSmmCoreSmst.SmmConfigurationTable point to the new
 137         // table and avoid the errors of use-after-free to the old table by the
 138         // reenter of SmmInstallConfigurationTable() in FreePool()'s calling stack.
 139         //
 140         gSmmCoreSmst.SmmConfigurationTable = ConfigurationTable;
 141
 142         //
 143         // Free the old table after updating System Table to the new table pointer.
 144         //
 145         FreePool (OldTable);
 146       } else {
 147         //
 148         // Update System Table
 149         //
 150         gSmmCoreSmst.SmmConfigurationTable = ConfigurationTable;
 151       }
 152     }
 153
 154     //
 155     // Fill in the new entry
 156     //
 157     CopyGuid ((VOID *)&ConfigurationTable[Index].VendorGuid, Guid);
 158     ConfigurationTable[Index].VendorTable = Table;
 159
 160     //
 161     // This is an add operation, so increment the number of table entries
 162     //
 163     gSmmCoreSmst.NumberOfTableEntries++;
 164   }
 165
 166   //
 167   // CRC-32 field is ignorable for SMM System Table and should be set to zero
 168   //
 169
 170   return EFI_SUCCESS;
 171 }