1 /** @file
2 This module sets default policy for attributes of EfiACPIMemoryNVS and EfiReservedMemoryType.
3
4 This module sets EFI_MEMORY_XP for attributes of EfiACPIMemoryNVS and EfiReservedMemoryType
5 in UEFI memory map, if and only of PropertiesTable is published and has BIT0 set.
6
7 Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
8 This program and the accompanying materials
9 are licensed and made available under the terms and conditions of the BSD License
10 which accompanies this distribution. The full text of the license may be found at
11 http://opensource.org/licenses/bsd-license.php
12
13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
14 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
15
16 **/
17
18 #include <Uefi.h>
19 #include <Library/DebugLib.h>
20 #include <Library/UefiBootServicesTableLib.h>
21 #include <Library/DxeServicesTableLib.h>
22 #include <Library/UefiLib.h>
23 #include <Library/MemoryAllocationLib.h>
24 #include <Guid/EventGroup.h>
25 #include <Guid/PropertiesTable.h>
26
27 /**
28 Converts a number of EFI_PAGEs to a size in bytes.
29
30 NOTE: Do not use EFI_PAGES_TO_SIZE because it handles UINTN only.
31
32 @param Pages The number of EFI_PAGES.
33
34 @return The number of bytes associated with the number of EFI_PAGEs specified
35 by Pages.
36 **/
37 UINT64
EfiPagesToSize(IN UINT64 Pages)38 EfiPagesToSize (
39 IN UINT64 Pages
40 )
41 {
42 return LShiftU64 (Pages, EFI_PAGE_SHIFT);
43 }
44
45 /**
46 Set memory attributes according to default policy.
47
48 @param MemoryMap A pointer to the buffer in which firmware places the current memory map.
49 @param MemoryMapSize Size, in bytes, of the MemoryMap buffer.
50 @param DescriptorSize size, in bytes, of an individual EFI_MEMORY_DESCRIPTOR.
51 **/
52 VOID
SetMemorySpaceAttributesDefault(IN EFI_MEMORY_DESCRIPTOR * MemoryMap,IN UINTN MemoryMapSize,IN UINTN DescriptorSize)53 SetMemorySpaceAttributesDefault (
54 IN EFI_MEMORY_DESCRIPTOR *MemoryMap,
55 IN UINTN MemoryMapSize,
56 IN UINTN DescriptorSize
57 )
58 {
59 EFI_MEMORY_DESCRIPTOR *MemoryMapEntry;
60 EFI_MEMORY_DESCRIPTOR *MemoryMapEnd;
61 EFI_STATUS Status;
62
63 DEBUG ((EFI_D_INFO, "SetMemorySpaceAttributesDefault\n"));
64
65 MemoryMapEntry = MemoryMap;
66 MemoryMapEnd = (EFI_MEMORY_DESCRIPTOR *) ((UINT8 *) MemoryMap + MemoryMapSize);
67 while ((UINTN)MemoryMapEntry < (UINTN)MemoryMapEnd) {
68 if (MemoryMapEntry->PhysicalStart < BASE_1MB) {
69 //
70 // Do not touch memory space below 1MB
71 //
72 MemoryMapEntry = NEXT_MEMORY_DESCRIPTOR (MemoryMapEntry, DescriptorSize);
73 continue;
74 }
75 switch (MemoryMapEntry->Type) {
76 case EfiRuntimeServicesCode:
77 case EfiRuntimeServicesData:
78 //
79 // should be handled later;
80 //
81 break;
82 case EfiReservedMemoryType:
83 case EfiACPIMemoryNVS:
84 //
85 // Handle EfiReservedMemoryType and EfiACPIMemoryNVS, because there might be firmware executable there.
86 //
87 DEBUG ((EFI_D_INFO, "SetMemorySpaceAttributes - %016lx - %016lx (%016lx) ...\n",
88 MemoryMapEntry->PhysicalStart,
89 MemoryMapEntry->PhysicalStart + EfiPagesToSize (MemoryMapEntry->NumberOfPages),
90 MemoryMapEntry->Attribute
91 ));
92 Status = gDS->SetMemorySpaceCapabilities (
93 MemoryMapEntry->PhysicalStart,
94 EfiPagesToSize (MemoryMapEntry->NumberOfPages),
95 MemoryMapEntry->Attribute | EFI_MEMORY_XP
96 );
97 DEBUG ((EFI_D_INFO, "SetMemorySpaceCapabilities - %r\n", Status));
98 break;
99 }
100
101 MemoryMapEntry = NEXT_MEMORY_DESCRIPTOR (MemoryMapEntry, DescriptorSize);
102 }
103
104 return ;
105 }
106
107 /**
108 Update memory attributes according to default policy.
109
110 @param[in] Event The Event this notify function registered to.
111 @param[in] Context Pointer to the context data registered to the Event.
112 **/
113 VOID
114 EFIAPI
UpdateMemoryAttributesDefault(EFI_EVENT Event,VOID * Context)115 UpdateMemoryAttributesDefault (
116 EFI_EVENT Event,
117 VOID *Context
118 )
119 {
120 EFI_STATUS Status;
121 EFI_MEMORY_DESCRIPTOR *MemoryMap;
122 UINTN MemoryMapSize;
123 UINTN MapKey;
124 UINTN DescriptorSize;
125 UINT32 DescriptorVersion;
126 EFI_PROPERTIES_TABLE *PropertiesTable;
127
128 DEBUG ((EFI_D_INFO, "UpdateMemoryAttributesDefault\n"));
129 Status = EfiGetSystemConfigurationTable (&gEfiPropertiesTableGuid, (VOID **) &PropertiesTable);
130 if (EFI_ERROR (Status)) {
131 goto Done;
132 }
133
134 ASSERT (PropertiesTable != NULL);
135
136 DEBUG ((EFI_D_INFO, "MemoryProtectionAttribute - 0x%016lx\n", PropertiesTable->MemoryProtectionAttribute));
137 if ((PropertiesTable->MemoryProtectionAttribute & EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA) == 0) {
138 goto Done;
139 }
140
141 //
142 // Get the EFI memory map.
143 //
144 MemoryMapSize = 0;
145 MemoryMap = NULL;
146 Status = gBS->GetMemoryMap (
147 &MemoryMapSize,
148 MemoryMap,
149 &MapKey,
150 &DescriptorSize,
151 &DescriptorVersion
152 );
153 ASSERT (Status == EFI_BUFFER_TOO_SMALL);
154 do {
155 MemoryMap = (EFI_MEMORY_DESCRIPTOR *) AllocatePool (MemoryMapSize);
156 ASSERT (MemoryMap != NULL);
157 Status = gBS->GetMemoryMap (
158 &MemoryMapSize,
159 MemoryMap,
160 &MapKey,
161 &DescriptorSize,
162 &DescriptorVersion
163 );
164 if (EFI_ERROR (Status)) {
165 FreePool (MemoryMap);
166 }
167 } while (Status == EFI_BUFFER_TOO_SMALL);
168 ASSERT_EFI_ERROR (Status);
169
170 SetMemorySpaceAttributesDefault (MemoryMap, MemoryMapSize, DescriptorSize);
171
172 Done:
173 gBS->CloseEvent (Event);
174
175 return ;
176 }
177
178 /**
179 The entrypoint of properties table attribute driver.
180
181 @param ImageHandle The firmware allocated handle for the EFI image.
182 @param SystemTable A pointer to the EFI System Table.
183
184 @retval EFI_SUCCESS It always returns EFI_SUCCESS.
185
186 **/
187 EFI_STATUS
188 EFIAPI
InitializePropertiesTableAttributesDxe(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)189 InitializePropertiesTableAttributesDxe (
190 IN EFI_HANDLE ImageHandle,
191 IN EFI_SYSTEM_TABLE *SystemTable
192 )
193 {
194 EFI_STATUS Status;
195 EFI_EVENT ReadyToBootEvent;
196
197 Status = gBS->CreateEventEx (
198 EVT_NOTIFY_SIGNAL,
199 TPL_CALLBACK,
200 UpdateMemoryAttributesDefault,
201 NULL,
202 &gEfiEventReadyToBootGuid,
203 &ReadyToBootEvent
204 );
205 ASSERT_EFI_ERROR (Status);
206
207 return EFI_SUCCESS;
208 }
209