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e63da9f0 JW |
1 | /** @file\r |
2 | UEFI Heap Guard functions.\r | |
3 | \r | |
8b13bca9 | 4 | Copyright (c) 2017-2018, Intel Corporation. All rights reserved.<BR>\r |
e63da9f0 JW |
5 | This program and the accompanying materials\r |
6 | are licensed and made available under the terms and conditions of the BSD License\r | |
7 | which accompanies this distribution. The full text of the license may be found at\r | |
8 | http://opensource.org/licenses/bsd-license.php\r | |
9 | \r | |
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | \r | |
13 | **/\r | |
14 | \r | |
15 | #include "DxeMain.h"\r | |
16 | #include "Imem.h"\r | |
17 | #include "HeapGuard.h"\r | |
18 | \r | |
19 | //\r | |
20 | // Global to avoid infinite reentrance of memory allocation when updating\r | |
21 | // page table attributes, which may need allocate pages for new PDE/PTE.\r | |
22 | //\r | |
23 | GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding = FALSE;\r | |
24 | \r | |
25 | //\r | |
26 | // Pointer to table tracking the Guarded memory with bitmap, in which '1'\r | |
27 | // is used to indicate memory guarded. '0' might be free memory or Guard\r | |
28 | // page itself, depending on status of memory adjacent to it.\r | |
29 | //\r | |
30 | GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;\r | |
31 | \r | |
32 | //\r | |
33 | // Current depth level of map table pointed by mGuardedMemoryMap.\r | |
34 | // mMapLevel must be initialized at least by 1. It will be automatically\r | |
35 | // updated according to the address of memory just tracked.\r | |
36 | //\r | |
37 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;\r | |
38 | \r | |
39 | //\r | |
40 | // Shift and mask for each level of map table\r | |
41 | //\r | |
42 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]\r | |
43 | = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;\r | |
44 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]\r | |
45 | = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;\r | |
46 | \r | |
63ebde8e JW |
47 | //\r |
48 | // Used for promoting freed but not used pages.\r | |
49 | //\r | |
50 | GLOBAL_REMOVE_IF_UNREFERENCED EFI_PHYSICAL_ADDRESS mLastPromotedPage = BASE_4GB;\r | |
51 | \r | |
e63da9f0 JW |
52 | /**\r |
53 | Set corresponding bits in bitmap table to 1 according to the address.\r | |
54 | \r | |
55 | @param[in] Address Start address to set for.\r | |
56 | @param[in] BitNumber Number of bits to set.\r | |
57 | @param[in] BitMap Pointer to bitmap which covers the Address.\r | |
58 | \r | |
59 | @return VOID.\r | |
60 | **/\r | |
61 | STATIC\r | |
62 | VOID\r | |
63 | SetBits (\r | |
64 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
65 | IN UINTN BitNumber,\r | |
66 | IN UINT64 *BitMap\r | |
67 | )\r | |
68 | {\r | |
69 | UINTN Lsbs;\r | |
70 | UINTN Qwords;\r | |
71 | UINTN Msbs;\r | |
72 | UINTN StartBit;\r | |
73 | UINTN EndBit;\r | |
74 | \r | |
75 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);\r | |
76 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
77 | \r | |
36f2f049 | 78 | if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) {\r |
e63da9f0 JW |
79 | Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %\r |
80 | GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
81 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
82 | Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
83 | } else {\r | |
84 | Msbs = BitNumber;\r | |
85 | Lsbs = 0;\r | |
86 | Qwords = 0;\r | |
87 | }\r | |
88 | \r | |
89 | if (Msbs > 0) {\r | |
90 | *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);\r | |
91 | BitMap += 1;\r | |
92 | }\r | |
93 | \r | |
94 | if (Qwords > 0) {\r | |
95 | SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,\r | |
96 | (UINT64)-1);\r | |
97 | BitMap += Qwords;\r | |
98 | }\r | |
99 | \r | |
100 | if (Lsbs > 0) {\r | |
101 | *BitMap |= (LShiftU64 (1, Lsbs) - 1);\r | |
102 | }\r | |
103 | }\r | |
104 | \r | |
105 | /**\r | |
106 | Set corresponding bits in bitmap table to 0 according to the address.\r | |
107 | \r | |
108 | @param[in] Address Start address to set for.\r | |
109 | @param[in] BitNumber Number of bits to set.\r | |
110 | @param[in] BitMap Pointer to bitmap which covers the Address.\r | |
111 | \r | |
112 | @return VOID.\r | |
113 | **/\r | |
114 | STATIC\r | |
115 | VOID\r | |
116 | ClearBits (\r | |
117 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
118 | IN UINTN BitNumber,\r | |
119 | IN UINT64 *BitMap\r | |
120 | )\r | |
121 | {\r | |
122 | UINTN Lsbs;\r | |
123 | UINTN Qwords;\r | |
124 | UINTN Msbs;\r | |
125 | UINTN StartBit;\r | |
126 | UINTN EndBit;\r | |
127 | \r | |
128 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);\r | |
129 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
130 | \r | |
36f2f049 | 131 | if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) {\r |
e63da9f0 JW |
132 | Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %\r |
133 | GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
134 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
135 | Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
136 | } else {\r | |
137 | Msbs = BitNumber;\r | |
138 | Lsbs = 0;\r | |
139 | Qwords = 0;\r | |
140 | }\r | |
141 | \r | |
142 | if (Msbs > 0) {\r | |
143 | *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);\r | |
144 | BitMap += 1;\r | |
145 | }\r | |
146 | \r | |
147 | if (Qwords > 0) {\r | |
148 | SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);\r | |
149 | BitMap += Qwords;\r | |
150 | }\r | |
151 | \r | |
152 | if (Lsbs > 0) {\r | |
153 | *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);\r | |
154 | }\r | |
155 | }\r | |
156 | \r | |
157 | /**\r | |
158 | Get corresponding bits in bitmap table according to the address.\r | |
159 | \r | |
160 | The value of bit 0 corresponds to the status of memory at given Address.\r | |
161 | No more than 64 bits can be retrieved in one call.\r | |
162 | \r | |
163 | @param[in] Address Start address to retrieve bits for.\r | |
164 | @param[in] BitNumber Number of bits to get.\r | |
165 | @param[in] BitMap Pointer to bitmap which covers the Address.\r | |
166 | \r | |
167 | @return An integer containing the bits information.\r | |
168 | **/\r | |
169 | STATIC\r | |
170 | UINT64\r | |
171 | GetBits (\r | |
172 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
173 | IN UINTN BitNumber,\r | |
174 | IN UINT64 *BitMap\r | |
175 | )\r | |
176 | {\r | |
177 | UINTN StartBit;\r | |
178 | UINTN EndBit;\r | |
179 | UINTN Lsbs;\r | |
180 | UINTN Msbs;\r | |
181 | UINT64 Result;\r | |
182 | \r | |
183 | ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);\r | |
184 | \r | |
185 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);\r | |
186 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
187 | \r | |
188 | if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {\r | |
189 | Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;\r | |
190 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;\r | |
191 | } else {\r | |
192 | Msbs = BitNumber;\r | |
193 | Lsbs = 0;\r | |
194 | }\r | |
195 | \r | |
36f2f049 JW |
196 | if (StartBit == 0 && BitNumber == GUARDED_HEAP_MAP_ENTRY_BITS) {\r |
197 | Result = *BitMap;\r | |
198 | } else {\r | |
199 | Result = RShiftU64((*BitMap), StartBit) & (LShiftU64(1, Msbs) - 1);\r | |
200 | if (Lsbs > 0) {\r | |
201 | BitMap += 1;\r | |
202 | Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);\r | |
203 | }\r | |
e63da9f0 JW |
204 | }\r |
205 | \r | |
206 | return Result;\r | |
207 | }\r | |
208 | \r | |
209 | /**\r | |
210 | Locate the pointer of bitmap from the guarded memory bitmap tables, which\r | |
211 | covers the given Address.\r | |
212 | \r | |
213 | @param[in] Address Start address to search the bitmap for.\r | |
214 | @param[in] AllocMapUnit Flag to indicate memory allocation for the table.\r | |
215 | @param[out] BitMap Pointer to bitmap which covers the Address.\r | |
216 | \r | |
217 | @return The bit number from given Address to the end of current map table.\r | |
218 | **/\r | |
219 | UINTN\r | |
220 | FindGuardedMemoryMap (\r | |
221 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
222 | IN BOOLEAN AllocMapUnit,\r | |
223 | OUT UINT64 **BitMap\r | |
224 | )\r | |
225 | {\r | |
226 | UINTN Level;\r | |
227 | UINT64 *GuardMap;\r | |
228 | UINT64 MapMemory;\r | |
229 | UINTN Index;\r | |
230 | UINTN Size;\r | |
231 | UINTN BitsToUnitEnd;\r | |
232 | EFI_STATUS Status;\r | |
233 | \r | |
234 | //\r | |
235 | // Adjust current map table depth according to the address to access\r | |
236 | //\r | |
dd12683e JW |
237 | while (AllocMapUnit &&\r |
238 | mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH &&\r | |
e63da9f0 JW |
239 | RShiftU64 (\r |
240 | Address,\r | |
241 | mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]\r | |
242 | ) != 0) {\r | |
243 | \r | |
244 | if (mGuardedMemoryMap != 0) {\r | |
245 | Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)\r | |
246 | * GUARDED_HEAP_MAP_ENTRY_BYTES;\r | |
247 | Status = CoreInternalAllocatePages (\r | |
248 | AllocateAnyPages,\r | |
249 | EfiBootServicesData,\r | |
250 | EFI_SIZE_TO_PAGES (Size),\r | |
251 | &MapMemory,\r | |
252 | FALSE\r | |
253 | );\r | |
254 | ASSERT_EFI_ERROR (Status);\r | |
255 | ASSERT (MapMemory != 0);\r | |
256 | \r | |
257 | SetMem ((VOID *)(UINTN)MapMemory, Size, 0);\r | |
258 | \r | |
259 | *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;\r | |
260 | mGuardedMemoryMap = MapMemory;\r | |
261 | }\r | |
262 | \r | |
263 | mMapLevel++;\r | |
264 | \r | |
265 | }\r | |
266 | \r | |
267 | GuardMap = &mGuardedMemoryMap;\r | |
268 | for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r | |
269 | Level < GUARDED_HEAP_MAP_TABLE_DEPTH;\r | |
270 | ++Level) {\r | |
271 | \r | |
272 | if (*GuardMap == 0) {\r | |
273 | if (!AllocMapUnit) {\r | |
274 | GuardMap = NULL;\r | |
275 | break;\r | |
276 | }\r | |
277 | \r | |
278 | Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;\r | |
279 | Status = CoreInternalAllocatePages (\r | |
280 | AllocateAnyPages,\r | |
281 | EfiBootServicesData,\r | |
282 | EFI_SIZE_TO_PAGES (Size),\r | |
283 | &MapMemory,\r | |
284 | FALSE\r | |
285 | );\r | |
286 | ASSERT_EFI_ERROR (Status);\r | |
287 | ASSERT (MapMemory != 0);\r | |
288 | \r | |
289 | SetMem ((VOID *)(UINTN)MapMemory, Size, 0);\r | |
290 | *GuardMap = MapMemory;\r | |
291 | }\r | |
292 | \r | |
293 | Index = (UINTN)RShiftU64 (Address, mLevelShift[Level]);\r | |
294 | Index &= mLevelMask[Level];\r | |
295 | GuardMap = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));\r | |
296 | \r | |
297 | }\r | |
298 | \r | |
299 | BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);\r | |
300 | *BitMap = GuardMap;\r | |
301 | \r | |
302 | return BitsToUnitEnd;\r | |
303 | }\r | |
304 | \r | |
305 | /**\r | |
306 | Set corresponding bits in bitmap table to 1 according to given memory range.\r | |
307 | \r | |
308 | @param[in] Address Memory address to guard from.\r | |
309 | @param[in] NumberOfPages Number of pages to guard.\r | |
310 | \r | |
311 | @return VOID.\r | |
312 | **/\r | |
313 | VOID\r | |
314 | EFIAPI\r | |
315 | SetGuardedMemoryBits (\r | |
316 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
317 | IN UINTN NumberOfPages\r | |
318 | )\r | |
319 | {\r | |
320 | UINT64 *BitMap;\r | |
321 | UINTN Bits;\r | |
322 | UINTN BitsToUnitEnd;\r | |
323 | \r | |
324 | while (NumberOfPages > 0) {\r | |
325 | BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);\r | |
326 | ASSERT (BitMap != NULL);\r | |
327 | \r | |
328 | if (NumberOfPages > BitsToUnitEnd) {\r | |
329 | // Cross map unit\r | |
330 | Bits = BitsToUnitEnd;\r | |
331 | } else {\r | |
332 | Bits = NumberOfPages;\r | |
333 | }\r | |
334 | \r | |
335 | SetBits (Address, Bits, BitMap);\r | |
336 | \r | |
337 | NumberOfPages -= Bits;\r | |
338 | Address += EFI_PAGES_TO_SIZE (Bits);\r | |
339 | }\r | |
340 | }\r | |
341 | \r | |
342 | /**\r | |
343 | Clear corresponding bits in bitmap table according to given memory range.\r | |
344 | \r | |
345 | @param[in] Address Memory address to unset from.\r | |
346 | @param[in] NumberOfPages Number of pages to unset guard.\r | |
347 | \r | |
348 | @return VOID.\r | |
349 | **/\r | |
350 | VOID\r | |
351 | EFIAPI\r | |
352 | ClearGuardedMemoryBits (\r | |
353 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
354 | IN UINTN NumberOfPages\r | |
355 | )\r | |
356 | {\r | |
357 | UINT64 *BitMap;\r | |
358 | UINTN Bits;\r | |
359 | UINTN BitsToUnitEnd;\r | |
360 | \r | |
361 | while (NumberOfPages > 0) {\r | |
362 | BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);\r | |
363 | ASSERT (BitMap != NULL);\r | |
364 | \r | |
365 | if (NumberOfPages > BitsToUnitEnd) {\r | |
366 | // Cross map unit\r | |
367 | Bits = BitsToUnitEnd;\r | |
368 | } else {\r | |
369 | Bits = NumberOfPages;\r | |
370 | }\r | |
371 | \r | |
372 | ClearBits (Address, Bits, BitMap);\r | |
373 | \r | |
374 | NumberOfPages -= Bits;\r | |
375 | Address += EFI_PAGES_TO_SIZE (Bits);\r | |
376 | }\r | |
377 | }\r | |
378 | \r | |
379 | /**\r | |
380 | Retrieve corresponding bits in bitmap table according to given memory range.\r | |
381 | \r | |
382 | @param[in] Address Memory address to retrieve from.\r | |
383 | @param[in] NumberOfPages Number of pages to retrieve.\r | |
384 | \r | |
385 | @return An integer containing the guarded memory bitmap.\r | |
386 | **/\r | |
63ebde8e | 387 | UINT64\r |
e63da9f0 JW |
388 | GetGuardedMemoryBits (\r |
389 | IN EFI_PHYSICAL_ADDRESS Address,\r | |
390 | IN UINTN NumberOfPages\r | |
391 | )\r | |
392 | {\r | |
393 | UINT64 *BitMap;\r | |
394 | UINTN Bits;\r | |
63ebde8e | 395 | UINT64 Result;\r |
e63da9f0 JW |
396 | UINTN Shift;\r |
397 | UINTN BitsToUnitEnd;\r | |
398 | \r | |
399 | ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);\r | |
400 | \r | |
401 | Result = 0;\r | |
402 | Shift = 0;\r | |
403 | while (NumberOfPages > 0) {\r | |
404 | BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);\r | |
405 | \r | |
406 | if (NumberOfPages > BitsToUnitEnd) {\r | |
407 | // Cross map unit\r | |
408 | Bits = BitsToUnitEnd;\r | |
409 | } else {\r | |
410 | Bits = NumberOfPages;\r | |
411 | }\r | |
412 | \r | |
413 | if (BitMap != NULL) {\r | |
414 | Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);\r | |
415 | }\r | |
416 | \r | |
417 | Shift += Bits;\r | |
418 | NumberOfPages -= Bits;\r | |
419 | Address += EFI_PAGES_TO_SIZE (Bits);\r | |
420 | }\r | |
421 | \r | |
422 | return Result;\r | |
423 | }\r | |
424 | \r | |
425 | /**\r | |
426 | Get bit value in bitmap table for the given address.\r | |
427 | \r | |
428 | @param[in] Address The address to retrieve for.\r | |
429 | \r | |
430 | @return 1 or 0.\r | |
431 | **/\r | |
432 | UINTN\r | |
433 | EFIAPI\r | |
434 | GetGuardMapBit (\r | |
435 | IN EFI_PHYSICAL_ADDRESS Address\r | |
436 | )\r | |
437 | {\r | |
438 | UINT64 *GuardMap;\r | |
439 | \r | |
440 | FindGuardedMemoryMap (Address, FALSE, &GuardMap);\r | |
441 | if (GuardMap != NULL) {\r | |
442 | if (RShiftU64 (*GuardMap,\r | |
443 | GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {\r | |
444 | return 1;\r | |
445 | }\r | |
446 | }\r | |
447 | \r | |
448 | return 0;\r | |
449 | }\r | |
450 | \r | |
e63da9f0 JW |
451 | \r |
452 | /**\r | |
453 | Check to see if the page at the given address is a Guard page or not.\r | |
454 | \r | |
455 | @param[in] Address The address to check for.\r | |
456 | \r | |
457 | @return TRUE The page at Address is a Guard page.\r | |
458 | @return FALSE The page at Address is not a Guard page.\r | |
459 | **/\r | |
460 | BOOLEAN\r | |
461 | EFIAPI\r | |
462 | IsGuardPage (\r | |
463 | IN EFI_PHYSICAL_ADDRESS Address\r | |
464 | )\r | |
465 | {\r | |
e5001ab7 | 466 | UINT64 BitMap;\r |
e63da9f0 JW |
467 | \r |
468 | //\r | |
469 | // There must be at least one guarded page before and/or after given\r | |
470 | // address if it's a Guard page. The bitmap pattern should be one of\r | |
471 | // 001, 100 and 101\r | |
472 | //\r | |
473 | BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);\r | |
474 | return ((BitMap == BIT0) || (BitMap == BIT2) || (BitMap == (BIT2 | BIT0)));\r | |
475 | }\r | |
476 | \r | |
e63da9f0 JW |
477 | \r |
478 | /**\r | |
479 | Check to see if the page at the given address is guarded or not.\r | |
480 | \r | |
481 | @param[in] Address The address to check for.\r | |
482 | \r | |
483 | @return TRUE The page at Address is guarded.\r | |
484 | @return FALSE The page at Address is not guarded.\r | |
485 | **/\r | |
486 | BOOLEAN\r | |
487 | EFIAPI\r | |
488 | IsMemoryGuarded (\r | |
489 | IN EFI_PHYSICAL_ADDRESS Address\r | |
490 | )\r | |
491 | {\r | |
492 | return (GetGuardMapBit (Address) == 1);\r | |
493 | }\r | |
494 | \r | |
495 | /**\r | |
496 | Set the page at the given address to be a Guard page.\r | |
497 | \r | |
498 | This is done by changing the page table attribute to be NOT PRSENT.\r | |
499 | \r | |
500 | @param[in] BaseAddress Page address to Guard at\r | |
501 | \r | |
502 | @return VOID\r | |
503 | **/\r | |
504 | VOID\r | |
505 | EFIAPI\r | |
506 | SetGuardPage (\r | |
507 | IN EFI_PHYSICAL_ADDRESS BaseAddress\r | |
508 | )\r | |
509 | {\r | |
a5cd613c JW |
510 | EFI_STATUS Status;\r |
511 | \r | |
7fef06af JW |
512 | if (gCpu == NULL) {\r |
513 | return;\r | |
514 | }\r | |
515 | \r | |
e63da9f0 JW |
516 | //\r |
517 | // Set flag to make sure allocating memory without GUARD for page table\r | |
518 | // operation; otherwise infinite loops could be caused.\r | |
519 | //\r | |
520 | mOnGuarding = TRUE;\r | |
521 | //\r | |
522 | // Note: This might overwrite other attributes needed by other features,\r | |
c44218e5 | 523 | // such as NX memory protection.\r |
e63da9f0 | 524 | //\r |
a5cd613c JW |
525 | Status = gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);\r |
526 | ASSERT_EFI_ERROR (Status);\r | |
e63da9f0 JW |
527 | mOnGuarding = FALSE;\r |
528 | }\r | |
529 | \r | |
530 | /**\r | |
531 | Unset the Guard page at the given address to the normal memory.\r | |
532 | \r | |
533 | This is done by changing the page table attribute to be PRSENT.\r | |
534 | \r | |
535 | @param[in] BaseAddress Page address to Guard at.\r | |
536 | \r | |
537 | @return VOID.\r | |
538 | **/\r | |
539 | VOID\r | |
540 | EFIAPI\r | |
541 | UnsetGuardPage (\r | |
542 | IN EFI_PHYSICAL_ADDRESS BaseAddress\r | |
543 | )\r | |
544 | {\r | |
c44218e5 | 545 | UINT64 Attributes;\r |
a5cd613c | 546 | EFI_STATUS Status;\r |
c44218e5 | 547 | \r |
7fef06af JW |
548 | if (gCpu == NULL) {\r |
549 | return;\r | |
550 | }\r | |
551 | \r | |
c44218e5 JW |
552 | //\r |
553 | // Once the Guard page is unset, it will be freed back to memory pool. NX\r | |
554 | // memory protection must be restored for this page if NX is enabled for free\r | |
555 | // memory.\r | |
556 | //\r | |
557 | Attributes = 0;\r | |
558 | if ((PcdGet64 (PcdDxeNxMemoryProtectionPolicy) & (1 << EfiConventionalMemory)) != 0) {\r | |
559 | Attributes |= EFI_MEMORY_XP;\r | |
560 | }\r | |
561 | \r | |
e63da9f0 JW |
562 | //\r |
563 | // Set flag to make sure allocating memory without GUARD for page table\r | |
564 | // operation; otherwise infinite loops could be caused.\r | |
565 | //\r | |
566 | mOnGuarding = TRUE;\r | |
567 | //\r | |
568 | // Note: This might overwrite other attributes needed by other features,\r | |
569 | // such as memory protection (NX). Please make sure they are not enabled\r | |
570 | // at the same time.\r | |
571 | //\r | |
a5cd613c JW |
572 | Status = gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, Attributes);\r |
573 | ASSERT_EFI_ERROR (Status);\r | |
e63da9f0 JW |
574 | mOnGuarding = FALSE;\r |
575 | }\r | |
576 | \r | |
577 | /**\r | |
578 | Check to see if the memory at the given address should be guarded or not.\r | |
579 | \r | |
580 | @param[in] MemoryType Memory type to check.\r | |
581 | @param[in] AllocateType Allocation type to check.\r | |
582 | @param[in] PageOrPool Indicate a page allocation or pool allocation.\r | |
583 | \r | |
584 | \r | |
585 | @return TRUE The given type of memory should be guarded.\r | |
586 | @return FALSE The given type of memory should not be guarded.\r | |
587 | **/\r | |
588 | BOOLEAN\r | |
589 | IsMemoryTypeToGuard (\r | |
590 | IN EFI_MEMORY_TYPE MemoryType,\r | |
591 | IN EFI_ALLOCATE_TYPE AllocateType,\r | |
592 | IN UINT8 PageOrPool\r | |
593 | )\r | |
594 | {\r | |
595 | UINT64 TestBit;\r | |
596 | UINT64 ConfigBit;\r | |
e63da9f0 | 597 | \r |
7fef06af | 598 | if (AllocateType == AllocateAddress) {\r |
e63da9f0 JW |
599 | return FALSE;\r |
600 | }\r | |
601 | \r | |
e63da9f0 JW |
602 | if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0) {\r |
603 | return FALSE;\r | |
604 | }\r | |
605 | \r | |
606 | if (PageOrPool == GUARD_HEAP_TYPE_POOL) {\r | |
607 | ConfigBit = PcdGet64 (PcdHeapGuardPoolType);\r | |
608 | } else if (PageOrPool == GUARD_HEAP_TYPE_PAGE) {\r | |
609 | ConfigBit = PcdGet64 (PcdHeapGuardPageType);\r | |
610 | } else {\r | |
611 | ConfigBit = (UINT64)-1;\r | |
612 | }\r | |
613 | \r | |
614 | if ((UINT32)MemoryType >= MEMORY_TYPE_OS_RESERVED_MIN) {\r | |
615 | TestBit = BIT63;\r | |
616 | } else if ((UINT32) MemoryType >= MEMORY_TYPE_OEM_RESERVED_MIN) {\r | |
617 | TestBit = BIT62;\r | |
618 | } else if (MemoryType < EfiMaxMemoryType) {\r | |
619 | TestBit = LShiftU64 (1, MemoryType);\r | |
620 | } else if (MemoryType == EfiMaxMemoryType) {\r | |
621 | TestBit = (UINT64)-1;\r | |
622 | } else {\r | |
623 | TestBit = 0;\r | |
624 | }\r | |
625 | \r | |
626 | return ((ConfigBit & TestBit) != 0);\r | |
627 | }\r | |
628 | \r | |
629 | /**\r | |
630 | Check to see if the pool at the given address should be guarded or not.\r | |
631 | \r | |
632 | @param[in] MemoryType Pool type to check.\r | |
633 | \r | |
634 | \r | |
635 | @return TRUE The given type of pool should be guarded.\r | |
636 | @return FALSE The given type of pool should not be guarded.\r | |
637 | **/\r | |
638 | BOOLEAN\r | |
639 | IsPoolTypeToGuard (\r | |
640 | IN EFI_MEMORY_TYPE MemoryType\r | |
641 | )\r | |
642 | {\r | |
643 | return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,\r | |
644 | GUARD_HEAP_TYPE_POOL);\r | |
645 | }\r | |
646 | \r | |
647 | /**\r | |
648 | Check to see if the page at the given address should be guarded or not.\r | |
649 | \r | |
650 | @param[in] MemoryType Page type to check.\r | |
651 | @param[in] AllocateType Allocation type to check.\r | |
652 | \r | |
653 | @return TRUE The given type of page should be guarded.\r | |
654 | @return FALSE The given type of page should not be guarded.\r | |
655 | **/\r | |
656 | BOOLEAN\r | |
657 | IsPageTypeToGuard (\r | |
658 | IN EFI_MEMORY_TYPE MemoryType,\r | |
659 | IN EFI_ALLOCATE_TYPE AllocateType\r | |
660 | )\r | |
661 | {\r | |
662 | return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);\r | |
663 | }\r | |
664 | \r | |
a6a0a597 JW |
665 | /**\r |
666 | Check to see if the heap guard is enabled for page and/or pool allocation.\r | |
667 | \r | |
63ebde8e JW |
668 | @param[in] GuardType Specify the sub-type(s) of Heap Guard.\r |
669 | \r | |
a6a0a597 JW |
670 | @return TRUE/FALSE.\r |
671 | **/\r | |
672 | BOOLEAN\r | |
673 | IsHeapGuardEnabled (\r | |
63ebde8e | 674 | UINT8 GuardType\r |
a6a0a597 JW |
675 | )\r |
676 | {\r | |
63ebde8e | 677 | return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages, GuardType);\r |
a6a0a597 JW |
678 | }\r |
679 | \r | |
e63da9f0 JW |
680 | /**\r |
681 | Set head Guard and tail Guard for the given memory range.\r | |
682 | \r | |
683 | @param[in] Memory Base address of memory to set guard for.\r | |
684 | @param[in] NumberOfPages Memory size in pages.\r | |
685 | \r | |
686 | @return VOID\r | |
687 | **/\r | |
688 | VOID\r | |
689 | SetGuardForMemory (\r | |
690 | IN EFI_PHYSICAL_ADDRESS Memory,\r | |
691 | IN UINTN NumberOfPages\r | |
692 | )\r | |
693 | {\r | |
694 | EFI_PHYSICAL_ADDRESS GuardPage;\r | |
695 | \r | |
696 | //\r | |
697 | // Set tail Guard\r | |
698 | //\r | |
699 | GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);\r | |
700 | if (!IsGuardPage (GuardPage)) {\r | |
701 | SetGuardPage (GuardPage);\r | |
702 | }\r | |
703 | \r | |
704 | // Set head Guard\r | |
705 | GuardPage = Memory - EFI_PAGES_TO_SIZE (1);\r | |
706 | if (!IsGuardPage (GuardPage)) {\r | |
707 | SetGuardPage (GuardPage);\r | |
708 | }\r | |
709 | \r | |
710 | //\r | |
711 | // Mark the memory range as Guarded\r | |
712 | //\r | |
713 | SetGuardedMemoryBits (Memory, NumberOfPages);\r | |
714 | }\r | |
715 | \r | |
716 | /**\r | |
717 | Unset head Guard and tail Guard for the given memory range.\r | |
718 | \r | |
719 | @param[in] Memory Base address of memory to unset guard for.\r | |
720 | @param[in] NumberOfPages Memory size in pages.\r | |
721 | \r | |
722 | @return VOID\r | |
723 | **/\r | |
724 | VOID\r | |
725 | UnsetGuardForMemory (\r | |
726 | IN EFI_PHYSICAL_ADDRESS Memory,\r | |
727 | IN UINTN NumberOfPages\r | |
728 | )\r | |
729 | {\r | |
730 | EFI_PHYSICAL_ADDRESS GuardPage;\r | |
6cf0a677 | 731 | UINT64 GuardBitmap;\r |
e63da9f0 JW |
732 | \r |
733 | if (NumberOfPages == 0) {\r | |
734 | return;\r | |
735 | }\r | |
736 | \r | |
737 | //\r | |
738 | // Head Guard must be one page before, if any.\r | |
739 | //\r | |
6cf0a677 JW |
740 | // MSB-> 1 0 <-LSB\r |
741 | // -------------------\r | |
742 | // Head Guard -> 0 1 -> Don't free Head Guard (shared Guard)\r | |
743 | // Head Guard -> 0 0 -> Free Head Guard either (not shared Guard)\r | |
744 | // 1 X -> Don't free first page (need a new Guard)\r | |
745 | // (it'll be turned into a Guard page later)\r | |
746 | // -------------------\r | |
747 | // Start -> -1 -2\r | |
748 | //\r | |
e63da9f0 | 749 | GuardPage = Memory - EFI_PAGES_TO_SIZE (1);\r |
6cf0a677 JW |
750 | GuardBitmap = GetGuardedMemoryBits (Memory - EFI_PAGES_TO_SIZE (2), 2);\r |
751 | if ((GuardBitmap & BIT1) == 0) {\r | |
752 | //\r | |
753 | // Head Guard exists.\r | |
754 | //\r | |
755 | if ((GuardBitmap & BIT0) == 0) {\r | |
e63da9f0 JW |
756 | //\r |
757 | // If the head Guard is not a tail Guard of adjacent memory block,\r | |
758 | // unset it.\r | |
759 | //\r | |
760 | UnsetGuardPage (GuardPage);\r | |
761 | }\r | |
6cf0a677 | 762 | } else {\r |
e63da9f0 JW |
763 | //\r |
764 | // Pages before memory to free are still in Guard. It's a partial free\r | |
765 | // case. Turn first page of memory block to free into a new Guard.\r | |
766 | //\r | |
767 | SetGuardPage (Memory);\r | |
768 | }\r | |
769 | \r | |
770 | //\r | |
771 | // Tail Guard must be the page after this memory block to free, if any.\r | |
772 | //\r | |
6cf0a677 JW |
773 | // MSB-> 1 0 <-LSB\r |
774 | // --------------------\r | |
775 | // 1 0 <- Tail Guard -> Don't free Tail Guard (shared Guard)\r | |
776 | // 0 0 <- Tail Guard -> Free Tail Guard either (not shared Guard)\r | |
777 | // X 1 -> Don't free last page (need a new Guard)\r | |
778 | // (it'll be turned into a Guard page later)\r | |
779 | // --------------------\r | |
780 | // +1 +0 <- End\r | |
781 | //\r | |
e63da9f0 | 782 | GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);\r |
6cf0a677 JW |
783 | GuardBitmap = GetGuardedMemoryBits (GuardPage, 2);\r |
784 | if ((GuardBitmap & BIT0) == 0) {\r | |
785 | //\r | |
786 | // Tail Guard exists.\r | |
787 | //\r | |
788 | if ((GuardBitmap & BIT1) == 0) {\r | |
e63da9f0 JW |
789 | //\r |
790 | // If the tail Guard is not a head Guard of adjacent memory block,\r | |
791 | // free it; otherwise, keep it.\r | |
792 | //\r | |
793 | UnsetGuardPage (GuardPage);\r | |
794 | }\r | |
6cf0a677 | 795 | } else {\r |
e63da9f0 JW |
796 | //\r |
797 | // Pages after memory to free are still in Guard. It's a partial free\r | |
798 | // case. We need to keep one page to be a head Guard.\r | |
799 | //\r | |
800 | SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));\r | |
801 | }\r | |
802 | \r | |
803 | //\r | |
804 | // No matter what, we just clear the mark of the Guarded memory.\r | |
805 | //\r | |
806 | ClearGuardedMemoryBits(Memory, NumberOfPages);\r | |
807 | }\r | |
808 | \r | |
809 | /**\r | |
810 | Adjust address of free memory according to existing and/or required Guard.\r | |
811 | \r | |
812 | This function will check if there're existing Guard pages of adjacent\r | |
813 | memory blocks, and try to use it as the Guard page of the memory to be\r | |
814 | allocated.\r | |
815 | \r | |
816 | @param[in] Start Start address of free memory block.\r | |
817 | @param[in] Size Size of free memory block.\r | |
818 | @param[in] SizeRequested Size of memory to allocate.\r | |
819 | \r | |
820 | @return The end address of memory block found.\r | |
821 | @return 0 if no enough space for the required size of memory and its Guard.\r | |
822 | **/\r | |
823 | UINT64\r | |
824 | AdjustMemoryS (\r | |
825 | IN UINT64 Start,\r | |
826 | IN UINT64 Size,\r | |
827 | IN UINT64 SizeRequested\r | |
828 | )\r | |
829 | {\r | |
830 | UINT64 Target;\r | |
831 | \r | |
c44218e5 JW |
832 | //\r |
833 | // UEFI spec requires that allocated pool must be 8-byte aligned. If it's\r | |
834 | // indicated to put the pool near the Tail Guard, we need extra bytes to\r | |
835 | // make sure alignment of the returned pool address.\r | |
836 | //\r | |
837 | if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0) {\r | |
838 | SizeRequested = ALIGN_VALUE(SizeRequested, 8);\r | |
839 | }\r | |
840 | \r | |
e63da9f0 | 841 | Target = Start + Size - SizeRequested;\r |
dd12683e JW |
842 | ASSERT (Target >= Start);\r |
843 | if (Target == 0) {\r | |
844 | return 0;\r | |
845 | }\r | |
e63da9f0 | 846 | \r |
e63da9f0 JW |
847 | if (!IsGuardPage (Start + Size)) {\r |
848 | // No Guard at tail to share. One more page is needed.\r | |
849 | Target -= EFI_PAGES_TO_SIZE (1);\r | |
850 | }\r | |
851 | \r | |
852 | // Out of range?\r | |
853 | if (Target < Start) {\r | |
854 | return 0;\r | |
855 | }\r | |
856 | \r | |
857 | // At the edge?\r | |
858 | if (Target == Start) {\r | |
859 | if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {\r | |
860 | // No enough space for a new head Guard if no Guard at head to share.\r | |
861 | return 0;\r | |
862 | }\r | |
863 | }\r | |
864 | \r | |
865 | // OK, we have enough pages for memory and its Guards. Return the End of the\r | |
866 | // free space.\r | |
867 | return Target + SizeRequested - 1;\r | |
868 | }\r | |
869 | \r | |
870 | /**\r | |
871 | Adjust the start address and number of pages to free according to Guard.\r | |
872 | \r | |
873 | The purpose of this function is to keep the shared Guard page with adjacent\r | |
874 | memory block if it's still in guard, or free it if no more sharing. Another\r | |
875 | is to reserve pages as Guard pages in partial page free situation.\r | |
876 | \r | |
877 | @param[in,out] Memory Base address of memory to free.\r | |
878 | @param[in,out] NumberOfPages Size of memory to free.\r | |
879 | \r | |
880 | @return VOID.\r | |
881 | **/\r | |
882 | VOID\r | |
883 | AdjustMemoryF (\r | |
884 | IN OUT EFI_PHYSICAL_ADDRESS *Memory,\r | |
885 | IN OUT UINTN *NumberOfPages\r | |
886 | )\r | |
887 | {\r | |
888 | EFI_PHYSICAL_ADDRESS Start;\r | |
889 | EFI_PHYSICAL_ADDRESS MemoryToTest;\r | |
890 | UINTN PagesToFree;\r | |
6cf0a677 | 891 | UINT64 GuardBitmap;\r |
e63da9f0 JW |
892 | \r |
893 | if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {\r | |
894 | return;\r | |
895 | }\r | |
896 | \r | |
897 | Start = *Memory;\r | |
898 | PagesToFree = *NumberOfPages;\r | |
899 | \r | |
900 | //\r | |
901 | // Head Guard must be one page before, if any.\r | |
902 | //\r | |
6cf0a677 JW |
903 | // MSB-> 1 0 <-LSB\r |
904 | // -------------------\r | |
905 | // Head Guard -> 0 1 -> Don't free Head Guard (shared Guard)\r | |
906 | // Head Guard -> 0 0 -> Free Head Guard either (not shared Guard)\r | |
907 | // 1 X -> Don't free first page (need a new Guard)\r | |
908 | // (it'll be turned into a Guard page later)\r | |
909 | // -------------------\r | |
910 | // Start -> -1 -2\r | |
911 | //\r | |
912 | MemoryToTest = Start - EFI_PAGES_TO_SIZE (2);\r | |
913 | GuardBitmap = GetGuardedMemoryBits (MemoryToTest, 2);\r | |
914 | if ((GuardBitmap & BIT1) == 0) {\r | |
915 | //\r | |
916 | // Head Guard exists.\r | |
917 | //\r | |
918 | if ((GuardBitmap & BIT0) == 0) {\r | |
e63da9f0 JW |
919 | //\r |
920 | // If the head Guard is not a tail Guard of adjacent memory block,\r | |
921 | // free it; otherwise, keep it.\r | |
922 | //\r | |
923 | Start -= EFI_PAGES_TO_SIZE (1);\r | |
924 | PagesToFree += 1;\r | |
925 | }\r | |
6cf0a677 | 926 | } else {\r |
e63da9f0 | 927 | //\r |
6cf0a677 JW |
928 | // No Head Guard, and pages before memory to free are still in Guard. It's a\r |
929 | // partial free case. We need to keep one page to be a tail Guard.\r | |
e63da9f0 JW |
930 | //\r |
931 | Start += EFI_PAGES_TO_SIZE (1);\r | |
932 | PagesToFree -= 1;\r | |
933 | }\r | |
934 | \r | |
935 | //\r | |
936 | // Tail Guard must be the page after this memory block to free, if any.\r | |
937 | //\r | |
6cf0a677 JW |
938 | // MSB-> 1 0 <-LSB\r |
939 | // --------------------\r | |
940 | // 1 0 <- Tail Guard -> Don't free Tail Guard (shared Guard)\r | |
941 | // 0 0 <- Tail Guard -> Free Tail Guard either (not shared Guard)\r | |
942 | // X 1 -> Don't free last page (need a new Guard)\r | |
943 | // (it'll be turned into a Guard page later)\r | |
944 | // --------------------\r | |
945 | // +1 +0 <- End\r | |
946 | //\r | |
e63da9f0 | 947 | MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);\r |
6cf0a677 JW |
948 | GuardBitmap = GetGuardedMemoryBits (MemoryToTest, 2);\r |
949 | if ((GuardBitmap & BIT0) == 0) {\r | |
950 | //\r | |
951 | // Tail Guard exists.\r | |
952 | //\r | |
953 | if ((GuardBitmap & BIT1) == 0) {\r | |
e63da9f0 JW |
954 | //\r |
955 | // If the tail Guard is not a head Guard of adjacent memory block,\r | |
956 | // free it; otherwise, keep it.\r | |
957 | //\r | |
958 | PagesToFree += 1;\r | |
959 | }\r | |
6cf0a677 | 960 | } else if (PagesToFree > 0) {\r |
e63da9f0 | 961 | //\r |
6cf0a677 JW |
962 | // No Tail Guard, and pages after memory to free are still in Guard. It's a\r |
963 | // partial free case. We need to keep one page to be a head Guard.\r | |
e63da9f0 JW |
964 | //\r |
965 | PagesToFree -= 1;\r | |
966 | }\r | |
967 | \r | |
968 | *Memory = Start;\r | |
969 | *NumberOfPages = PagesToFree;\r | |
970 | }\r | |
971 | \r | |
972 | /**\r | |
973 | Adjust the base and number of pages to really allocate according to Guard.\r | |
974 | \r | |
975 | @param[in,out] Memory Base address of free memory.\r | |
976 | @param[in,out] NumberOfPages Size of memory to allocate.\r | |
977 | \r | |
978 | @return VOID.\r | |
979 | **/\r | |
980 | VOID\r | |
981 | AdjustMemoryA (\r | |
982 | IN OUT EFI_PHYSICAL_ADDRESS *Memory,\r | |
983 | IN OUT UINTN *NumberOfPages\r | |
984 | )\r | |
985 | {\r | |
986 | //\r | |
987 | // FindFreePages() has already taken the Guard into account. It's safe to\r | |
988 | // adjust the start address and/or number of pages here, to make sure that\r | |
989 | // the Guards are also "allocated".\r | |
990 | //\r | |
991 | if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {\r | |
992 | // No tail Guard, add one.\r | |
993 | *NumberOfPages += 1;\r | |
994 | }\r | |
995 | \r | |
996 | if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {\r | |
997 | // No head Guard, add one.\r | |
998 | *Memory -= EFI_PAGE_SIZE;\r | |
999 | *NumberOfPages += 1;\r | |
1000 | }\r | |
1001 | }\r | |
1002 | \r | |
1003 | /**\r | |
1004 | Adjust the pool head position to make sure the Guard page is adjavent to\r | |
1005 | pool tail or pool head.\r | |
1006 | \r | |
1007 | @param[in] Memory Base address of memory allocated.\r | |
1008 | @param[in] NoPages Number of pages actually allocated.\r | |
1009 | @param[in] Size Size of memory requested.\r | |
1010 | (plus pool head/tail overhead)\r | |
1011 | \r | |
1012 | @return Address of pool head.\r | |
1013 | **/\r | |
1014 | VOID *\r | |
1015 | AdjustPoolHeadA (\r | |
1016 | IN EFI_PHYSICAL_ADDRESS Memory,\r | |
1017 | IN UINTN NoPages,\r | |
1018 | IN UINTN Size\r | |
1019 | )\r | |
1020 | {\r | |
c44218e5 | 1021 | if (Memory == 0 || (PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {\r |
e63da9f0 JW |
1022 | //\r |
1023 | // Pool head is put near the head Guard\r | |
1024 | //\r | |
1025 | return (VOID *)(UINTN)Memory;\r | |
1026 | }\r | |
1027 | \r | |
1028 | //\r | |
1029 | // Pool head is put near the tail Guard\r | |
1030 | //\r | |
c44218e5 | 1031 | Size = ALIGN_VALUE (Size, 8);\r |
e63da9f0 JW |
1032 | return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);\r |
1033 | }\r | |
1034 | \r | |
1035 | /**\r | |
1036 | Get the page base address according to pool head address.\r | |
1037 | \r | |
1038 | @param[in] Memory Head address of pool to free.\r | |
1039 | \r | |
1040 | @return Address of pool head.\r | |
1041 | **/\r | |
1042 | VOID *\r | |
1043 | AdjustPoolHeadF (\r | |
1044 | IN EFI_PHYSICAL_ADDRESS Memory\r | |
1045 | )\r | |
1046 | {\r | |
c44218e5 | 1047 | if (Memory == 0 || (PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {\r |
e63da9f0 JW |
1048 | //\r |
1049 | // Pool head is put near the head Guard\r | |
1050 | //\r | |
1051 | return (VOID *)(UINTN)Memory;\r | |
1052 | }\r | |
1053 | \r | |
1054 | //\r | |
1055 | // Pool head is put near the tail Guard\r | |
1056 | //\r | |
1057 | return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);\r | |
1058 | }\r | |
1059 | \r | |
1060 | /**\r | |
1061 | Allocate or free guarded memory.\r | |
1062 | \r | |
1063 | @param[in] Start Start address of memory to allocate or free.\r | |
1064 | @param[in] NumberOfPages Memory size in pages.\r | |
1065 | @param[in] NewType Memory type to convert to.\r | |
1066 | \r | |
1067 | @return VOID.\r | |
1068 | **/\r | |
1069 | EFI_STATUS\r | |
1070 | CoreConvertPagesWithGuard (\r | |
1071 | IN UINT64 Start,\r | |
1072 | IN UINTN NumberOfPages,\r | |
1073 | IN EFI_MEMORY_TYPE NewType\r | |
1074 | )\r | |
1075 | {\r | |
425d2569 JW |
1076 | UINT64 OldStart;\r |
1077 | UINTN OldPages;\r | |
1078 | \r | |
e63da9f0 | 1079 | if (NewType == EfiConventionalMemory) {\r |
425d2569 JW |
1080 | OldStart = Start;\r |
1081 | OldPages = NumberOfPages;\r | |
1082 | \r | |
e63da9f0 | 1083 | AdjustMemoryF (&Start, &NumberOfPages);\r |
425d2569 JW |
1084 | //\r |
1085 | // It's safe to unset Guard page inside memory lock because there should\r | |
1086 | // be no memory allocation occurred in updating memory page attribute at\r | |
1087 | // this point. And unsetting Guard page before free will prevent Guard\r | |
1088 | // page just freed back to pool from being allocated right away before\r | |
1089 | // marking it usable (from non-present to present).\r | |
1090 | //\r | |
1091 | UnsetGuardForMemory (OldStart, OldPages);\r | |
1263ecf2 JW |
1092 | if (NumberOfPages == 0) {\r |
1093 | return EFI_SUCCESS;\r | |
1094 | }\r | |
e63da9f0 JW |
1095 | } else {\r |
1096 | AdjustMemoryA (&Start, &NumberOfPages);\r | |
1097 | }\r | |
1098 | \r | |
6cf0a677 | 1099 | return CoreConvertPages (Start, NumberOfPages, NewType);\r |
e63da9f0 JW |
1100 | }\r |
1101 | \r | |
7fef06af JW |
1102 | /**\r |
1103 | Set all Guard pages which cannot be set before CPU Arch Protocol installed.\r | |
1104 | **/\r | |
1105 | VOID\r | |
1106 | SetAllGuardPages (\r | |
1107 | VOID\r | |
1108 | )\r | |
1109 | {\r | |
1110 | UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1111 | UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1112 | UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1113 | UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1114 | UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1115 | UINT64 TableEntry;\r | |
1116 | UINT64 Address;\r | |
1117 | UINT64 GuardPage;\r | |
1118 | INTN Level;\r | |
1119 | UINTN Index;\r | |
1120 | BOOLEAN OnGuarding;\r | |
1121 | \r | |
1122 | if (mGuardedMemoryMap == 0 ||\r | |
1123 | mMapLevel == 0 ||\r | |
1124 | mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH) {\r | |
1125 | return;\r | |
1126 | }\r | |
1127 | \r | |
1128 | CopyMem (Entries, mLevelMask, sizeof (Entries));\r | |
1129 | CopyMem (Shifts, mLevelShift, sizeof (Shifts));\r | |
1130 | \r | |
1131 | SetMem (Tables, sizeof(Tables), 0);\r | |
1132 | SetMem (Addresses, sizeof(Addresses), 0);\r | |
1133 | SetMem (Indices, sizeof(Indices), 0);\r | |
1134 | \r | |
1135 | Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r | |
1136 | Tables[Level] = mGuardedMemoryMap;\r | |
1137 | Address = 0;\r | |
1138 | OnGuarding = FALSE;\r | |
1139 | \r | |
1140 | DEBUG_CODE (\r | |
1141 | DumpGuardedMemoryBitmap ();\r | |
1142 | );\r | |
1143 | \r | |
1144 | while (TRUE) {\r | |
1145 | if (Indices[Level] > Entries[Level]) {\r | |
1146 | Tables[Level] = 0;\r | |
1147 | Level -= 1;\r | |
1148 | } else {\r | |
1149 | \r | |
1150 | TableEntry = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];\r | |
1151 | Address = Addresses[Level];\r | |
1152 | \r | |
1153 | if (TableEntry == 0) {\r | |
1154 | \r | |
1155 | OnGuarding = FALSE;\r | |
1156 | \r | |
1157 | } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {\r | |
1158 | \r | |
1159 | Level += 1;\r | |
1160 | Tables[Level] = TableEntry;\r | |
1161 | Addresses[Level] = Address;\r | |
1162 | Indices[Level] = 0;\r | |
1163 | \r | |
1164 | continue;\r | |
1165 | \r | |
1166 | } else {\r | |
1167 | \r | |
1168 | Index = 0;\r | |
1169 | while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {\r | |
1170 | if ((TableEntry & 1) == 1) {\r | |
1171 | if (OnGuarding) {\r | |
1172 | GuardPage = 0;\r | |
1173 | } else {\r | |
1174 | GuardPage = Address - EFI_PAGE_SIZE;\r | |
1175 | }\r | |
1176 | OnGuarding = TRUE;\r | |
1177 | } else {\r | |
1178 | if (OnGuarding) {\r | |
1179 | GuardPage = Address;\r | |
1180 | } else {\r | |
1181 | GuardPage = 0;\r | |
1182 | }\r | |
1183 | OnGuarding = FALSE;\r | |
1184 | }\r | |
1185 | \r | |
1186 | if (GuardPage != 0) {\r | |
1187 | SetGuardPage (GuardPage);\r | |
1188 | }\r | |
1189 | \r | |
1190 | if (TableEntry == 0) {\r | |
1191 | break;\r | |
1192 | }\r | |
1193 | \r | |
1194 | TableEntry = RShiftU64 (TableEntry, 1);\r | |
1195 | Address += EFI_PAGE_SIZE;\r | |
1196 | Index += 1;\r | |
1197 | }\r | |
1198 | }\r | |
1199 | }\r | |
1200 | \r | |
1201 | if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {\r | |
1202 | break;\r | |
1203 | }\r | |
1204 | \r | |
1205 | Indices[Level] += 1;\r | |
1206 | Address = (Level == 0) ? 0 : Addresses[Level - 1];\r | |
1207 | Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);\r | |
1208 | \r | |
1209 | }\r | |
1210 | }\r | |
1211 | \r | |
63ebde8e JW |
1212 | /**\r |
1213 | Find the address of top-most guarded free page.\r | |
1214 | \r | |
1215 | @param[out] Address Start address of top-most guarded free page.\r | |
1216 | \r | |
1217 | @return VOID.\r | |
1218 | **/\r | |
1219 | VOID\r | |
1220 | GetLastGuardedFreePageAddress (\r | |
1221 | OUT EFI_PHYSICAL_ADDRESS *Address\r | |
1222 | )\r | |
1223 | {\r | |
1224 | EFI_PHYSICAL_ADDRESS AddressGranularity;\r | |
1225 | EFI_PHYSICAL_ADDRESS BaseAddress;\r | |
1226 | UINTN Level;\r | |
1227 | UINT64 Map;\r | |
1228 | INTN Index;\r | |
1229 | \r | |
1230 | ASSERT (mMapLevel >= 1);\r | |
1231 | \r | |
1232 | BaseAddress = 0;\r | |
1233 | Map = mGuardedMemoryMap;\r | |
1234 | for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r | |
1235 | Level < GUARDED_HEAP_MAP_TABLE_DEPTH;\r | |
1236 | ++Level) {\r | |
1237 | AddressGranularity = LShiftU64 (1, mLevelShift[Level]);\r | |
1238 | \r | |
1239 | //\r | |
1240 | // Find the non-NULL entry at largest index.\r | |
1241 | //\r | |
1242 | for (Index = (INTN)mLevelMask[Level]; Index >= 0 ; --Index) {\r | |
1243 | if (((UINT64 *)(UINTN)Map)[Index] != 0) {\r | |
1244 | BaseAddress += MultU64x32 (AddressGranularity, (UINT32)Index);\r | |
1245 | Map = ((UINT64 *)(UINTN)Map)[Index];\r | |
1246 | break;\r | |
1247 | }\r | |
1248 | }\r | |
1249 | }\r | |
1250 | \r | |
1251 | //\r | |
1252 | // Find the non-zero MSB then get the page address.\r | |
1253 | //\r | |
1254 | while (Map != 0) {\r | |
1255 | Map = RShiftU64 (Map, 1);\r | |
1256 | BaseAddress += EFI_PAGES_TO_SIZE (1);\r | |
1257 | }\r | |
1258 | \r | |
1259 | *Address = BaseAddress;\r | |
1260 | }\r | |
1261 | \r | |
1262 | /**\r | |
1263 | Record freed pages.\r | |
1264 | \r | |
1265 | @param[in] BaseAddress Base address of just freed pages.\r | |
1266 | @param[in] Pages Number of freed pages.\r | |
1267 | \r | |
1268 | @return VOID.\r | |
1269 | **/\r | |
1270 | VOID\r | |
1271 | MarkFreedPages (\r | |
1272 | IN EFI_PHYSICAL_ADDRESS BaseAddress,\r | |
1273 | IN UINTN Pages\r | |
1274 | )\r | |
1275 | {\r | |
1276 | SetGuardedMemoryBits (BaseAddress, Pages);\r | |
1277 | }\r | |
1278 | \r | |
1279 | /**\r | |
1280 | Record freed pages as well as mark them as not-present.\r | |
1281 | \r | |
1282 | @param[in] BaseAddress Base address of just freed pages.\r | |
1283 | @param[in] Pages Number of freed pages.\r | |
1284 | \r | |
1285 | @return VOID.\r | |
1286 | **/\r | |
1287 | VOID\r | |
1288 | EFIAPI\r | |
1289 | GuardFreedPages (\r | |
1290 | IN EFI_PHYSICAL_ADDRESS BaseAddress,\r | |
1291 | IN UINTN Pages\r | |
1292 | )\r | |
1293 | {\r | |
1294 | EFI_STATUS Status;\r | |
1295 | \r | |
1296 | //\r | |
1297 | // Legacy memory lower than 1MB might be accessed with no allocation. Leave\r | |
1298 | // them alone.\r | |
1299 | //\r | |
1300 | if (BaseAddress < BASE_1MB) {\r | |
1301 | return;\r | |
1302 | }\r | |
1303 | \r | |
1304 | MarkFreedPages (BaseAddress, Pages);\r | |
1305 | if (gCpu != NULL) {\r | |
1306 | //\r | |
1307 | // Set flag to make sure allocating memory without GUARD for page table\r | |
1308 | // operation; otherwise infinite loops could be caused.\r | |
1309 | //\r | |
1310 | mOnGuarding = TRUE;\r | |
1311 | //\r | |
1312 | // Note: This might overwrite other attributes needed by other features,\r | |
1313 | // such as NX memory protection.\r | |
1314 | //\r | |
1315 | Status = gCpu->SetMemoryAttributes (\r | |
1316 | gCpu,\r | |
1317 | BaseAddress,\r | |
1318 | EFI_PAGES_TO_SIZE (Pages),\r | |
1319 | EFI_MEMORY_RP\r | |
1320 | );\r | |
1321 | //\r | |
1322 | // Normally we should ASSERT the returned Status. But there might be memory\r | |
1323 | // alloc/free involved in SetMemoryAttributes(), which might fail this\r | |
1324 | // calling. It's rare case so it's OK to let a few tiny holes be not-guarded.\r | |
1325 | //\r | |
1326 | if (EFI_ERROR (Status)) {\r | |
1327 | DEBUG ((DEBUG_WARN, "Failed to guard freed pages: %p (%lu)\n", BaseAddress, (UINT64)Pages));\r | |
1328 | }\r | |
1329 | mOnGuarding = FALSE;\r | |
1330 | }\r | |
1331 | }\r | |
1332 | \r | |
1333 | /**\r | |
1334 | Record freed pages as well as mark them as not-present, if enabled.\r | |
1335 | \r | |
1336 | @param[in] BaseAddress Base address of just freed pages.\r | |
1337 | @param[in] Pages Number of freed pages.\r | |
1338 | \r | |
1339 | @return VOID.\r | |
1340 | **/\r | |
1341 | VOID\r | |
1342 | EFIAPI\r | |
1343 | GuardFreedPagesChecked (\r | |
1344 | IN EFI_PHYSICAL_ADDRESS BaseAddress,\r | |
1345 | IN UINTN Pages\r | |
1346 | )\r | |
1347 | {\r | |
1348 | if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r | |
1349 | GuardFreedPages (BaseAddress, Pages);\r | |
1350 | }\r | |
1351 | }\r | |
1352 | \r | |
1353 | /**\r | |
1354 | Mark all pages freed before CPU Arch Protocol as not-present.\r | |
1355 | \r | |
1356 | **/\r | |
1357 | VOID\r | |
1358 | GuardAllFreedPages (\r | |
1359 | VOID\r | |
1360 | )\r | |
1361 | {\r | |
1362 | UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1363 | UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1364 | UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1365 | UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1366 | UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1367 | UINT64 TableEntry;\r | |
1368 | UINT64 Address;\r | |
1369 | UINT64 GuardPage;\r | |
1370 | INTN Level;\r | |
e5001ab7 | 1371 | UINT64 BitIndex;\r |
63ebde8e JW |
1372 | UINTN GuardPageNumber;\r |
1373 | \r | |
1374 | if (mGuardedMemoryMap == 0 ||\r | |
1375 | mMapLevel == 0 ||\r | |
1376 | mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH) {\r | |
1377 | return;\r | |
1378 | }\r | |
1379 | \r | |
1380 | CopyMem (Entries, mLevelMask, sizeof (Entries));\r | |
1381 | CopyMem (Shifts, mLevelShift, sizeof (Shifts));\r | |
1382 | \r | |
1383 | SetMem (Tables, sizeof(Tables), 0);\r | |
1384 | SetMem (Addresses, sizeof(Addresses), 0);\r | |
1385 | SetMem (Indices, sizeof(Indices), 0);\r | |
1386 | \r | |
1387 | Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r | |
1388 | Tables[Level] = mGuardedMemoryMap;\r | |
1389 | Address = 0;\r | |
1390 | GuardPage = (UINT64)-1;\r | |
1391 | GuardPageNumber = 0;\r | |
1392 | \r | |
1393 | while (TRUE) {\r | |
1394 | if (Indices[Level] > Entries[Level]) {\r | |
1395 | Tables[Level] = 0;\r | |
1396 | Level -= 1;\r | |
1397 | } else {\r | |
1398 | TableEntry = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];\r | |
1399 | Address = Addresses[Level];\r | |
1400 | \r | |
1401 | if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {\r | |
1402 | Level += 1;\r | |
1403 | Tables[Level] = TableEntry;\r | |
1404 | Addresses[Level] = Address;\r | |
1405 | Indices[Level] = 0;\r | |
1406 | \r | |
1407 | continue;\r | |
1408 | } else {\r | |
1409 | BitIndex = 1;\r | |
1410 | while (BitIndex != 0) {\r | |
1411 | if ((TableEntry & BitIndex) != 0) {\r | |
1412 | if (GuardPage == (UINT64)-1) {\r | |
1413 | GuardPage = Address;\r | |
1414 | }\r | |
1415 | ++GuardPageNumber;\r | |
1416 | } else if (GuardPageNumber > 0) {\r | |
1417 | GuardFreedPages (GuardPage, GuardPageNumber);\r | |
1418 | GuardPageNumber = 0;\r | |
1419 | GuardPage = (UINT64)-1;\r | |
1420 | }\r | |
1421 | \r | |
1422 | if (TableEntry == 0) {\r | |
1423 | break;\r | |
1424 | }\r | |
1425 | \r | |
1426 | Address += EFI_PAGES_TO_SIZE (1);\r | |
1427 | BitIndex = LShiftU64 (BitIndex, 1);\r | |
1428 | }\r | |
1429 | }\r | |
1430 | }\r | |
1431 | \r | |
1432 | if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {\r | |
1433 | break;\r | |
1434 | }\r | |
1435 | \r | |
1436 | Indices[Level] += 1;\r | |
1437 | Address = (Level == 0) ? 0 : Addresses[Level - 1];\r | |
1438 | Addresses[Level] = Address | LShiftU64 (Indices[Level], Shifts[Level]);\r | |
1439 | \r | |
1440 | }\r | |
1441 | \r | |
1442 | //\r | |
1443 | // Update the maximum address of freed page which can be used for memory\r | |
1444 | // promotion upon out-of-memory-space.\r | |
1445 | //\r | |
1446 | GetLastGuardedFreePageAddress (&Address);\r | |
1447 | if (Address != 0) {\r | |
1448 | mLastPromotedPage = Address;\r | |
1449 | }\r | |
1450 | }\r | |
1451 | \r | |
1452 | /**\r | |
1453 | This function checks to see if the given memory map descriptor in a memory map\r | |
1454 | can be merged with any guarded free pages.\r | |
1455 | \r | |
1456 | @param MemoryMapEntry A pointer to a descriptor in MemoryMap.\r | |
1457 | @param MaxAddress Maximum address to stop the merge.\r | |
1458 | \r | |
1459 | @return VOID\r | |
1460 | \r | |
1461 | **/\r | |
1462 | VOID\r | |
1463 | MergeGuardPages (\r | |
1464 | IN EFI_MEMORY_DESCRIPTOR *MemoryMapEntry,\r | |
1465 | IN EFI_PHYSICAL_ADDRESS MaxAddress\r | |
1466 | )\r | |
1467 | {\r | |
1468 | EFI_PHYSICAL_ADDRESS EndAddress;\r | |
1469 | UINT64 Bitmap;\r | |
1470 | INTN Pages;\r | |
1471 | \r | |
1472 | if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED) ||\r | |
1473 | MemoryMapEntry->Type >= EfiMemoryMappedIO) {\r | |
1474 | return;\r | |
1475 | }\r | |
1476 | \r | |
1477 | Bitmap = 0;\r | |
e5001ab7 JW |
1478 | Pages = EFI_SIZE_TO_PAGES ((UINTN)(MaxAddress - MemoryMapEntry->PhysicalStart));\r |
1479 | Pages -= (INTN)MemoryMapEntry->NumberOfPages;\r | |
63ebde8e JW |
1480 | while (Pages > 0) {\r |
1481 | if (Bitmap == 0) {\r | |
1482 | EndAddress = MemoryMapEntry->PhysicalStart +\r | |
e5001ab7 | 1483 | EFI_PAGES_TO_SIZE ((UINTN)MemoryMapEntry->NumberOfPages);\r |
63ebde8e JW |
1484 | Bitmap = GetGuardedMemoryBits (EndAddress, GUARDED_HEAP_MAP_ENTRY_BITS);\r |
1485 | }\r | |
1486 | \r | |
1487 | if ((Bitmap & 1) == 0) {\r | |
1488 | break;\r | |
1489 | }\r | |
1490 | \r | |
1491 | Pages--;\r | |
1492 | MemoryMapEntry->NumberOfPages++;\r | |
1493 | Bitmap = RShiftU64 (Bitmap, 1);\r | |
1494 | }\r | |
1495 | }\r | |
1496 | \r | |
1497 | /**\r | |
1498 | Put part (at most 64 pages a time) guarded free pages back to free page pool.\r | |
1499 | \r | |
1500 | Freed memory guard is used to detect Use-After-Free (UAF) memory issue, which\r | |
1501 | makes use of 'Used then throw away' way to detect any illegal access to freed\r | |
1502 | memory. The thrown-away memory will be marked as not-present so that any access\r | |
1503 | to those memory (after free) will be caught by page-fault exception.\r | |
1504 | \r | |
1505 | The problem is that this will consume lots of memory space. Once no memory\r | |
1506 | left in pool to allocate, we have to restore part of the freed pages to their\r | |
1507 | normal function. Otherwise the whole system will stop functioning.\r | |
1508 | \r | |
1509 | @param StartAddress Start address of promoted memory.\r | |
1510 | @param EndAddress End address of promoted memory.\r | |
1511 | \r | |
1512 | @return TRUE Succeeded to promote memory.\r | |
1513 | @return FALSE No free memory found.\r | |
1514 | \r | |
1515 | **/\r | |
1516 | BOOLEAN\r | |
1517 | PromoteGuardedFreePages (\r | |
1518 | OUT EFI_PHYSICAL_ADDRESS *StartAddress,\r | |
1519 | OUT EFI_PHYSICAL_ADDRESS *EndAddress\r | |
1520 | )\r | |
1521 | {\r | |
1522 | EFI_STATUS Status;\r | |
1523 | UINTN AvailablePages;\r | |
1524 | UINT64 Bitmap;\r | |
1525 | EFI_PHYSICAL_ADDRESS Start;\r | |
1526 | \r | |
1527 | if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r | |
1528 | return FALSE;\r | |
1529 | }\r | |
1530 | \r | |
1531 | //\r | |
1532 | // Similar to memory allocation service, always search the freed pages in\r | |
1533 | // descending direction.\r | |
1534 | //\r | |
1535 | Start = mLastPromotedPage;\r | |
1536 | AvailablePages = 0;\r | |
1537 | while (AvailablePages == 0) {\r | |
1538 | Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);\r | |
1539 | //\r | |
1540 | // If the address wraps around, try the really freed pages at top.\r | |
1541 | //\r | |
1542 | if (Start > mLastPromotedPage) {\r | |
1543 | GetLastGuardedFreePageAddress (&Start);\r | |
1544 | ASSERT (Start != 0);\r | |
1545 | Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);\r | |
1546 | }\r | |
1547 | \r | |
1548 | Bitmap = GetGuardedMemoryBits (Start, GUARDED_HEAP_MAP_ENTRY_BITS);\r | |
1549 | while (Bitmap > 0) {\r | |
1550 | if ((Bitmap & 1) != 0) {\r | |
1551 | ++AvailablePages;\r | |
1552 | } else if (AvailablePages == 0) {\r | |
1553 | Start += EFI_PAGES_TO_SIZE (1);\r | |
1554 | } else {\r | |
1555 | break;\r | |
1556 | }\r | |
1557 | \r | |
1558 | Bitmap = RShiftU64 (Bitmap, 1);\r | |
1559 | }\r | |
1560 | }\r | |
1561 | \r | |
1562 | if (AvailablePages) {\r | |
1563 | DEBUG ((DEBUG_INFO, "Promoted pages: %lX (%lx)\r\n", Start, (UINT64)AvailablePages));\r | |
1564 | ClearGuardedMemoryBits (Start, AvailablePages);\r | |
1565 | \r | |
1566 | if (gCpu != NULL) {\r | |
1567 | //\r | |
1568 | // Set flag to make sure allocating memory without GUARD for page table\r | |
1569 | // operation; otherwise infinite loops could be caused.\r | |
1570 | //\r | |
1571 | mOnGuarding = TRUE;\r | |
1572 | Status = gCpu->SetMemoryAttributes (gCpu, Start, EFI_PAGES_TO_SIZE(AvailablePages), 0);\r | |
1573 | ASSERT_EFI_ERROR (Status);\r | |
1574 | mOnGuarding = FALSE;\r | |
1575 | }\r | |
1576 | \r | |
1577 | mLastPromotedPage = Start;\r | |
1578 | *StartAddress = Start;\r | |
1579 | *EndAddress = Start + EFI_PAGES_TO_SIZE (AvailablePages) - 1;\r | |
1580 | return TRUE;\r | |
1581 | }\r | |
1582 | \r | |
1583 | return FALSE;\r | |
1584 | }\r | |
1585 | \r | |
7fef06af JW |
1586 | /**\r |
1587 | Notify function used to set all Guard pages before CPU Arch Protocol installed.\r | |
1588 | **/\r | |
1589 | VOID\r | |
1590 | HeapGuardCpuArchProtocolNotify (\r | |
1591 | VOID\r | |
1592 | )\r | |
1593 | {\r | |
1594 | ASSERT (gCpu != NULL);\r | |
63ebde8e JW |
1595 | \r |
1596 | if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL) &&\r | |
1597 | IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r | |
1598 | DEBUG ((DEBUG_ERROR, "Heap guard and freed memory guard cannot be enabled at the same time.\n"));\r | |
1599 | CpuDeadLoop ();\r | |
1600 | }\r | |
1601 | \r | |
1602 | if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL)) {\r | |
1603 | SetAllGuardPages ();\r | |
1604 | }\r | |
1605 | \r | |
1606 | if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r | |
1607 | GuardAllFreedPages ();\r | |
1608 | }\r | |
7fef06af JW |
1609 | }\r |
1610 | \r | |
e63da9f0 JW |
1611 | /**\r |
1612 | Helper function to convert a UINT64 value in binary to a string.\r | |
1613 | \r | |
1614 | @param[in] Value Value of a UINT64 integer.\r | |
1615 | @param[out] BinString String buffer to contain the conversion result.\r | |
1616 | \r | |
1617 | @return VOID.\r | |
1618 | **/\r | |
1619 | VOID\r | |
1620 | Uint64ToBinString (\r | |
1621 | IN UINT64 Value,\r | |
1622 | OUT CHAR8 *BinString\r | |
1623 | )\r | |
1624 | {\r | |
1625 | UINTN Index;\r | |
1626 | \r | |
1627 | if (BinString == NULL) {\r | |
1628 | return;\r | |
1629 | }\r | |
1630 | \r | |
1631 | for (Index = 64; Index > 0; --Index) {\r | |
1632 | BinString[Index - 1] = '0' + (Value & 1);\r | |
1633 | Value = RShiftU64 (Value, 1);\r | |
1634 | }\r | |
1635 | BinString[64] = '\0';\r | |
1636 | }\r | |
1637 | \r | |
1638 | /**\r | |
1639 | Dump the guarded memory bit map.\r | |
1640 | **/\r | |
1641 | VOID\r | |
1642 | EFIAPI\r | |
1643 | DumpGuardedMemoryBitmap (\r | |
1644 | VOID\r | |
1645 | )\r | |
1646 | {\r | |
1647 | UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1648 | UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1649 | UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1650 | UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1651 | UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];\r | |
1652 | UINT64 TableEntry;\r | |
1653 | UINT64 Address;\r | |
1654 | INTN Level;\r | |
1655 | UINTN RepeatZero;\r | |
1656 | CHAR8 String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];\r | |
1657 | CHAR8 *Ruler1;\r | |
1658 | CHAR8 *Ruler2;\r | |
1659 | \r | |
63ebde8e JW |
1660 | if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_ALL)) {\r |
1661 | return;\r | |
1662 | }\r | |
1663 | \r | |
c6c50165 JW |
1664 | if (mGuardedMemoryMap == 0 ||\r |
1665 | mMapLevel == 0 ||\r | |
1666 | mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH) {\r | |
e63da9f0 JW |
1667 | return;\r |
1668 | }\r | |
1669 | \r | |
1670 | Ruler1 = " 3 2 1 0";\r | |
1671 | Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";\r | |
1672 | \r | |
1673 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="\r | |
1674 | " Guarded Memory Bitmap "\r | |
1675 | "==============================\r\n"));\r | |
1676 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler1));\r | |
1677 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler2));\r | |
1678 | \r | |
1679 | CopyMem (Entries, mLevelMask, sizeof (Entries));\r | |
1680 | CopyMem (Shifts, mLevelShift, sizeof (Shifts));\r | |
1681 | \r | |
1682 | SetMem (Indices, sizeof(Indices), 0);\r | |
1683 | SetMem (Tables, sizeof(Tables), 0);\r | |
1684 | SetMem (Addresses, sizeof(Addresses), 0);\r | |
1685 | \r | |
1686 | Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r | |
1687 | Tables[Level] = mGuardedMemoryMap;\r | |
1688 | Address = 0;\r | |
1689 | RepeatZero = 0;\r | |
1690 | \r | |
1691 | while (TRUE) {\r | |
1692 | if (Indices[Level] > Entries[Level]) {\r | |
1693 | \r | |
1694 | Tables[Level] = 0;\r | |
1695 | Level -= 1;\r | |
1696 | RepeatZero = 0;\r | |
1697 | \r | |
1698 | DEBUG ((\r | |
1699 | HEAP_GUARD_DEBUG_LEVEL,\r | |
1700 | "========================================="\r | |
1701 | "=========================================\r\n"\r | |
1702 | ));\r | |
1703 | \r | |
1704 | } else {\r | |
1705 | \r | |
1706 | TableEntry = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];\r | |
1707 | Address = Addresses[Level];\r | |
1708 | \r | |
1709 | if (TableEntry == 0) {\r | |
1710 | \r | |
1711 | if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {\r | |
1712 | if (RepeatZero == 0) {\r | |
1713 | Uint64ToBinString(TableEntry, String);\r | |
1714 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));\r | |
1715 | } else if (RepeatZero == 1) {\r | |
1716 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "... : ...\r\n"));\r | |
1717 | }\r | |
1718 | RepeatZero += 1;\r | |
1719 | }\r | |
1720 | \r | |
1721 | } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {\r | |
1722 | \r | |
1723 | Level += 1;\r | |
1724 | Tables[Level] = TableEntry;\r | |
1725 | Addresses[Level] = Address;\r | |
1726 | Indices[Level] = 0;\r | |
1727 | RepeatZero = 0;\r | |
1728 | \r | |
1729 | continue;\r | |
1730 | \r | |
1731 | } else {\r | |
1732 | \r | |
1733 | RepeatZero = 0;\r | |
1734 | Uint64ToBinString(TableEntry, String);\r | |
1735 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));\r | |
1736 | \r | |
1737 | }\r | |
1738 | }\r | |
1739 | \r | |
1740 | if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {\r | |
1741 | break;\r | |
1742 | }\r | |
1743 | \r | |
1744 | Indices[Level] += 1;\r | |
1745 | Address = (Level == 0) ? 0 : Addresses[Level - 1];\r | |
1746 | Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);\r | |
1747 | \r | |
1748 | }\r | |
1749 | }\r | |
1750 | \r |