1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * 4 * Copyright (c) 2014 Samsung Electronics Co., Ltd. 5 * Author: Andrey Ryabinin <a.ryabinin@samsung.com> 6 */ 7 8#define pr_fmt(fmt) "kasan: test: " fmt 9 10#include <kunit/test.h> 11#include <linux/bitops.h> 12#include <linux/delay.h> 13#include <linux/io.h> 14#include <linux/kasan.h> 15#include <linux/kernel.h> 16#include <linux/mempool.h> 17#include <linux/mm.h> 18#include <linux/mman.h> 19#include <linux/module.h> 20#include <linux/printk.h> 21#include <linux/random.h> 22#include <linux/set_memory.h> 23#include <linux/slab.h> 24#include <linux/string.h> 25#include <linux/tracepoint.h> 26#include <linux/uaccess.h> 27#include <linux/vmalloc.h> 28#include <trace/events/printk.h> 29 30#include <asm/page.h> 31 32#include "kasan.h" 33 34#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE) 35 36static bool multishot; 37 38/* Fields set based on lines observed in the console. */ 39static struct { 40 bool report_found; 41 bool async_fault; 42} test_status; 43 44/* 45 * Some tests use these global variables to store return values from function 46 * calls that could otherwise be eliminated by the compiler as dead code. 47 */ 48void *kasan_ptr_result; 49int kasan_int_result; 50 51/* Probe for console output: obtains test_status lines of interest. */ 52static void probe_console(void *ignore, const char *buf, size_t len) 53{ 54 if (strnstr(buf, "BUG: KASAN: ", len)) 55 WRITE_ONCE(test_status.report_found, true); 56 else if (strnstr(buf, "Asynchronous fault: ", len)) 57 WRITE_ONCE(test_status.async_fault, true); 58} 59 60static int kasan_suite_init(struct kunit_suite *suite) 61{ 62 if (!kasan_enabled()) { 63 pr_err("Can't run KASAN tests with KASAN disabled"); 64 return -1; 65 } 66 67 /* Stop failing KUnit tests on KASAN reports. */ 68 kasan_kunit_test_suite_start(); 69 70 /* 71 * Temporarily enable multi-shot mode. Otherwise, KASAN would only 72 * report the first detected bug and panic the kernel if panic_on_warn 73 * is enabled. 74 */ 75 multishot = kasan_save_enable_multi_shot(); 76 77 register_trace_console(probe_console, NULL); 78 return 0; 79} 80 81static void kasan_suite_exit(struct kunit_suite *suite) 82{ 83 kasan_kunit_test_suite_end(); 84 kasan_restore_multi_shot(multishot); 85 unregister_trace_console(probe_console, NULL); 86 tracepoint_synchronize_unregister(); 87} 88 89static void kasan_test_exit(struct kunit *test) 90{ 91 KUNIT_EXPECT_FALSE(test, READ_ONCE(test_status.report_found)); 92} 93 94/** 95 * KUNIT_EXPECT_KASAN_FAIL - check that the executed expression produces a 96 * KASAN report; causes a KUnit test failure otherwise. 97 * 98 * @test: Currently executing KUnit test. 99 * @expression: Expression that must produce a KASAN report. 100 * 101 * For hardware tag-based KASAN, when a synchronous tag fault happens, tag 102 * checking is auto-disabled. When this happens, this test handler reenables 103 * tag checking. As tag checking can be only disabled or enabled per CPU, 104 * this handler disables migration (preemption). 105 * 106 * Since the compiler doesn't see that the expression can change the test_status 107 * fields, it can reorder or optimize away the accesses to those fields. 108 * Use READ/WRITE_ONCE() for the accesses and compiler barriers around the 109 * expression to prevent that. 110 * 111 * In between KUNIT_EXPECT_KASAN_FAIL checks, test_status.report_found is kept 112 * as false. This allows detecting KASAN reports that happen outside of the 113 * checks by asserting !test_status.report_found at the start of 114 * KUNIT_EXPECT_KASAN_FAIL and in kasan_test_exit. 115 */ 116#define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ 117 if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ 118 kasan_sync_fault_possible()) \ 119 migrate_disable(); \ 120 KUNIT_EXPECT_FALSE(test, READ_ONCE(test_status.report_found)); \ 121 barrier(); \ 122 expression; \ 123 barrier(); \ 124 if (kasan_async_fault_possible()) \ 125 kasan_force_async_fault(); \ 126 if (!READ_ONCE(test_status.report_found)) { \ 127 KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \ 128 "expected in \"" #expression \ 129 "\", but none occurred"); \ 130 } \ 131 if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ 132 kasan_sync_fault_possible()) { \ 133 if (READ_ONCE(test_status.report_found) && \ 134 !READ_ONCE(test_status.async_fault)) \ 135 kasan_enable_hw_tags(); \ 136 migrate_enable(); \ 137 } \ 138 WRITE_ONCE(test_status.report_found, false); \ 139 WRITE_ONCE(test_status.async_fault, false); \ 140} while (0) 141 142#define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \ 143 if (!IS_ENABLED(config)) \ 144 kunit_skip((test), "Test requires " #config "=y"); \ 145} while (0) 146 147#define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do { \ 148 if (IS_ENABLED(config)) \ 149 kunit_skip((test), "Test requires " #config "=n"); \ 150} while (0) 151 152#define KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test) do { \ 153 if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) \ 154 break; /* No compiler instrumentation. */ \ 155 if (IS_ENABLED(CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX)) \ 156 break; /* Should always be instrumented! */ \ 157 if (IS_ENABLED(CONFIG_GENERIC_ENTRY)) \ 158 kunit_skip((test), "Test requires checked mem*()"); \ 159} while (0) 160 161static void kmalloc_oob_right(struct kunit *test) 162{ 163 char *ptr; 164 size_t size = 128 - KASAN_GRANULE_SIZE - 5; 165 166 ptr = kmalloc(size, GFP_KERNEL); 167 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 168 169 OPTIMIZER_HIDE_VAR(ptr); 170 /* 171 * An unaligned access past the requested kmalloc size. 172 * Only generic KASAN can precisely detect these. 173 */ 174 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 175 KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 'x'); 176 177 /* 178 * An aligned access into the first out-of-bounds granule that falls 179 * within the aligned kmalloc object. 180 */ 181 KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + 5] = 'y'); 182 183 /* Out-of-bounds access past the aligned kmalloc object. */ 184 KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = 185 ptr[size + KASAN_GRANULE_SIZE + 5]); 186 187 kfree(ptr); 188} 189 190static void kmalloc_oob_left(struct kunit *test) 191{ 192 char *ptr; 193 size_t size = 15; 194 195 ptr = kmalloc(size, GFP_KERNEL); 196 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 197 198 OPTIMIZER_HIDE_VAR(ptr); 199 KUNIT_EXPECT_KASAN_FAIL(test, *ptr = *(ptr - 1)); 200 kfree(ptr); 201} 202 203static void kmalloc_node_oob_right(struct kunit *test) 204{ 205 char *ptr; 206 size_t size = 4096; 207 208 ptr = kmalloc_node(size, GFP_KERNEL, 0); 209 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 210 211 OPTIMIZER_HIDE_VAR(ptr); 212 KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); 213 kfree(ptr); 214} 215 216/* 217 * Check that KASAN detects an out-of-bounds access for a big object allocated 218 * via kmalloc(). But not as big as to trigger the page_alloc fallback. 219 */ 220static void kmalloc_big_oob_right(struct kunit *test) 221{ 222 char *ptr; 223 size_t size = KMALLOC_MAX_CACHE_SIZE - 256; 224 225 ptr = kmalloc(size, GFP_KERNEL); 226 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 227 228 OPTIMIZER_HIDE_VAR(ptr); 229 KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0); 230 kfree(ptr); 231} 232 233/* 234 * The kmalloc_large_* tests below use kmalloc() to allocate a memory chunk 235 * that does not fit into the largest slab cache and therefore is allocated via 236 * the page_alloc fallback. 237 */ 238 239static void kmalloc_large_oob_right(struct kunit *test) 240{ 241 char *ptr; 242 size_t size = KMALLOC_MAX_CACHE_SIZE + 10; 243 244 ptr = kmalloc(size, GFP_KERNEL); 245 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 246 247 OPTIMIZER_HIDE_VAR(ptr); 248 KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 0); 249 250 kfree(ptr); 251} 252 253static void kmalloc_large_uaf(struct kunit *test) 254{ 255 char *ptr; 256 size_t size = KMALLOC_MAX_CACHE_SIZE + 10; 257 258 ptr = kmalloc(size, GFP_KERNEL); 259 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 260 kfree(ptr); 261 262 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); 263} 264 265static void kmalloc_large_invalid_free(struct kunit *test) 266{ 267 char *ptr; 268 size_t size = KMALLOC_MAX_CACHE_SIZE + 10; 269 270 ptr = kmalloc(size, GFP_KERNEL); 271 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 272 273 KUNIT_EXPECT_KASAN_FAIL(test, kfree(ptr + 1)); 274} 275 276static void page_alloc_oob_right(struct kunit *test) 277{ 278 char *ptr; 279 struct page *pages; 280 size_t order = 4; 281 size_t size = (1UL << (PAGE_SHIFT + order)); 282 283 /* 284 * With generic KASAN page allocations have no redzones, thus 285 * out-of-bounds detection is not guaranteed. 286 * See https://bugzilla.kernel.org/show_bug.cgi?id=210503. 287 */ 288 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 289 290 pages = alloc_pages(GFP_KERNEL, order); 291 ptr = page_address(pages); 292 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 293 294 KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); 295 free_pages((unsigned long)ptr, order); 296} 297 298static void page_alloc_uaf(struct kunit *test) 299{ 300 char *ptr; 301 struct page *pages; 302 size_t order = 4; 303 304 pages = alloc_pages(GFP_KERNEL, order); 305 ptr = page_address(pages); 306 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 307 free_pages((unsigned long)ptr, order); 308 309 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); 310} 311 312static void krealloc_more_oob_helper(struct kunit *test, 313 size_t size1, size_t size2) 314{ 315 char *ptr1, *ptr2; 316 size_t middle; 317 318 KUNIT_ASSERT_LT(test, size1, size2); 319 middle = size1 + (size2 - size1) / 2; 320 321 ptr1 = kmalloc(size1, GFP_KERNEL); 322 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 323 324 ptr2 = krealloc(ptr1, size2, GFP_KERNEL); 325 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 326 327 /* Suppress -Warray-bounds warnings. */ 328 OPTIMIZER_HIDE_VAR(ptr2); 329 330 /* All offsets up to size2 must be accessible. */ 331 ptr2[size1 - 1] = 'x'; 332 ptr2[size1] = 'x'; 333 ptr2[middle] = 'x'; 334 ptr2[size2 - 1] = 'x'; 335 336 /* Generic mode is precise, so unaligned size2 must be inaccessible. */ 337 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 338 KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); 339 340 /* For all modes first aligned offset after size2 must be inaccessible. */ 341 KUNIT_EXPECT_KASAN_FAIL(test, 342 ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); 343 344 kfree(ptr2); 345} 346 347static void krealloc_less_oob_helper(struct kunit *test, 348 size_t size1, size_t size2) 349{ 350 char *ptr1, *ptr2; 351 size_t middle; 352 353 KUNIT_ASSERT_LT(test, size2, size1); 354 middle = size2 + (size1 - size2) / 2; 355 356 ptr1 = kmalloc(size1, GFP_KERNEL); 357 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 358 359 ptr2 = krealloc(ptr1, size2, GFP_KERNEL); 360 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 361 362 /* Suppress -Warray-bounds warnings. */ 363 OPTIMIZER_HIDE_VAR(ptr2); 364 365 /* Must be accessible for all modes. */ 366 ptr2[size2 - 1] = 'x'; 367 368 /* Generic mode is precise, so unaligned size2 must be inaccessible. */ 369 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 370 KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); 371 372 /* For all modes first aligned offset after size2 must be inaccessible. */ 373 KUNIT_EXPECT_KASAN_FAIL(test, 374 ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); 375 376 /* 377 * For all modes all size2, middle, and size1 should land in separate 378 * granules and thus the latter two offsets should be inaccessible. 379 */ 380 KUNIT_EXPECT_LE(test, round_up(size2, KASAN_GRANULE_SIZE), 381 round_down(middle, KASAN_GRANULE_SIZE)); 382 KUNIT_EXPECT_LE(test, round_up(middle, KASAN_GRANULE_SIZE), 383 round_down(size1, KASAN_GRANULE_SIZE)); 384 KUNIT_EXPECT_KASAN_FAIL(test, ptr2[middle] = 'x'); 385 KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1 - 1] = 'x'); 386 KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1] = 'x'); 387 388 kfree(ptr2); 389} 390 391static void krealloc_more_oob(struct kunit *test) 392{ 393 krealloc_more_oob_helper(test, 201, 235); 394} 395 396static void krealloc_less_oob(struct kunit *test) 397{ 398 krealloc_less_oob_helper(test, 235, 201); 399} 400 401static void krealloc_large_more_oob(struct kunit *test) 402{ 403 krealloc_more_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 201, 404 KMALLOC_MAX_CACHE_SIZE + 235); 405} 406 407static void krealloc_large_less_oob(struct kunit *test) 408{ 409 krealloc_less_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 235, 410 KMALLOC_MAX_CACHE_SIZE + 201); 411} 412 413/* 414 * Check that krealloc() detects a use-after-free, returns NULL, 415 * and doesn't unpoison the freed object. 416 */ 417static void krealloc_uaf(struct kunit *test) 418{ 419 char *ptr1, *ptr2; 420 int size1 = 201; 421 int size2 = 235; 422 423 ptr1 = kmalloc(size1, GFP_KERNEL); 424 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 425 kfree(ptr1); 426 427 KUNIT_EXPECT_KASAN_FAIL(test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL)); 428 KUNIT_ASSERT_NULL(test, ptr2); 429 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)ptr1); 430} 431 432static void kmalloc_oob_16(struct kunit *test) 433{ 434 struct { 435 u64 words[2]; 436 } *ptr1, *ptr2; 437 438 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 439 440 /* This test is specifically crafted for the generic mode. */ 441 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 442 443 /* RELOC_HIDE to prevent gcc from warning about short alloc */ 444 ptr1 = RELOC_HIDE(kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL), 0); 445 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 446 447 ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); 448 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 449 450 OPTIMIZER_HIDE_VAR(ptr1); 451 OPTIMIZER_HIDE_VAR(ptr2); 452 KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); 453 kfree(ptr1); 454 kfree(ptr2); 455} 456 457static void kmalloc_uaf_16(struct kunit *test) 458{ 459 struct { 460 u64 words[2]; 461 } *ptr1, *ptr2; 462 463 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 464 465 ptr1 = kmalloc(sizeof(*ptr1), GFP_KERNEL); 466 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 467 468 ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); 469 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 470 kfree(ptr2); 471 472 KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); 473 kfree(ptr1); 474} 475 476/* 477 * Note: in the memset tests below, the written range touches both valid and 478 * invalid memory. This makes sure that the instrumentation does not only check 479 * the starting address but the whole range. 480 */ 481 482static void kmalloc_oob_memset_2(struct kunit *test) 483{ 484 char *ptr; 485 size_t size = 128 - KASAN_GRANULE_SIZE; 486 size_t memset_size = 2; 487 488 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 489 490 ptr = kmalloc(size, GFP_KERNEL); 491 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 492 493 OPTIMIZER_HIDE_VAR(ptr); 494 OPTIMIZER_HIDE_VAR(size); 495 OPTIMIZER_HIDE_VAR(memset_size); 496 KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 1, 0, memset_size)); 497 kfree(ptr); 498} 499 500static void kmalloc_oob_memset_4(struct kunit *test) 501{ 502 char *ptr; 503 size_t size = 128 - KASAN_GRANULE_SIZE; 504 size_t memset_size = 4; 505 506 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 507 508 ptr = kmalloc(size, GFP_KERNEL); 509 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 510 511 OPTIMIZER_HIDE_VAR(ptr); 512 OPTIMIZER_HIDE_VAR(size); 513 OPTIMIZER_HIDE_VAR(memset_size); 514 KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 3, 0, memset_size)); 515 kfree(ptr); 516} 517 518static void kmalloc_oob_memset_8(struct kunit *test) 519{ 520 char *ptr; 521 size_t size = 128 - KASAN_GRANULE_SIZE; 522 size_t memset_size = 8; 523 524 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 525 526 ptr = kmalloc(size, GFP_KERNEL); 527 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 528 529 OPTIMIZER_HIDE_VAR(ptr); 530 OPTIMIZER_HIDE_VAR(size); 531 OPTIMIZER_HIDE_VAR(memset_size); 532 KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 7, 0, memset_size)); 533 kfree(ptr); 534} 535 536static void kmalloc_oob_memset_16(struct kunit *test) 537{ 538 char *ptr; 539 size_t size = 128 - KASAN_GRANULE_SIZE; 540 size_t memset_size = 16; 541 542 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 543 544 ptr = kmalloc(size, GFP_KERNEL); 545 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 546 547 OPTIMIZER_HIDE_VAR(ptr); 548 OPTIMIZER_HIDE_VAR(size); 549 OPTIMIZER_HIDE_VAR(memset_size); 550 KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 15, 0, memset_size)); 551 kfree(ptr); 552} 553 554static void kmalloc_oob_in_memset(struct kunit *test) 555{ 556 char *ptr; 557 size_t size = 128 - KASAN_GRANULE_SIZE; 558 559 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 560 561 ptr = kmalloc(size, GFP_KERNEL); 562 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 563 564 OPTIMIZER_HIDE_VAR(ptr); 565 OPTIMIZER_HIDE_VAR(size); 566 KUNIT_EXPECT_KASAN_FAIL(test, 567 memset(ptr, 0, size + KASAN_GRANULE_SIZE)); 568 kfree(ptr); 569} 570 571static void kmalloc_memmove_negative_size(struct kunit *test) 572{ 573 char *ptr; 574 size_t size = 64; 575 size_t invalid_size = -2; 576 577 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 578 579 /* 580 * Hardware tag-based mode doesn't check memmove for negative size. 581 * As a result, this test introduces a side-effect memory corruption, 582 * which can result in a crash. 583 */ 584 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_HW_TAGS); 585 586 ptr = kmalloc(size, GFP_KERNEL); 587 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 588 589 memset((char *)ptr, 0, 64); 590 OPTIMIZER_HIDE_VAR(ptr); 591 OPTIMIZER_HIDE_VAR(invalid_size); 592 KUNIT_EXPECT_KASAN_FAIL(test, 593 memmove((char *)ptr, (char *)ptr + 4, invalid_size)); 594 kfree(ptr); 595} 596 597static void kmalloc_memmove_invalid_size(struct kunit *test) 598{ 599 char *ptr; 600 size_t size = 64; 601 size_t invalid_size = size; 602 603 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 604 605 ptr = kmalloc(size, GFP_KERNEL); 606 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 607 608 memset((char *)ptr, 0, 64); 609 OPTIMIZER_HIDE_VAR(ptr); 610 OPTIMIZER_HIDE_VAR(invalid_size); 611 KUNIT_EXPECT_KASAN_FAIL(test, 612 memmove((char *)ptr, (char *)ptr + 4, invalid_size)); 613 kfree(ptr); 614} 615 616static void kmalloc_uaf(struct kunit *test) 617{ 618 char *ptr; 619 size_t size = 10; 620 621 ptr = kmalloc(size, GFP_KERNEL); 622 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 623 624 kfree(ptr); 625 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[8]); 626} 627 628static void kmalloc_uaf_memset(struct kunit *test) 629{ 630 char *ptr; 631 size_t size = 33; 632 633 KASAN_TEST_NEEDS_CHECKED_MEMINTRINSICS(test); 634 635 /* 636 * Only generic KASAN uses quarantine, which is required to avoid a 637 * kernel memory corruption this test causes. 638 */ 639 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 640 641 ptr = kmalloc(size, GFP_KERNEL); 642 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 643 644 kfree(ptr); 645 KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size)); 646} 647 648static void kmalloc_uaf2(struct kunit *test) 649{ 650 char *ptr1, *ptr2; 651 size_t size = 43; 652 int counter = 0; 653 654again: 655 ptr1 = kmalloc(size, GFP_KERNEL); 656 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 657 658 kfree(ptr1); 659 660 ptr2 = kmalloc(size, GFP_KERNEL); 661 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 662 663 /* 664 * For tag-based KASAN ptr1 and ptr2 tags might happen to be the same. 665 * Allow up to 16 attempts at generating different tags. 666 */ 667 if (!IS_ENABLED(CONFIG_KASAN_GENERIC) && ptr1 == ptr2 && counter++ < 16) { 668 kfree(ptr2); 669 goto again; 670 } 671 672 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[40]); 673 KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2); 674 675 kfree(ptr2); 676} 677 678/* 679 * Check that KASAN detects use-after-free when another object was allocated in 680 * the same slot. Relevant for the tag-based modes, which do not use quarantine. 681 */ 682static void kmalloc_uaf3(struct kunit *test) 683{ 684 char *ptr1, *ptr2; 685 size_t size = 100; 686 687 /* This test is specifically crafted for tag-based modes. */ 688 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 689 690 ptr1 = kmalloc(size, GFP_KERNEL); 691 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); 692 kfree(ptr1); 693 694 ptr2 = kmalloc(size, GFP_KERNEL); 695 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); 696 kfree(ptr2); 697 698 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[8]); 699} 700 701static void kasan_atomics_helper(struct kunit *test, void *unsafe, void *safe) 702{ 703 int *i_unsafe = unsafe; 704 705 KUNIT_EXPECT_KASAN_FAIL(test, READ_ONCE(*i_unsafe)); 706 KUNIT_EXPECT_KASAN_FAIL(test, WRITE_ONCE(*i_unsafe, 42)); 707 KUNIT_EXPECT_KASAN_FAIL(test, smp_load_acquire(i_unsafe)); 708 KUNIT_EXPECT_KASAN_FAIL(test, smp_store_release(i_unsafe, 42)); 709 710 KUNIT_EXPECT_KASAN_FAIL(test, atomic_read(unsafe)); 711 KUNIT_EXPECT_KASAN_FAIL(test, atomic_set(unsafe, 42)); 712 KUNIT_EXPECT_KASAN_FAIL(test, atomic_add(42, unsafe)); 713 KUNIT_EXPECT_KASAN_FAIL(test, atomic_sub(42, unsafe)); 714 KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc(unsafe)); 715 KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec(unsafe)); 716 KUNIT_EXPECT_KASAN_FAIL(test, atomic_and(42, unsafe)); 717 KUNIT_EXPECT_KASAN_FAIL(test, atomic_andnot(42, unsafe)); 718 KUNIT_EXPECT_KASAN_FAIL(test, atomic_or(42, unsafe)); 719 KUNIT_EXPECT_KASAN_FAIL(test, atomic_xor(42, unsafe)); 720 KUNIT_EXPECT_KASAN_FAIL(test, atomic_xchg(unsafe, 42)); 721 KUNIT_EXPECT_KASAN_FAIL(test, atomic_cmpxchg(unsafe, 21, 42)); 722 KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(unsafe, safe, 42)); 723 KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(safe, unsafe, 42)); 724 KUNIT_EXPECT_KASAN_FAIL(test, atomic_sub_and_test(42, unsafe)); 725 KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_and_test(unsafe)); 726 KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_and_test(unsafe)); 727 KUNIT_EXPECT_KASAN_FAIL(test, atomic_add_negative(42, unsafe)); 728 KUNIT_EXPECT_KASAN_FAIL(test, atomic_add_unless(unsafe, 21, 42)); 729 KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_not_zero(unsafe)); 730 KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_unless_negative(unsafe)); 731 KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_unless_positive(unsafe)); 732 KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_if_positive(unsafe)); 733 734 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_read(unsafe)); 735 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_set(unsafe, 42)); 736 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add(42, unsafe)); 737 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_sub(42, unsafe)); 738 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc(unsafe)); 739 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec(unsafe)); 740 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_and(42, unsafe)); 741 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_andnot(42, unsafe)); 742 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_or(42, unsafe)); 743 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_xor(42, unsafe)); 744 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_xchg(unsafe, 42)); 745 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_cmpxchg(unsafe, 21, 42)); 746 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(unsafe, safe, 42)); 747 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(safe, unsafe, 42)); 748 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_sub_and_test(42, unsafe)); 749 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_and_test(unsafe)); 750 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_and_test(unsafe)); 751 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add_negative(42, unsafe)); 752 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add_unless(unsafe, 21, 42)); 753 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_not_zero(unsafe)); 754 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_unless_negative(unsafe)); 755 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_unless_positive(unsafe)); 756 KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_if_positive(unsafe)); 757} 758 759static void kasan_atomics(struct kunit *test) 760{ 761 void *a1, *a2; 762 763 /* 764 * Just as with kasan_bitops_tags(), we allocate 48 bytes of memory such 765 * that the following 16 bytes will make up the redzone. 766 */ 767 a1 = kzalloc(48, GFP_KERNEL); 768 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, a1); 769 a2 = kzalloc(sizeof(atomic_long_t), GFP_KERNEL); 770 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, a2); 771 772 /* Use atomics to access the redzone. */ 773 kasan_atomics_helper(test, a1 + 48, a2); 774 775 kfree(a1); 776 kfree(a2); 777} 778 779static void kmalloc_double_kzfree(struct kunit *test) 780{ 781 char *ptr; 782 size_t size = 16; 783 784 ptr = kmalloc(size, GFP_KERNEL); 785 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 786 787 kfree_sensitive(ptr); 788 KUNIT_EXPECT_KASAN_FAIL(test, kfree_sensitive(ptr)); 789} 790 791/* Check that ksize() does NOT unpoison whole object. */ 792static void ksize_unpoisons_memory(struct kunit *test) 793{ 794 char *ptr; 795 size_t size = 128 - KASAN_GRANULE_SIZE - 5; 796 size_t real_size; 797 798 ptr = kmalloc(size, GFP_KERNEL); 799 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 800 801 real_size = ksize(ptr); 802 KUNIT_EXPECT_GT(test, real_size, size); 803 804 OPTIMIZER_HIDE_VAR(ptr); 805 806 /* These accesses shouldn't trigger a KASAN report. */ 807 ptr[0] = 'x'; 808 ptr[size - 1] = 'x'; 809 810 /* These must trigger a KASAN report. */ 811 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 812 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]); 813 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size + 5]); 814 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[real_size - 1]); 815 816 kfree(ptr); 817} 818 819/* 820 * Check that a use-after-free is detected by ksize() and via normal accesses 821 * after it. 822 */ 823static void ksize_uaf(struct kunit *test) 824{ 825 char *ptr; 826 int size = 128 - KASAN_GRANULE_SIZE; 827 828 ptr = kmalloc(size, GFP_KERNEL); 829 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 830 kfree(ptr); 831 832 OPTIMIZER_HIDE_VAR(ptr); 833 KUNIT_EXPECT_KASAN_FAIL(test, ksize(ptr)); 834 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); 835 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]); 836} 837 838/* 839 * The two tests below check that Generic KASAN prints auxiliary stack traces 840 * for RCU callbacks and workqueues. The reports need to be inspected manually. 841 * 842 * These tests are still enabled for other KASAN modes to make sure that all 843 * modes report bad accesses in tested scenarios. 844 */ 845 846static struct kasan_rcu_info { 847 int i; 848 struct rcu_head rcu; 849} *global_rcu_ptr; 850 851static void rcu_uaf_reclaim(struct rcu_head *rp) 852{ 853 struct kasan_rcu_info *fp = 854 container_of(rp, struct kasan_rcu_info, rcu); 855 856 kfree(fp); 857 ((volatile struct kasan_rcu_info *)fp)->i; 858} 859 860static void rcu_uaf(struct kunit *test) 861{ 862 struct kasan_rcu_info *ptr; 863 864 ptr = kmalloc(sizeof(struct kasan_rcu_info), GFP_KERNEL); 865 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 866 867 global_rcu_ptr = rcu_dereference_protected( 868 (struct kasan_rcu_info __rcu *)ptr, NULL); 869 870 KUNIT_EXPECT_KASAN_FAIL(test, 871 call_rcu(&global_rcu_ptr->rcu, rcu_uaf_reclaim); 872 rcu_barrier()); 873} 874 875static void workqueue_uaf_work(struct work_struct *work) 876{ 877 kfree(work); 878} 879 880static void workqueue_uaf(struct kunit *test) 881{ 882 struct workqueue_struct *workqueue; 883 struct work_struct *work; 884 885 workqueue = create_workqueue("kasan_workqueue_test"); 886 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, workqueue); 887 888 work = kmalloc(sizeof(struct work_struct), GFP_KERNEL); 889 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, work); 890 891 INIT_WORK(work, workqueue_uaf_work); 892 queue_work(workqueue, work); 893 destroy_workqueue(workqueue); 894 895 KUNIT_EXPECT_KASAN_FAIL(test, 896 ((volatile struct work_struct *)work)->data); 897} 898 899static void kfree_via_page(struct kunit *test) 900{ 901 char *ptr; 902 size_t size = 8; 903 struct page *page; 904 unsigned long offset; 905 906 ptr = kmalloc(size, GFP_KERNEL); 907 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 908 909 page = virt_to_page(ptr); 910 offset = offset_in_page(ptr); 911 kfree(page_address(page) + offset); 912} 913 914static void kfree_via_phys(struct kunit *test) 915{ 916 char *ptr; 917 size_t size = 8; 918 phys_addr_t phys; 919 920 ptr = kmalloc(size, GFP_KERNEL); 921 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 922 923 phys = virt_to_phys(ptr); 924 kfree(phys_to_virt(phys)); 925} 926 927static void kmem_cache_oob(struct kunit *test) 928{ 929 char *p; 930 size_t size = 200; 931 struct kmem_cache *cache; 932 933 cache = kmem_cache_create("test_cache", size, 0, 0, NULL); 934 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 935 936 p = kmem_cache_alloc(cache, GFP_KERNEL); 937 if (!p) { 938 kunit_err(test, "Allocation failed: %s\n", __func__); 939 kmem_cache_destroy(cache); 940 return; 941 } 942 943 KUNIT_EXPECT_KASAN_FAIL(test, *p = p[size + OOB_TAG_OFF]); 944 945 kmem_cache_free(cache, p); 946 kmem_cache_destroy(cache); 947} 948 949static void kmem_cache_double_free(struct kunit *test) 950{ 951 char *p; 952 size_t size = 200; 953 struct kmem_cache *cache; 954 955 cache = kmem_cache_create("test_cache", size, 0, 0, NULL); 956 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 957 958 p = kmem_cache_alloc(cache, GFP_KERNEL); 959 if (!p) { 960 kunit_err(test, "Allocation failed: %s\n", __func__); 961 kmem_cache_destroy(cache); 962 return; 963 } 964 965 kmem_cache_free(cache, p); 966 KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p)); 967 kmem_cache_destroy(cache); 968} 969 970static void kmem_cache_invalid_free(struct kunit *test) 971{ 972 char *p; 973 size_t size = 200; 974 struct kmem_cache *cache; 975 976 cache = kmem_cache_create("test_cache", size, 0, SLAB_TYPESAFE_BY_RCU, 977 NULL); 978 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 979 980 p = kmem_cache_alloc(cache, GFP_KERNEL); 981 if (!p) { 982 kunit_err(test, "Allocation failed: %s\n", __func__); 983 kmem_cache_destroy(cache); 984 return; 985 } 986 987 /* Trigger invalid free, the object doesn't get freed. */ 988 KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p + 1)); 989 990 /* 991 * Properly free the object to prevent the "Objects remaining in 992 * test_cache on __kmem_cache_shutdown" BUG failure. 993 */ 994 kmem_cache_free(cache, p); 995 996 kmem_cache_destroy(cache); 997} 998 999static void empty_cache_ctor(void *object) { } 1000 1001static void kmem_cache_double_destroy(struct kunit *test) 1002{ 1003 struct kmem_cache *cache; 1004 1005 /* Provide a constructor to prevent cache merging. */ 1006 cache = kmem_cache_create("test_cache", 200, 0, 0, empty_cache_ctor); 1007 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 1008 kmem_cache_destroy(cache); 1009 KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_destroy(cache)); 1010} 1011 1012static void kmem_cache_accounted(struct kunit *test) 1013{ 1014 int i; 1015 char *p; 1016 size_t size = 200; 1017 struct kmem_cache *cache; 1018 1019 cache = kmem_cache_create("test_cache", size, 0, SLAB_ACCOUNT, NULL); 1020 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 1021 1022 /* 1023 * Several allocations with a delay to allow for lazy per memcg kmem 1024 * cache creation. 1025 */ 1026 for (i = 0; i < 5; i++) { 1027 p = kmem_cache_alloc(cache, GFP_KERNEL); 1028 if (!p) 1029 goto free_cache; 1030 1031 kmem_cache_free(cache, p); 1032 msleep(100); 1033 } 1034 1035free_cache: 1036 kmem_cache_destroy(cache); 1037} 1038 1039static void kmem_cache_bulk(struct kunit *test) 1040{ 1041 struct kmem_cache *cache; 1042 size_t size = 200; 1043 char *p[10]; 1044 bool ret; 1045 int i; 1046 1047 cache = kmem_cache_create("test_cache", size, 0, 0, NULL); 1048 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 1049 1050 ret = kmem_cache_alloc_bulk(cache, GFP_KERNEL, ARRAY_SIZE(p), (void **)&p); 1051 if (!ret) { 1052 kunit_err(test, "Allocation failed: %s\n", __func__); 1053 kmem_cache_destroy(cache); 1054 return; 1055 } 1056 1057 for (i = 0; i < ARRAY_SIZE(p); i++) 1058 p[i][0] = p[i][size - 1] = 42; 1059 1060 kmem_cache_free_bulk(cache, ARRAY_SIZE(p), (void **)&p); 1061 kmem_cache_destroy(cache); 1062} 1063 1064static void *mempool_prepare_kmalloc(struct kunit *test, mempool_t *pool, size_t size) 1065{ 1066 int pool_size = 4; 1067 int ret; 1068 void *elem; 1069 1070 memset(pool, 0, sizeof(*pool)); 1071 ret = mempool_init_kmalloc_pool(pool, pool_size, size); 1072 KUNIT_ASSERT_EQ(test, ret, 0); 1073 1074 /* 1075 * Allocate one element to prevent mempool from freeing elements to the 1076 * underlying allocator and instead make it add them to the element 1077 * list when the tests trigger double-free and invalid-free bugs. 1078 * This allows testing KASAN annotations in add_element(). 1079 */ 1080 elem = mempool_alloc_preallocated(pool); 1081 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1082 1083 return elem; 1084} 1085 1086static struct kmem_cache *mempool_prepare_slab(struct kunit *test, mempool_t *pool, size_t size) 1087{ 1088 struct kmem_cache *cache; 1089 int pool_size = 4; 1090 int ret; 1091 1092 cache = kmem_cache_create("test_cache", size, 0, 0, NULL); 1093 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); 1094 1095 memset(pool, 0, sizeof(*pool)); 1096 ret = mempool_init_slab_pool(pool, pool_size, cache); 1097 KUNIT_ASSERT_EQ(test, ret, 0); 1098 1099 /* 1100 * Do not allocate one preallocated element, as we skip the double-free 1101 * and invalid-free tests for slab mempool for simplicity. 1102 */ 1103 1104 return cache; 1105} 1106 1107static void *mempool_prepare_page(struct kunit *test, mempool_t *pool, int order) 1108{ 1109 int pool_size = 4; 1110 int ret; 1111 void *elem; 1112 1113 memset(pool, 0, sizeof(*pool)); 1114 ret = mempool_init_page_pool(pool, pool_size, order); 1115 KUNIT_ASSERT_EQ(test, ret, 0); 1116 1117 elem = mempool_alloc_preallocated(pool); 1118 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1119 1120 return elem; 1121} 1122 1123static void mempool_oob_right_helper(struct kunit *test, mempool_t *pool, size_t size) 1124{ 1125 char *elem; 1126 1127 elem = mempool_alloc_preallocated(pool); 1128 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1129 1130 OPTIMIZER_HIDE_VAR(elem); 1131 1132 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 1133 KUNIT_EXPECT_KASAN_FAIL(test, 1134 ((volatile char *)&elem[size])[0]); 1135 else 1136 KUNIT_EXPECT_KASAN_FAIL(test, 1137 ((volatile char *)&elem[round_up(size, KASAN_GRANULE_SIZE)])[0]); 1138 1139 mempool_free(elem, pool); 1140} 1141 1142static void mempool_kmalloc_oob_right(struct kunit *test) 1143{ 1144 mempool_t pool; 1145 size_t size = 128 - KASAN_GRANULE_SIZE - 5; 1146 void *extra_elem; 1147 1148 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1149 1150 mempool_oob_right_helper(test, &pool, size); 1151 1152 mempool_free(extra_elem, &pool); 1153 mempool_exit(&pool); 1154} 1155 1156static void mempool_kmalloc_large_oob_right(struct kunit *test) 1157{ 1158 mempool_t pool; 1159 size_t size = KMALLOC_MAX_CACHE_SIZE + 1; 1160 void *extra_elem; 1161 1162 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1163 1164 mempool_oob_right_helper(test, &pool, size); 1165 1166 mempool_free(extra_elem, &pool); 1167 mempool_exit(&pool); 1168} 1169 1170static void mempool_slab_oob_right(struct kunit *test) 1171{ 1172 mempool_t pool; 1173 size_t size = 123; 1174 struct kmem_cache *cache; 1175 1176 cache = mempool_prepare_slab(test, &pool, size); 1177 1178 mempool_oob_right_helper(test, &pool, size); 1179 1180 mempool_exit(&pool); 1181 kmem_cache_destroy(cache); 1182} 1183 1184/* 1185 * Skip the out-of-bounds test for page mempool. With Generic KASAN, page 1186 * allocations have no redzones, and thus the out-of-bounds detection is not 1187 * guaranteed; see https://bugzilla.kernel.org/show_bug.cgi?id=210503. With 1188 * the tag-based KASAN modes, the neighboring allocation might have the same 1189 * tag; see https://bugzilla.kernel.org/show_bug.cgi?id=203505. 1190 */ 1191 1192static void mempool_uaf_helper(struct kunit *test, mempool_t *pool, bool page) 1193{ 1194 char *elem, *ptr; 1195 1196 elem = mempool_alloc_preallocated(pool); 1197 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1198 1199 mempool_free(elem, pool); 1200 1201 ptr = page ? page_address((struct page *)elem) : elem; 1202 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); 1203} 1204 1205static void mempool_kmalloc_uaf(struct kunit *test) 1206{ 1207 mempool_t pool; 1208 size_t size = 128; 1209 void *extra_elem; 1210 1211 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1212 1213 mempool_uaf_helper(test, &pool, false); 1214 1215 mempool_free(extra_elem, &pool); 1216 mempool_exit(&pool); 1217} 1218 1219static void mempool_kmalloc_large_uaf(struct kunit *test) 1220{ 1221 mempool_t pool; 1222 size_t size = KMALLOC_MAX_CACHE_SIZE + 1; 1223 void *extra_elem; 1224 1225 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1226 1227 mempool_uaf_helper(test, &pool, false); 1228 1229 mempool_free(extra_elem, &pool); 1230 mempool_exit(&pool); 1231} 1232 1233static void mempool_slab_uaf(struct kunit *test) 1234{ 1235 mempool_t pool; 1236 size_t size = 123; 1237 struct kmem_cache *cache; 1238 1239 cache = mempool_prepare_slab(test, &pool, size); 1240 1241 mempool_uaf_helper(test, &pool, false); 1242 1243 mempool_exit(&pool); 1244 kmem_cache_destroy(cache); 1245} 1246 1247static void mempool_page_alloc_uaf(struct kunit *test) 1248{ 1249 mempool_t pool; 1250 int order = 2; 1251 void *extra_elem; 1252 1253 extra_elem = mempool_prepare_page(test, &pool, order); 1254 1255 mempool_uaf_helper(test, &pool, true); 1256 1257 mempool_free(extra_elem, &pool); 1258 mempool_exit(&pool); 1259} 1260 1261static void mempool_double_free_helper(struct kunit *test, mempool_t *pool) 1262{ 1263 char *elem; 1264 1265 elem = mempool_alloc_preallocated(pool); 1266 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1267 1268 mempool_free(elem, pool); 1269 1270 KUNIT_EXPECT_KASAN_FAIL(test, mempool_free(elem, pool)); 1271} 1272 1273static void mempool_kmalloc_double_free(struct kunit *test) 1274{ 1275 mempool_t pool; 1276 size_t size = 128; 1277 char *extra_elem; 1278 1279 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1280 1281 mempool_double_free_helper(test, &pool); 1282 1283 mempool_free(extra_elem, &pool); 1284 mempool_exit(&pool); 1285} 1286 1287static void mempool_kmalloc_large_double_free(struct kunit *test) 1288{ 1289 mempool_t pool; 1290 size_t size = KMALLOC_MAX_CACHE_SIZE + 1; 1291 char *extra_elem; 1292 1293 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1294 1295 mempool_double_free_helper(test, &pool); 1296 1297 mempool_free(extra_elem, &pool); 1298 mempool_exit(&pool); 1299} 1300 1301static void mempool_page_alloc_double_free(struct kunit *test) 1302{ 1303 mempool_t pool; 1304 int order = 2; 1305 char *extra_elem; 1306 1307 extra_elem = mempool_prepare_page(test, &pool, order); 1308 1309 mempool_double_free_helper(test, &pool); 1310 1311 mempool_free(extra_elem, &pool); 1312 mempool_exit(&pool); 1313} 1314 1315static void mempool_kmalloc_invalid_free_helper(struct kunit *test, mempool_t *pool) 1316{ 1317 char *elem; 1318 1319 elem = mempool_alloc_preallocated(pool); 1320 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elem); 1321 1322 KUNIT_EXPECT_KASAN_FAIL(test, mempool_free(elem + 1, pool)); 1323 1324 mempool_free(elem, pool); 1325} 1326 1327static void mempool_kmalloc_invalid_free(struct kunit *test) 1328{ 1329 mempool_t pool; 1330 size_t size = 128; 1331 char *extra_elem; 1332 1333 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1334 1335 mempool_kmalloc_invalid_free_helper(test, &pool); 1336 1337 mempool_free(extra_elem, &pool); 1338 mempool_exit(&pool); 1339} 1340 1341static void mempool_kmalloc_large_invalid_free(struct kunit *test) 1342{ 1343 mempool_t pool; 1344 size_t size = KMALLOC_MAX_CACHE_SIZE + 1; 1345 char *extra_elem; 1346 1347 extra_elem = mempool_prepare_kmalloc(test, &pool, size); 1348 1349 mempool_kmalloc_invalid_free_helper(test, &pool); 1350 1351 mempool_free(extra_elem, &pool); 1352 mempool_exit(&pool); 1353} 1354 1355/* 1356 * Skip the invalid-free test for page mempool. The invalid-free detection only 1357 * works for compound pages and mempool preallocates all page elements without 1358 * the __GFP_COMP flag. 1359 */ 1360 1361static char global_array[10]; 1362 1363static void kasan_global_oob_right(struct kunit *test) 1364{ 1365 /* 1366 * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS 1367 * from failing here and panicking the kernel, access the array via a 1368 * volatile pointer, which will prevent the compiler from being able to 1369 * determine the array bounds. 1370 * 1371 * This access uses a volatile pointer to char (char *volatile) rather 1372 * than the more conventional pointer to volatile char (volatile char *) 1373 * because we want to prevent the compiler from making inferences about 1374 * the pointer itself (i.e. its array bounds), not the data that it 1375 * refers to. 1376 */ 1377 char *volatile array = global_array; 1378 char *p = &array[ARRAY_SIZE(global_array) + 3]; 1379 1380 /* Only generic mode instruments globals. */ 1381 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 1382 1383 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); 1384} 1385 1386static void kasan_global_oob_left(struct kunit *test) 1387{ 1388 char *volatile array = global_array; 1389 char *p = array - 3; 1390 1391 /* 1392 * GCC is known to fail this test, skip it. 1393 * See https://bugzilla.kernel.org/show_bug.cgi?id=215051. 1394 */ 1395 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_CC_IS_CLANG); 1396 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 1397 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); 1398} 1399 1400static void kasan_stack_oob(struct kunit *test) 1401{ 1402 char stack_array[10]; 1403 /* See comment in kasan_global_oob_right. */ 1404 char *volatile array = stack_array; 1405 char *p = &array[ARRAY_SIZE(stack_array) + OOB_TAG_OFF]; 1406 1407 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); 1408 1409 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); 1410} 1411 1412static void kasan_alloca_oob_left(struct kunit *test) 1413{ 1414 volatile int i = 10; 1415 char alloca_array[i]; 1416 /* See comment in kasan_global_oob_right. */ 1417 char *volatile array = alloca_array; 1418 char *p = array - 1; 1419 1420 /* Only generic mode instruments dynamic allocas. */ 1421 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 1422 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); 1423 1424 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); 1425} 1426 1427static void kasan_alloca_oob_right(struct kunit *test) 1428{ 1429 volatile int i = 10; 1430 char alloca_array[i]; 1431 /* See comment in kasan_global_oob_right. */ 1432 char *volatile array = alloca_array; 1433 char *p = array + i; 1434 1435 /* Only generic mode instruments dynamic allocas. */ 1436 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 1437 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); 1438 1439 KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); 1440} 1441 1442static void kasan_memchr(struct kunit *test) 1443{ 1444 char *ptr; 1445 size_t size = 24; 1446 1447 /* 1448 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. 1449 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. 1450 */ 1451 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); 1452 1453 if (OOB_TAG_OFF) 1454 size = round_up(size, OOB_TAG_OFF); 1455 1456 ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); 1457 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1458 1459 OPTIMIZER_HIDE_VAR(ptr); 1460 OPTIMIZER_HIDE_VAR(size); 1461 KUNIT_EXPECT_KASAN_FAIL(test, 1462 kasan_ptr_result = memchr(ptr, '1', size + 1)); 1463 1464 kfree(ptr); 1465} 1466 1467static void kasan_memcmp(struct kunit *test) 1468{ 1469 char *ptr; 1470 size_t size = 24; 1471 int arr[9]; 1472 1473 /* 1474 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. 1475 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. 1476 */ 1477 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); 1478 1479 if (OOB_TAG_OFF) 1480 size = round_up(size, OOB_TAG_OFF); 1481 1482 ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); 1483 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1484 memset(arr, 0, sizeof(arr)); 1485 1486 OPTIMIZER_HIDE_VAR(ptr); 1487 OPTIMIZER_HIDE_VAR(size); 1488 KUNIT_EXPECT_KASAN_FAIL(test, 1489 kasan_int_result = memcmp(ptr, arr, size+1)); 1490 kfree(ptr); 1491} 1492 1493static void kasan_strings(struct kunit *test) 1494{ 1495 char *ptr; 1496 size_t size = 24; 1497 1498 /* 1499 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. 1500 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. 1501 */ 1502 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); 1503 1504 ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); 1505 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1506 1507 kfree(ptr); 1508 1509 /* 1510 * Try to cause only 1 invalid access (less spam in dmesg). 1511 * For that we need ptr to point to zeroed byte. 1512 * Skip metadata that could be stored in freed object so ptr 1513 * will likely point to zeroed byte. 1514 */ 1515 ptr += 16; 1516 KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strchr(ptr, '1')); 1517 1518 KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strrchr(ptr, '1')); 1519 1520 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strcmp(ptr, "2")); 1521 1522 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strncmp(ptr, "2", 1)); 1523 1524 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strlen(ptr)); 1525 1526 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strnlen(ptr, 1)); 1527} 1528 1529static void kasan_bitops_modify(struct kunit *test, int nr, void *addr) 1530{ 1531 KUNIT_EXPECT_KASAN_FAIL(test, set_bit(nr, addr)); 1532 KUNIT_EXPECT_KASAN_FAIL(test, __set_bit(nr, addr)); 1533 KUNIT_EXPECT_KASAN_FAIL(test, clear_bit(nr, addr)); 1534 KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit(nr, addr)); 1535 KUNIT_EXPECT_KASAN_FAIL(test, clear_bit_unlock(nr, addr)); 1536 KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit_unlock(nr, addr)); 1537 KUNIT_EXPECT_KASAN_FAIL(test, change_bit(nr, addr)); 1538 KUNIT_EXPECT_KASAN_FAIL(test, __change_bit(nr, addr)); 1539} 1540 1541static void kasan_bitops_test_and_modify(struct kunit *test, int nr, void *addr) 1542{ 1543 KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit(nr, addr)); 1544 KUNIT_EXPECT_KASAN_FAIL(test, __test_and_set_bit(nr, addr)); 1545 KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(nr, addr)); 1546 KUNIT_EXPECT_KASAN_FAIL(test, test_and_clear_bit(nr, addr)); 1547 KUNIT_EXPECT_KASAN_FAIL(test, __test_and_clear_bit(nr, addr)); 1548 KUNIT_EXPECT_KASAN_FAIL(test, test_and_change_bit(nr, addr)); 1549 KUNIT_EXPECT_KASAN_FAIL(test, __test_and_change_bit(nr, addr)); 1550 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = test_bit(nr, addr)); 1551 if (nr < 7) 1552 KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = 1553 xor_unlock_is_negative_byte(1 << nr, addr)); 1554} 1555 1556static void kasan_bitops_generic(struct kunit *test) 1557{ 1558 long *bits; 1559 1560 /* This test is specifically crafted for the generic mode. */ 1561 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); 1562 1563 /* 1564 * Allocate 1 more byte, which causes kzalloc to round up to 16 bytes; 1565 * this way we do not actually corrupt other memory. 1566 */ 1567 bits = kzalloc(sizeof(*bits) + 1, GFP_KERNEL); 1568 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits); 1569 1570 /* 1571 * Below calls try to access bit within allocated memory; however, the 1572 * below accesses are still out-of-bounds, since bitops are defined to 1573 * operate on the whole long the bit is in. 1574 */ 1575 kasan_bitops_modify(test, BITS_PER_LONG, bits); 1576 1577 /* 1578 * Below calls try to access bit beyond allocated memory. 1579 */ 1580 kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, bits); 1581 1582 kfree(bits); 1583} 1584 1585static void kasan_bitops_tags(struct kunit *test) 1586{ 1587 long *bits; 1588 1589 /* This test is specifically crafted for tag-based modes. */ 1590 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 1591 1592 /* kmalloc-64 cache will be used and the last 16 bytes will be the redzone. */ 1593 bits = kzalloc(48, GFP_KERNEL); 1594 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits); 1595 1596 /* Do the accesses past the 48 allocated bytes, but within the redone. */ 1597 kasan_bitops_modify(test, BITS_PER_LONG, (void *)bits + 48); 1598 kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, (void *)bits + 48); 1599 1600 kfree(bits); 1601} 1602 1603static void vmalloc_helpers_tags(struct kunit *test) 1604{ 1605 void *ptr; 1606 1607 /* This test is intended for tag-based modes. */ 1608 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 1609 1610 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); 1611 1612 if (!kasan_vmalloc_enabled()) 1613 kunit_skip(test, "Test requires kasan.vmalloc=on"); 1614 1615 ptr = vmalloc(PAGE_SIZE); 1616 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1617 1618 /* Check that the returned pointer is tagged. */ 1619 KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); 1620 KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); 1621 1622 /* Make sure exported vmalloc helpers handle tagged pointers. */ 1623 KUNIT_ASSERT_TRUE(test, is_vmalloc_addr(ptr)); 1624 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vmalloc_to_page(ptr)); 1625 1626#if !IS_MODULE(CONFIG_KASAN_KUNIT_TEST) 1627 { 1628 int rv; 1629 1630 /* Make sure vmalloc'ed memory permissions can be changed. */ 1631 rv = set_memory_ro((unsigned long)ptr, 1); 1632 KUNIT_ASSERT_GE(test, rv, 0); 1633 rv = set_memory_rw((unsigned long)ptr, 1); 1634 KUNIT_ASSERT_GE(test, rv, 0); 1635 } 1636#endif 1637 1638 vfree(ptr); 1639} 1640 1641static void vmalloc_oob(struct kunit *test) 1642{ 1643 char *v_ptr, *p_ptr; 1644 struct page *page; 1645 size_t size = PAGE_SIZE / 2 - KASAN_GRANULE_SIZE - 5; 1646 1647 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); 1648 1649 if (!kasan_vmalloc_enabled()) 1650 kunit_skip(test, "Test requires kasan.vmalloc=on"); 1651 1652 v_ptr = vmalloc(size); 1653 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); 1654 1655 OPTIMIZER_HIDE_VAR(v_ptr); 1656 1657 /* 1658 * We have to be careful not to hit the guard page in vmalloc tests. 1659 * The MMU will catch that and crash us. 1660 */ 1661 1662 /* Make sure in-bounds accesses are valid. */ 1663 v_ptr[0] = 0; 1664 v_ptr[size - 1] = 0; 1665 1666 /* 1667 * An unaligned access past the requested vmalloc size. 1668 * Only generic KASAN can precisely detect these. 1669 */ 1670 if (IS_ENABLED(CONFIG_KASAN_GENERIC)) 1671 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size]); 1672 1673 /* An aligned access into the first out-of-bounds granule. */ 1674 KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size + 5]); 1675 1676 /* Check that in-bounds accesses to the physical page are valid. */ 1677 page = vmalloc_to_page(v_ptr); 1678 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); 1679 p_ptr = page_address(page); 1680 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); 1681 p_ptr[0] = 0; 1682 1683 vfree(v_ptr); 1684 1685 /* 1686 * We can't check for use-after-unmap bugs in this nor in the following 1687 * vmalloc tests, as the page might be fully unmapped and accessing it 1688 * will crash the kernel. 1689 */ 1690} 1691 1692static void vmap_tags(struct kunit *test) 1693{ 1694 char *p_ptr, *v_ptr; 1695 struct page *p_page, *v_page; 1696 1697 /* 1698 * This test is specifically crafted for the software tag-based mode, 1699 * the only tag-based mode that poisons vmap mappings. 1700 */ 1701 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); 1702 1703 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); 1704 1705 if (!kasan_vmalloc_enabled()) 1706 kunit_skip(test, "Test requires kasan.vmalloc=on"); 1707 1708 p_page = alloc_pages(GFP_KERNEL, 1); 1709 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_page); 1710 p_ptr = page_address(p_page); 1711 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); 1712 1713 v_ptr = vmap(&p_page, 1, VM_MAP, PAGE_KERNEL); 1714 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); 1715 1716 /* 1717 * We can't check for out-of-bounds bugs in this nor in the following 1718 * vmalloc tests, as allocations have page granularity and accessing 1719 * the guard page will crash the kernel. 1720 */ 1721 1722 KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); 1723 KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); 1724 1725 /* Make sure that in-bounds accesses through both pointers work. */ 1726 *p_ptr = 0; 1727 *v_ptr = 0; 1728 1729 /* Make sure vmalloc_to_page() correctly recovers the page pointer. */ 1730 v_page = vmalloc_to_page(v_ptr); 1731 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_page); 1732 KUNIT_EXPECT_PTR_EQ(test, p_page, v_page); 1733 1734 vunmap(v_ptr); 1735 free_pages((unsigned long)p_ptr, 1); 1736} 1737 1738static void vm_map_ram_tags(struct kunit *test) 1739{ 1740 char *p_ptr, *v_ptr; 1741 struct page *page; 1742 1743 /* 1744 * This test is specifically crafted for the software tag-based mode, 1745 * the only tag-based mode that poisons vm_map_ram mappings. 1746 */ 1747 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); 1748 1749 page = alloc_pages(GFP_KERNEL, 1); 1750 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); 1751 p_ptr = page_address(page); 1752 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); 1753 1754 v_ptr = vm_map_ram(&page, 1, -1); 1755 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); 1756 1757 KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); 1758 KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); 1759 1760 /* Make sure that in-bounds accesses through both pointers work. */ 1761 *p_ptr = 0; 1762 *v_ptr = 0; 1763 1764 vm_unmap_ram(v_ptr, 1); 1765 free_pages((unsigned long)p_ptr, 1); 1766} 1767 1768static void vmalloc_percpu(struct kunit *test) 1769{ 1770 char __percpu *ptr; 1771 int cpu; 1772 1773 /* 1774 * This test is specifically crafted for the software tag-based mode, 1775 * the only tag-based mode that poisons percpu mappings. 1776 */ 1777 KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); 1778 1779 ptr = __alloc_percpu(PAGE_SIZE, PAGE_SIZE); 1780 1781 for_each_possible_cpu(cpu) { 1782 char *c_ptr = per_cpu_ptr(ptr, cpu); 1783 1784 KUNIT_EXPECT_GE(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_MIN); 1785 KUNIT_EXPECT_LT(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_KERNEL); 1786 1787 /* Make sure that in-bounds accesses don't crash the kernel. */ 1788 *c_ptr = 0; 1789 } 1790 1791 free_percpu(ptr); 1792} 1793 1794/* 1795 * Check that the assigned pointer tag falls within the [KASAN_TAG_MIN, 1796 * KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based 1797 * modes. 1798 */ 1799static void match_all_not_assigned(struct kunit *test) 1800{ 1801 char *ptr; 1802 struct page *pages; 1803 int i, size, order; 1804 1805 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 1806 1807 for (i = 0; i < 256; i++) { 1808 size = get_random_u32_inclusive(1, 1024); 1809 ptr = kmalloc(size, GFP_KERNEL); 1810 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1811 KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); 1812 KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); 1813 kfree(ptr); 1814 } 1815 1816 for (i = 0; i < 256; i++) { 1817 order = get_random_u32_inclusive(1, 4); 1818 pages = alloc_pages(GFP_KERNEL, order); 1819 ptr = page_address(pages); 1820 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1821 KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); 1822 KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); 1823 free_pages((unsigned long)ptr, order); 1824 } 1825 1826 if (!kasan_vmalloc_enabled()) 1827 return; 1828 1829 for (i = 0; i < 256; i++) { 1830 size = get_random_u32_inclusive(1, 1024); 1831 ptr = vmalloc(size); 1832 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1833 KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); 1834 KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); 1835 vfree(ptr); 1836 } 1837} 1838 1839/* Check that 0xff works as a match-all pointer tag for tag-based modes. */ 1840static void match_all_ptr_tag(struct kunit *test) 1841{ 1842 char *ptr; 1843 u8 tag; 1844 1845 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 1846 1847 ptr = kmalloc(128, GFP_KERNEL); 1848 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1849 1850 /* Backup the assigned tag. */ 1851 tag = get_tag(ptr); 1852 KUNIT_EXPECT_NE(test, tag, (u8)KASAN_TAG_KERNEL); 1853 1854 /* Reset the tag to 0xff.*/ 1855 ptr = set_tag(ptr, KASAN_TAG_KERNEL); 1856 1857 /* This access shouldn't trigger a KASAN report. */ 1858 *ptr = 0; 1859 1860 /* Recover the pointer tag and free. */ 1861 ptr = set_tag(ptr, tag); 1862 kfree(ptr); 1863} 1864 1865/* Check that there are no match-all memory tags for tag-based modes. */ 1866static void match_all_mem_tag(struct kunit *test) 1867{ 1868 char *ptr; 1869 int tag; 1870 1871 KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); 1872 1873 ptr = kmalloc(128, GFP_KERNEL); 1874 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); 1875 KUNIT_EXPECT_NE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); 1876 1877 /* For each possible tag value not matching the pointer tag. */ 1878 for (tag = KASAN_TAG_MIN; tag <= KASAN_TAG_KERNEL; tag++) { 1879 /* 1880 * For Software Tag-Based KASAN, skip the majority of tag 1881 * values to avoid the test printing too many reports. 1882 */ 1883 if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) && 1884 tag >= KASAN_TAG_MIN + 8 && tag <= KASAN_TAG_KERNEL - 8) 1885 continue; 1886 1887 if (tag == get_tag(ptr)) 1888 continue; 1889 1890 /* Mark the first memory granule with the chosen memory tag. */ 1891 kasan_poison(ptr, KASAN_GRANULE_SIZE, (u8)tag, false); 1892 1893 /* This access must cause a KASAN report. */ 1894 KUNIT_EXPECT_KASAN_FAIL(test, *ptr = 0); 1895 } 1896 1897 /* Recover the memory tag and free. */ 1898 kasan_poison(ptr, KASAN_GRANULE_SIZE, get_tag(ptr), false); 1899 kfree(ptr); 1900} 1901 1902static struct kunit_case kasan_kunit_test_cases[] = { 1903 KUNIT_CASE(kmalloc_oob_right), 1904 KUNIT_CASE(kmalloc_oob_left), 1905 KUNIT_CASE(kmalloc_node_oob_right), 1906 KUNIT_CASE(kmalloc_big_oob_right), 1907 KUNIT_CASE(kmalloc_large_oob_right), 1908 KUNIT_CASE(kmalloc_large_uaf), 1909 KUNIT_CASE(kmalloc_large_invalid_free), 1910 KUNIT_CASE(page_alloc_oob_right), 1911 KUNIT_CASE(page_alloc_uaf), 1912 KUNIT_CASE(krealloc_more_oob), 1913 KUNIT_CASE(krealloc_less_oob), 1914 KUNIT_CASE(krealloc_large_more_oob), 1915 KUNIT_CASE(krealloc_large_less_oob), 1916 KUNIT_CASE(krealloc_uaf), 1917 KUNIT_CASE(kmalloc_oob_16), 1918 KUNIT_CASE(kmalloc_uaf_16), 1919 KUNIT_CASE(kmalloc_oob_in_memset), 1920 KUNIT_CASE(kmalloc_oob_memset_2), 1921 KUNIT_CASE(kmalloc_oob_memset_4), 1922 KUNIT_CASE(kmalloc_oob_memset_8), 1923 KUNIT_CASE(kmalloc_oob_memset_16), 1924 KUNIT_CASE(kmalloc_memmove_negative_size), 1925 KUNIT_CASE(kmalloc_memmove_invalid_size), 1926 KUNIT_CASE(kmalloc_uaf), 1927 KUNIT_CASE(kmalloc_uaf_memset), 1928 KUNIT_CASE(kmalloc_uaf2), 1929 KUNIT_CASE(kmalloc_uaf3), 1930 KUNIT_CASE(kmalloc_double_kzfree), 1931 KUNIT_CASE(ksize_unpoisons_memory), 1932 KUNIT_CASE(ksize_uaf), 1933 KUNIT_CASE(rcu_uaf), 1934 KUNIT_CASE(workqueue_uaf), 1935 KUNIT_CASE(kfree_via_page), 1936 KUNIT_CASE(kfree_via_phys), 1937 KUNIT_CASE(kmem_cache_oob), 1938 KUNIT_CASE(kmem_cache_double_free), 1939 KUNIT_CASE(kmem_cache_invalid_free), 1940 KUNIT_CASE(kmem_cache_double_destroy), 1941 KUNIT_CASE(kmem_cache_accounted), 1942 KUNIT_CASE(kmem_cache_bulk), 1943 KUNIT_CASE(mempool_kmalloc_oob_right), 1944 KUNIT_CASE(mempool_kmalloc_large_oob_right), 1945 KUNIT_CASE(mempool_slab_oob_right), 1946 KUNIT_CASE(mempool_kmalloc_uaf), 1947 KUNIT_CASE(mempool_kmalloc_large_uaf), 1948 KUNIT_CASE(mempool_slab_uaf), 1949 KUNIT_CASE(mempool_page_alloc_uaf), 1950 KUNIT_CASE(mempool_kmalloc_double_free), 1951 KUNIT_CASE(mempool_kmalloc_large_double_free), 1952 KUNIT_CASE(mempool_page_alloc_double_free), 1953 KUNIT_CASE(mempool_kmalloc_invalid_free), 1954 KUNIT_CASE(mempool_kmalloc_large_invalid_free), 1955 KUNIT_CASE(kasan_global_oob_right), 1956 KUNIT_CASE(kasan_global_oob_left), 1957 KUNIT_CASE(kasan_stack_oob), 1958 KUNIT_CASE(kasan_alloca_oob_left), 1959 KUNIT_CASE(kasan_alloca_oob_right), 1960 KUNIT_CASE(kasan_memchr), 1961 KUNIT_CASE(kasan_memcmp), 1962 KUNIT_CASE(kasan_strings), 1963 KUNIT_CASE(kasan_bitops_generic), 1964 KUNIT_CASE(kasan_bitops_tags), 1965 KUNIT_CASE(kasan_atomics), 1966 KUNIT_CASE(vmalloc_helpers_tags), 1967 KUNIT_CASE(vmalloc_oob), 1968 KUNIT_CASE(vmap_tags), 1969 KUNIT_CASE(vm_map_ram_tags), 1970 KUNIT_CASE(vmalloc_percpu), 1971 KUNIT_CASE(match_all_not_assigned), 1972 KUNIT_CASE(match_all_ptr_tag), 1973 KUNIT_CASE(match_all_mem_tag), 1974 {} 1975}; 1976 1977static struct kunit_suite kasan_kunit_test_suite = { 1978 .name = "kasan", 1979 .test_cases = kasan_kunit_test_cases, 1980 .exit = kasan_test_exit, 1981 .suite_init = kasan_suite_init, 1982 .suite_exit = kasan_suite_exit, 1983}; 1984 1985kunit_test_suite(kasan_kunit_test_suite); 1986 1987MODULE_LICENSE("GPL"); 1988