asan_poisoning.cc revision 2e9ffcbc2184f308881fc04ce0799c557b7e5b0f
1e5f5895bda30f374b0b51412fd4d837fa59aed66Alexey Samsonov//===-- asan_poisoning.cc -------------------------------------------------===// 21e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 31e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// The LLVM Compiler Infrastructure 41e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 51e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// This file is distributed under the University of Illinois Open Source 61e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// License. See LICENSE.TXT for details. 71e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 81e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany//===----------------------------------------------------------------------===// 91e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 101e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// This file is a part of AddressSanitizer, an address sanity checker. 111e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 12218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany// Shadow memory poisoning by ASan RTL and by user application. 131e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany//===----------------------------------------------------------------------===// 141e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 157e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov#include "asan_poisoning.h" 16eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany#include "sanitizer_common/sanitizer_libc.h" 171e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 181e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryanynamespace __asan { 191e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 20ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryanyvoid PoisonShadow(uptr addr, uptr size, u8 value) { 2173bad81febb2a872627c03e579beea1da4b49294Kostya Serebryany if (!flags()->poison_heap) return; 22218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany CHECK(AddrIsAlignedByGranularity(addr)); 237e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov CHECK(AddrIsInMem(addr)); 24218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany CHECK(AddrIsAlignedByGranularity(addr + size)); 257e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov CHECK(AddrIsInMem(addr + size - SHADOW_GRANULARITY)); 26a27bdf70ca24202dce21cf7c1a387aeaa400d889Kostya Serebryany CHECK(REAL(memset)); 277e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov FastPoisonShadow(addr, size, value); 28218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany} 29218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany 303f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryanyvoid PoisonShadowPartialRightRedzone(uptr addr, 313f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr size, 323f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr redzone_size, 33ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany u8 value) { 3473bad81febb2a872627c03e579beea1da4b49294Kostya Serebryany if (!flags()->poison_heap) return; 35218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany CHECK(AddrIsAlignedByGranularity(addr)); 367e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov CHECK(AddrIsInMem(addr)); 377e8434940a1fe7dce531d4c458ccd714da48f609Alexey Samsonov FastPoisonShadowPartialRightRedzone(addr, size, redzone_size, value); 38218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany} 39218a9b70d7338cf5b727b7dad6b080ad7869c6c2Kostya Serebryany 401e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryanystruct ShadowSegmentEndpoint { 41ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany u8 *chunk; 42ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany s8 offset; // in [0, SHADOW_GRANULARITY) 43ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany s8 value; // = *chunk; 441e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 453f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany explicit ShadowSegmentEndpoint(uptr address) { 46ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany chunk = (u8*)MemToShadow(address); 471e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany offset = address & (SHADOW_GRANULARITY - 1); 481e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany value = *chunk; 491e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 501e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany}; 511e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 521e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany} // namespace __asan 531e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 541e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// ---------------------- Interface ---------------- {{{1 551e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryanyusing namespace __asan; // NOLINT 561e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 571e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// Current implementation of __asan_(un)poison_memory_region doesn't check 581e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// that user program (un)poisons the memory it owns. It poisons memory 591e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// conservatively, and unpoisons progressively to make sure asan shadow 601e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// mapping invariant is preserved (see detailed mapping description here: 611e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// http://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm). 621e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// 631e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// * if user asks to poison region [left, right), the program poisons 641e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// at least [left, AlignDown(right)). 651e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// * if user asks to unpoison region [left, right), the program unpoisons 661e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany// at most [AlignDown(left), right). 679aead37421a6e4bf43265e5195c6ac31fc519982Kostya Serebryanyvoid __asan_poison_memory_region(void const volatile *addr, uptr size) { 68cb8c4dce691097718d5af41b36899b72ef4b1d84Alexey Samsonov if (!flags()->allow_user_poisoning || size == 0) return; 693f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr beg_addr = (uptr)addr; 703f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr end_addr = beg_addr + size; 71cb8c4dce691097718d5af41b36899b72ef4b1d84Alexey Samsonov if (flags()->verbosity >= 1) { 725bcca4e33ececdddd8e9e07619c129e870492251Alexey Samsonov Printf("Trying to poison memory region [%p, %p)\n", 735bcca4e33ececdddd8e9e07619c129e870492251Alexey Samsonov (void*)beg_addr, (void*)end_addr); 741e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 751e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany ShadowSegmentEndpoint beg(beg_addr); 761e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany ShadowSegmentEndpoint end(end_addr); 771e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.chunk == end.chunk) { 781e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(beg.offset < end.offset); 79ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany s8 value = beg.value; 801e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(value == end.value); 811e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // We can only poison memory if the byte in end.offset is unaddressable. 821e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // No need to re-poison memory if it is poisoned already. 831e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (value > 0 && value <= end.offset) { 841e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.offset > 0) { 852d8b3bdb112ebb8ed3f15ee41d4cebcd683b41b0Kostya Serebryany *beg.chunk = Min(value, beg.offset); 861e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } else { 871e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany *beg.chunk = kAsanUserPoisonedMemoryMagic; 881e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 891e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 901e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany return; 911e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 921e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(beg.chunk < end.chunk); 931e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.offset > 0) { 941e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // Mark bytes from beg.offset as unaddressable. 951e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.value == 0) { 961e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany *beg.chunk = beg.offset; 971e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } else { 982d8b3bdb112ebb8ed3f15ee41d4cebcd683b41b0Kostya Serebryany *beg.chunk = Min(beg.value, beg.offset); 991e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1001e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany beg.chunk++; 1011e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 10209672caefb5694f1981a1712fdefa44840a95e67Alexey Samsonov REAL(memset)(beg.chunk, kAsanUserPoisonedMemoryMagic, end.chunk - beg.chunk); 1031e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // Poison if byte in end.offset is unaddressable. 1041e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (end.value > 0 && end.value <= end.offset) { 1051e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany *end.chunk = kAsanUserPoisonedMemoryMagic; 1061e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1071e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany} 1081e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 1099aead37421a6e4bf43265e5195c6ac31fc519982Kostya Serebryanyvoid __asan_unpoison_memory_region(void const volatile *addr, uptr size) { 110cb8c4dce691097718d5af41b36899b72ef4b1d84Alexey Samsonov if (!flags()->allow_user_poisoning || size == 0) return; 1113f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr beg_addr = (uptr)addr; 1123f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany uptr end_addr = beg_addr + size; 113cb8c4dce691097718d5af41b36899b72ef4b1d84Alexey Samsonov if (flags()->verbosity >= 1) { 1145bcca4e33ececdddd8e9e07619c129e870492251Alexey Samsonov Printf("Trying to unpoison memory region [%p, %p)\n", 1155bcca4e33ececdddd8e9e07619c129e870492251Alexey Samsonov (void*)beg_addr, (void*)end_addr); 1161e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1171e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany ShadowSegmentEndpoint beg(beg_addr); 1181e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany ShadowSegmentEndpoint end(end_addr); 1191e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.chunk == end.chunk) { 1201e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(beg.offset < end.offset); 121ee3925515e4c7966f3ef489f687aa7e5692806a9Kostya Serebryany s8 value = beg.value; 1221e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(value == end.value); 1231e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // We unpoison memory bytes up to enbytes up to end.offset if it is not 1241e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany // unpoisoned already. 1251e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (value != 0) { 1262d8b3bdb112ebb8ed3f15ee41d4cebcd683b41b0Kostya Serebryany *beg.chunk = Max(value, end.offset); 1271e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1281e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany return; 1291e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1301e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany CHECK(beg.chunk < end.chunk); 1311e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (beg.offset > 0) { 1321e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany *beg.chunk = 0; 1331e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany beg.chunk++; 1341e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 13509672caefb5694f1981a1712fdefa44840a95e67Alexey Samsonov REAL(memset)(beg.chunk, 0, end.chunk - beg.chunk); 1361e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany if (end.offset > 0 && end.value != 0) { 1372d8b3bdb112ebb8ed3f15ee41d4cebcd683b41b0Kostya Serebryany *end.chunk = Max(end.value, end.offset); 1381e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany } 1391e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany} 1401e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany 1411e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryanybool __asan_address_is_poisoned(void const volatile *addr) { 1423f4c3875c42078e22c7e5356c5746fd18756d958Kostya Serebryany return __asan::AddressIsPoisoned((uptr)addr); 1431e172b4bdec57329bf904f063a29f99cddf2d85fKostya Serebryany} 144d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov 145eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryanyuptr __asan_region_is_poisoned(uptr beg, uptr size) { 146eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany if (!size) return 0; 147eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany uptr end = beg + size; 148eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany if (!AddrIsInMem(beg)) return beg; 149eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany if (!AddrIsInMem(end)) return end; 150eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany uptr aligned_b = RoundUpTo(beg, SHADOW_GRANULARITY); 151eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany uptr aligned_e = RoundDownTo(end, SHADOW_GRANULARITY); 152eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany uptr shadow_beg = MemToShadow(aligned_b); 153eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany uptr shadow_end = MemToShadow(aligned_e); 154eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany // First check the first and the last application bytes, 155eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany // then check the SHADOW_GRANULARITY-aligned region by calling 156eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany // mem_is_zero on the corresponding shadow. 157eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany if (!__asan::AddressIsPoisoned(beg) && 158eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany !__asan::AddressIsPoisoned(end - 1) && 159eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany (shadow_end <= shadow_beg || 160eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany __sanitizer::mem_is_zero((const char *)shadow_beg, 161eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany shadow_end - shadow_beg))) 162eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany return 0; 163eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany // The fast check failed, so we have a poisoned byte somewhere. 164eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany // Find it slowly. 165eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany for (; beg < end; beg++) 166eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany if (__asan::AddressIsPoisoned(beg)) 167eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany return beg; 168eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany UNREACHABLE("mem_is_zero returned false, but poisoned byte was not found"); 169eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany return 0; 170eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany} 171eb2809311c94b73c269ccef8d68ae368642e5754Kostya Serebryany 172dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany#define CHECK_SMALL_REGION(p, size, isWrite) \ 173dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany do { \ 174dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany uptr __p = reinterpret_cast<uptr>(p); \ 175dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany uptr __size = size; \ 176dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany if (UNLIKELY(__asan::AddressIsPoisoned(__p) || \ 177dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany __asan::AddressIsPoisoned(__p + __size - 1))) { \ 178dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany GET_CURRENT_PC_BP_SP; \ 179dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany uptr __bad = __asan_region_is_poisoned(__p, __size); \ 180dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany __asan_report_error(pc, bp, sp, __bad, isWrite, __size);\ 181dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany } \ 182dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany } while (false); \ 183dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 184dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 185dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 1862e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovu16 __sanitizer_unaligned_load16(const uu16 *p) { 187dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), false); 188dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany return *p; 189dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 190dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 191dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 1922e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovu32 __sanitizer_unaligned_load32(const uu32 *p) { 193dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), false); 194dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany return *p; 195dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 196dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 197dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 1982e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovu64 __sanitizer_unaligned_load64(const uu64 *p) { 199dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), false); 200dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany return *p; 201dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 202dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 203dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 2042e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovvoid __sanitizer_unaligned_store16(uu16 *p, u16 x) { 205dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), true); 206dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany *p = x; 207dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 208dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 209dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 2102e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovvoid __sanitizer_unaligned_store32(uu32 *p, u32 x) { 211dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), true); 212dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany *p = x; 213dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 214dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 215dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryanyextern "C" SANITIZER_INTERFACE_ATTRIBUTE 2162e9ffcbc2184f308881fc04ce0799c557b7e5b0fEvgeniy Stepanovvoid __sanitizer_unaligned_store64(uu64 *p, u64 x) { 217dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany CHECK_SMALL_REGION(p, sizeof(*p), true); 218dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany *p = x; 219dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany} 220dc0d17952a060731e47d056f8487d0744037f52eKostya Serebryany 221d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov// This is a simplified version of __asan_(un)poison_memory_region, which 222d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov// assumes that left border of region to be poisoned is properly aligned. 223d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonovstatic void PoisonAlignedStackMemory(uptr addr, uptr size, bool do_poison) { 224d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (size == 0) return; 225d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov uptr aligned_size = size & ~(SHADOW_GRANULARITY - 1); 226d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov PoisonShadow(addr, aligned_size, 227d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov do_poison ? kAsanStackUseAfterScopeMagic : 0); 228d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (size == aligned_size) 229d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov return; 230d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov s8 end_offset = (s8)(size - aligned_size); 231d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov s8* shadow_end = (s8*)MemToShadow(addr + aligned_size); 232d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov s8 end_value = *shadow_end; 233d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (do_poison) { 234d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov // If possible, mark all the bytes mapping to last shadow byte as 235d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov // unaddressable. 236d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (end_value > 0 && end_value <= end_offset) 237bc9940eedb51dd43d844a4c46e17bc89f872781fKostya Serebryany *shadow_end = (s8)kAsanStackUseAfterScopeMagic; 238d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov } else { 239d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov // If necessary, mark few first bytes mapping to last shadow byte 240d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov // as addressable 241d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (end_value != 0) 242d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov *shadow_end = Max(end_value, end_offset); 243d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov } 244d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov} 245d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov 246d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonovvoid __asan_poison_stack_memory(uptr addr, uptr size) { 247d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (flags()->verbosity > 0) 248d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov Report("poisoning: %p %zx\n", (void*)addr, size); 249d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov PoisonAlignedStackMemory(addr, size, true); 250d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov} 251d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov 252d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonovvoid __asan_unpoison_stack_memory(uptr addr, uptr size) { 253d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov if (flags()->verbosity > 0) 254d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov Report("unpoisoning: %p %zx\n", (void*)addr, size); 255d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov PoisonAlignedStackMemory(addr, size, false); 256d4b5db8cb8a7a13bb5cc1d4ce53e8e088303c854Alexey Samsonov} 257