| //===-- asan_interceptors_memintrinsics.h -----------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===---------------------------------------------------------------------===// |
| // |
| // This file is a part of AddressSanitizer, an address sanity checker. |
| // |
| // ASan-private header for asan_memintrin.cc |
| //===---------------------------------------------------------------------===// |
| #ifndef ASAN_MEMINTRIN_H |
| #define ASAN_MEMINTRIN_H |
| |
| #include "asan_interface_internal.h" |
| #include "asan_internal.h" |
| #include "asan_mapping.h" |
| #include "interception/interception.h" |
| |
| DECLARE_REAL(void*, memcpy, void *to, const void *from, uptr size) |
| DECLARE_REAL(void*, memset, void *block, int c, uptr size) |
| |
| namespace __asan { |
| |
| // Return true if we can quickly decide that the region is unpoisoned. |
| // We assume that a redzone is at least 16 bytes. |
| static inline bool QuickCheckForUnpoisonedRegion(uptr beg, uptr size) { |
| if (size == 0) return true; |
| if (size <= 32) |
| return !AddressIsPoisoned(beg) && |
| !AddressIsPoisoned(beg + size - 1) && |
| !AddressIsPoisoned(beg + size / 2); |
| if (size <= 64) |
| return !AddressIsPoisoned(beg) && |
| !AddressIsPoisoned(beg + size / 4) && |
| !AddressIsPoisoned(beg + size - 1) && |
| !AddressIsPoisoned(beg + 3 * size / 4) && |
| !AddressIsPoisoned(beg + size / 2); |
| return false; |
| } |
| |
| struct AsanInterceptorContext { |
| const char *interceptor_name; |
| }; |
| |
| // We implement ACCESS_MEMORY_RANGE, ASAN_READ_RANGE, |
| // and ASAN_WRITE_RANGE as macro instead of function so |
| // that no extra frames are created, and stack trace contains |
| // relevant information only. |
| // We check all shadow bytes. |
| #define ACCESS_MEMORY_RANGE(ctx, offset, size, isWrite) do { \ |
| uptr __offset = (uptr)(offset); \ |
| uptr __size = (uptr)(size); \ |
| uptr __bad = 0; \ |
| if (__offset > __offset + __size) { \ |
| GET_STACK_TRACE_FATAL_HERE; \ |
| ReportStringFunctionSizeOverflow(__offset, __size, &stack); \ |
| } \ |
| if (!QuickCheckForUnpoisonedRegion(__offset, __size) && \ |
| (__bad = __asan_region_is_poisoned(__offset, __size))) { \ |
| AsanInterceptorContext *_ctx = (AsanInterceptorContext *)ctx; \ |
| bool suppressed = false; \ |
| if (_ctx) { \ |
| suppressed = IsInterceptorSuppressed(_ctx->interceptor_name); \ |
| if (!suppressed && HaveStackTraceBasedSuppressions()) { \ |
| GET_STACK_TRACE_FATAL_HERE; \ |
| suppressed = IsStackTraceSuppressed(&stack); \ |
| } \ |
| } \ |
| if (!suppressed) { \ |
| GET_CURRENT_PC_BP_SP; \ |
| ReportGenericError(pc, bp, sp, __bad, isWrite, __size, 0, false);\ |
| } \ |
| } \ |
| } while (0) |
| |
| // memcpy is called during __asan_init() from the internals of printf(...). |
| // We do not treat memcpy with to==from as a bug. |
| // See http://llvm.org/bugs/show_bug.cgi?id=11763. |
| #define ASAN_MEMCPY_IMPL(ctx, to, from, size) \ |
| do { \ |
| if (UNLIKELY(!asan_inited)) return internal_memcpy(to, from, size); \ |
| if (asan_init_is_running) { \ |
| return REAL(memcpy)(to, from, size); \ |
| } \ |
| ENSURE_ASAN_INITED(); \ |
| if (flags()->replace_intrin) { \ |
| if (to != from) { \ |
| CHECK_RANGES_OVERLAP("memcpy", to, size, from, size); \ |
| } \ |
| ASAN_READ_RANGE(ctx, from, size); \ |
| ASAN_WRITE_RANGE(ctx, to, size); \ |
| } \ |
| return REAL(memcpy)(to, from, size); \ |
| } while (0) |
| |
| // memset is called inside Printf. |
| #define ASAN_MEMSET_IMPL(ctx, block, c, size) \ |
| do { \ |
| if (UNLIKELY(!asan_inited)) return internal_memset(block, c, size); \ |
| if (asan_init_is_running) { \ |
| return REAL(memset)(block, c, size); \ |
| } \ |
| ENSURE_ASAN_INITED(); \ |
| if (flags()->replace_intrin) { \ |
| ASAN_WRITE_RANGE(ctx, block, size); \ |
| } \ |
| return REAL(memset)(block, c, size); \ |
| } while (0) |
| |
| #define ASAN_MEMMOVE_IMPL(ctx, to, from, size) \ |
| do { \ |
| if (UNLIKELY(!asan_inited)) return internal_memmove(to, from, size); \ |
| ENSURE_ASAN_INITED(); \ |
| if (flags()->replace_intrin) { \ |
| ASAN_READ_RANGE(ctx, from, size); \ |
| ASAN_WRITE_RANGE(ctx, to, size); \ |
| } \ |
| return internal_memmove(to, from, size); \ |
| } while (0) |
| |
| #define ASAN_READ_RANGE(ctx, offset, size) \ |
| ACCESS_MEMORY_RANGE(ctx, offset, size, false) |
| #define ASAN_WRITE_RANGE(ctx, offset, size) \ |
| ACCESS_MEMORY_RANGE(ctx, offset, size, true) |
| |
| // Behavior of functions like "memcpy" or "strcpy" is undefined |
| // if memory intervals overlap. We report error in this case. |
| // Macro is used to avoid creation of new frames. |
| static inline bool RangesOverlap(const char *offset1, uptr length1, |
| const char *offset2, uptr length2) { |
| return !((offset1 + length1 <= offset2) || (offset2 + length2 <= offset1)); |
| } |
| #define CHECK_RANGES_OVERLAP(name, _offset1, length1, _offset2, length2) \ |
| do { \ |
| const char *offset1 = (const char *)_offset1; \ |
| const char *offset2 = (const char *)_offset2; \ |
| if (RangesOverlap(offset1, length1, offset2, length2)) { \ |
| GET_STACK_TRACE_FATAL_HERE; \ |
| bool suppressed = IsInterceptorSuppressed(name); \ |
| if (!suppressed && HaveStackTraceBasedSuppressions()) { \ |
| suppressed = IsStackTraceSuppressed(&stack); \ |
| } \ |
| if (!suppressed) { \ |
| ReportStringFunctionMemoryRangesOverlap(name, offset1, length1, \ |
| offset2, length2, &stack); \ |
| } \ |
| } \ |
| } while (0) |
| |
| } // namespace __asan |
| |
| #endif // ASAN_MEMINTRIN_H |