1//===-- sanitizer_allocator_checks.h ----------------------------*- C++ -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// Various checks shared between ThreadSanitizer, MemorySanitizer, etc. memory 10// allocators. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef SANITIZER_ALLOCATOR_CHECKS_H 15#define SANITIZER_ALLOCATOR_CHECKS_H 16 17#include "sanitizer_internal_defs.h" 18#include "sanitizer_common.h" 19#include "sanitizer_platform.h" 20 21namespace __sanitizer { 22 23// The following is defined in a separate compilation unit to avoid pulling in 24// sanitizer_errno.h in this header, which leads to conflicts when other system 25// headers include errno.h. This is usually the result of an unlikely event, 26// and as such we do not care as much about having it inlined. 27void SetErrnoToENOMEM(); 28 29// A common errno setting logic shared by almost all sanitizer allocator APIs. 30inline void *SetErrnoOnNull(void *ptr) { 31 if (UNLIKELY(!ptr)) 32 SetErrnoToENOMEM(); 33 return ptr; 34} 35 36// In case of the check failure, the caller of the following Check... functions 37// should "return POLICY::OnBadRequest();" where POLICY is the current allocator 38// failure handling policy. 39 40// Checks aligned_alloc() parameters, verifies that the alignment is a power of 41// two and that the size is a multiple of alignment for POSIX implementation, 42// and a bit relaxed requirement for non-POSIX ones, that the size is a multiple 43// of alignment. 44inline bool CheckAlignedAllocAlignmentAndSize(uptr alignment, uptr size) { 45#if SANITIZER_POSIX 46 return alignment != 0 && IsPowerOfTwo(alignment) && 47 (size & (alignment - 1)) == 0; 48#else 49 return alignment != 0 && size % alignment == 0; 50#endif 51} 52 53// Checks posix_memalign() parameters, verifies that alignment is a power of two 54// and a multiple of sizeof(void *). 55inline bool CheckPosixMemalignAlignment(uptr alignment) { 56 return alignment != 0 && IsPowerOfTwo(alignment) && 57 (alignment % sizeof(void *)) == 0; 58} 59 60// Returns true if calloc(size, n) call overflows on size*n calculation. 61inline bool CheckForCallocOverflow(uptr size, uptr n) { 62 if (!size) 63 return false; 64 uptr max = (uptr)-1L; 65 return (max / size) < n; 66} 67 68// Returns true if the size passed to pvalloc overflows when rounded to the next 69// multiple of page_size. 70inline bool CheckForPvallocOverflow(uptr size, uptr page_size) { 71 return RoundUpTo(size, page_size) < size; 72} 73 74} // namespace __sanitizer 75 76#endif // SANITIZER_ALLOCATOR_CHECKS_H 77