libsanitizer/sanitizer_common/sanitizer_allocator_checks.h

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