diff options
| -rw-r--r-- | src/core/alloc_func.hpp | 29 | ||||
| -rw-r--r-- | src/pathfinder/npf/queue.cpp | 2 | ||||
| -rw-r--r-- | src/stdafx.h | 1 |
3 files changed, 28 insertions, 4 deletions
diff --git a/src/core/alloc_func.hpp b/src/core/alloc_func.hpp index 7bd09b004..4ba8c5f53 100644 --- a/src/core/alloc_func.hpp +++ b/src/core/alloc_func.hpp @@ -23,6 +23,29 @@ void NORETURN MallocError(size_t size); void NORETURN ReallocError(size_t size); /** + * Checks whether allocating memory would overflow size_t. + * + * @param element_size Size of the structure to allocate. + * @param num_elements Number of elements to allocate. + */ +static inline void CheckAllocationConstraints(size_t element_size, size_t num_elements) +{ + if (num_elements > SIZE_MAX / element_size) MallocError(SIZE_MAX); +} + +/** + * Checks whether allocating memory would overflow size_t. + * + * @tparam T Structure to allocate. + * @param num_elements Number of elements to allocate. + */ +template <typename T> +static inline void CheckAllocationConstraints(size_t num_elements) +{ + CheckAllocationConstraints(sizeof(T), num_elements); +} + +/** * Simplified allocation function that allocates the specified number of * elements of the given type. It also explicitly casts it to the requested * type. @@ -43,7 +66,7 @@ static FORCEINLINE T *MallocT(size_t num_elements) if (num_elements == 0) return NULL; /* Ensure the size does not overflow. */ - if (num_elements > SIZE_MAX / sizeof(T)) MallocError(SIZE_MAX); + CheckAllocationConstraints<T>(num_elements); T *t_ptr = (T*)malloc(num_elements * sizeof(T)); if (t_ptr == NULL) MallocError(num_elements * sizeof(T)); @@ -100,7 +123,7 @@ static FORCEINLINE T *ReallocT(T *t_ptr, size_t num_elements) } /* Ensure the size does not overflow. */ - if (num_elements > SIZE_MAX / sizeof(T)) MallocError(SIZE_MAX); + CheckAllocationConstraints<T>(num_elements); t_ptr = (T*)realloc(t_ptr, num_elements * sizeof(T)); if (t_ptr == NULL) ReallocError(num_elements * sizeof(T)); @@ -109,7 +132,7 @@ static FORCEINLINE T *ReallocT(T *t_ptr, size_t num_elements) /** alloca() has to be called in the parent function, so define AllocaM() as a macro */ #define AllocaM(T, num_elements) \ - ((num_elements) > SIZE_MAX / sizeof(T) && (MallocError(SIZE_MAX), NULL), \ + (CheckAllocationConstraints<T>(num_elements), \ (T*)alloca((num_elements) * sizeof(T))) #endif /* ALLOC_FUNC_HPP */ diff --git a/src/pathfinder/npf/queue.cpp b/src/pathfinder/npf/queue.cpp index b12c59d6c..f964ece24 100644 --- a/src/pathfinder/npf/queue.cpp +++ b/src/pathfinder/npf/queue.cpp @@ -235,7 +235,7 @@ void Hash::Init(Hash_HashProc *hash, uint num_buckets) uint i; /* Ensure the size won't overflow. */ - assert(num_buckets < SIZE_MAX / (sizeof(*this->buckets) + sizeof(*this->buckets_in_use))); + CheckAllocationConstraints(sizeof(*this->buckets) + sizeof(*this->buckets_in_use), num_buckets); this->hash = hash; this->size = 0; diff --git a/src/stdafx.h b/src/stdafx.h index c50a93eba..bee855169 100644 --- a/src/stdafx.h +++ b/src/stdafx.h @@ -339,6 +339,7 @@ assert_compile(sizeof(uint64) == 8); assert_compile(sizeof(uint32) == 4); assert_compile(sizeof(uint16) == 2); assert_compile(sizeof(uint8) == 1); +assert_compile(SIZE_MAX >= UINT32_MAX); #ifndef M_PI_2 #define M_PI_2 1.57079632679489661923 |