CWE-467: Use of sizeof() on a Pointer Type
CWE版本: 4.18
更新日期: 2025-09-09
弱点描述
The code calls sizeof() on a pointer type, which can be an incorrect calculation if the programmer intended to determine the size of the data that is being pointed to.
扩展描述
The use of sizeof() on a pointer can sometimes generate useful information. An obvious case is to find out the wordsize on a platform. More often than not, the appearance of sizeof(pointer) indicates a bug.
常见后果
影响范围: Integrity Confidentiality
技术影响: Modify Memory Read Memory
说明: This error can often cause one to allocate a buffer that is much smaller than what is needed, leading to resultant weaknesses such as buffer overflows.
潜在缓解措施
阶段: Implementation
描述: Use expressions such as "sizeof(*pointer)" instead of "sizeof(pointer)", unless you intend to run sizeof() on a pointer type to gain some platform independence or if you are allocating a variable on the stack.
检测方法
方法: Automated Static Analysis
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
有效性: High
引入模式
| 阶段 | 说明 |
|---|---|
| Implementation | - |
适用平台
编程语言
分类映射
| 分类名称 | 条目ID | 条目名称 | 映射适配度 |
|---|---|---|---|
| CLASP | - | Use of sizeof() on a pointer type | - |
| CERT C Secure Coding | ARR01-C | Do not apply the sizeof operator to a pointer when taking the size of an array | - |
| CERT C Secure Coding | MEM35-C | Allocate sufficient memory for an object | CWE More Abstract |
| Software Fault Patterns | SFP10 | Incorrect Buffer Length Computation | - |