IO.NEGFD : 負のファイルディスクリプタ

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CodeSonar^® 9.2p0

CONFIDENTIAL

CodeSecure Inc

IO.NEGFD : 負のファイルディスクリプタ

要旨

ファイルディスクリプタに負の数値を使用しようとしています。

プロパティ

MisraC2025

MisraC2025:D.4.1

Run-time failures shall be minimized

MisraC2023

MisraC2023:D.4.1

Run-time failures shall be minimized

Misra2012

Misra2012:D.4.1

Run-time failures shall be minimized

MisraC++2023

MisraC++2023:0.3.2

A function call shall not violate the function's preconditions

CWE

CWE:687

Function Call With Incorrectly Specified Argument Value

Insecure design

Insecure Design

CWE:252	Unchecked Return Value

例

#include <fcntl.h>
#include <unistd.h>

int negfd_nocheck(void){
  return close(open("myfile.txt",O_RDONLY)); /* 'Negative file descriptor' warning issued here
                                              *  - open() returns -1 on error
                                              */
}

int negfd_check(void){
  int rv;
  rv = open("myfile.txt",O_RDONLY);
  if (rv < 0){
    return -1;
  }
  return close(rv);
}

ワーニングを引き起こす関数

CodeSonar ships with library models that allow it to a large number of functions that take a file descriptor or socket descriptor argument. If one of these functions is called with a negative value in the file/socket descriptor parameter position, a warning will be issued.

If you have created a custom library model for some function f() in terms of one of these existing models, calls to f() will also be capable of triggering Negative file descriptor warnings.

	Functions that can trigger warnings include...
libc	dup(), fdopen(), sendmsg(),
Win32	_dup(), _fstat64(), _write()

Functions that can trigger warnings include...

libc

dup(), fdopen(), sendmsg(),

Win32

_dup(), _fstat64(), _write()

関連のある設定ファイルパラメータ

設定ファイルの以下のパラメータがこのワーニングクラスのチェックに影響します。