To get a trial key
fill out the form below
Team license
Enterprise license
** By clicking this button you agree to our Privacy Policy statement

Request our prices
New License
License Renewal
--Select currency--
USD
EUR
RUB
* By clicking this button you agree to our Privacy Policy statement

Free PVS-Studio license for Microsoft MVP specialists
** By clicking this button you agree to our Privacy Policy statement

To get the licence for your open-source project, please fill out this form
** By clicking this button you agree to our Privacy Policy statement

I am interested to try it on the platforms:
** By clicking this button you agree to our Privacy Policy statement

Message submitted.

Your message has been sent. We will email you at


If you haven't received our response, please do the following:
check your Spam/Junk folder and click the "Not Spam" button for our message.
This way, you won't miss messages from our team in the future.

>
>
>
V3057. Function receives an odd argumen…
Analyzer diagnostics
General Analysis (C++)
General Analysis (C#)
General Analysis (Java)
Diagnosis of micro-optimizations (C++)
Diagnosis of 64-bit errors (Viva64, C++)
Customer specific requests (C++)
MISRA errors
AUTOSAR errors
OWASP errors (C#)
Problems related to code analyzer
Additional information
Contents

V3057. Function receives an odd argument.

Feb 20 2016

The analyzer detected a possible error that has to do with passing a suspicious value as an argument to a function.

Consider the following examples:

Invalid characters in a path

string GetLogPath(string root)
{
  return System.IO.Path.Combine(root, @"\my|folder\log.txt");
}

A path containing invalid character '|' is passed to function 'Combine()'. It will result in an 'ArgumentException'.

The fixed version:

string GetLogPath(string root)
{
  return System.IO.Path.Combine(root, @"\my\folder\log.txt"); 
}

Suspicious argument to format function

string.Format(mask, 1, 2, mask);

The 'string.Format()' function replaces one or more format items in a specified string. An attempt to write the same string into the format string is treated as suspicious by the analyzer.

Invalid index

var pos = mask.IndexOf('\0');
if (pos != 0)
    asciiname = mask.Substring(0, pos);

'IndexOf()' returns the position of a specified argument. If the argument is not found, the function returns the value '-1'. And passing a negative index to function 'Substring()' results in an 'ArgumentOutOfRangeException'.

The fixed version:

var pos = mask.IndexOf('\0');
if (pos > 0)
    asciiname = mask.Substring(0, pos);

Note that the analyzer may also issue a warning when a correct argument is passed to the method, but the corresponding parameter inside the method may take an invalid value.

static void Bar(string[] data, int index, int length)
{
  if (index < 0)
    throw new Exception(....);

  if (data.Length < index + length)
    length = data.Length - index;             // <=

  ....
  Array.Copy(data, index, result, 0, length); // <=
}

static void Foo(string[] args)
{
  Bar(args, 4, 2);                            // <=
  ....
}

In this case, the analyzer will issue a warning that the 'length' parameter used in the 'Array.Copy' method call may take a negative value. This parameter corresponds to the '2' argument passed in the 'Bar' call. This will result in 'ArgumentOutOfRangeException'.

Indeed, if the size of the 'args' array ('data' inside the 'Bar' method) is less than 4, a negative value will be written to 'length' inside 'Bar', despite the fact that a positive value (2) is passed to the method. As a result, an exception will be thrown when calling 'Array.Copy'.

In the 'Bar' method, you should add a check for the new 'length' value and the necessary processing of negative values:

if (data.Length < index + length)
  length = data.Length - index;
             
if (length < 0)
  .... // Error handling

This diagnostic is classified as:

You can look at examples of errors detected by the V3057 diagnostic.

Unicorn with delicious cookie
Our website uses cookies to enhance your browsing experience.
Accept