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Difference between revisions of "Race condition within a thread"

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{{template:CandidateForDeletion}}
  
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#REDIRECT [[Race Conditions]]
  
{{Template:SecureSoftware}}
 
  
==Overview==
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Last revision (mm/dd/yy): '''{{REVISIONMONTH}}/{{REVISIONDAY}}/{{REVISIONYEAR}}'''
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==Description==
  
 
If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.  
 
If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.  
  
==Consequences ==
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'''Consequences'''
  
* Integrity: The main problem is that - if a lock is overcome - data could be altered in a bad state.
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* Integrity: The main problem is that - if a lock is overcome - data could be altered in a bad state.
  
==Exposure period ==
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'''Exposure period'''
  
* Design: Use a language which provides facilities to easily use threads safely.  
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* Design: Use a language which provides facilities to easily use threads safely.  
  
==Platform ==
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'''Platform'''
  
* Languages: Any language with threads
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* Languages: Any language with threads
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* Operating platforms: All
  
* Operating platforms: All
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'''Required resources'''
 
 
==Required resources ==
 
  
 
Any
 
Any
  
==Severity ==
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'''Severity'''
  
 
High
 
High
  
==Likelihood   of exploit ==
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'''Likelihood of exploit'''
  
 
Medium
 
Medium
  
==Avoidance and mitigation ==
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* Design: Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multi-threaded environment.
  
==Discussion ==
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* Design: Create resource-locking sanity checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.
  
* Design: Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multi-threaded environment.
 
  
* Design: Create resource-locking sanity checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.
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==Risk Factors==
  
==Examples ==
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TBD
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==Examples==
  
 
In C/C++:
 
In C/C++:
  
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<pre>
 
int foo = 0;
 
int foo = 0;
 
     int storenum(int num)
 
     int storenum(int num)
Line 54: Line 61:
 
             return foo;   
 
             return foo;   
 
     }
 
     }
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</pre>
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In Java:
 
In Java:
  
public classRace {
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<pre>public classRace {
 
   static int foo = 0;
 
   static int foo = 0;
  
Line 70: Line 79:
 
   }
 
   }
 
}
 
}
==Related problems ==
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</pre>
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==Related [[Attacks]]==
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* [[Attack 1]]
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* [[Attack 2]]
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==Related [[Vulnerabilities]]==
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* [[Vulnerability 1]]
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* [[Vulnerabiltiy 2]]
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==Related [[Controls]]==
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* [[Control 1]]
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* [[Control 2]]
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==Related [[Technical Impacts]]==
  
Not available.
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* [[Technical Impact 1]]
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* [[Technical Impact 2]]
  
==Categories ==
 
  
[[Category:Vulnerability]]
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==References==
  
[[Category:Synchronization and Timing Errror]]
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TBD

Latest revision as of 12:26, 7 April 2009

Template:CandidateForDeletion

#REDIRECT Race Conditions


Last revision (mm/dd/yy): 04/7/2009


Description

If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.

Consequences

  • Integrity: The main problem is that - if a lock is overcome - data could be altered in a bad state.

Exposure period

  • Design: Use a language which provides facilities to easily use threads safely.

Platform

  • Languages: Any language with threads
  • Operating platforms: All

Required resources

Any

Severity

High

Likelihood of exploit

Medium

  • Design: Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multi-threaded environment.
  • Design: Create resource-locking sanity checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.


Risk Factors

TBD


Examples

In C/C++:

int foo = 0;
    int storenum(int num)
    {
        static int counter = 0;
        counter++;
        if (num > foo) 
            foo = num;
            return foo;   
    }

In Java:

public classRace {
  static int foo = 0;

  public static void main() {
    new Threader().start();
    foo = 1;
  }

  public static class Threader extends Thread {
    public void run() { 
      System.out.println(foo);
    }
  }
}


Related Attacks


Related Vulnerabilities

Related Controls


Related Technical Impacts


References

TBD