ABSTRACT

If a parent process finishes execution normally before the threads it has spawned, the threads can be terminated prematurely.

EXPLANATION

Threads spawned by calling pthread_create() from the main() function of the parent process will be terminated prematurely if the parent process finishes execution before any the threads it has spawned without calling pthread_exit(). Calling pthread_exit() guarantees that the parent process will be kept alive until all of its threads have finished execution. Alternatively, the parent process can call pthread_join on all of the child threads and ensure they will complete before the process concludes.

Example 1: The following code uses pthread_create() to create a thread and then exits normally. If the child thread has not completed its execution by the time the main() function returns, then it will be terminated prematurely.


void *Simple(void *threadid)
{
...
pthread_exit(NULL);
}

int main(int argc, char *argv[]) {
int rc;
pthread_t pt;
rc = pthread_create(&pt, NULL, Simple, (void *)t);
if (rc){
exit(-1);
}
}

REFERENCES

[1] Standards Mapping - OWASP Top 10 2004 - (OWASP 2004) A9 Application Denial of Service

[2] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP6080 CAT II

[3] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 730

[4] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 6.5.9