a exit() bug in multithreaded program

[SHEN Feng]

Hi,

 

In the function exit(), the global variable __exit_funcs isn't protected for multithreaded program. But __exit_funcs at __new_exit_fn() in cxa_atexit.c is protected by a lock. The function __new_exit_fn() is called by atexit() and on_exit(). So __exit_funcs at exit() should also be protected by the lock. It’s a bug.

 

I have had a test on this function. The test function exit_test.c and the result file exit_test_result_redhat.log are attached. From them we can concluded that the exit() may be unsafe in multithreaded program.

 

B.R.
                  SHEN Feng

exit_test_result_redhat.log
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exit_test.c
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