Bug in semop() in multiprocess environment?

Ivan Shcheklein shcheklein at gmail.com
Sun Nov 18 09:23:53 PST 2007

Hi All,

It seems to me that there is a bug in the semop() code:

After wakeup we see the following:

         * The semaphore is still alive.  Readjust the count of
         * waiting processes.
        if (sopptr->sem_op == 0)

It seems to me that "semptr" can be invalid after wakeup. For example,
semaphore's base can be changed after remove called on another previously
created semaphore.

I think semptr must be renewed after wakeup.

Ivan Shcheklein

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