DeleteMidQEntry(struct mid_q_entry *midEntry)
{
#ifdef CONFIG_CIFS_STATS2
	__le16 command = midEntry->server->vals->lock_cmd;
	unsigned long now;
#endif
	midEntry->mid_state = MID_FREE;
	atomic_dec(&midCount);
	if (midEntry->large_buf)
		cifs_buf_release(midEntry->resp_buf);
	else
		cifs_small_buf_release(midEntry->resp_buf);
#ifdef CONFIG_CIFS_STATS2
	now = jiffies;
	/* commands taking longer than one second are indications that
	   something is wrong, unless it is quite a slow link or server */
	if ((now - midEntry->when_alloc) > HZ) {
		if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) {
			printk(KERN_DEBUG " CIFS slow rsp: cmd %d mid %llu",
			       midEntry->command, midEntry->mid);
			printk(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
			       now - midEntry->when_alloc,
			       now - midEntry->when_sent,
			       now - midEntry->when_received);
		}
	}
#endif
	mempool_free(midEntry, cifs_mid_poolp);
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.