[PATCH] drivers/scsi/dpt_i2o.c: fix a NULL pointer dereference

The Coverity checker spotted this obvious NULL pointer dereference.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Mark Salyzyn <mark_salyzyn@adaptec.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/scsi/dpt_i2o.c

@@ -816,7 +816,7 @@ static int adpt_hba_reset(adpt_hba* pHba)
 static void adpt_i2o_sys_shutdown(void)
 {
 	adpt_hba *pHba, *pNext;
-	struct adpt_i2o_post_wait_data *p1, *p2;
+	struct adpt_i2o_post_wait_data *p1, *old;
 
 	 printk(KERN_INFO"Shutting down Adaptec I2O controllers.\n");
 	 printk(KERN_INFO"   This could take a few minutes if there are many devices attached\n");
@@ -830,13 +830,14 @@ static void adpt_i2o_sys_shutdown(void)
 	}
 
 	/* Remove any timedout entries from the wait queue.  */
-	p2 = NULL;
 //	spin_lock_irqsave(&adpt_post_wait_lock, flags);
 	/* Nothing should be outstanding at this point so just
 	 * free them 
 	 */
-	for(p1 = adpt_post_wait_queue; p1; p2 = p1, p1 = p2->next) {
-		kfree(p1);
+	for(p1 = adpt_post_wait_queue; p1;) {
+		old = p1;
+		p1 = p1->next;
+		kfree(old);
 	}
 //	spin_unlock_irqrestore(&adpt_post_wait_lock, flags);
 	adpt_post_wait_queue = NULL;