1. Race in mempool_resize: memcpy can copy at the end of the kmalloced 
elements.
 2. when new_min_nr is same as min_nr, instead of reallocate and copy, just 
return,
    changed '<' to '<='.
 3. Changed while condition to the same sense of if condition from '>' to '<'; 
it is
    easy to think with only one of the left and right brains at a time.
  
Signed-off-by: Prasanna Meda <[EMAIL PROTECTED]>


--- Linux/mm/mempool.c  Mon Feb 14 23:03:00 2005
+++ linux/mm/mempool.c  Mon Feb 14 23:03:04 2005
@@ -114,8 +114,8 @@
        BUG_ON(new_min_nr <= 0);
 
        spin_lock_irqsave(&pool->lock, flags);
-       if (new_min_nr < pool->min_nr) {
-               while (pool->curr_nr > new_min_nr) {
+       if (new_min_nr <= pool->min_nr) {
+               while (new_min_nr < pool->curr_nr) {
                        element = remove_element(pool);
                        spin_unlock_irqrestore(&pool->lock, flags);
                        pool->free(element, pool->pool_data);
@@ -132,6 +132,12 @@
                return -ENOMEM;
 
        spin_lock_irqsave(&pool->lock, flags);
+       if (unlikely(new_min_nr <= pool->min_nr)) {
+               /* Raced, other resize will do our work */
+               spin_unlock_irqrestore(&pool->lock, flags);
+               kfree(new_elements);
+               goto out;
+       }
        memcpy(new_elements, pool->elements,
                        pool->curr_nr * sizeof(*new_elements));
        kfree(pool->elements);
@@ -149,7 +155,7 @@
                } else {
                        spin_unlock_irqrestore(&pool->lock, flags);
                        pool->free(element, pool->pool_data);   /* Raced */
-                       spin_lock_irqsave(&pool->lock, flags);
+                       goto out;
                }
        }
 out_unlock:
-
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