[PATCH] coverity: idr_get_new_above_int() overrun fix

This patch fixes overrun of array pa:
92   		struct idr_layer *pa[MAX_LEVEL];

in

98   		l = idp->layers;
99   		pa[l--] = NULL;

by passing idp->layers, set in
202  		idp->layers = layers;
to function  sub_alloc in
203  		v = sub_alloc(idp, ptr, &id);
Signed-off-by: NZaur Kambarov <zkambarov@coverity.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

lib/idr.c

@@ -175,7 +175,7 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
 	 * Add a new layer to the top of the tree if the requested
 	 * id is larger than the currently allocated space.
 	 */
-	while ((layers < MAX_LEVEL) && (id >= (1 << (layers*IDR_BITS)))) {
+	while ((layers < (MAX_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) {
 		layers++;
 		if (!p->count)
 			continue;