Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754722Ab0KIBQd (ORCPT ); Mon, 8 Nov 2010 20:16:33 -0500 Received: from smtp-out.google.com ([74.125.121.35]:42073 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752458Ab0KIBQc (ORCPT ); Mon, 8 Nov 2010 20:16:32 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer; b=Zkhc5rehqrUer2ET9vh2jb73AZ3y4S0UIugakHTo7fcZa0rhjwA2t4gofYzKkvdMM oxtOyALbV2f2XElz9NKZQ== From: Greg Thelen To: Andrew Morton Cc: Balbir Singh , KAMEZAWA Hiroyuki , Daisuke Nishimura , Johannes Weiner , Wu Fengguang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Greg Thelen Subject: [PATCH] memcg: avoid overflow in memcg_hierarchical_free_pages() Date: Mon, 8 Nov 2010 17:15:20 -0800 Message-Id: <1289265320-7025-1-git-send-email-gthelen@google.com> X-Mailer: git-send-email 1.7.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1251 Lines: 43 Use page counts rather than byte counts to avoid overflowing unsigned long local variables. Signed-off-by: Greg Thelen --- mm/memcontrol.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 6c7115d..b287afd 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1345,17 +1345,17 @@ memcg_hierarchical_free_pages(struct mem_cgroup *mem) { unsigned long free, min_free; - min_free = global_page_state(NR_FREE_PAGES) << PAGE_SHIFT; + min_free = global_page_state(NR_FREE_PAGES); while (mem) { - free = res_counter_read_u64(&mem->res, RES_LIMIT) - - res_counter_read_u64(&mem->res, RES_USAGE); + free = (res_counter_read_u64(&mem->res, RES_LIMIT) - + res_counter_read_u64(&mem->res, RES_USAGE)) >> + PAGE_SHIFT; min_free = min(min_free, free); mem = parent_mem_cgroup(mem); } - /* Translate free memory in pages */ - return min_free >> PAGE_SHIFT; + return min_free; } /* -- 1.7.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/