From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id DFAB56B00C5 for ; Mon, 8 Nov 2010 22:33:47 -0500 (EST) From: 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> Sender: owner-linux-mm@kvack.org 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 List-ID: 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org