From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2117C433F5 for ; Fri, 14 Jan 2022 22:05:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4E74C6B00E9; Fri, 14 Jan 2022 17:05:45 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 495EC6B00EB; Fri, 14 Jan 2022 17:05:45 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 360B16B00EC; Fri, 14 Jan 2022 17:05:45 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0179.hostedemail.com [216.40.44.179]) by kanga.kvack.org (Postfix) with ESMTP id 231DA6B00E9 for ; Fri, 14 Jan 2022 17:05:45 -0500 (EST) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id D9EAD998B4 for ; Fri, 14 Jan 2022 22:05:44 +0000 (UTC) X-FDA: 79030275408.20.DA77EB6 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf27.hostedemail.com (Postfix) with ESMTP id 62A8840002 for ; Fri, 14 Jan 2022 22:05:44 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B52996200C; Fri, 14 Jan 2022 22:05:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2ED4C36AE9; Fri, 14 Jan 2022 22:05:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1642197943; bh=JexHpmoYiIAWantUDQDX6rbtfMsRQ+uyVXiLRCHcRLg=; h=Date:From:To:Subject:In-Reply-To:From; b=PE5EYzOe0G1G5WjElw6bvndsE/3W2jz6AAxalB/p/zNHtS0y1A7vtn0TRfPsDRxLt 0FFkgAKaZ0xwW4fRK31ryrcPnMbD+/72pyf+fzK4gyFOt9xIivF5t10t0zVasWdKju V3RgsxWqQzf2c2RtE+ab5wNoO9yrZNnpH2pnchXA= Date: Fri, 14 Jan 2022 14:05:42 -0800 From: Andrew Morton To: akpm@linux-foundation.org, hannes@cmpxchg.org, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, songmuchun@bytedance.com, torvalds@linux-foundation.org, vdavydov.dev@gmail.com, wangweiyang2@huawei.com Subject: [patch 052/146] mm/memcg: use struct_size() helper in kzalloc() Message-ID: <20220114220542.X_Xm3i4Ga%akpm@linux-foundation.org> In-Reply-To: <20220114140222.6b14f0061194d3200000c52d@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 62A8840002 X-Stat-Signature: q8dex4t4fgmwsrcdnafpnfdhu9jsypri Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=PE5EYzOe; dmarc=none; spf=pass (imf27.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam03 X-HE-Tag: 1642197944-856119 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Wang Weiyang Subject: mm/memcg: use struct_size() helper in kzalloc() Make use of the struct_size() helper instead of an open-coded version, in order to avoid any potential type mistakes or integer overflows that, in the worst scenario, could lead to heap overflows. Link: https://github.com/KSPP/linux/issues/160 Link: https://lkml.kernel.org/r/20211216022024.127375-1-wangweiyang2@huawei.com Signed-off-by: Wang Weiyang Reviewed-by: Muchun Song Acked-by: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Signed-off-by: Andrew Morton --- mm/memcontrol.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) --- a/mm/memcontrol.c~mm-memcg-use-struct_size-helper-in-kzalloc +++ a/mm/memcontrol.c @@ -5122,15 +5122,11 @@ static void mem_cgroup_free(struct mem_c static struct mem_cgroup *mem_cgroup_alloc(void) { struct mem_cgroup *memcg; - unsigned int size; int node; int __maybe_unused i; long error = -ENOMEM; - size = sizeof(struct mem_cgroup); - size += nr_node_ids * sizeof(struct mem_cgroup_per_node *); - - memcg = kzalloc(size, GFP_KERNEL); + memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); if (!memcg) return ERR_PTR(error); _