From patchwork Tue Jul 18 01:08:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haitao Huang X-Patchwork-Id: 13316658 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8615BEB64DC for ; Tue, 18 Jul 2023 01:09:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229670AbjGRBJF (ORCPT ); Mon, 17 Jul 2023 21:09:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230133AbjGRBJF (ORCPT ); Mon, 17 Jul 2023 21:09:05 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9146D8; Mon, 17 Jul 2023 18:09:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1689642544; x=1721178544; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U+HYDr0YJ1RDyX2/gcHKL0bAVncJHhQaWyxrxc5y+kQ=; b=IXuhTp7EdtszAEwpGuUiCPemVyaHHaYhKMbYGxKCQwae1bt0LJC/lD17 QCYK9G0NWK+WUH4P81S9t/isYrrdfTUnmzg8nq1dqA0xMX5eOrthZvkyU 07fUdaKA1sshaZZ7BCsi7b9ygELqW4kBwOtE5h625R1LQZb+VUp7K4XdL VxFUJop3SJIRbfCS+PcQE9Nm0IlOh8cAzUQOJkwbckB4JzrwPGCzqQsVZ sG2J2GWhynYsRcoS9tBwUR1BEaE4aoswZX6qykMi2CAteKRSifESlT6v2 YZ/pcm8mLv9eJgCmEpQBQ06TCLjqsvR5FOX5lXSDWLJ9lCazmEBrErFR3 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10774"; a="432255248" X-IronPort-AV: E=Sophos;i="6.01,211,1684825200"; d="scan'208";a="432255248" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jul 2023 18:08:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10774"; a="793437554" X-IronPort-AV: E=Sophos;i="6.01,211,1684825200"; d="scan'208";a="793437554" Received: from b4969161e530.jf.intel.com ([10.165.56.46]) by fmsmga004.fm.intel.com with ESMTP; 17 Jul 2023 18:08:46 -0700 From: Haitao Huang To: tj@kernel.org, jarkko@kernel.org, dave.hansen@linux.intel.com, linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org, cgroups@vger.kernel.org, Zefan Li , Johannes Weiner Cc: vipinsh@google.com, kai.huang@intel.com, reinette.chatre@intel.com, zhiquan1.li@intel.com, kristen@linux.intel.com Subject: [PATCH 1/2] cgroup/misc: Fix an overflow Date: Mon, 17 Jul 2023 18:08:44 -0700 Message-Id: <20230718010845.35197-1-haitao.huang@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org The variable 'new_usage' in misc_cg_try_charge() may overflow if it becomes above INT_MAX. This was observed when I implement the new SGX EPC cgroup[1] as a misc cgroup and test on a platform with large SGX EPC sizes. Change type of new_usage to long from int and check overflow. Fixes: a72232eabdfc ("cgroup: Add misc cgroup controller") Signed-off-by: Haitao Huang [1] https://lore.kernel.org/linux-sgx/20230712230202.47929-1-haitao.huang@linux.intel.com/ --- kernel/cgroup/misc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/cgroup/misc.c b/kernel/cgroup/misc.c index fe3e8a0eb7ed..b127607837c6 100644 --- a/kernel/cgroup/misc.c +++ b/kernel/cgroup/misc.c @@ -143,7 +143,7 @@ int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, struct misc_cg *i, *j; int ret; struct misc_res *res; - int new_usage; + long new_usage; if (!(valid_type(type) && cg && READ_ONCE(misc_res_capacity[type]))) return -EINVAL; @@ -156,7 +156,8 @@ int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, new_usage = atomic_long_add_return(amount, &res->usage); if (new_usage > READ_ONCE(res->max) || - new_usage > READ_ONCE(misc_res_capacity[type])) { + new_usage > READ_ONCE(misc_res_capacity[type]) || + new_usage < 0) { ret = -EBUSY; goto err_charge; }