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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8535C282DD for ; Tue, 7 Jan 2020 21:12:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B6662077B for ; Tue, 7 Jan 2020 21:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578431555; bh=RHOGp9HQeQyoK17jjlwbXxaBDWuYVfp1PcCIQL9KW2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=STjJDI0xGCGLQHN81cNHMVywUYVKRKyWM1oOyf+C/N2hai9HL3tt8rQzEvvkmUcna UqYdnsOg1DJJ70TFsJ6Y8kEuwkNO2ckVHDGJbvS+ctoAfiYljqOoX6SA1VHaWpoIA5 5uE3rKW9vcH8UX/ipHUeCf6WeO9BnRcxd8YrlrOQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730085AbgAGVMe (ORCPT ); Tue, 7 Jan 2020 16:12:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:38692 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730056AbgAGVLE (ORCPT ); Tue, 7 Jan 2020 16:11:04 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 846E62080A; Tue, 7 Jan 2020 21:11:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578431464; bh=RHOGp9HQeQyoK17jjlwbXxaBDWuYVfp1PcCIQL9KW2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U3AvVLPs9XxWGE2kdLkKF/LuojzyYN0HjzgeTB56wuCdxbFGBgYHZVtv1LKpR1HvX sJeITLjfNRXouD/94WN2nv12Vg9jBjz8Bo6rb+9RD0TqzrMes4/pA1xoAcPjJLU1P+ d1Exdlsc9di5D9BS1KM7QoMtMR1rsNrTJY7JUwps= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shakeel Butt , Chris Down , Roman Gushchin , Michal Hocko , Johannes Weiner , Andrew Morton , Linus Torvalds Subject: [PATCH 4.14 30/74] memcg: account security cred as well to kmemcg Date: Tue, 7 Jan 2020 21:54:55 +0100 Message-Id: <20200107205200.946162981@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200107205135.369001641@linuxfoundation.org> References: <20200107205135.369001641@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shakeel Butt commit 84029fd04c201a4c7e0b07ba262664900f47c6f5 upstream. The cred_jar kmem_cache is already memcg accounted in the current kernel but cred->security is not. Account cred->security to kmemcg. Recently we saw high root slab usage on our production and on further inspection, we found a buggy application leaking processes. Though that buggy application was contained within its memcg but we observe much more system memory overhead, couple of GiBs, during that period. This overhead can adversely impact the isolation on the system. One source of high overhead we found was cred->security objects, which have a lifetime of at least the life of the process which allocated them. Link: http://lkml.kernel.org/r/20191205223721.40034-1-shakeelb@google.com Signed-off-by: Shakeel Butt Acked-by: Chris Down Reviewed-by: Roman Gushchin Acked-by: Michal Hocko Cc: Johannes Weiner Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- kernel/cred.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/kernel/cred.c +++ b/kernel/cred.c @@ -220,7 +220,7 @@ struct cred *cred_alloc_blank(void) new->magic = CRED_MAGIC; #endif - if (security_cred_alloc_blank(new, GFP_KERNEL) < 0) + if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0) goto error; return new; @@ -279,7 +279,7 @@ struct cred *prepare_creds(void) new->security = NULL; #endif - if (security_prepare_creds(new, old, GFP_KERNEL) < 0) + if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0) goto error; validate_creds(new); return new; @@ -654,7 +654,7 @@ struct cred *prepare_kernel_cred(struct #ifdef CONFIG_SECURITY new->security = NULL; #endif - if (security_prepare_creds(new, old, GFP_KERNEL) < 0) + if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0) goto error; put_cred(old);