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 087AAC282DD for ; Tue, 7 Jan 2020 21:05:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D26E32187F for ; Tue, 7 Jan 2020 21:05:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578431148; bh=RHOGp9HQeQyoK17jjlwbXxaBDWuYVfp1PcCIQL9KW2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Vy9P3VnUPN6l4UgNIGUlmsfTA5OsW+e35a+ZG/m8fegXdmjdBOi697/oXznsghDwp hV4WClvvy+PJMYSnHA0fmLVN6KKDQHPlFPXkDVjywXF9AtmTR2iNk67TY1kYY2Z++a HxhdsbqyR2ZTIWvkLvmqaGSZIU3CDg33wWIHdaEQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729057AbgAGVFr (ORCPT ); Tue, 7 Jan 2020 16:05:47 -0500 Received: from mail.kernel.org ([198.145.29.99]:53050 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728478AbgAGVFq (ORCPT ); Tue, 7 Jan 2020 16:05:46 -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 6F339208C4; Tue, 7 Jan 2020 21:05:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578431145; bh=RHOGp9HQeQyoK17jjlwbXxaBDWuYVfp1PcCIQL9KW2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0vCI+9ISt0OkFf4fKU8yR4sT7yolPDtsdA6SJCdRhIJ6v4wh4/X/vrX3dazS5iOG2 hDC1H1vBJJK2DzSavy3U6pvBB0YNXzsocgmHqzTcNDhongjtl1jE57KuedrL9wQIXr IqQ66eEqFKWIVxhNHdm8YYJAuuNc8N/KKDLgSojg= 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 4.19 053/115] memcg: account security cred as well to kmemcg Date: Tue, 7 Jan 2020 21:54:23 +0100 Message-Id: <20200107205302.692285245@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200107205240.283674026@linuxfoundation.org> References: <20200107205240.283674026@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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);