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 75E81C433EF for ; Mon, 23 May 2022 20:39:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E0FDA6B0072; Mon, 23 May 2022 16:39:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D9BCB6B0073; Mon, 23 May 2022 16:39:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C88976B0074; Mon, 23 May 2022 16:39:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id AE10D6B0072 for ; Mon, 23 May 2022 16:39:55 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id F14D5113E for ; Mon, 23 May 2022 20:01:58 +0000 (UTC) X-FDA: 79498078716.25.698706A Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf16.hostedemail.com (Postfix) with ESMTP id C4CE6180022 for ; Mon, 23 May 2022 20:01:44 +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 0ABA361444; Mon, 23 May 2022 20:01:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 178E0C385AA; Mon, 23 May 2022 20:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653336113; bh=jMzTqIyaDG3t9LHhw88nV+f6YkQIbxRSOEBT5O4w59Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ONhwU75pFeTqbDFN+2WHxoD5qBpE7XhjO44tLF6F+evCgxPliKYlF5BPv8Jv55PCz cO1b2Mh6HupmDzw8lBP/CuvXp1z5r3FHHLGLdpoF0EiqjKOjhbFUWEaVLgS4WVtFgx VftLWMpdyE4iEIFFjtAnNcMi+hh6Gvo1E5ioEuHrqulM+iQQOz6dXAF1QgVSdQbrIW HP4xByVJXF5zn0qUgLF8nB33xEpWLDvton4oZ/gaTcjQ/sBi9d8PbTSX20HOMctWFq zmAO58GboifVYNLrRVvNAlf4dU0mexI0uhBwqMLVXsIYcZxEP8Cgp8EDFXqWIRmVkD 5YC2NpUjClrXQ== Date: Mon, 23 May 2022 23:00:12 +0300 From: Jarkko Sakkinen To: Vasily Averin Cc: Yutian Yang , Shakeel Butt , Michal Hocko , David Howells , Roman Gushchin , cgroups@vger.kernel.org, linux-mm@kvack.org, shenwenbo@zju.edu.cn, Johannes Weiner , kernel@openvz.org Subject: Re: [PATCH] memcg: enable accounting in keyctl subsys Message-ID: References: <1626682667-10771-1-git-send-email-nglaive@gmail.com> <0017e4c6-84d8-6d62-2ceb-4851771fec18@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0017e4c6-84d8-6d62-2ceb-4851771fec18@linux.dev> X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: C4CE6180022 X-Stat-Signature: r3ph4aqyfmma4djzstzpndo3pxfmi83t Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=ONhwU75p; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf16.hostedemail.com: domain of jarkko@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jarkko@kernel.org X-Rspam-User: X-HE-Tag: 1653336104-134715 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: On Mon, May 23, 2022 at 12:45:09PM +0300, Vasily Averin wrote: > On 7/19/21 11:17, Yutian Yang wrote: > > This patch enables accounting for key objects and auth record objects. > > Allocation of the objects are triggerable by syscalls from userspace. > > > > We have written a PoC to show that the missing-charging objects lead to > > breaking memcg limits. The PoC program takes around 2.2GB unaccounted > > memory, while it is charged for only 24MB memory usage. We evaluate the > > PoC on QEMU x86_64 v5.2.90 + Linux kernel v5.10.19 + Debian buster. All > > the limitations including ulimits and sysctl variables are set as default. > > Specifically, we set kernel.keys.maxbytes = 20000 and > > kernel.keys.maxkeys = 200. > > > > /*------------------------- POC code ----------------------------*/ > [skipped] > > /*-------------------------- end --------------------------------*/ > > I experimented with "keyctl request2 user debug: X:Y Z" inside the container > and found that the problem is still relevant and the proposed patch solves it > correctly. > > I didn't find any complaints about this patch, could someone explain why > it wasn't applied? If no one objects, I'd like to push it. > > > Signed-off-by: Yutian Yang > Reviewed-by: Vasily Averin > > Thank you, > Vasily Averin > > PS. Should I perhaps resend it? > > > --- > > security/keys/key.c | 4 ++-- > > security/keys/request_key_auth.c | 4 ++-- > > 2 files changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/security/keys/key.c b/security/keys/key.c > > index e282c6179..925d85c2e 100644 > > --- a/security/keys/key.c > > +++ b/security/keys/key.c > > @@ -279,7 +279,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, > > goto no_memory_2; > > > > key->index_key.desc_len = desclen; > > - key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL); > > + key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL_ACCOUNT); > > if (!key->index_key.description) > > goto no_memory_3; > > key->index_key.type = type; > > @@ -1198,7 +1198,7 @@ void __init key_init(void) > > { > > /* allocate a slab in which we can store keys */ > > key_jar = kmem_cache_create("key_jar", sizeof(struct key), > > - 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); > > + 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL); > > > > /* add the special key types */ > > list_add_tail(&key_type_keyring.link, &key_types_list); > > diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c > > index 41e973500..ed50a100a 100644 > > --- a/security/keys/request_key_auth.c > > +++ b/security/keys/request_key_auth.c > > @@ -171,10 +171,10 @@ struct key *request_key_auth_new(struct key *target, const char *op, > > kenter("%d,", target->serial); > > > > /* allocate a auth record */ > > - rka = kzalloc(sizeof(*rka), GFP_KERNEL); > > + rka = kzalloc(sizeof(*rka), GFP_KERNEL_ACCOUNT); > > if (!rka) > > goto error; > > - rka->callout_info = kmemdup(callout_info, callout_len, GFP_KERNEL); > > + rka->callout_info = kmemdup(callout_info, callout_len, GFP_KERNEL_ACCOUNT); > > if (!rka->callout_info) > > goto error_free_rka; > > rka->callout_len = callout_len; > Acked-by: Jarkko Sakkinen BR, Jarkko