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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 186AAC43381 for ; Mon, 25 Feb 2019 21:29:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D03392084D for ; Mon, 25 Feb 2019 21:29:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551130140; bh=RMyL8iQ0MkUykazmYHPjJScq5vPO8M77C8/pB+tmff4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yVVksBt850hrs+Tm8Y8oeYrrLZ3giYAq/AEnl+c02x6z3KhipbNQqFqKTr6H6BBTd dK2piMncix+Gv4quDVD/5my+8rh3ENKFaemJqEmpiYps2f5dHxjHbxHrtO23cSQuL9 LqIYCKVPlN86lM1X6Yl3XLykrnYf4zCkaBxYZL0Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731949AbfBYV26 (ORCPT ); Mon, 25 Feb 2019 16:28:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:34754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731933AbfBYV25 (ORCPT ); Mon, 25 Feb 2019 16:28:57 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 085A820C01; Mon, 25 Feb 2019 21:28:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551130136; bh=RMyL8iQ0MkUykazmYHPjJScq5vPO8M77C8/pB+tmff4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=blYTaoks2KBuoLkqHX7iJTBBRHb1mHfc1iPMhAE4FdSsOsNF3n1GpX4HPaGWqF2Pc vJjrQ5z4vSU+jIdKoHcVFQ0dO5xPeTs4/UF1+ISf6mQ7/kKT4Mc7rTFkYIYK+v5fQF uU8kukmNP2q7KblrfSyZJV0bImYn+NBIuuFRvlkk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , David Howells , James Morris Subject: [PATCH 4.20 018/183] KEYS: allow reaching the keys quotas exactly Date: Mon, 25 Feb 2019 22:09:51 +0100 Message-Id: <20190225195057.803846332@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190225195054.748060397@linuxfoundation.org> References: <20190225195054.748060397@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers commit a08bf91ce28ed3ae7b6fef35d843fef8dc8c2cd9 upstream. If the sysctl 'kernel.keys.maxkeys' is set to some number n, then actually users can only add up to 'n - 1' keys. Likewise for 'kernel.keys.maxbytes' and the root_* versions of these sysctls. But these sysctls are apparently supposed to be *maximums*, as per their names and all documentation I could find -- the keyrings(7) man page, Documentation/security/keys/core.rst, and all the mentions of EDQUOT meaning that the key quota was *exceeded* (as opposed to reached). Thus, fix the code to allow reaching the quotas exactly. Fixes: 0b77f5bfb45c ("keys: make the keyring quotas controllable through /proc/sys") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: David Howells Signed-off-by: James Morris Signed-off-by: Greg Kroah-Hartman --- security/keys/key.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/security/keys/key.c +++ b/security/keys/key.c @@ -265,8 +265,8 @@ struct key *key_alloc(struct key_type *t spin_lock(&user->lock); if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { - if (user->qnkeys + 1 >= maxkeys || - user->qnbytes + quotalen >= maxbytes || + if (user->qnkeys + 1 > maxkeys || + user->qnbytes + quotalen > maxbytes || user->qnbytes + quotalen < user->qnbytes) goto no_quota; }