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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 42CCCC83F1A for ; Mon, 28 Aug 2023 10:29:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231294AbjH1K2k (ORCPT ); Mon, 28 Aug 2023 06:28:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231398AbjH1K2Z (ORCPT ); Mon, 28 Aug 2023 06:28:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 980BB188 for ; Mon, 28 Aug 2023 03:28:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2919663BA6 for ; Mon, 28 Aug 2023 10:28:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A812C433C7; Mon, 28 Aug 2023 10:28:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693218496; bh=lIm294P96tKTS6a7bmExhWG++JL5QGvJdxq1fiER1Vc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v5NuzS6J1QXLscmsZIycnpwxQcGCGegstZ07VKm8GgDaYxp6OZ7zwu8tykhcq/oPw dhv4rfgdScNDWtr9JNd/eIaRGxVe04Uj5rwGFf3FQwUwSVYBrI6jbMIFeeQi2tzKt5 2fCNrMXz53fMNAKlQLZzSfMQUkCgLQPI+fjaRMQA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Junwei Hu , Julian Anastasov , Pablo Neira Ayuso Subject: [PATCH 4.19 108/129] ipvs: Improve robustness to the ipvs sysctl Date: Mon, 28 Aug 2023 12:13:22 +0200 Message-ID: <20230828101157.203285165@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230828101153.030066927@linuxfoundation.org> References: <20230828101153.030066927@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Junwei Hu commit 1b90af292e71b20d03b837d39406acfbdc5d4b2a upstream. The ipvs module parse the user buffer and save it to sysctl, then check if the value is valid. invalid value occurs over a period of time. Here, I add a variable, struct ctl_table tmp, used to read the value from the user buffer, and save only when it is valid. I delete proc_do_sync_mode and use extra1/2 in table for the proc_dointvec_minmax call. Fixes: f73181c8288f ("ipvs: add support for sync threads") Signed-off-by: Junwei Hu Acked-by: Julian Anastasov Signed-off-by: Pablo Neira Ayuso [Julian: Backport by changing SYSCTL_ZERO/SYSCTL_ONE to zero/one] Signed-off-by: Julian Anastasov Signed-off-by: Greg Kroah-Hartman --- net/netfilter/ipvs/ip_vs_ctl.c | 70 +++++++++++++++++++++-------------------- 1 file changed, 36 insertions(+), 34 deletions(-) --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -1656,6 +1656,7 @@ static int ip_vs_zero_all(struct netns_i #ifdef CONFIG_SYSCTL static int zero; +static int one = 1; static int three = 3; static int @@ -1667,12 +1668,18 @@ proc_do_defense_mode(struct ctl_table *t int val = *valp; int rc; - rc = proc_dointvec(table, write, buffer, lenp, ppos); + struct ctl_table tmp = { + .data = &val, + .maxlen = sizeof(int), + .mode = table->mode, + }; + + rc = proc_dointvec(&tmp, write, buffer, lenp, ppos); if (write && (*valp != val)) { - if ((*valp < 0) || (*valp > 3)) { - /* Restore the correct value */ - *valp = val; + if (val < 0 || val > 3) { + rc = -EINVAL; } else { + *valp = val; update_defense_level(ipvs); } } @@ -1686,33 +1693,20 @@ proc_do_sync_threshold(struct ctl_table int *valp = table->data; int val[2]; int rc; + struct ctl_table tmp = { + .data = &val, + .maxlen = table->maxlen, + .mode = table->mode, + }; - /* backup the value first */ memcpy(val, valp, sizeof(val)); - - rc = proc_dointvec(table, write, buffer, lenp, ppos); - if (write && (valp[0] < 0 || valp[1] < 0 || - (valp[0] >= valp[1] && valp[1]))) { - /* Restore the correct value */ - memcpy(valp, val, sizeof(val)); - } - return rc; -} - -static int -proc_do_sync_mode(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int *valp = table->data; - int val = *valp; - int rc; - - rc = proc_dointvec(table, write, buffer, lenp, ppos); - if (write && (*valp != val)) { - if ((*valp < 0) || (*valp > 1)) { - /* Restore the correct value */ - *valp = val; - } + rc = proc_dointvec(&tmp, write, buffer, lenp, ppos); + if (write) { + if (val[0] < 0 || val[1] < 0 || + (val[0] >= val[1] && val[1])) + rc = -EINVAL; + else + memcpy(valp, val, sizeof(val)); } return rc; } @@ -1725,12 +1719,18 @@ proc_do_sync_ports(struct ctl_table *tab int val = *valp; int rc; - rc = proc_dointvec(table, write, buffer, lenp, ppos); + struct ctl_table tmp = { + .data = &val, + .maxlen = sizeof(int), + .mode = table->mode, + }; + + rc = proc_dointvec(&tmp, write, buffer, lenp, ppos); if (write && (*valp != val)) { - if (*valp < 1 || !is_power_of_2(*valp)) { - /* Restore the correct value */ + if (val < 1 || !is_power_of_2(val)) + rc = -EINVAL; + else *valp = val; - } } return rc; } @@ -1790,7 +1790,9 @@ static struct ctl_table vs_vars[] = { .procname = "sync_version", .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_do_sync_mode, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, { .procname = "sync_ports",