From nobody Fri Feb 13 09:31:11 2026 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 08E6EE7F150 for ; Wed, 27 Sep 2023 02:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234838AbjI0Cjz (ORCPT ); Tue, 26 Sep 2023 22:39:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233436AbjI0Chv (ORCPT ); Tue, 26 Sep 2023 22:37:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F1631C26B; Tue, 26 Sep 2023 19:02:55 -0700 (PDT) X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="385565342" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="385565342" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Sep 2023 19:02:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="725628836" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="725628836" Received: from pinksteam.jf.intel.com ([10.165.239.231]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Sep 2023 19:02:39 -0700 From: joao@overdrivepizza.com To: pablo@netfilter.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, joao@overdrivepizza.com Cc: kadlec@netfilter.org, fw@strlen.de, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, rkannoth@marvell.com, wojciech.drewek@intel.com, steen.hegenlund@microhip.com, keescook@chromium.org, Joao Moreira Subject: [PATCH v2 1/2] Make loop indexes unsigned Date: Tue, 26 Sep 2023 19:02:20 -0700 Message-ID: <20230927020221.85292-2-joao@overdrivepizza.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230927020221.85292-1-joao@overdrivepizza.com> References: <20230927020221.85292-1-joao@overdrivepizza.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Joao Moreira Both flow_rule_alloc and offload_action_alloc functions received an unsigned num_actions parameters which are then operated within a loop. The index of this loop is declared as a signed int. If it was possible to pass a large enough num_actions to these functions, it would lead to an out of bounds write. After checking with maintainers, it was mentioned that front-end will cap the num_actions value and that it is not possible to reach this function with such a large number. Yet, for correctness, it is still better to fix this. This issue was observed by the commit author while reviewing a write-up regarding a CVE within the same subsystem [1]. 1 - https://nickgregory.me/post/2022/03/12/cve-2022-25636/ Signed-off-by: Joao Moreira --- net/core/flow_offload.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c index bc5169482710..bc3f53a09d8f 100644 --- a/net/core/flow_offload.c +++ b/net/core/flow_offload.c @@ -10,7 +10,7 @@ struct flow_rule *flow_rule_alloc(unsigned int num_actions) { struct flow_rule *rule; - int i; + unsigned int i; =20 rule =3D kzalloc(struct_size(rule, action.entries, num_actions), GFP_KERNEL); @@ -31,7 +31,7 @@ EXPORT_SYMBOL(flow_rule_alloc); struct flow_offload_action *offload_action_alloc(unsigned int num_actions) { struct flow_offload_action *fl_action; - int i; + unsigned int i; =20 fl_action =3D kzalloc(struct_size(fl_action, action.entries, num_actions), GFP_KERNEL); --=20 2.42.0 From nobody Fri Feb 13 09:31:11 2026 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 8B72DE7F14B for ; Wed, 27 Sep 2023 02:39:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234743AbjI0Cjx (ORCPT ); Tue, 26 Sep 2023 22:39:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229499AbjI0Chv (ORCPT ); Tue, 26 Sep 2023 22:37:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21CDE1C26C; Tue, 26 Sep 2023 19:02:56 -0700 (PDT) X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="385565355" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="385565355" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Sep 2023 19:02:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="725628857" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="725628857" Received: from pinksteam.jf.intel.com ([10.165.239.231]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Sep 2023 19:02:41 -0700 From: joao@overdrivepizza.com To: pablo@netfilter.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, joao@overdrivepizza.com Cc: kadlec@netfilter.org, fw@strlen.de, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, rkannoth@marvell.com, wojciech.drewek@intel.com, steen.hegenlund@microhip.com, keescook@chromium.org, Joao Moreira Subject: [PATCH v2 2/2] Make num_actions unsigned Date: Tue, 26 Sep 2023 19:02:21 -0700 Message-ID: <20230927020221.85292-3-joao@overdrivepizza.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230927020221.85292-1-joao@overdrivepizza.com> References: <20230927020221.85292-1-joao@overdrivepizza.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Joao Moreira Currently, in nft_flow_rule_create function, num_actions is a signed integer. Yet, it is processed within a loop which increments its value. To prevent an overflow from occurring, make it unsigned and also check if it reaches UINT_MAX when being incremented. After checking with maintainers, it was mentioned that front-end will cap the num_actions value and that it is not possible to reach such condition for an overflow. Yet, for correctness, it is still better to fix this. This issue was observed by the commit author while reviewing a write-up regarding a CVE within the same subsystem [1]. 1 - https://nickgregory.me/post/2022/03/12/cve-2022-25636/ Signed-off-by: Joao Moreira --- net/netfilter/nf_tables_offload.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_of= fload.c index 12ab78fa5d84..d25088791a74 100644 --- a/net/netfilter/nf_tables_offload.c +++ b/net/netfilter/nf_tables_offload.c @@ -90,7 +90,8 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *ne= t, { struct nft_offload_ctx *ctx; struct nft_flow_rule *flow; - int num_actions =3D 0, err; + unsigned int num_actions =3D 0; + int err; struct nft_expr *expr; =20 expr =3D nft_expr_first(rule); @@ -99,6 +100,9 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *n= et, expr->ops->offload_action(expr)) num_actions++; =20 + if (num_actions =3D=3D UINT_MAX) + return ERR_PTR(-ENOMEM); + expr =3D nft_expr_next(expr); } =20 --=20 2.42.0