From patchwork Fri Jul 28 15:52:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 13332085 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 090FAC001DE for ; Fri, 28 Jul 2023 15:53:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236657AbjG1Pxk (ORCPT ); Fri, 28 Jul 2023 11:53:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236168AbjG1Pxj (ORCPT ); Fri, 28 Jul 2023 11:53:39 -0400 Received: from mgamail.intel.com (unknown [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 424743C1D; Fri, 28 Jul 2023 08:53:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1690559618; x=1722095618; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=k9V2394RCtvh3NTAt2WTSve+1zGj0J3twZowpzpftjU=; b=AjtlS8echpEDxlMtTtimGySWpAIqg8nQR7u67fD7OhPDZJiepkovxee3 pfjCx2Lss/re/+P8VokcQmnPNz9F/pJWo+dzVMd/ZMO/BTpJbpyRHkLw/ ZtU/or1co6xvrw2HDKcgC5CV6GrXwiUv/Gg6uEuSZxiPBvVLhGzrxi5qS YfMQphUK4TR8eH8l85t6MExGzV7vgwMFr0jS5mxL5jSIYNymC9y0T3llV rNfoDLTHddhaoSSNNI5iVW+RKRxk2DZ0CzeCKRIkQQZVvOp4WluNCf5eh SpIi1d/H3cutXzFuNlVUnu6Q2GMbhvUMMFC/MNKmi/SEfeK8bklWwgNC+ g==; X-IronPort-AV: E=McAfee;i="6600,9927,10784"; a="372246663" X-IronPort-AV: E=Sophos;i="6.01,237,1684825200"; d="scan'208";a="372246663" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jul 2023 08:53:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10784"; a="727512165" X-IronPort-AV: E=Sophos;i="6.01,237,1684825200"; d="scan'208";a="727512165" Received: from newjersey.igk.intel.com ([10.102.20.203]) by orsmga002.jf.intel.com with ESMTP; 28 Jul 2023 08:53:34 -0700 From: Alexander Lobakin To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Alexander Lobakin , Larysa Zaremba , Andy Shevchenko , "Gustavo A. R. Silva" , Kees Cook , netdev@vger.kernel.org, linux-hardening@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-kernel@vger.kernel.org Subject: [PATCH net-next 1/3] virtchnl: fix fake 1-elem arrays in structs allocated as `nents + 1` - 1 Date: Fri, 28 Jul 2023 17:52:05 +0200 Message-ID: <20230728155207.10042-2-aleksander.lobakin@intel.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230728155207.10042-1-aleksander.lobakin@intel.com> References: <20230728155207.10042-1-aleksander.lobakin@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org The two most problematic virtchnl structures are virtchnl_rss_key and virtchnl_rss_lut. Their "flex" arrays have the type of u8, thus, when allocating / checking, the actual size is calculated as `sizeof + nents - 1 byte`. But their sizeof() is not 1 byte larger than the size of such structure with proper flex array, it's two bytes larger due to the padding. That said, their size is always 1 byte larger unless there are no tail elements -- then it's +2 bytes. Add virtchnl_struct_size() macro which will handle this case (and later other cases as well). Make its calling conv the same as we call struct_size() to allow it to be drop-in, even though it's unlikely to become possible to switch to generic API. The macro will calculate a proper size of a structure with a flex array at the end, so that it becomes transparent for the compilers, but add the difference from the old values, so that the real size of sorta-ABI-messages doesn't change. Use it on the allocation side in IAVF and the receiving side (defined as static inline in virtchnl.h) for the mentioned two structures. Signed-off-by: Alexander Lobakin Reviewed-by: Kees Cook Tested-by: Rafal Romanowski --- .../net/ethernet/intel/iavf/iavf_virtchnl.c | 6 ++-- include/linux/avf/virtchnl.h | 31 ++++++++++++++----- 2 files changed, 25 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c index be3c007ce90a..10f03054a603 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c +++ b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c @@ -1085,8 +1085,7 @@ void iavf_set_rss_key(struct iavf_adapter *adapter) adapter->current_op); return; } - len = sizeof(struct virtchnl_rss_key) + - (adapter->rss_key_size * sizeof(u8)) - 1; + len = virtchnl_struct_size(vrk, key, adapter->rss_key_size); vrk = kzalloc(len, GFP_KERNEL); if (!vrk) return; @@ -1117,8 +1116,7 @@ void iavf_set_rss_lut(struct iavf_adapter *adapter) adapter->current_op); return; } - len = sizeof(struct virtchnl_rss_lut) + - (adapter->rss_lut_size * sizeof(u8)) - 1; + len = virtchnl_struct_size(vrl, lut, adapter->rss_lut_size); vrl = kzalloc(len, GFP_KERNEL); if (!vrl) return; diff --git a/include/linux/avf/virtchnl.h b/include/linux/avf/virtchnl.h index c15221dcb75e..3ab207c14809 100644 --- a/include/linux/avf/virtchnl.h +++ b/include/linux/avf/virtchnl.h @@ -866,18 +866,20 @@ VIRTCHNL_CHECK_STRUCT_LEN(4, virtchnl_promisc_info); struct virtchnl_rss_key { u16 vsi_id; u16 key_len; - u8 key[1]; /* RSS hash key, packed bytes */ + u8 key[]; /* RSS hash key, packed bytes */ }; -VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key); +VIRTCHNL_CHECK_STRUCT_LEN(4, virtchnl_rss_key); +#define virtchnl_rss_key_LEGACY_SIZEOF 6 struct virtchnl_rss_lut { u16 vsi_id; u16 lut_entries; - u8 lut[1]; /* RSS lookup table */ + u8 lut[]; /* RSS lookup table */ }; -VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut); +VIRTCHNL_CHECK_STRUCT_LEN(4, virtchnl_rss_lut); +#define virtchnl_rss_lut_LEGACY_SIZEOF 6 /* VIRTCHNL_OP_GET_RSS_HENA_CAPS * VIRTCHNL_OP_SET_RSS_HENA @@ -1367,6 +1369,17 @@ struct virtchnl_fdir_del { VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_fdir_del); +#define __vss_byone(p, member, count, old) \ + (struct_size(p, member, count) + (old - 1 - struct_size(p, member, 0))) + +#define __vss(type, func, p, member, count) \ + struct type: func(p, member, count, type##_LEGACY_SIZEOF) + +#define virtchnl_struct_size(p, m, c) \ + _Generic(*p, \ + __vss(virtchnl_rss_key, __vss_byone, p, m, c), \ + __vss(virtchnl_rss_lut, __vss_byone, p, m, c)) + /** * virtchnl_vc_validate_vf_msg * @ver: Virtchnl version info @@ -1479,19 +1492,21 @@ virtchnl_vc_validate_vf_msg(struct virtchnl_version_info *ver, u32 v_opcode, } break; case VIRTCHNL_OP_CONFIG_RSS_KEY: - valid_len = sizeof(struct virtchnl_rss_key); + valid_len = virtchnl_rss_key_LEGACY_SIZEOF; if (msglen >= valid_len) { struct virtchnl_rss_key *vrk = (struct virtchnl_rss_key *)msg; - valid_len += vrk->key_len - 1; + valid_len = virtchnl_struct_size(vrk, key, + vrk->key_len); } break; case VIRTCHNL_OP_CONFIG_RSS_LUT: - valid_len = sizeof(struct virtchnl_rss_lut); + valid_len = virtchnl_rss_lut_LEGACY_SIZEOF; if (msglen >= valid_len) { struct virtchnl_rss_lut *vrl = (struct virtchnl_rss_lut *)msg; - valid_len += vrl->lut_entries - 1; + valid_len = virtchnl_struct_size(vrl, lut, + vrl->lut_entries); } break; case VIRTCHNL_OP_GET_RSS_HENA_CAPS: