From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 92EDA1AA61 for ; Wed, 16 Aug 2023 21:14:03 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 495BEE4F for ; Wed, 16 Aug 2023 14:14:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1692220441; x=1723756441; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Gplscp/XZkhuKoy/2Rvmy5zxnyy+eYc3CmlmBUferVA=; b=e5Yc3gQZrOOHAs3iVBDDKPFD3QkCeKE1fkARanLRrbuazo+Q/+rdvYGn DtSffoNrDzHXudtf2ZuHELLAuAEVHCF4jnx4AVbx3v24gOqg8zr1Azppg J2wLTnCaUiTYQEhzRO4ABKUL9YQXQLAThRjNNZVGZz7kYZiL2nqdVStVq GVA9I45dKBpkFn3YgVUUfAfXKk0c8Qbfu6TrU+vrK4t1LAK8R1Rsj6GEb yUE9I35GVwemzWqB2eR92Ur6WQVZvdLoSME15WMLcL5f5xb5dTjk+dtH7 +ATGEmBqzFWWCnr6p+1mBFGwBPHiPhGgfdAWDa+YasRsz1BYdPXDmXkT7 g==; X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="352223490" X-IronPort-AV: E=Sophos;i="6.01,178,1684825200"; d="scan'208";a="352223490" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2023 14:13:56 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="763765534" X-IronPort-AV: E=Sophos;i="6.01,178,1684825200"; d="scan'208";a="763765534" Received: from anguy11-upstream.jf.intel.com ([10.166.9.133]) by orsmga008.jf.intel.com with ESMTP; 16 Aug 2023 14:13:56 -0700 From: Tony Nguyen To: davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, netdev@vger.kernel.org Cc: Alexander Lobakin , anthony.l.nguyen@intel.com, andriy.shevchenko@linux.intel.com, larysa.zaremba@intel.com, keescook@chromium.org, gustavoars@kernel.org, Rafal Romanowski Subject: [PATCH net-next 1/3] virtchnl: fix fake 1-elem arrays in structs allocated as `nents + 1` - 1 Date: Wed, 16 Aug 2023 14:06:55 -0700 Message-Id: <20230816210657.1326772-2-anthony.l.nguyen@intel.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20230816210657.1326772-1-anthony.l.nguyen@intel.com> References: <20230816210657.1326772-1-anthony.l.nguyen@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net From: Alexander Lobakin 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 Signed-off-by: Tony Nguyen --- .../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: -- 2.38.1