From patchwork Tue Feb 28 16:28:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Keller X-Patchwork-Id: 657715 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 4E3ADC64EC7 for ; Tue, 28 Feb 2023 16:29:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229574AbjB1Q27 (ORCPT ); Tue, 28 Feb 2023 11:28:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229509AbjB1Q26 (ORCPT ); Tue, 28 Feb 2023 11:28:58 -0500 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BD70F97B for ; Tue, 28 Feb 2023 08:28:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1677601714; x=1709137714; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=3IUiuQDXLWHfaTHU14YJHaMpCG6zn1yfzHLbH9QGLlg=; b=E5hHnAdn0MDWaijKGpC8fn4sUBAOFdlwzFpisJ3pOFEHk32ff7eaPIDb SM6bywoCtqVxggYHxr8RLYEYevqsnQmwHqUPbowzpyY9AlAsCLX2FNYkP sTbfEt0aBr0yokONcJAaEcDHbRnGaB7uPGEJwVviHlfIVNeZDppjBIfVl YqYjsJVxZOh8kMhm6jW2+aShYrOkSkYtCBRWGk2UFggG85s0HqwV8Zbu3 BwhfySh1YJzcRuK/M7nrrm55CX93rDNgDozgHj6+4uSRXBbAPX8HQFE/E SPB28cJVeHSAmCLlE/ymHRsnTDGJtIoVwchXXxNODEjvb9X2uJGi2joKK Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10635"; a="398964470" X-IronPort-AV: E=Sophos;i="5.98,222,1673942400"; d="scan'208";a="398964470" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Feb 2023 08:28:33 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10635"; a="676361737" X-IronPort-AV: E=Sophos;i="5.98,222,1673942400"; d="scan'208";a="676361737" Received: from jekeller-desk.amr.corp.intel.com (HELO jekeller-desk.jekeller.internal) ([10.166.241.1]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Feb 2023 08:28:32 -0800 From: Jacob Keller To: Johannes Berg Cc: Kalle Valo , linux-wireless@vger.kernel.org, Jacob Keller , Stanislav Yakovlev Subject: [PATCH 1/3] wifi: ipw2x00: convert ipw_fw_error->elem to flexible array[] Date: Tue, 28 Feb 2023 08:28:25 -0800 Message-Id: <20230228162827.3876606-1-jacob.e.keller@intel.com> X-Mailer: git-send-email 2.39.1.405.gd4c25cc71f83 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org The ipw_fw_error structure contains a payload[] flexible array as well as two pointers to this array area, ->elem, and ->log. The total size of the allocated structure is computed without use of the macros. There's no reason to keep both a payload[] and an extra pointer to both the elem and log members. Convert the elem pointer member into the flexible array member, removing payload. Fix the allocation of the ipw_fw_error structure to use size_add(), struct_size(), and array_size() to compute the allocation. This ensures that any overflow saturates at SIZE_MAX rather than overflowing and potentially allowing an undersized allocation. Before the structure change, the layout of ipw_fw_error was: struct ipw_fw_error { long unsigned int jiffies; /* 0 8 */ u32 status; /* 8 4 */ u32 config; /* 12 4 */ u32 elem_len; /* 16 4 */ u32 log_len; /* 20 4 */ struct ipw_error_elem * elem; /* 24 8 */ struct ipw_event * log; /* 32 8 */ u8 payload[]; /* 40 0 */ /* size: 40, cachelines: 1, members: 8 */ /* last cacheline: 40 bytes */ }; After this change, the layout is now: struct ipw_fw_error { long unsigned int jiffies; /* 0 8 */ u32 status; /* 8 4 */ u32 config; /* 12 4 */ u32 elem_len; /* 16 4 */ u32 log_len; /* 20 4 */ struct ipw_event * log; /* 24 8 */ struct ipw_error_elem elem[]; /* 32 0 */ /* size: 32, cachelines: 1, members: 7 */ /* last cacheline: 32 bytes */ }; This saves a total of 8 bytes for every ipw_fw_error allocation, and removes the risk of a potential overflow on the allocation. Signed-off-by: Jacob Keller Cc: Stanislav Yakovlev --- drivers/net/wireless/intel/ipw2x00/ipw2200.c | 7 +++---- drivers/net/wireless/intel/ipw2x00/ipw2200.h | 3 +-- 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/intel/ipw2x00/ipw2200.c b/drivers/net/wireless/intel/ipw2x00/ipw2200.c index d382f2017325..b91b1a2d0be7 100644 --- a/drivers/net/wireless/intel/ipw2x00/ipw2200.c +++ b/drivers/net/wireless/intel/ipw2x00/ipw2200.c @@ -1234,9 +1234,9 @@ static struct ipw_fw_error *ipw_alloc_error_log(struct ipw_priv *priv) u32 base = ipw_read32(priv, IPW_ERROR_LOG); u32 elem_len = ipw_read_reg32(priv, base); - error = kmalloc(sizeof(*error) + - sizeof(*error->elem) * elem_len + - sizeof(*error->log) * log_len, GFP_ATOMIC); + error = kmalloc(size_add(struct_size(error, elem, elem_len), + array_size(sizeof(*error->log), log_len)), + GFP_ATOMIC); if (!error) { IPW_ERROR("Memory allocation for firmware error log " "failed.\n"); @@ -1247,7 +1247,6 @@ static struct ipw_fw_error *ipw_alloc_error_log(struct ipw_priv *priv) error->config = priv->config; error->elem_len = elem_len; error->log_len = log_len; - error->elem = (struct ipw_error_elem *)error->payload; error->log = (struct ipw_event *)(error->elem + elem_len); ipw_capture_event_log(priv, log_len, error->log); diff --git a/drivers/net/wireless/intel/ipw2x00/ipw2200.h b/drivers/net/wireless/intel/ipw2x00/ipw2200.h index 09ddd21608d4..8ebf09121e17 100644 --- a/drivers/net/wireless/intel/ipw2x00/ipw2200.h +++ b/drivers/net/wireless/intel/ipw2x00/ipw2200.h @@ -1106,9 +1106,8 @@ struct ipw_fw_error { /* XXX */ u32 config; u32 elem_len; u32 log_len; - struct ipw_error_elem *elem; struct ipw_event *log; - u8 payload[]; + struct ipw_error_elem elem[]; } __packed; #ifdef CONFIG_IPW2200_PROMISCUOUS