From patchwork Mon May 17 11:59:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 12261713 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B487AC43461 for ; Mon, 17 May 2021 11:58:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 941436101E for ; Mon, 17 May 2021 11:58:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236882AbhEQMAG (ORCPT ); Mon, 17 May 2021 08:00:06 -0400 Received: from mga02.intel.com ([134.134.136.20]:47948 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236866AbhEQMAE (ORCPT ); Mon, 17 May 2021 08:00:04 -0400 IronPort-SDR: cOVUxS+T11GfOVcRpTUlKvrjOhUNjcgTsbQgnRc1iVqClzoD09c9UETG0FN10Gp+qpGsSo2GM3 tLVCgIY3uf5g== X-IronPort-AV: E=McAfee;i="6200,9189,9986"; a="187568069" X-IronPort-AV: E=Sophos;i="5.82,307,1613462400"; d="scan'208";a="187568069" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 May 2021 04:58:48 -0700 IronPort-SDR: QCrjwCxw8KrarigGQCP1MFBm+C/G058AvAjqMXjjG9thwmxr0W59b7ht6AGaEJOo/3t0vfD4Jt UEjNUMp8Um/Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,307,1613462400"; d="scan'208";a="393487065" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga003.jf.intel.com with ESMTP; 17 May 2021 04:58:46 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id 6C7FB50E; Mon, 17 May 2021 14:59:07 +0300 (EEST) From: Mika Westerberg To: linux-usb@vger.kernel.org Cc: Yehezkel Bernat , Michael Jamet , Andreas Noever , Mathias Nyman , Lukas Wunner , Mika Westerberg Subject: [PATCH 2/4] thunderbolt: usb4: Fix NVM read buffer bounds and offset issue Date: Mon, 17 May 2021 14:59:05 +0300 Message-Id: <20210517115907.52503-3-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210517115907.52503-1-mika.westerberg@linux.intel.com> References: <20210517115907.52503-1-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: Mathias Nyman Up to 64 bytes of data can be read from NVM in one go. Read address must be dword aligned. Data is read into a local buffer. If caller asks to read data starting at an unaligned address then full dword is anyway read from NVM into a local buffer. Data is then copied from the local buffer starting at the unaligned offset to the caller buffer. In cases where asked data length + unaligned offset is over 64 bytes we need to make sure we don't read past the 64 bytes in the local buffer when copying to caller buffer, and make sure that we don't skip copying unaligned offset bytes from local buffer anymore after the first round of 64 byte NVM data read. Fixes: b04079837b20 ("thunderbolt: Add initial support for USB4") Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman Signed-off-by: Mika Westerberg --- drivers/thunderbolt/usb4.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 680bc738dd66..671d72af8ba1 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -68,15 +68,15 @@ static int usb4_do_read_data(u16 address, void *buf, size_t size, unsigned int retries = USB4_DATA_RETRIES; unsigned int offset; - offset = address & 3; - address = address & ~3; - do { - size_t nbytes = min_t(size_t, size, USB4_DATA_DWORDS * 4); unsigned int dwaddress, dwords; u8 data[USB4_DATA_DWORDS * 4]; + size_t nbytes; int ret; + offset = address & 3; + nbytes = min_t(size_t, size + offset, USB4_DATA_DWORDS * 4); + dwaddress = address / 4; dwords = ALIGN(nbytes, 4) / 4; @@ -87,6 +87,7 @@ static int usb4_do_read_data(u16 address, void *buf, size_t size, return ret; } + nbytes -= offset; memcpy(buf, data + offset, nbytes); size -= nbytes;