From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755322AbbBBKHK (ORCPT ); Mon, 2 Feb 2015 05:07:10 -0500 Received: from mail-la0-f43.google.com ([209.85.215.43]:43736 "EHLO mail-la0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933079AbbBBKHC (ORCPT ); Mon, 2 Feb 2015 05:07:02 -0500 From: Ricardo Ribalda Delgado To: Mark Brown , Michal Simek , =?UTF-8?q?S=C3=B6ren=20Brinkmann?= , linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Ricardo Ribalda Delgado Subject: [PATCH v2] spi/xilinx: Fix access invalid memory on xilinx_spi_tx Date: Mon, 2 Feb 2015 11:06:56 +0100 Message-Id: <1422871616-6686-1-git-send-email-ricardo.ribalda@gmail.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1 and 2 bytes per word, the transfer of the 3 last bytes will access memory outside tx_ptr. Although this has not trigger any error on real hardware, we should better fix this. Fixes: 24ba5e593f391507 Remove rx_fn and tx_fn pointer Signed-off-by: Ricardo Ribalda Delgado --- v2: v1 was completely wrong, sorry about that :(. This v2 has been tested on x86 1 byte per word drivers/spi/spi-xilinx.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index d1901d5..133f53a 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -117,11 +117,26 @@ static unsigned int xspi_read32_be(void __iomem *addr) static void xilinx_spi_tx(struct xilinx_spi *xspi) { + u32 data = 0; + if (!xspi->tx_ptr) { xspi->write_fn(0, xspi->regs + XSPI_TXD_OFFSET); return; } - xspi->write_fn(*(u32 *)(xspi->tx_ptr), xspi->regs + XSPI_TXD_OFFSET); + + switch (xspi->bytes_per_word) { + case 1: + data = *(u8 *)(xspi->tx_ptr); + break; + case 2: + data = *(u16 *)(xspi->tx_ptr); + break; + case 4: + data = *(u32 *)(xspi->tx_ptr); + break; + } + + xspi->write_fn(data, xspi->regs + XSPI_TXD_OFFSET); xspi->tx_ptr += xspi->bytes_per_word; } -- 2.1.4