From mboxrd@z Thu Jan 1 00:00:00 1970 From: Harry Zhang Subject: libahci: Fix bug in storing EM messages Date: Fri, 11 Jun 2010 15:44:12 +0800 Message-ID: <1276242252.14959.8.camel@zm-desktop> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from tx2ehsobe003.messaging.microsoft.com ([65.55.88.13]:10842 "EHLO TX2EHSOBE005.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752969Ab0FKHrh (ORCPT ); Fri, 11 Jun 2010 03:47:37 -0400 Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: jgarzik@pobox.com Cc: linux-ide@vger.kernel.org, tj@kernel.org, shane.huang@amd.com, Zhang@domain.invalid, Harry In function ahci_store_em_buffer(), if the input (signed char*) buffer contains negative data, the constructed 32-bit long message data may be wrong. Signed-off-by: Harry Zhang --- drivers/ata/libahci.c | 9 +++------ 1 files changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index 1984a6e..09a9b51 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -324,7 +324,7 @@ static ssize_t ahci_store_em_buffer(struct device *dev, struct ahci_host_priv *hpriv = ap->host->private_data; void __iomem *mmio = hpriv->mmio; void __iomem *em_mmio = mmio + hpriv->em_loc; - u32 em_ctl, msg; + u32 em_ctl, *msg_buf = (u32 *)buf; unsigned long flags; int i; @@ -342,11 +342,8 @@ static ssize_t ahci_store_em_buffer(struct device *dev, return -EBUSY; } - for (i = 0; i < size; i += 4) { - msg = buf[i] | buf[i + 1] << 8 | - buf[i + 2] << 16 | buf[i + 3] << 24; - writel(msg, em_mmio + i); - } + for (i = 0; i < size; i += 4) + writel(msg_buf[i >> 2], em_mmio + i); writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL); -- 1.6.4.2