From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933506AbbCFKD2 (ORCPT ); Fri, 6 Mar 2015 05:03:28 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44927 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933328AbbCFKBW (ORCPT ); Fri, 6 Mar 2015 05:01:22 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Dan Carpenter , Nicholas Bellinger , Luis Henriques Subject: [PATCH 3.16.y-ckt 174/183] vhost/scsi: potential memory corruption Date: Fri, 6 Mar 2015 09:57:45 +0000 Message-Id: <1425635874-19087-175-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> References: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt8 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 59c816c1f24df0204e01851431d3bab3eb76719c upstream. This code in vhost_scsi_make_tpg() is confusing because we limit "tpgt" to UINT_MAX but the data type of "tpg->tport_tpgt" and that is a u16. I looked at the context and it turns out that in vhost_scsi_set_endpoint(), "tpg->tport_tpgt" is used as an offset into the vs_tpg[] array which has VHOST_SCSI_MAX_TARGET (256) elements so anything higher than 255 then it is invalid. I have made that the limit now. In vhost_scsi_send_evt() we mask away values higher than 255, but now that the limit has changed, we don't need the mask. Signed-off-by: Dan Carpenter Signed-off-by: Nicholas Bellinger [ luis: backported to 3.16: functions rename: - tcm_vhost_send_evt -> vhost_scsi_send_evt - tcm_vhost_make_tpg -> vhost_scsi_make_tpg ] Signed-off-by: Luis Henriques --- drivers/vhost/scsi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index befe07b1e71d..0dfb3fd6e836 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1251,7 +1251,7 @@ tcm_vhost_send_evt(struct vhost_scsi *vs, * lun[4-7] need to be zero according to virtio-scsi spec. */ evt->event.lun[0] = 0x01; - evt->event.lun[1] = tpg->tport_tpgt & 0xFF; + evt->event.lun[1] = tpg->tport_tpgt; if (lun->unpacked_lun >= 256) evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ; evt->event.lun[3] = lun->unpacked_lun & 0xFF; @@ -2122,12 +2122,12 @@ tcm_vhost_make_tpg(struct se_wwn *wwn, struct tcm_vhost_tport, tport_wwn); struct tcm_vhost_tpg *tpg; - unsigned long tpgt; + u16 tpgt; int ret; if (strstr(name, "tpgt_") != name) return ERR_PTR(-EINVAL); - if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX) + if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET) return ERR_PTR(-EINVAL); tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);