From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754574AbbEZPoX (ORCPT ); Tue, 26 May 2015 11:44:23 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:34231 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932219AbbEZPnE (ORCPT ); Tue, 26 May 2015 11:43:04 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Dan Carpenter , Nicholas Bellinger , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 91/92] vhost/scsi: potential memory corruption Date: Tue, 26 May 2015 08:41:35 -0700 Message-Id: <1432654896-28478-92-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1432654896-28478-1-git-send-email-kamal@canonical.com> References: <1432654896-28478-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt1 -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 Reference: CVE-2015-4036 Signed-off-by: Kamal Mostafa --- 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 d695b16..be0517f 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1253,7 +1253,7 @@ 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; @@ -2124,12 +2124,12 @@ 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); -- 1.9.1