diff options
authorDan Carpenter <dan.carpenter@oracle.com>2015-02-05 10:37:33 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-10-01 12:07:34 +0200
commitfa83234f6a4e7b378f0da63938a09b9e8d535c4d (patch)
parent7bf24986e3c2e4b818be4a6172aebb3784c6bcda (diff)
vhost/scsi: potential memory corruption
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 <dan.carpenter@oracle.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> [ The affected function was renamed to vhost_scsi_make_tpg before the vulnerability was announced, I ported it to 3.10 stable and changed the code in function tcm_vhost_make_tpg] Signed-off-by: Wang Long <long.wanglong@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index fb97bc0b80e7..2947eda522b2 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1088,7 +1088,7 @@ static void tcm_vhost_send_evt(struct vhost_scsi *vs, struct tcm_vhost_tpg *tpg,
* 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;
@@ -1894,12 +1894,12 @@ static struct se_portal_group *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);