From def70c33c478259057486c3c7798737b34797b0d Mon Sep 17 00:00:00 2001
From: Chris Leech <cleech@redhat.com>
Date: Tue, 23 Feb 2021 21:39:01 -0800
Subject: [PATCH] scsi: iscsi: Verify lengths on passthrough PDUs
commit f9dbdf97a5bd92b1a49cee3d591b55b11fd7a6d5 upstream.
Open-iSCSI sends passthrough PDUs over netlink, but the kernel should be
verifying that the provided PDU header and data lengths fall within the
netlink message to prevent accessing beyond that in memory.
Cc: stable@vger.kernel.org
Reported-by: Adam Nichols <adam@grimm-co.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/scsi/scsi_transport_iscsi.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 0db7fc78cc7d..a26df7d6d5d1 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -3509,6 +3509,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
{
int err = 0;
u32 portid;
+ u32 pdu_len;
struct iscsi_uevent *ev = nlmsg_data(nlh);
struct iscsi_transport *transport = NULL;
struct iscsi_internal *priv;
@@ -3626,6 +3627,14 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
err = -EINVAL;
break;
case ISCSI_UEVENT_SEND_PDU:
+ pdu_len = nlh->nlmsg_len - sizeof(*nlh) - sizeof(*ev);
+
+ if ((ev->u.send_pdu.hdr_size > pdu_len) ||
+ (ev->u.send_pdu.data_size > (pdu_len - ev->u.send_pdu.hdr_size))) {
+ err = -EINVAL;
+ break;
+ }
+
conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
if (conn)
ev->r.retcode = transport->send_pdu(conn,