scsi: iscsi_tcp: Fix UAF during login when accessing the shost ipaddress

[ Upstream commit f484a794e4 ]

If during iscsi_sw_tcp_session_create() iscsi_tcp_r2tpool_alloc() fails,
userspace could be accessing the host's ipaddress attr. If we then free the
session via iscsi_session_teardown() while userspace is still accessing the
session we will hit a use after free bug.

Set the tcp_sw_host->session after we have completed session creation and
can no longer fail.

Link: https://lore.kernel.org/r/20230117193937.21244-3-michael.christie@oracle.com
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Acked-by: Ding Hui <dinghui@sangfor.com.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Mike Christie 2023-01-17 13:39:37 -06:00 committed by Greg Kroah-Hartman
parent b228bd36ec
commit 6abd4698f4

View file

@ -775,7 +775,7 @@ static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf)
{
struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost);
struct iscsi_session *session = tcp_sw_host->session;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
@ -784,6 +784,7 @@ static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
switch (param) {
case ISCSI_HOST_PARAM_IPADDRESS:
session = tcp_sw_host->session;
if (!session)
return -ENOTCONN;
@ -872,12 +873,14 @@ iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
if (!cls_session)
goto remove_host;
session = cls_session->dd_data;
tcp_sw_host = iscsi_host_priv(shost);
tcp_sw_host->session = session;
shost->can_queue = session->scsi_cmds_max;
if (iscsi_tcp_r2tpool_alloc(session))
goto remove_session;
/* We are now fully setup so expose the session to sysfs. */
tcp_sw_host = iscsi_host_priv(shost);
tcp_sw_host->session = session;
return cls_session;
remove_session: