[PATCH 5.12 580/700] scsi: iscsi: Rel ref after iscsi_lookup_endpoint()

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:05:31 EST

From: Mike Christie <michael.christie@xxxxxxxxxx>

[ Upstream commit 9e5fe1700896c85040943fdc0d3fee0dd3e0d36f ]

Subsequent commits allow the kernel to do ep_disconnect. In that case we
will have to get a proper refcount on the ep so one thread does not delete
it from under another.

Link: https://lore.kernel.org/r/20210525181821.7617-7-michael.christie@xxxxxxxxxx
Reviewed-by: Lee Duncan <lduncan@xxxxxxxx>
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/ulp/iser/iscsi_iser.c | 1 +
drivers/scsi/be2iscsi/be_iscsi.c | 19 ++++++++++++------
drivers/scsi/bnx2i/bnx2i_iscsi.c | 23 +++++++++++++++-------
drivers/scsi/cxgbi/libcxgbi.c | 12 ++++++++----
drivers/scsi/qedi/qedi_iscsi.c | 25 +++++++++++++++++-------
drivers/scsi/qla4xxx/ql4_os.c | 1 +
drivers/scsi/scsi_transport_iscsi.c | 25 ++++++++++++++++--------
include/scsi/scsi_transport_iscsi.h | 1 +
8 files changed, 75 insertions(+), 32 deletions(-)

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 6baebcb6d14d..776e46ee95da 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -506,6 +506,7 @@ iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
iser_conn->iscsi_conn = conn;

out:
+ iscsi_put_endpoint(ep);
mutex_unlock(&iser_conn->state_mutex);
return error;
}
diff --git a/drivers/scsi/be2iscsi/be_iscsi.c b/drivers/scsi/be2iscsi/be_iscsi.c
index a13c203ef7a9..c4881657a807 100644
--- a/drivers/scsi/be2iscsi/be_iscsi.c
+++ b/drivers/scsi/be2iscsi/be_iscsi.c
@@ -182,6 +182,7 @@ int beiscsi_conn_bind(struct iscsi_cls_session *cls_session,
struct beiscsi_endpoint *beiscsi_ep;
struct iscsi_endpoint *ep;
uint16_t cri_index;
+ int rc = 0;

ep = iscsi_lookup_endpoint(transport_fd);
if (!ep)
@@ -189,15 +190,17 @@ int beiscsi_conn_bind(struct iscsi_cls_session *cls_session,

beiscsi_ep = ep->dd_data;

- if (iscsi_conn_bind(cls_session, cls_conn, is_leading))
- return -EINVAL;
+ if (iscsi_conn_bind(cls_session, cls_conn, is_leading)) {
+ rc = -EINVAL;
+ goto put_ep;
+ }

if (beiscsi_ep->phba != phba) {
beiscsi_log(phba, KERN_ERR, BEISCSI_LOG_CONFIG,
"BS_%d : beiscsi_ep->hba=%p not equal to phba=%p\n",
beiscsi_ep->phba, phba);
-
- return -EEXIST;
+ rc = -EEXIST;
+ goto put_ep;
}
cri_index = BE_GET_CRI_FROM_CID(beiscsi_ep->ep_cid);
if (phba->conn_table[cri_index]) {
@@ -209,7 +212,8 @@ int beiscsi_conn_bind(struct iscsi_cls_session *cls_session,
beiscsi_ep->ep_cid,
beiscsi_conn,
phba->conn_table[cri_index]);
- return -EINVAL;
+ rc = -EINVAL;
+ goto put_ep;
}
}

@@ -226,7 +230,10 @@ int beiscsi_conn_bind(struct iscsi_cls_session *cls_session,
"BS_%d : cid %d phba->conn_table[%u]=%p\n",
beiscsi_ep->ep_cid, cri_index, beiscsi_conn);
phba->conn_table[cri_index] = beiscsi_conn;
- return 0;
+
+put_ep:
+ iscsi_put_endpoint(ep);
+ return rc;
}

static int beiscsi_iface_create_ipv4(struct beiscsi_hba *phba)
diff --git a/drivers/scsi/bnx2i/bnx2i_iscsi.c b/drivers/scsi/bnx2i/bnx2i_iscsi.c
index b6c1da46d582..2ad85c6b99fd 100644
--- a/drivers/scsi/bnx2i/bnx2i_iscsi.c
+++ b/drivers/scsi/bnx2i/bnx2i_iscsi.c
@@ -1420,17 +1420,23 @@ static int bnx2i_conn_bind(struct iscsi_cls_session *cls_session,
* Forcefully terminate all in progress connection recovery at the
* earliest, either in bind(), send_pdu(LOGIN), or conn_start()
*/
- if (bnx2i_adapter_ready(hba))
- return -EIO;
+ if (bnx2i_adapter_ready(hba)) {
+ ret_code = -EIO;
+ goto put_ep;
+ }

bnx2i_ep = ep->dd_data;
if ((bnx2i_ep->state == EP_STATE_TCP_FIN_RCVD) ||
- (bnx2i_ep->state == EP_STATE_TCP_RST_RCVD))
+ (bnx2i_ep->state == EP_STATE_TCP_RST_RCVD)) {
/* Peer disconnect via' FIN or RST */
- return -EINVAL;
+ ret_code = -EINVAL;
+ goto put_ep;
+ }

- if (iscsi_conn_bind(cls_session, cls_conn, is_leading))
- return -EINVAL;
+ if (iscsi_conn_bind(cls_session, cls_conn, is_leading)) {
+ ret_code = -EINVAL;
+ goto put_ep;
+ }

if (bnx2i_ep->hba != hba) {
/* Error - TCP connection does not belong to this device
@@ -1441,7 +1447,8 @@ static int bnx2i_conn_bind(struct iscsi_cls_session *cls_session,
iscsi_conn_printk(KERN_ALERT, cls_conn->dd_data,
"belong to hba (%s)\n",
hba->netdev->name);
- return -EEXIST;
+ ret_code = -EEXIST;
+ goto put_ep;
}
bnx2i_ep->conn = bnx2i_conn;
bnx2i_conn->ep = bnx2i_ep;
@@ -1458,6 +1465,8 @@ static int bnx2i_conn_bind(struct iscsi_cls_session *cls_session,
bnx2i_put_rq_buf(bnx2i_conn, 0);

bnx2i_arm_cq_event_coalescing(bnx2i_conn->ep, CNIC_ARM_CQE);
+put_ep:
+ iscsi_put_endpoint(ep);
return ret_code;
}

diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
index f078b3c4e083..f6bcae829c29 100644
--- a/drivers/scsi/cxgbi/libcxgbi.c
+++ b/drivers/scsi/cxgbi/libcxgbi.c
@@ -2690,11 +2690,13 @@ int cxgbi_bind_conn(struct iscsi_cls_session *cls_session,
err = csk->cdev->csk_ddp_setup_pgidx(csk, csk->tid,
ppm->tformat.pgsz_idx_dflt);
if (err < 0)
- return err;
+ goto put_ep;

err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
- if (err)
- return -EINVAL;
+ if (err) {
+ err = -EINVAL;
+ goto put_ep;
+ }

/* calculate the tag idx bits needed for this conn based on cmds_max */
cconn->task_idx_bits = (__ilog2_u32(conn->session->cmds_max - 1)) + 1;
@@ -2715,7 +2717,9 @@ int cxgbi_bind_conn(struct iscsi_cls_session *cls_session,
/* init recv engine */
iscsi_tcp_hdr_recv_prep(tcp_conn);

- return 0;
+put_ep:
+ iscsi_put_endpoint(ep);
+ return err;
}
EXPORT_SYMBOL_GPL(cxgbi_bind_conn);

diff --git a/drivers/scsi/qedi/qedi_iscsi.c b/drivers/scsi/qedi/qedi_iscsi.c
index ef16537c523c..087c7ff28cd5 100644
--- a/drivers/scsi/qedi/qedi_iscsi.c
+++ b/drivers/scsi/qedi/qedi_iscsi.c
@@ -377,6 +377,7 @@ static int qedi_conn_bind(struct iscsi_cls_session *cls_session,
struct qedi_ctx *qedi = iscsi_host_priv(shost);
struct qedi_endpoint *qedi_ep;
struct iscsi_endpoint *ep;
+ int rc = 0;

ep = iscsi_lookup_endpoint(transport_fd);
if (!ep)
@@ -384,11 +385,16 @@ static int qedi_conn_bind(struct iscsi_cls_session *cls_session,

qedi_ep = ep->dd_data;
if ((qedi_ep->state == EP_STATE_TCP_FIN_RCVD) ||
- (qedi_ep->state == EP_STATE_TCP_RST_RCVD))
- return -EINVAL;
+ (qedi_ep->state == EP_STATE_TCP_RST_RCVD)) {
+ rc = -EINVAL;
+ goto put_ep;
+ }
+
+ if (iscsi_conn_bind(cls_session, cls_conn, is_leading)) {
+ rc = -EINVAL;
+ goto put_ep;
+ }

- if (iscsi_conn_bind(cls_session, cls_conn, is_leading))
- return -EINVAL;

qedi_ep->conn = qedi_conn;
qedi_conn->ep = qedi_ep;
@@ -398,13 +404,18 @@ static int qedi_conn_bind(struct iscsi_cls_session *cls_session,
qedi_conn->cmd_cleanup_req = 0;
qedi_conn->cmd_cleanup_cmpl = 0;

- if (qedi_bind_conn_to_iscsi_cid(qedi, qedi_conn))
- return -EINVAL;
+ if (qedi_bind_conn_to_iscsi_cid(qedi, qedi_conn)) {
+ rc = -EINVAL;
+ goto put_ep;
+ }
+

spin_lock_init(&qedi_conn->tmf_work_lock);
INIT_LIST_HEAD(&qedi_conn->tmf_work_list);
init_waitqueue_head(&qedi_conn->wait_queue);
- return 0;
+put_ep:
+ iscsi_put_endpoint(ep);
+ return rc;
}

static int qedi_iscsi_update_conn(struct qedi_ctx *qedi,
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index ff663cb330c2..ea128da08537 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -3235,6 +3235,7 @@ static int qla4xxx_conn_bind(struct iscsi_cls_session *cls_session,
conn = cls_conn->dd_data;
qla_conn = conn->dd_data;
qla_conn->qla_ep = ep->dd_data;
+ iscsi_put_endpoint(ep);
return 0;
}

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 2eb77f69fe0c..bab6654d8ee9 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -266,9 +266,20 @@ void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
}
EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);

+void iscsi_put_endpoint(struct iscsi_endpoint *ep)
+{
+ put_device(&ep->dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_put_endpoint);
+
+/**
+ * iscsi_lookup_endpoint - get ep from handle
+ * @handle: endpoint handle
+ *
+ * Caller must do a iscsi_put_endpoint.
+ */
struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
{
- struct iscsi_endpoint *ep;
struct device *dev;

dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
@@ -276,13 +287,7 @@ struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
if (!dev)
return NULL;

- ep = iscsi_dev_to_endpoint(dev);
- /*
- * we can drop this now because the interface will prevent
- * removals and lookups from racing.
- */
- put_device(dev);
- return ep;
+ return iscsi_dev_to_endpoint(dev);
}
EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);

@@ -2990,6 +2995,7 @@ static int iscsi_if_ep_disconnect(struct iscsi_transport *transport,
}

transport->ep_disconnect(ep);
+ iscsi_put_endpoint(ep);
return 0;
}

@@ -3015,6 +3021,7 @@ iscsi_if_transport_ep(struct iscsi_transport *transport,

ev->r.retcode = transport->ep_poll(ep,
ev->u.ep_poll.timeout_ms);
+ iscsi_put_endpoint(ep);
break;
case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
rc = iscsi_if_ep_disconnect(transport,
@@ -3698,6 +3705,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
ev->u.c_bound_session.initial_cmdsn,
ev->u.c_bound_session.cmds_max,
ev->u.c_bound_session.queue_depth);
+ iscsi_put_endpoint(ep);
break;
case ISCSI_UEVENT_DESTROY_SESSION:
session = iscsi_session_lookup(ev->u.d_session.sid);
@@ -3769,6 +3777,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
mutex_lock(&conn->ep_mutex);
conn->ep = ep;
mutex_unlock(&conn->ep_mutex);
+ iscsi_put_endpoint(ep);
} else
iscsi_cls_conn_printk(KERN_ERR, conn,
"Could not set ep conn "
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 8874016b3c9a..d36a72cf049f 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -442,6 +442,7 @@ extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);
+extern void iscsi_put_endpoint(struct iscsi_endpoint *ep);
extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd);
extern struct iscsi_iface *iscsi_create_iface(struct Scsi_Host *shost,
struct iscsi_transport *t,
--
2.30.2