4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit c0a2e4d10d9366ada133a8ae4ff2f32397f8b15b ]
Work for Bridgeport events is currently placed on a driver-wide workqueue. If the card is removed and freed while any such work is still active, this causes a use-after-free. So put the events on a per-card queue, where we can control their lifetime. As we also don't want stale events to last beyond an offline & online cycle, flush this queue when setting the card offline.
Fixes: b4d72c08b358 ("qeth: bridgeport support - basic control") Signed-off-by: Julian Wiedmann jwi@linux.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/s390/net/qeth_core.h | 2 +- drivers/s390/net/qeth_core_main.c | 10 ++++++++-- drivers/s390/net/qeth_l2_main.c | 6 ++++-- drivers/s390/net/qeth_l3_main.c | 2 ++ 4 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 8999be74c545..8f2af450152f 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -791,6 +791,7 @@ struct qeth_card { struct qeth_seqno seqno; struct qeth_card_options options;
+ struct workqueue_struct *event_wq; wait_queue_head_t wait_q; spinlock_t mclock; unsigned long active_vlans[BITS_TO_LONGS(VLAN_N_VID)]; @@ -969,7 +970,6 @@ extern const struct attribute_group *qeth_osn_attr_groups[]; extern const struct attribute_group qeth_device_attr_group; extern const struct attribute_group qeth_device_blkt_group; extern const struct device_type qeth_generic_devtype; -extern struct workqueue_struct *qeth_wq;
int qeth_card_hw_is_reachable(struct qeth_card *); const char *qeth_get_cardname_short(struct qeth_card *); diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 89cc172820ca..ebbc3ad504f9 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -76,8 +76,7 @@ static void qeth_notify_skbs(struct qeth_qdio_out_q *queue, static void qeth_release_skbs(struct qeth_qdio_out_buffer *buf); static int qeth_init_qdio_out_buf(struct qeth_qdio_out_q *, int);
-struct workqueue_struct *qeth_wq; -EXPORT_SYMBOL_GPL(qeth_wq); +static struct workqueue_struct *qeth_wq;
int qeth_card_hw_is_reachable(struct qeth_card *card) { @@ -1471,6 +1470,10 @@ static struct qeth_card *qeth_alloc_card(struct ccwgroup_device *gdev) CARD_RDEV(card) = gdev->cdev[0]; CARD_WDEV(card) = gdev->cdev[1]; CARD_DDEV(card) = gdev->cdev[2]; + + card->event_wq = alloc_ordered_workqueue("%s", 0, dev_name(&gdev->dev)); + if (!card->event_wq) + goto out_wq; if (qeth_setup_channel(&card->read, true)) goto out_ip; if (qeth_setup_channel(&card->write, true)) @@ -1486,6 +1489,8 @@ static struct qeth_card *qeth_alloc_card(struct ccwgroup_device *gdev) out_channel: qeth_clean_channel(&card->read); out_ip: + destroy_workqueue(card->event_wq); +out_wq: dev_set_drvdata(&gdev->dev, NULL); kfree(card); out: @@ -5038,6 +5043,7 @@ static void qeth_core_free_card(struct qeth_card *card) qeth_clean_channel(&card->read); qeth_clean_channel(&card->write); qeth_clean_channel(&card->data); + destroy_workqueue(card->event_wq); qeth_free_qdio_buffers(card); unregister_service_level(&card->qeth_service_level); dev_set_drvdata(&card->gdev->dev, NULL); diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 49fa09c67d49..a6c55cbf3d69 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -391,6 +391,8 @@ static void qeth_l2_stop_card(struct qeth_card *card, int recovery_mode) qeth_clear_cmd_buffers(&card->read); qeth_clear_cmd_buffers(&card->write); } + + flush_workqueue(card->event_wq); }
static int qeth_l2_process_inbound_buffer(struct qeth_card *card, @@ -1455,7 +1457,7 @@ static void qeth_bridge_state_change(struct qeth_card *card, data->card = card; memcpy(&data->qports, qports, sizeof(struct qeth_sbp_state_change) + extrasize); - queue_work(qeth_wq, &data->worker); + queue_work(card->event_wq, &data->worker); }
struct qeth_bridge_host_data { @@ -1527,7 +1529,7 @@ static void qeth_bridge_host_event(struct qeth_card *card, data->card = card; memcpy(&data->hostevs, hostevs, sizeof(struct qeth_ipacmd_addr_change) + extrasize); - queue_work(qeth_wq, &data->worker); + queue_work(card->event_wq, &data->worker); }
/* SETBRIDGEPORT support; sending commands */ diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index d1bf55b5c8e1..29a2408b9282 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -1436,6 +1436,8 @@ static void qeth_l3_stop_card(struct qeth_card *card, int recovery_mode) qeth_clear_cmd_buffers(&card->read); qeth_clear_cmd_buffers(&card->write); } + + flush_workqueue(card->event_wq); }
/*