From c0a2e4d10d9366ada133a8ae4ff2f32397f8b15b Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 4 Feb 2019 17:40:09 +0100 Subject: [PATCH] s390/qeth: conclude all event processing before offlining a card 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 Signed-off-by: David S. Miller --- 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 1cf45ace0dd0..122059ecad84 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -790,6 +790,7 @@ 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)]; @@ -963,7 +964,6 @@ 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 30679bfc8a1b..89f912213e62 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -74,8 +74,7 @@ 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) { @@ -1469,6 +1468,10 @@ 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)) @@ -1484,6 +1487,8 @@ out_data: 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: @@ -5031,6 +5036,7 @@ 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 9fec0117fc00..a43de2f9bcac 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -369,6 +369,8 @@ 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, @@ -1436,7 +1438,7 @@ 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 { @@ -1508,7 +1510,7 @@ 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 5e810561cb12..df34bff4ac31 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -1433,6 +1433,8 @@ 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); } /* -- 2.20.1