firewire: Track pending transactions and cancel them on cdev release.

Without this, pending transactions will dereference freed memory
if they complete after the device file has been closed.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Kristian Høgsberg 2007-03-07 12:12:50 -05:00 committed by Stefan Richter
parent f319b6a02f
commit 28cf6a04c8

View file

@ -60,6 +60,7 @@ struct response {
struct event event;
struct fw_transaction transaction;
struct client *client;
struct list_head link;
struct fw_cdev_event_response response;
};
@ -74,6 +75,7 @@ struct client {
spinlock_t lock;
struct list_head handler_list;
struct list_head request_list;
struct list_head transaction_list;
u32 request_serial;
struct list_head event_list;
wait_queue_head_t wait;
@ -115,6 +117,7 @@ static int fw_device_op_open(struct inode *inode, struct file *file)
INIT_LIST_HEAD(&client->event_list);
INIT_LIST_HEAD(&client->handler_list);
INIT_LIST_HEAD(&client->request_list);
INIT_LIST_HEAD(&client->transaction_list);
spin_lock_init(&client->lock);
init_waitqueue_head(&client->wait);
@ -299,6 +302,7 @@ complete_transaction(struct fw_card *card, int rcode,
{
struct response *response = data;
struct client *client = response->client;
unsigned long flags;
if (length < response->response.length)
response->response.length = length;
@ -306,6 +310,10 @@ complete_transaction(struct fw_card *card, int rcode,
memcpy(response->response.data, payload,
response->response.length);
spin_lock_irqsave(&client->lock, flags);
list_del(&response->link);
spin_unlock_irqrestore(&client->lock, flags);
response->response.type = FW_CDEV_EVENT_RESPONSE;
response->response.rcode = rcode;
queue_event(client, &response->event,
@ -318,6 +326,7 @@ static ssize_t ioctl_send_request(struct client *client, void __user *arg)
struct fw_device *device = client->device;
struct fw_cdev_send_request request;
struct response *response;
unsigned long flags;
if (copy_from_user(&request, arg, sizeof request))
return -EFAULT;
@ -341,6 +350,10 @@ static ssize_t ioctl_send_request(struct client *client, void __user *arg)
return -EFAULT;
}
spin_lock_irqsave(&client->lock, flags);
list_add_tail(&response->link, &client->transaction_list);
spin_unlock_irqrestore(&client->lock, flags);
fw_send_request(device->card, &response->transaction,
request.tcode & 0x1f,
device->node->node_id,
@ -752,6 +765,7 @@ static int fw_device_op_release(struct inode *inode, struct file *file)
struct address_handler *h, *next_h;
struct request *r, *next_r;
struct event *e, *next_e;
struct response *t, *next_t;
unsigned long flags;
if (client->buffer.pages)
@ -771,9 +785,12 @@ static int fw_device_op_release(struct inode *inode, struct file *file)
kfree(r);
}
/* TODO: wait for all transactions to finish so
* complete_transaction doesn't try to queue up responses
* after we free client. */
list_for_each_entry_safe(t, next_t, &client->transaction_list, link)
fw_cancel_transaction(client->device->card, &t->transaction);
/* FIXME: We should wait for the async tasklets to stop
* running before freeing the memory. */
list_for_each_entry_safe(e, next_e, &client->event_list, link)
kfree(e);