Merge tag 'media/v6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

Pull media fixes from Mauro Carvalho Chehab:
 "Several fixes for the dvb core and drivers:

   - fix UAF and null pointer de-reference in DVB core

   - fix kernel runtime warning for blocking operation in wait_event*()
     in dvb core

   - fix write size bug in DVB conditional access core

   - fix dvb demux continuity counter debug check logic

   - randconfig build fixes in pvrusb2 and mn88443x

   - fix memory leak in ttusb-dec

   - fix netup_unidvb probe-time error check logic

   - improve error handling in dw2102 if it can't retrieve DVB MAC
     address"

* tag 'media/v6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: dvb-core: Fix use-after-free due to race condition at dvb_ca_en50221
  media: dvb-core: Fix kernel WARNING for blocking operation in wait_event*()
  media: dvb-core: Fix use-after-free due to race at dvb_register_device()
  media: dvb-core: Fix use-after-free due on race condition at dvb_net
  media: dvb-core: Fix use-after-free on race condition at dvb_frontend
  media: mn88443x: fix !CONFIG_OF error by drop of_match_ptr from ID table
  media: ttusb-dec: fix memory leak in ttusb_dec_exit_dvb()
  media: dvb_ca_en50221: fix a size write bug
  media: netup_unidvb: fix irq init by register it at the end of probe
  media: dvb-usb: dw2102: fix uninit-value in su3000_read_mac_address
  media: dvb-usb: digitv: fix null-ptr-deref in digitv_i2c_xfer()
  media: dvb-usb-v2: rtl28xxu: fix null-ptr-deref in rtl28xxu_i2c_xfer
  media: dvb-usb-v2: ce6230: fix null-ptr-deref in ce6230_i2c_master_xfer()
  media: dvb-usb-v2: ec168: fix null-ptr-deref in ec168_i2c_xfer()
  media: dvb-usb: az6027: fix three null-ptr-deref in az6027_i2c_xfer()
  media: netup_unidvb: fix use-after-free at del_timer()
  media: dvb_demux: fix a bug for the continuity counter
  media: pvrusb2: fix DVB_CORE dependency

1 files changed, 63 insertions, 21 deletions

diff --git a/drivers/media/dvb-core/dvbdev.c b/drivers/media/dvb-core/dvbdev.c
index e9b3ce09e534..a4b05e366ccc 100644
--- a/drivers/media/dvb-core/dvbdev.c
+++ b/drivers/media/dvb-core/dvbdev.c
@@ -27,6 +27,7 @@
 #include <media/tuner.h>
 
 static DEFINE_MUTEX(dvbdev_mutex);
+static LIST_HEAD(dvbdevfops_list);
 static int dvbdev_debug;
 
 module_param(dvbdev_debug, int, 0644);
@@ -453,14 +454,15 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 			enum dvb_device_type type, int demux_sink_pads)
 {
 	struct dvb_device *dvbdev;
-	struct file_operations *dvbdevfops;
+	struct file_operations *dvbdevfops = NULL;
+	struct dvbdevfops_node *node = NULL, *new_node = NULL;
 	struct device *clsdev;
 	int minor;
 	int id, ret;
 
 	mutex_lock(&dvbdev_register_lock);
 
-	if ((id = dvbdev_get_free_id (adap, type)) < 0){
+	if ((id = dvbdev_get_free_id (adap, type)) < 0) {
 		mutex_unlock(&dvbdev_register_lock);
 		*pdvbdev = NULL;
 		pr_err("%s: couldn't find free device id\n", __func__);
@@ -468,18 +470,45 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 	}
 
 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
-
 	if (!dvbdev){
 		mutex_unlock(&dvbdev_register_lock);
 		return -ENOMEM;
 	}
 
-	dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL);
+	/*
+	 * When a device of the same type is probe()d more than once,
+	 * the first allocated fops are used. This prevents memory leaks
+	 * that can occur when the same device is probe()d repeatedly.
+	 */
+	list_for_each_entry(node, &dvbdevfops_list, list_head) {
+		if (node->fops->owner == adap->module &&
+				node->type == type &&
+				node->template == template) {
+			dvbdevfops = node->fops;
+			break;
+		}
+	}
 
-	if (!dvbdevfops){
-		kfree (dvbdev);
-		mutex_unlock(&dvbdev_register_lock);
-		return -ENOMEM;
+	if (dvbdevfops == NULL) {
+		dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL);
+		if (!dvbdevfops) {
+			kfree(dvbdev);
+			mutex_unlock(&dvbdev_register_lock);
+			return -ENOMEM;
+		}
+
+		new_node = kzalloc(sizeof(struct dvbdevfops_node), GFP_KERNEL);
+		if (!new_node) {
+			kfree(dvbdevfops);
+			kfree(dvbdev);
+			mutex_unlock(&dvbdev_register_lock);
+			return -ENOMEM;
+		}
+
+		new_node->fops = dvbdevfops;
+		new_node->type = type;
+		new_node->template = template;
+		list_add_tail (&new_node->list_head, &dvbdevfops_list);
 	}
 
 	memcpy(dvbdev, template, sizeof(struct dvb_device));
@@ -490,20 +519,20 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 	dvbdev->priv = priv;
 	dvbdev->fops = dvbdevfops;
 	init_waitqueue_head (&dvbdev->wait_queue);
-
 	dvbdevfops->owner = adap->module;
-
 	list_add_tail (&dvbdev->list_head, &adap->device_list);
-
 	down_write(&minor_rwsem);
 #ifdef CONFIG_DVB_DYNAMIC_MINORS
 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
 		if (dvb_minors[minor] == NULL)
 			break;
-
 	if (minor == MAX_DVB_MINORS) {
+		if (new_node) {
+			list_del (&new_node->list_head);
+			kfree(dvbdevfops);
+			kfree(new_node);
+		}
 		list_del (&dvbdev->list_head);
-		kfree(dvbdevfops);
 		kfree(dvbdev);
 		up_write(&minor_rwsem);
 		mutex_unlock(&dvbdev_register_lock);
@@ -512,41 +541,47 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 #else
 	minor = nums2minor(adap->num, type, id);
 #endif
-
 	dvbdev->minor = minor;
 	dvb_minors[minor] = dvb_device_get(dvbdev);
 	up_write(&minor_rwsem);
-
 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
 	if (ret) {
 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
 		      __func__);
-
+		if (new_node) {
+			list_del (&new_node->list_head);
+			kfree(dvbdevfops);
+			kfree(new_node);
+		}
 		dvb_media_device_free(dvbdev);
 		list_del (&dvbdev->list_head);
-		kfree(dvbdevfops);
 		kfree(dvbdev);
 		mutex_unlock(&dvbdev_register_lock);
 		return ret;
 	}
 
-	mutex_unlock(&dvbdev_register_lock);
-
 	clsdev = device_create(dvb_class, adap->device,
 			       MKDEV(DVB_MAJOR, minor),
 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
 	if (IS_ERR(clsdev)) {
 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
+		if (new_node) {
+			list_del (&new_node->list_head);
+			kfree(dvbdevfops);
+			kfree(new_node);
+		}
 		dvb_media_device_free(dvbdev);
 		list_del (&dvbdev->list_head);
-		kfree(dvbdevfops);
 		kfree(dvbdev);
+		mutex_unlock(&dvbdev_register_lock);
 		return PTR_ERR(clsdev);
 	}
+
 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
 		adap->num, dnames[type], id, minor, minor);
 
+	mutex_unlock(&dvbdev_register_lock);
 	return 0;
 }
 EXPORT_SYMBOL(dvb_register_device);
@@ -575,7 +610,6 @@ static void dvb_free_device(struct kref *ref)
 {
 	struct dvb_device *dvbdev = container_of(ref, struct dvb_device, ref);
 
-	kfree (dvbdev->fops);
 	kfree (dvbdev);
 }
 
@@ -1081,9 +1115,17 @@ error:
 
 static void __exit exit_dvbdev(void)
 {
+	struct dvbdevfops_node *node, *next;
+
 	class_destroy(dvb_class);
 	cdev_del(&dvb_device_cdev);
 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
+
+	list_for_each_entry_safe(node, next, &dvbdevfops_list, list_head) {
+		list_del (&node->list_head);
+		kfree(node->fops);
+		kfree(node);
+	}
 }
 
 subsys_initcall(init_dvbdev);