[PATCH 1/2] [media] tlg2300: implement error handling in poseidon_probe()

[PATCH 1/2] [media] tlg2300: implement error handling in poseidon_probe()

[Alexey Khoroshilov]

All poseidon init functions properly return error codes,
but they are ignored by poseidon_probe(). The patch implements
handling of error cases.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
---
 drivers/media/usb/tlg2300/pd-main.c | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/media/usb/tlg2300/pd-main.c b/drivers/media/usb/tlg2300/pd-main.c
index e07e4c6..ca5e1bc 100644
--- a/drivers/media/usb/tlg2300/pd-main.c
+++ b/drivers/media/usb/tlg2300/pd-main.c
@@ -436,12 +436,22 @@ static int poseidon_probe(struct usb_interface *interface,
 
 		/* register v4l2 device */
 		ret = v4l2_device_register(&interface->dev, &pd->v4l2_dev);
+		if (ret)
+			goto err_v4l2;
 
 		/* register devices in directory /dev */
 		ret = pd_video_init(pd);
-		poseidon_audio_init(pd);
-		poseidon_fm_init(pd);
-		pd_dvb_usb_device_init(pd);
+		if (ret)
+			goto err_video;
+		ret = poseidon_audio_init(pd);
+		if (ret)
+			goto err_audio;
+		ret = poseidon_fm_init(pd);
+		if (ret)
+			goto err_fm;
+		ret = pd_dvb_usb_device_init(pd);
+		if (ret)
+			goto err_dvb;
 
 		INIT_LIST_HEAD(&pd->device_list);
 		list_add_tail(&pd->device_list, &pd_device_list);
@@ -459,6 +469,17 @@ static int poseidon_probe(struct usb_interface *interface,
 	}
 #endif
 	return 0;
+err_dvb:
+	poseidon_fm_exit(pd);
+err_fm:
+	poseidon_audio_free(pd);
+err_audio:
+	pd_video_exit(pd);
+err_video:
+	v4l2_device_unregister(&pd->v4l2_dev);
+err_v4l2:
+	kfree(pd);
+	return ret;
 }
 
 static void poseidon_disconnect(struct usb_interface *interface)
-- 
1.8.1.2

[PATCH 2/2] [media] tlg2300: fix checking firmware in poseidon_probe()

[Alexey Khoroshilov]

check_firmware() makes sure firmware is in a device.
It returns zero on success and error code otherwise.
Also it sets down_firmware flag to 1 if downloading occurs.

The only caller poseidon_probe() checks down_firmware flag and
returns 0 without any initialization if it is set.

That looks very strange, so the patch removes down_firmware argument
of check_firmware() and returns error code if check_firmware() fails
in poseidon_probe().

Not tested on real hardware.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
---
 drivers/media/usb/tlg2300/pd-main.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/media/usb/tlg2300/pd-main.c b/drivers/media/usb/tlg2300/pd-main.c
index ca5e1bc..95f94e5 100644
--- a/drivers/media/usb/tlg2300/pd-main.c
+++ b/drivers/media/usb/tlg2300/pd-main.c
@@ -375,7 +375,7 @@ static inline void set_map_flags(struct poseidon *pd, struct usb_device *udev)
 }
 #endif
 
-static int check_firmware(struct usb_device *udev, int *down_firmware)
+static int check_firmware(struct usb_device *udev)
 {
 	void *buf;
 	int ret;
@@ -395,10 +395,8 @@ static int check_firmware(struct usb_device *udev, int *down_firmware)
 			 USB_CTRL_GET_TIMEOUT);
 	kfree(buf);
 
-	if (ret < 0) {
-		*down_firmware = 1;
+	if (ret < 0)
 		return firmware_download(udev);
-	}
 	return 0;
 }
 
@@ -411,9 +409,9 @@ static int poseidon_probe(struct usb_interface *interface,
 	int new_one = 0;
 
 	/* download firmware */
-	check_firmware(udev, &ret);
+	ret = check_firmware(udev);
 	if (ret)
-		return 0;
+		return ret;
 
 	/* Do I recovery from the hibernate ? */
 	pd = find_old_poseidon(udev);
-- 
1.8.1.2