[git:media_stage/master] media: rtl28xxu: fix zero-length control request

[git:media_stage/master] media: rtl28xxu: fix zero-length control request

[Mauro Carvalho Chehab]

This is an automatic generated email to let you know that the following patch were queued:

Subject: media: rtl28xxu: fix zero-length control request
Author:  Johan Hovold <johan@kernel.org>
Date:    Mon May 24 13:09:20 2021 +0200

The direction of the pipe argument must match the request-type direction
bit or control requests may fail depending on the host-controller-driver
implementation.

Control transfers without a data stage are treated as OUT requests by
the USB stack and should be using usb_sndctrlpipe(). Failing to do so
will now trigger a warning.

Fix the zero-length i2c-read request used for type detection by
attempting to read a single byte instead.

Reported-by: syzbot+faf11bbadc5a372564da@syzkaller.appspotmail.com
Fixes: d0f232e823af ("[media] rtl28xxu: add heuristic to detect chip type")
Cc: stable@vger.kernel.org      # 4.0
Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

 drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

---

diff --git a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
index 97ed17a141bb..2c04ed8af0e4 100644
--- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
+++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
@@ -612,8 +612,9 @@ static int rtl28xxu_read_config(struct dvb_usb_device *d)
 static int rtl28xxu_identify_state(struct dvb_usb_device *d, const char **name)
 {
 	struct rtl28xxu_dev *dev = d_to_priv(d);
+	u8 buf[1];
 	int ret;
-	struct rtl28xxu_req req_demod_i2c = {0x0020, CMD_I2C_DA_RD, 0, NULL};
+	struct rtl28xxu_req req_demod_i2c = {0x0020, CMD_I2C_DA_RD, 1, buf};
 
 	dev_dbg(&d->intf->dev, "\n");
 

Re: [git:media_stage/master] media: rtl28xxu: fix zero-length control request

[Johan Hovold]

On Wed, Jun 02, 2021 at 12:15:42PM +0000, Mauro Carvalho Chehab wrote:
> This is an automatic generated email to let you know that the following patch were queued:
> 
> Subject: media: rtl28xxu: fix zero-length control request
> Author:  Johan Hovold <johan@kernel.org>
> Date:    Mon May 24 13:09:20 2021 +0200
> 
> The direction of the pipe argument must match the request-type direction
> bit or control requests may fail depending on the host-controller-driver
> implementation.
> 
> Control transfers without a data stage are treated as OUT requests by
> the USB stack and should be using usb_sndctrlpipe(). Failing to do so
> will now trigger a warning.
> 
> Fix the zero-length i2c-read request used for type detection by
> attempting to read a single byte instead.
> 
> Reported-by: syzbot+faf11bbadc5a372564da@syzkaller.appspotmail.com
> Fixes: d0f232e823af ("[media] rtl28xxu: add heuristic to detect chip type")
> Cc: stable@vger.kernel.org      # 4.0
> Cc: Antti Palosaari <crope@iki.fi>
> Signed-off-by: Johan Hovold <johan@kernel.org>
> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

This one caused a regression and a v2 was submitted here:

	https://lore.kernel.org/r/20210531094434.12651-4-johan@kernel.org

Can you drop this one in favour of the v2?

>  drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> ---
> 
> diff --git a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
> index 97ed17a141bb..2c04ed8af0e4 100644
> --- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
> +++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
> @@ -612,8 +612,9 @@ static int rtl28xxu_read_config(struct dvb_usb_device *d)
>  static int rtl28xxu_identify_state(struct dvb_usb_device *d, const char **name)
>  {
>  	struct rtl28xxu_dev *dev = d_to_priv(d);
> +	u8 buf[1];
>  	int ret;
> -	struct rtl28xxu_req req_demod_i2c = {0x0020, CMD_I2C_DA_RD, 0, NULL};
> +	struct rtl28xxu_req req_demod_i2c = {0x0020, CMD_I2C_DA_RD, 1, buf};
>  
>  	dev_dbg(&d->intf->dev, "\n");
>  

Johan