From: Johan Hovold johan@kernel.org
commit 25d5ce3a606a1eb23a9265d615a92a876ff9cb5f upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c +++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c @@ -609,8 +609,9 @@ static int rtl28xxu_read_config(struct 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");