Messages in this thread Patch in this message | | | From | Pavel Skripkin <> | Subject | [PATCH v2] media: mxl111sf: change mutex_init() location | Date | Thu, 19 Aug 2021 13:38:59 +0300 |
| |
Syzbot reported, that mxl111sf_ctrl_msg() uses uninitialized mutex. The problem was in wrong mutex_init() location.
Previous mutex_init(&state->msg_lock) call was in ->init() function, but dvb_usbv2_init() has this order of calls:
dvb_usbv2_init() dvb_usbv2_adapter_init() dvb_usbv2_adapter_frontend_init() props->frontend_attach()
props->init()
Since mxl111sf_* devices call mxl111sf_ctrl_msg() in ->frontend_attach() internally we need to initialize state->msg_lock before frontend_attach(). To achieve it, ->probe() call added to all mxl111sf_* devices, which will simply initiaize mutex.
Reported-and-tested-by: syzbot+5ca0bf339f13c4243001@syzkaller.appspotmail.com Fixes: 8572211842af ("[media] mxl111sf: convert to new DVB USB") Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> ---
Changes in v2: Addressed same bug in all mxl111sf_* devices by adding ->probe call
--- drivers/media/usb/dvb-usb-v2/mxl111sf.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/media/usb/dvb-usb-v2/mxl111sf.c b/drivers/media/usb/dvb-usb-v2/mxl111sf.c index 7865fa0a8295..b9714ce994d1 100644 --- a/drivers/media/usb/dvb-usb-v2/mxl111sf.c +++ b/drivers/media/usb/dvb-usb-v2/mxl111sf.c @@ -1074,6 +1074,14 @@ static int mxl111sf_get_stream_config_dvbt(struct dvb_frontend *fe, return 0; } +static int mxl111sf_probe(struct dvb_usb_device *dev) +{ + struct mxl111sf_state *state = d_to_priv(dev); + + mutex_init(&state->msg_lock); + return 0; +} + static struct dvb_usb_device_properties mxl111sf_props_dvbt = { .driver_name = KBUILD_MODNAME, .owner = THIS_MODULE, @@ -1083,6 +1091,7 @@ static struct dvb_usb_device_properties mxl111sf_props_dvbt = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_dvbt, .tuner_attach = mxl111sf_attach_tuner, @@ -1124,6 +1133,7 @@ static struct dvb_usb_device_properties mxl111sf_props_atsc = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_atsc, .tuner_attach = mxl111sf_attach_tuner, @@ -1165,6 +1175,7 @@ static struct dvb_usb_device_properties mxl111sf_props_mh = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_mh, .tuner_attach = mxl111sf_attach_tuner, @@ -1233,6 +1244,7 @@ static struct dvb_usb_device_properties mxl111sf_props_atsc_mh = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_atsc_mh, .tuner_attach = mxl111sf_attach_tuner, @@ -1311,6 +1323,7 @@ static struct dvb_usb_device_properties mxl111sf_props_mercury = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_mercury, .tuner_attach = mxl111sf_attach_tuner, @@ -1381,6 +1394,7 @@ static struct dvb_usb_device_properties mxl111sf_props_mercury_mh = { .generic_bulk_ctrl_endpoint = 0x02, .generic_bulk_ctrl_endpoint_response = 0x81, + .probe = mxl111sf_probe, .i2c_algo = &mxl111sf_i2c_algo, .frontend_attach = mxl111sf_frontend_attach_mercury_mh, .tuner_attach = mxl111sf_attach_tuner, -- 2.32.0
| |