[PATCH v1 59/63] Input: atmel_mxt_ts: Prevent crash due to freeing of input device

From: Jiada Wang
Date: Fri Aug 16 2019 - 04:38:39 EST


From: Bhuvanesh Surachari <Bhuvanesh_Surachari@xxxxxxxxxx>

Move sysfs creation after intializing the input device to
prevent crash due to freeing of input device by function via sysfs.

Signed-off-by: Bhuvanesh Surachari <bhuvanesh_surachari@xxxxxxxxxx>
Signed-off-by: Sanjeev Chugh <sanjeev_chugh@xxxxxxxxxx>
Signed-off-by: George G. Davis <george_davis@xxxxxxxxxx>
Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 431c2c54eab0..8e95f46a30d7 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -2962,6 +2962,8 @@ static int mxt_initialize_input_device(struct mxt_data *data)
goto err_free_mem;
}

+ data->input_dev = input_dev;
+
if (data->gpio_attrs.attrs) {
error = sysfs_create_group(&input_dev->dev.kobj,
&data->gpio_attrs);
@@ -2972,11 +2974,10 @@ static int mxt_initialize_input_device(struct mxt_data *data)
}
}

- data->input_dev = input_dev;
-
return 0;

err_free_mem:
+ data->input_dev = NULL;
input_free_device(input_dev);
return error;
}
@@ -4597,13 +4598,6 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
msleep(MXT_RESET_TIME);
}

- error = sysfs_create_group(&client->dev.kobj, &mxt_fw_attr_group);
- if (error) {
- dev_err(&client->dev, "Failure %d creating fw sysfs group\n",
- error);
- return error;
- }
-
INIT_WORK(&data->watchdog_work, mxt_watchdog_work);

/* setup watchdog timer */
@@ -4613,11 +4607,18 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)

error = mxt_initialize(data);
if (error)
- goto err_free_object;
+ goto err_del_wd_timer;
+
+ error = sysfs_create_group(&client->dev.kobj, &mxt_fw_attr_group);
+ if (error) {
+ dev_err(&client->dev, "Failure %d creating fw sysfs group\n",
+ error);
+ goto err_del_wd_timer;
+ }

return 0;

-err_free_object:
+err_del_wd_timer:
cancel_work_sync(&data->watchdog_work);
mxt_stop_wd_timer(data);
mxt_free_input_device(data);
--
2.19.2