iio: Return -ENODEV for file operations if the device has been unregistered
If the IIO device has been unregistered return -ENODEV for any further file
operations like read() and ioctl(). This avoids userspace being able to grab new
references to the device.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 36c39dc..6c7a9c5 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -48,6 +48,9 @@
struct iio_dev *indio_dev = filp->private_data;
struct iio_buffer *rb = indio_dev->buffer;
+ if (!indio_dev->info)
+ return -ENODEV;
+
if (!rb || !rb->access->read_first_n)
return -EINVAL;
return rb->access->read_first_n(rb, n, buf);
@@ -62,6 +65,9 @@
struct iio_dev *indio_dev = filp->private_data;
struct iio_buffer *rb = indio_dev->buffer;
+ if (!indio_dev->info)
+ return -ENODEV;
+
poll_wait(filp, &rb->pollq, wait);
if (rb->stufftoread)
return POLLIN | POLLRDNORM;