[PATCH 2/2] HID: sensor: custom: Set the owner of the misc file operations

[Chad Aldreda <ca@modelmiser.com>]

hid_sensor_custom_fops has no .owner, so an open file on the misc node
does not pin the module: with the node open, the module can be
unloaded, and the file's later release() calls into freed module text.

Set .owner to THIS_MODULE so misc_open()'s fops_get() takes a module
reference for each open file.

Found by review of the previous fix. Tested in QEMU with the driver
built as a module and the uhid reproducer holding the node open. Without
this change, rmmod succeeds and the later close() oopses in filp_flush()
on a page fault in the unloaded module. With it, rmmod fails while the
node is open, and succeeds after close() with no oops.

Fixes: 4a7de0519df5 ("HID: sensor: Custom and Generic sensor support")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Chad Aldreda <ca@modelmiser.com>
---
 drivers/hid/hid-sensor-custom.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hid/hid-sensor-custom.c b/drivers/hid/hid-sensor-custom.c
index 47800efdaf..bee612eb1d 100644
--- a/drivers/hid/hid-sensor-custom.c
+++ b/drivers/hid/hid-sensor-custom.c
@@ -745,6 +745,7 @@ static __poll_t hid_sensor_custom_poll(struct file *file,
 }
 
 static const struct file_operations hid_sensor_custom_fops = {
+	.owner = THIS_MODULE,
 	.open =  hid_sensor_custom_open,
 	.read =  hid_sensor_custom_read,
 	.release = hid_sensor_custom_release,
-- 
2.43.0