staging: media: atomisp: Disallow all private IOCTLs

commit 2b7eb2c upstream.

Disallow all private IOCTLs. These aren't quite as safe as one could
assume of IOCTL handlers; disable them for now. Instead of removing the
code, return in the beginning of the function if cmd is non-zero in order
to keep static checkers happy.

Reported-by: Soufiane Dani <soufianeda@tutanota.com>
Closes: https://lore.kernel.org/linux-staging/20260210-atomisp-fix-v1-1-024429cbff31@tutanota.com/
Cc: stable@vger.kernel.org
Fixes: a49d253 ("staging/atomisp: Add support for the Intel IPU v2")
Fixes: ad85094 ("Revert "media: staging: atomisp: Remove driver"")
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Sakari Ailus

drivers/staging/media/atomisp/pci/atomisp_ioctl.c

@@ -1780,6 +1780,10 @@ static long atomisp_vidioc_default(struct file *file, void *fh,
 	struct atomisp_sub_device *asd = atomisp_to_video_pipe(vdev)->asd;
 	int err;
 
+	/* Disable all private IOCTLs for now! */
+	if (cmd)
+		return -EINVAL;
+
 	switch (cmd) {
 	case ATOMISP_IOC_S_SENSOR_RUNMODE:
 		if (IS_ISP2401)