Patch "media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
media-platform-davinci-return-einval-for-vpfe_cmd_s_ccdc_raw_params-ioctl.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Prabhakar Lad <[email protected]>
Date: Thu, 20 Jul 2017 08:02:09 -0400
Subject: media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl

From: Prabhakar Lad <[email protected]>

commit da05d52d2f0f6bd61094a0cd045fed94bf7d673a upstream.

this patch makes sure VPFE_CMD_S_CCDC_RAW_PARAMS ioctl no longer works for vpfe_capture driver with a minimal patch suitable for backporting.

- This ioctl was never in public api and was only defined in kernel header.
- The function set_params constantly mixes up pointers and phys_addr_t numbers.
- This is part of a 'VPFE_CMD_S_CCDC_RAW_PARAMS' ioctl command that is described as an 'experimental ioctl that will change in future kernels'.
- The code to allocate the table never gets called after we copy_from_user the user input over the kernel settings, and then compare them for inequality.
- We then go on to use an address provided by user space as both the __user pointer for input and pass it through phys_to_virt to come up with a kernel pointer to copy the data to. This looks like a trivially exploitable root hole.

Due to these reasons we make sure this ioctl now returns -EINVAL and backport this patch as far as possible.

---
 drivers/media/platform/davinci/vpfe_capture.c |   22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

@@ -1709,27 +1709,9 @@ static long vpfe_param_handler(struct fi
 
 	switch (cmd) {
 	case VPFE_CMD_S_CCDC_RAW_PARAMS:
+		ret = -EINVAL;
 		v4l2_warn(&vpfe_dev->v4l2_dev,
-			  "VPFE_CMD_S_CCDC_RAW_PARAMS: experimental ioctl\n");
-		if (ccdc_dev->hw_ops.set_params) {
-			ret = ccdc_dev->hw_ops.set_params(param);
-			if (ret) {
-				v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
-					"Error setting parameters in CCDC\n");
-				goto unlock_out;
-			}
-			ret = vpfe_get_ccdc_image_format(vpfe_dev,
-							 &vpfe_dev->fmt);
-			if (ret < 0) {
-				v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
-					"Invalid image format at CCDC\n");
-				goto unlock_out;
-			}
-		} else {
-			ret = -EINVAL;
-			v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
-				"VPFE_CMD_S_CCDC_RAW_PARAMS not supported\n");
-		}
+			"VPFE_CMD_S_CCDC_RAW_PARAMS not supported\n");
 		break;
 	default:
 		ret = -ENOTTY;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/media-platform-davinci-return-einval-for-vpfe_cmd_s_ccdc_raw_params-ioctl.patch