From 733d7ab6c5bccef9a644afdcffc1e2369f0d5b6e Mon Sep 17 00:00:00 2001 From: Prabhakar Lad Date: Thu, 20 Jul 2017 08:02:09 -0400 Subject: [PATCH] media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl 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. Fixes: 5f15fbb68fd7 ("V4L/DVB (12251): v4l: dm644x ccdc module for vpfe capture driver") Signed-off-by: Lad, Prabhakar Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/platform/davinci/vpfe_capture.c | 22 ++-------------------- 1 file changed, 2 insertions(+), 20 deletions(-) diff --git a/drivers/media/platform/davinci/vpfe_capture.c b/drivers/media/platform/davinci/vpfe_capture.c index 6efb2f1..bdb7a0a 100644 --- a/drivers/media/platform/davinci/vpfe_capture.c +++ b/drivers/media/platform/davinci/vpfe_capture.c @@ -1725,27 +1725,9 @@ static long vpfe_param_handler(struct file *file, void *priv, 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; -- 2.7.4